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RetroArch/deps/stb/stb_vorbis.h
2019-06-22 14:52:29 +02:00

3911 lines
127 KiB
C

#ifndef STB_VORBIS_INCLUDE_STB_VORBIS_H
#define STB_VORBIS_INCLUDE_STB_VORBIS_H
#include <assert.h>
#ifdef __cplusplus
extern "C" {
#endif
typedef struct
{
char *alloc_buffer;
int alloc_buffer_length_in_bytes;
} stb_vorbis_alloc;
/* FUNCTIONS USEABLE WITH ALL INPUT MODES */
typedef struct stb_vorbis stb_vorbis;
typedef struct
{
unsigned int sample_rate;
int channels;
unsigned int setup_memory_required;
unsigned int setup_temp_memory_required;
unsigned int temp_memory_required;
int max_frame_size;
} stb_vorbis_info;
/* get general information about the file */
extern stb_vorbis_info stb_vorbis_get_info(stb_vorbis *f);
/* get the last error detected (clears it, too) */
extern int stb_vorbis_get_error(stb_vorbis *f);
/* close an ogg vorbis file and free all memory in use */
extern void stb_vorbis_close(stb_vorbis *f);
/* this function returns the offset (in samples) from the beginning of the
* file that will be returned by the next decode, if it is known, or -1
* otherwise. after a flush_pushdata() call, this may take a while before
* it becomes valid again.
* NOT WORKING YET after a seek with PULLDATA API */
extern int stb_vorbis_get_sample_offset(stb_vorbis *f);
/* returns the current seek point within the file, or offset from the beginning
* of the memory buffer. In pushdata mode it returns 0. */
extern unsigned int stb_vorbis_get_file_offset(stb_vorbis *f);
/* PULLING INPUT API */
#ifndef STB_VORBIS_NO_PULLDATA_API
/* This API assumes stb_vorbis is allowed to pull data from a source--
* either a block of memory containing the _entire_ vorbis stream, or a
* FILE * that you or it create, or possibly some other reading mechanism
* if you go modify the source to replace the FILE * case with some kind
* of callback to your code. (But if you don't support seeking, you may
* just want to go ahead and use pushdata.) */
extern stb_vorbis * stb_vorbis_open_memory(const unsigned char *data, int len,
int *error, stb_vorbis_alloc *alloc_buffer);
/* create an ogg vorbis decoder from an ogg vorbis stream in memory (note
* this must be the entire stream!). on failure, returns NULL and sets *error */
extern int stb_vorbis_seek_frame(stb_vorbis *f, unsigned int sample_number);
extern int stb_vorbis_seek(stb_vorbis *f, unsigned int sample_number);
/* NOT WORKING YET
* these functions seek in the Vorbis file to (approximately) 'sample_number'.
* after calling seek_frame(), the next call to get_frame_*() will include
* the specified sample. after calling stb_vorbis_seek(), the next call to
* stb_vorbis_get_samples_* will start with the specified sample. If you
* do not need to seek to EXACTLY the target sample when using get_samples_*,
* you can also use seek_frame(). */
extern void stb_vorbis_seek_start(stb_vorbis *f);
/* this function is equivalent to stb_vorbis_seek(f,0), but it
* actually works */
extern unsigned int stb_vorbis_stream_length_in_samples(stb_vorbis *f);
extern float stb_vorbis_stream_length_in_seconds(stb_vorbis *f);
/* these functions return the total length of the vorbis stream */
extern int stb_vorbis_get_frame_float(stb_vorbis *f, int *channels, float ***output);
/* decode the next frame and return the number of samples. the number of
* channels returned are stored in *channels (which can be NULL--it is always
* the same as the number of channels reported by get_info). *output will
* contain an array of float* buffers, one per channel. These outputs will
* be overwritten on the next call to stb_vorbis_get_frame_*.
*
* You generally should not intermix calls to stb_vorbis_get_frame_*()
* and stb_vorbis_get_samples_*(), since the latter calls the former.
*/
extern int stb_vorbis_get_samples_float_interleaved(stb_vorbis *f, int channels, float *buffer, int num_floats);
extern int stb_vorbis_get_samples_float(stb_vorbis *f, int channels, float **buffer, int num_samples);
/* gets num_samples samples, not necessarily on a frame boundary--this requires
* buffering so you have to supply the buffers. DOES NOT APPLY THE COERCION RULES.
* Returns the number of samples stored per channel; it may be less than requested
* at the end of the file. If there are no more samples in the file, returns 0.
*/
#endif
/* ERROR CODES */
enum STBVorbisError
{
VORBIS__no_error,
VORBIS_need_more_data=1, /* not a real error */
VORBIS_invalid_api_mixing, /* can't mix API modes */
VORBIS_outofmem, /* not enough memory */
VORBIS_feature_not_supported, /* uses floor 0 */
VORBIS_too_many_channels, /* STB_VORBIS_MAX_CHANNELS is too small */
VORBIS_file_open_failure, /* fopen() failed */
VORBIS_seek_without_length, /* can't seek in unknown-length file */
VORBIS_unexpected_eof=10, /* file is truncated? */
VORBIS_seek_invalid, /* seek past EOF */
/* decoding errors (corrupt/invalid stream) -- you probably
* don't care about the exact details of these */
/* vorbis errors: */
VORBIS_invalid_setup=20,
VORBIS_invalid_stream,
/* ogg errors: */
VORBIS_missing_capture_pattern=30,
VORBIS_invalid_stream_structure_version,
VORBIS_continued_packet_flag_invalid,
VORBIS_incorrect_stream_serial_number,
VORBIS_invalid_first_page,
VORBIS_bad_packet_type,
VORBIS_cant_find_last_page,
VORBIS_seek_failed
};
#ifdef __cplusplus
}
#endif
#endif /* STB_VORBIS_INCLUDE_STB_VORBIS_H */
#ifndef STB_VORBIS_HEADER_ONLY
/* global configuration settings (e.g. set these in the project/makefile),
* or just set them in this file at the top (although ideally the first few
* should be visible when the header file is compiled too, although it's not
* crucial)
*/
/* STB_VORBIS_NO_PULLDATA_API
* does not compile the code for the non-pushdata APIs
*/
#if 0
#define STB_VORBIS_NO_PULLDATA_API
#endif
/* STB_VORBIS_MAX_CHANNELS [number]
* globally define this to the maximum number of channels you need.
* The spec does not put a restriction on channels except that
* the count is stored in a byte, so 255 is the hard limit.
* Reducing this saves about 16 bytes per value, so using 16 saves
* (255-16)*16 or around 4KB. Plus anything other memory usage
* I forgot to account for. Can probably go as low as 8 (7.1 audio),
* 6 (5.1 audio), or 2 (stereo only).
*/
#ifndef STB_VORBIS_MAX_CHANNELS
#define STB_VORBIS_MAX_CHANNELS 16 /* enough for anyone? */
#endif
/* STB_VORBIS_FAST_HUFFMAN_LENGTH [number]
* sets the log size of the huffman-acceleration table. Maximum
* supported value is 24. with larger numbers, more decodings are O(1),
* but the table size is larger so worse cache missing, so you'll have
* to probe (and try multiple ogg vorbis files) to find the sweet spot.
*/
#ifndef STB_VORBIS_FAST_HUFFMAN_LENGTH
#define STB_VORBIS_FAST_HUFFMAN_LENGTH 10
#endif
/* STB_VORBIS_FAST_BINARY_LENGTH [number]
* sets the log size of the binary-search acceleration table. this
* is used in similar fashion to the fast-huffman size to set initial
* parameters for the binary search
* STB_VORBIS_FAST_HUFFMAN_INT
* The fast huffman tables are much more efficient if they can be
* stored as 16-bit results instead of 32-bit results. This restricts
* the codebooks to having only 65535 possible outcomes, though.
* (At least, accelerated by the huffman table.)
*/
#ifndef STB_VORBIS_FAST_HUFFMAN_INT
#define STB_VORBIS_FAST_HUFFMAN_SHORT
#endif
/* STB_VORBIS_NO_HUFFMAN_BINARY_SEARCH
* If the 'fast huffman' search doesn't succeed, then stb_vorbis falls
* back on binary searching for the correct one. This requires storing
* extra tables with the huffman codes in sorted order. Defining this
* symbol trades off space for speed by forcing a linear search in the
* non-fast case, except for "sparse" codebooks.
*/
#if 0
#define STB_VORBIS_NO_HUFFMAN_BINARY_SEARCH
#endif
/* STB_VORBIS_CODEBOOK_SHORTS
* The vorbis file format encodes VQ codebook floats as ax+b where a and
* b are floating point per-codebook constants, and x is a 16-bit int.
* Normally, stb_vorbis decodes them to floats rather than leaving them
* as 16-bit ints and computing ax+b while decoding. This is a speed/space
* tradeoff; you can save space by defining this flag.
*/
#ifndef STB_VORBIS_CODEBOOK_SHORTS
#define STB_VORBIS_CODEBOOK_FLOATS
#endif
#include <retro_inline.h>
#define MAX_BLOCKSIZE_LOG 13 /* from specification */
#define MAX_BLOCKSIZE (1 << MAX_BLOCKSIZE_LOG)
#ifndef TRUE
#define TRUE 1
#define FALSE 0
#endif
#ifdef STB_VORBIS_CODEBOOK_FLOATS
typedef float stb_vorbis_codetype;
#else
typedef uint16_t stb_vorbis_codetype;
#endif
/* @NOTE
*
* Some arrays below are tagged "//varies", which means it's actually
* a variable-sized piece of data, but rather than malloc I assume it's
* small enough it's better to just allocate it all together with the
* main thing
*
* Most of the variables are specified with the smallest size I could pack
* them into. It might give better performance to make them all full-sized
* integers. It should be safe to freely rearrange the structures or change
* the sizes larger--nothing relies on silently truncating etc., nor the
* order of variables.
*/
#define FAST_HUFFMAN_TABLE_SIZE (1 << STB_VORBIS_FAST_HUFFMAN_LENGTH)
#define FAST_HUFFMAN_TABLE_MASK (FAST_HUFFMAN_TABLE_SIZE - 1)
typedef struct
{
int dimensions, entries;
uint8_t *codeword_lengths;
float minimum_value;
float delta_value;
uint8_t value_bits;
uint8_t lookup_type;
uint8_t sequence_p;
uint8_t sparse;
uint32_t lookup_values;
stb_vorbis_codetype *multiplicands;
uint32_t *codewords;
#ifdef STB_VORBIS_FAST_HUFFMAN_SHORT
int16_t fast_huffman[FAST_HUFFMAN_TABLE_SIZE];
#else
int32_t fast_huffman[FAST_HUFFMAN_TABLE_SIZE];
#endif
uint32_t *sorted_codewords;
int *sorted_values;
int sorted_entries;
} Codebook;
typedef struct
{
uint8_t order;
uint16_t rate;
uint16_t bark_map_size;
uint8_t amplitude_bits;
uint8_t amplitude_offset;
uint8_t number_of_books;
uint8_t book_list[16]; /* varies */
} Floor0;
typedef struct
{
uint8_t partitions;
uint8_t partition_class_list[32]; /* varies */
uint8_t class_dimensions[16]; /* varies */
uint8_t class_subclasses[16]; /* varies */
uint8_t class_masterbooks[16]; /* varies */
int16_t subclass_books[16][8]; /* varies */
uint16_t Xlist[31*8+2]; /* varies */
uint8_t sorted_order[31*8+2];
uint8_t neighbors[31*8+2][2];
uint8_t floor1_multiplier;
uint8_t rangebits;
int values;
} Floor1;
typedef union
{
Floor0 floor0;
Floor1 floor1;
} Floor;
typedef struct
{
uint32_t begin, end;
uint32_t part_size;
uint8_t classifications;
uint8_t classbook;
uint8_t **classdata;
int16_t (*residue_books)[8];
} Residue;
typedef struct
{
uint8_t magnitude;
uint8_t angle;
uint8_t mux;
} MappingChannel;
typedef struct
{
uint16_t coupling_steps;
MappingChannel *chan;
uint8_t submaps;
uint8_t submap_floor[15]; /* varies */
uint8_t submap_residue[15]; /* varies */
} Mapping;
typedef struct
{
uint8_t blockflag;
uint8_t mapping;
uint16_t windowtype;
uint16_t transformtype;
} Mode;
typedef struct
{
uint32_t goal_crc; /* expected crc if match */
int bytes_left; /* bytes left in packet */
uint32_t crc_so_far; /* running crc */
int bytes_done; /* bytes processed in _current_ chunk */
uint32_t sample_loc; /* granule pos encoded in page */
} CRCscan;
typedef struct
{
uint32_t page_start, page_end;
uint32_t after_previous_page_start;
uint32_t first_decoded_sample;
uint32_t last_decoded_sample;
} ProbedPage;
struct stb_vorbis
{
/* user-accessible info */
unsigned int sample_rate;
int channels;
unsigned int setup_memory_required;
unsigned int temp_memory_required;
unsigned int setup_temp_memory_required;
uint8_t *stream;
uint8_t *stream_start;
uint8_t *stream_end;
uint32_t stream_len;
uint8_t push_mode;
uint32_t first_audio_page_offset;
ProbedPage p_first, p_last;
/* memory management */
stb_vorbis_alloc alloc;
int setup_offset;
int temp_offset;
/* run-time results */
int eof;
enum STBVorbisError error;
/* user-useful data */
/* header info */
int blocksize[2];
int blocksize_0, blocksize_1;
int codebook_count;
Codebook *codebooks;
int floor_count;
uint16_t floor_types[64]; /* varies */
Floor *floor_config;
int residue_count;
uint16_t residue_types[64]; /* varies */
Residue *residue_config;
int mapping_count;
Mapping *mapping;
int mode_count;
Mode mode_config[64]; /* varies */
uint32_t total_samples;
/* decode buffer */
float *channel_buffers[STB_VORBIS_MAX_CHANNELS];
float *outputs [STB_VORBIS_MAX_CHANNELS];
float *previous_window[STB_VORBIS_MAX_CHANNELS];
int previous_length;
int16_t *finalY[STB_VORBIS_MAX_CHANNELS];
uint32_t current_loc; /* sample location of next frame to decode */
int current_loc_valid;
/* per-blocksize precomputed data */
/* twiddle factors */
float *A[2],*B[2],*C[2];
float *window[2];
uint16_t *bit_reverse[2];
/* current page/packet/segment streaming info */
uint32_t serial; /* stream serial number for verification */
int last_page;
int segment_count;
uint8_t segments[255];
uint8_t page_flag;
uint8_t bytes_in_seg;
uint8_t first_decode;
int next_seg;
int last_seg; /* flag that we're on the last segment */
int last_seg_which; /* what was the segment number of the last seg? */
uint32_t acc;
int valid_bits;
int packet_bytes;
int end_seg_with_known_loc;
uint32_t known_loc_for_packet;
int discard_samples_deferred;
uint32_t samples_output;
/* push mode scanning */
int page_crc_tests; /* only in push_mode: number of tests active; -1 if not searching */
/* sample-access */
int channel_buffer_start;
int channel_buffer_end;
};
#define IS_PUSH_MODE(f) FALSE
typedef struct stb_vorbis vorb;
static int error(vorb *f, enum STBVorbisError e)
{
f->error = e;
if (!f->eof && e != VORBIS_need_more_data) {
f->error=e; /* breakpoint for debugging */
}
return 0;
}
/* these functions are used for allocating temporary memory
* while decoding. if you can afford the stack space, use
* alloca(); otherwise, provide a temp buffer and it will
* allocate out of those.
*/
#define array_size_required(count,size) (count*(sizeof(void *)+(size)))
#define temp_alloc(f,size) (f->alloc.alloc_buffer ? setup_temp_malloc(f,size) : alloca(size))
#define temp_alloc_save(f) ((f)->temp_offset)
#define temp_alloc_restore(f,p) ((f)->temp_offset = (p))
#define temp_block_array(f,count,size) make_block_array(temp_alloc(f,array_size_required(count,size)), count, size)
/* given a sufficiently large block of memory, make an array of pointers to subblocks of it */
static void *make_block_array(void *mem, int count, int size)
{
int i;
void ** p = (void **) mem;
char *q = (char *) (p + count);
for (i=0; i < count; ++i) {
p[i] = q;
q += size;
}
return p;
}
static void *setup_malloc(vorb *f, int sz)
{
sz = (sz+3) & ~3;
f->setup_memory_required += sz;
if (f->alloc.alloc_buffer) {
void *p = (char *) f->alloc.alloc_buffer + f->setup_offset;
if (f->setup_offset + sz > f->temp_offset) return NULL;
f->setup_offset += sz;
return p;
}
return sz ? malloc(sz) : NULL;
}
static void setup_free(vorb *f, void *p)
{
if (f->alloc.alloc_buffer) return; /* do nothing; setup mem is not a stack */
free(p);
}
static void *setup_temp_malloc(vorb *f, int sz)
{
sz = (sz+3) & ~3;
if (f->alloc.alloc_buffer) {
if (f->temp_offset - sz < f->setup_offset) return NULL;
f->temp_offset -= sz;
return (char *) f->alloc.alloc_buffer + f->temp_offset;
}
return malloc(sz);
}
static void setup_temp_free(vorb *f, void *p, int sz)
{
if (f->alloc.alloc_buffer) {
f->temp_offset += (sz+3)&~3;
return;
}
free(p);
}
#define CRC32_POLY 0x04c11db7 /* from spec */
static uint32_t stb_vorbis_crc_table[256];
static void crc32_init(void)
{
int i,j;
uint32_t s;
for(i=0; i < 256; i++) {
for (s=i<<24, j=0; j < 8; ++j)
s = (s << 1) ^ (s >= (1U<<31) ? CRC32_POLY : 0);
stb_vorbis_crc_table[i] = s;
}
}
static INLINE uint32_t crc32_update(uint32_t crc, uint8_t byte)
{
return (crc << 8) ^ stb_vorbis_crc_table[byte ^ (crc >> 24)];
}
/* used in setup, and for huffman that doesn't go fast path */
static unsigned int bit_reverse(unsigned int n)
{
n = ((n & 0xAAAAAAAA) >> 1) | ((n & 0x55555555) << 1);
n = ((n & 0xCCCCCCCC) >> 2) | ((n & 0x33333333) << 2);
n = ((n & 0xF0F0F0F0) >> 4) | ((n & 0x0F0F0F0F) << 4);
n = ((n & 0xFF00FF00) >> 8) | ((n & 0x00FF00FF) << 8);
return (n >> 16) | (n << 16);
}
static float square(float x)
{
return x*x;
}
/* this is a weird definition of log2() for which log2(1) = 1, log2(2) = 2, log2(4) = 3
* as required by the specification. fast(?) implementation from stb.h
* @OPTIMIZE: called multiple times per-packet with "constants"; move to setup
*/
static int ilog(int32_t n)
{
static signed char log2_4[16] = { 0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4 };
/* 2 compares if n < 16, 3 compares otherwise (4 if signed or n > 1<<29) */
if (n < (1 << 14))
if (n < (1 << 4)) return 0 + log2_4[n ];
else if (n < (1 << 9)) return 5 + log2_4[n >> 5];
else return 10 + log2_4[n >> 10];
else if (n < (1 << 24))
if (n < (1 << 19)) return 15 + log2_4[n >> 15];
else return 20 + log2_4[n >> 20];
else if (n < (1 << 29)) return 25 + log2_4[n >> 25];
else if (n < (1 << 31)) return 30 + log2_4[n >> 30];
else return 0; /* signed n returns 0 */
}
#ifndef M_PI
#define M_PI 3.14159265358979323846264f /* from CRC */
#endif
/* code length assigned to a value with no huffman encoding */
#define NO_CODE 255
/* LEAF SETUP FUNCTIONS */
/* these functions are only called at setup, and only a few times
* per file */
static float float32_unpack(uint32_t x)
{
/* from the specification */
uint32_t mantissa = x & 0x1fffff;
uint32_t sign = x & 0x80000000;
uint32_t exp = (x & 0x7fe00000) >> 21;
double res = sign ? -(double)mantissa : (double)mantissa;
return (float) ldexp((float)res, exp-788);
}
/* zlib & jpeg huffman tables assume that the output symbols
* can either be arbitrarily arranged, or have monotonically
* increasing frequencies--they rely on the lengths being sorted;
* this makes for a very simple generation algorithm.
* vorbis allows a huffman table with non-sorted lengths. This
* requires a more sophisticated construction, since symbols in
* order do not map to huffman codes "in order".
*/
static void add_entry(Codebook *c, uint32_t huff_code, int symbol, int count, int len, uint32_t *values)
{
if (!c->sparse) {
c->codewords [symbol] = huff_code;
} else {
c->codewords [count] = huff_code;
c->codeword_lengths[count] = len;
values [count] = symbol;
}
}
static int compute_codewords(Codebook *c, uint8_t *len, int n, uint32_t *values)
{
int i,k,m=0;
uint32_t available[32];
memset(available, 0, sizeof(available));
/* find the first entry */
for (k=0; k < n; ++k) if (len[k] < NO_CODE) break;
if (k == n) { assert(c->sorted_entries == 0); return TRUE; }
/* add to the list */
add_entry(c, 0, k, m++, len[k], values);
/* add all available leaves */
for (i=1; i <= len[k]; ++i)
available[i] = 1 << (32-i);
/* note that the above code treats the first case specially,
* but it's really the same as the following code, so they
* could probably be combined (except the initial code is 0,
* and I use 0 in available[] to mean 'empty') */
for (i=k+1; i < n; ++i) {
uint32_t res;
int z = len[i], y;
if (z == NO_CODE) continue;
/* find lowest available leaf (should always be earliest,
* which is what the specification calls for)
* note that this property, and the fact we can never have
* more than one free leaf at a given level, isn't totally
* trivial to prove, but it seems true and the assert never
* fires, so! */
while (z > 0 && !available[z]) --z;
if (z == 0) { assert(0); return FALSE; }
res = available[z];
available[z] = 0;
add_entry(c, bit_reverse(res), i, m++, len[i], values);
/* propogate availability up the tree */
if (z != len[i]) {
for (y=len[i]; y > z; --y) {
assert(available[y] == 0);
available[y] = res + (1 << (32-y));
}
}
}
return TRUE;
}
/* accelerated huffman table allows fast O(1) match of all symbols
* of length <= STB_VORBIS_FAST_HUFFMAN_LENGTH */
static void compute_accelerated_huffman(Codebook *c)
{
int i, len;
for (i=0; i < FAST_HUFFMAN_TABLE_SIZE; ++i)
c->fast_huffman[i] = -1;
len = c->sparse ? c->sorted_entries : c->entries;
#ifdef STB_VORBIS_FAST_HUFFMAN_SHORT
if (len > 32767) len = 32767; /* largest possible value we can encode! */
#endif
for (i=0; i < len; ++i) {
if (c->codeword_lengths[i] <= STB_VORBIS_FAST_HUFFMAN_LENGTH) {
uint32_t z = c->sparse ? bit_reverse(c->sorted_codewords[i]) : c->codewords[i];
/* set table entries for all bit combinations in the higher bits */
while (z < FAST_HUFFMAN_TABLE_SIZE) {
c->fast_huffman[z] = i;
z += 1 << c->codeword_lengths[i];
}
}
}
}
#ifdef _MSC_VER
#define STBV_CDECL __cdecl
#else
#define STBV_CDECL
#endif
static int STBV_CDECL uint32_t_compare(const void *p, const void *q)
{
uint32_t x = * (uint32_t *) p;
uint32_t y = * (uint32_t *) q;
return x < y ? -1 : x > y;
}
static int include_in_sort(Codebook *c, uint8_t len)
{
if (c->sparse) { assert(len != NO_CODE); return TRUE; }
if (len == NO_CODE) return FALSE;
if (len > STB_VORBIS_FAST_HUFFMAN_LENGTH) return TRUE;
return FALSE;
}
/* if the fast table above doesn't work, we want to binary
* search them... need to reverse the bits */
static void compute_sorted_huffman(Codebook *c, uint8_t *lengths, uint32_t *values)
{
int i, len;
/* build a list of all the entries
* OPTIMIZATION: don't include the short ones, since they'll be caught by FAST_HUFFMAN.
* this is kind of a frivolous optimization--I don't see any performance improvement,
* but it's like 4 extra lines of code, so. */
if (!c->sparse) {
int k = 0;
for (i=0; i < c->entries; ++i)
if (include_in_sort(c, lengths[i]))
c->sorted_codewords[k++] = bit_reverse(c->codewords[i]);
assert(k == c->sorted_entries);
} else {
for (i=0; i < c->sorted_entries; ++i)
c->sorted_codewords[i] = bit_reverse(c->codewords[i]);
}
qsort(c->sorted_codewords, c->sorted_entries, sizeof(c->sorted_codewords[0]), uint32_t_compare);
c->sorted_codewords[c->sorted_entries] = 0xffffffff;
len = c->sparse ? c->sorted_entries : c->entries;
/* now we need to indicate how they correspond; we could either
* #1: sort a different data structure that says who they correspond to
* #2: for each sorted entry, search the original list to find who corresponds
* #3: for each original entry, find the sorted entry
* #1 requires extra storage, #2 is slow, #3 can use binary search! */
for (i=0; i < len; ++i) {
int huff_len = c->sparse ? lengths[values[i]] : lengths[i];
if (include_in_sort(c,huff_len)) {
uint32_t code = bit_reverse(c->codewords[i]);
int x=0, n=c->sorted_entries;
while (n > 1) {
/* invariant: sc[x] <= code < sc[x+n] */
int m = x + (n >> 1);
if (c->sorted_codewords[m] <= code) {
x = m;
n -= (n>>1);
} else {
n >>= 1;
}
}
assert(c->sorted_codewords[x] == code);
if (c->sparse) {
c->sorted_values[x] = values[i];
c->codeword_lengths[x] = huff_len;
} else {
c->sorted_values[x] = i;
}
}
}
}
/* only run while parsing the header (3 times) */
static int vorbis_validate(uint8_t *data)
{
static uint8_t vorbis[6] = { 'v', 'o', 'r', 'b', 'i', 's' };
return memcmp(data, vorbis, 6) == 0;
}
/* called from setup only, once per code book
* (formula implied by specification) */
static int lookup1_values(int entries, int dim)
{
int r = (int) floor(exp((float) log((float) entries) / dim));
if ((int) floor(pow((float) r+1, dim)) <= entries) /* (int) cast for MinGW warning; */
++r; /* floor() to avoid _ftol() when non-CRT */
assert(pow((float) r+1, dim) > entries);
assert((int) floor(pow((float) r, dim)) <= entries); /* (int),floor() as above */
return r;
}
/* called twice per file */
static void compute_twiddle_factors(int n, float *A, float *B, float *C)
{
int n4 = n >> 2, n8 = n >> 3;
int k,k2;
for (k=k2=0; k < n4; ++k,k2+=2) {
A[k2 ] = (float) cos(4*k*M_PI/n);
A[k2+1] = (float) -sin(4*k*M_PI/n);
B[k2 ] = (float) cos((k2+1)*M_PI/n/2) * 0.5f;
B[k2+1] = (float) sin((k2+1)*M_PI/n/2) * 0.5f;
}
for (k=k2=0; k < n8; ++k,k2+=2) {
C[k2 ] = (float) cos(2*(k2+1)*M_PI/n);
C[k2+1] = (float) -sin(2*(k2+1)*M_PI/n);
}
}
static void compute_window(int n, float *window)
{
int n2 = n >> 1, i;
for (i=0; i < n2; ++i)
window[i] = (float) sin(0.5 * M_PI * square((float) sin((i - 0 + 0.5) / n2 * 0.5 * M_PI)));
}
static void compute_bitreverse(int n, uint16_t *rev)
{
int ld = ilog(n) - 1; /* ilog is off-by-one from normal definitions */
int i, n8 = n >> 3;
for (i=0; i < n8; ++i)
rev[i] = (bit_reverse(i) >> (32-ld+3)) << 2;
}
static int init_blocksize(vorb *f, int b, int n)
{
int n2 = n >> 1, n4 = n >> 2, n8 = n >> 3;
f->A[b] = (float *) setup_malloc(f, sizeof(float) * n2);
f->B[b] = (float *) setup_malloc(f, sizeof(float) * n2);
f->C[b] = (float *) setup_malloc(f, sizeof(float) * n4);
if (!f->A[b] || !f->B[b] || !f->C[b]) return error(f, VORBIS_outofmem);
compute_twiddle_factors(n, f->A[b], f->B[b], f->C[b]);
f->window[b] = (float *) setup_malloc(f, sizeof(float) * n2);
if (!f->window[b]) return error(f, VORBIS_outofmem);
compute_window(n, f->window[b]);
f->bit_reverse[b] = (uint16_t *) setup_malloc(f, sizeof(uint16_t) * n8);
if (!f->bit_reverse[b]) return error(f, VORBIS_outofmem);
compute_bitreverse(n, f->bit_reverse[b]);
return TRUE;
}
static void neighbors(uint16_t *x, int n, int *plow, int *phigh)
{
int low = -1;
int high = 65536;
int i;
for (i=0; i < n; ++i) {
if (x[i] > low && x[i] < x[n]) { *plow = i; low = x[i]; }
if (x[i] < high && x[i] > x[n]) { *phigh = i; high = x[i]; }
}
}
/* this has been repurposed so y is now the original index instead of y */
typedef struct
{
uint16_t x,y;
} STBV_Point;
static int STBV_CDECL point_compare(const void *p, const void *q)
{
STBV_Point *a = (STBV_Point *) p;
STBV_Point *b = (STBV_Point *) q;
return a->x < b->x ? -1 : a->x > b->x;
}
/* END LEAF SETUP FUNCTIONS */
static uint8_t get8(vorb *z)
{
if (z->stream >= z->stream_end) { z->eof = TRUE; return 0; }
return *z->stream++;
}
static uint32_t get32(vorb *f)
{
uint32_t x;
x = get8(f);
x += get8(f) << 8;
x += get8(f) << 16;
x += get8(f) << 24;
return x;
}
static int getn(vorb *z, uint8_t *data, int n)
{
if (z->stream+n > z->stream_end) { z->eof = 1; return 0; }
memcpy(data, z->stream, n);
z->stream += n;
return 1;
}
static void skip(vorb *z, int n)
{
z->stream += n;
if (z->stream >= z->stream_end) z->eof = 1;
return;
}
static int set_file_offset(stb_vorbis *f, unsigned int loc)
{
f->eof = 0;
if (f->stream_start + loc >= f->stream_end || f->stream_start + loc < f->stream_start) {
f->stream = f->stream_end;
f->eof = 1;
return 0;
} else {
f->stream = f->stream_start + loc;
return 1;
}
}
static uint8_t ogg_page_header[4] = { 0x4f, 0x67, 0x67, 0x53 };
static int capture_pattern(vorb *f)
{
if (0x4f != get8(f)) return FALSE;
if (0x67 != get8(f)) return FALSE;
if (0x67 != get8(f)) return FALSE;
if (0x53 != get8(f)) return FALSE;
return TRUE;
}
#define PAGEFLAG_continued_packet 1
#define PAGEFLAG_first_page 2
#define PAGEFLAG_last_page 4
static int start_page_no_capturepattern(vorb *f)
{
uint32_t loc0,loc1,n;
/* stream structure version */
if (0 != get8(f)) return error(f, VORBIS_invalid_stream_structure_version);
/* header flag */
f->page_flag = get8(f);
/* absolute granule position */
loc0 = get32(f);
loc1 = get32(f);
/* @TODO: validate loc0,loc1 as valid positions?
* stream serial number -- vorbis doesn't interleave, so discard */
get32(f);
/*if (f->serial != get32(f)) return error(f, VORBIS_incorrect_stream_serial_number);
* page sequence number */
n = get32(f);
f->last_page = n;
/* CRC32 */
get32(f);
/* page_segments */
f->segment_count = get8(f);
if (!getn(f, f->segments, f->segment_count))
return error(f, VORBIS_unexpected_eof);
/* assume we _don't_ know any the sample position of any segments */
f->end_seg_with_known_loc = -2;
if (loc0 != ~0U || loc1 != ~0U) {
int i;
/* determine which packet is the last one that will complete */
for (i=f->segment_count-1; i >= 0; --i)
if (f->segments[i] < 255)
break;
/* 'i' is now the index of the _last_ segment of a packet that ends */
if (i >= 0) {
f->end_seg_with_known_loc = i;
f->known_loc_for_packet = loc0;
}
}
if (f->first_decode) {
int i,len;
ProbedPage p;
len = 0;
for (i=0; i < f->segment_count; ++i)
len += f->segments[i];
len += 27 + f->segment_count;
p.page_start = f->first_audio_page_offset;
p.page_end = p.page_start + len;
p.after_previous_page_start = p.page_start;
p.first_decoded_sample = 0;
p.last_decoded_sample = loc0;
f->p_first = p;
}
f->next_seg = 0;
return TRUE;
}
static int start_page(vorb *f)
{
if (!capture_pattern(f)) return error(f, VORBIS_missing_capture_pattern);
return start_page_no_capturepattern(f);
}
static int start_packet(vorb *f)
{
while (f->next_seg == -1) {
if (!start_page(f)) return FALSE;
if (f->page_flag & PAGEFLAG_continued_packet)
return error(f, VORBIS_continued_packet_flag_invalid);
}
f->last_seg = FALSE;
f->valid_bits = 0;
f->packet_bytes = 0;
f->bytes_in_seg = 0;
/* f->next_seg is now valid */
return TRUE;
}
static int maybe_start_packet(vorb *f)
{
if (f->next_seg == -1) {
int x = get8(f);
if (f->eof) return FALSE; /* EOF at page boundary is not an error! */
if (0x4f != x ) return error(f, VORBIS_missing_capture_pattern);
if (0x67 != get8(f)) return error(f, VORBIS_missing_capture_pattern);
if (0x67 != get8(f)) return error(f, VORBIS_missing_capture_pattern);
if (0x53 != get8(f)) return error(f, VORBIS_missing_capture_pattern);
if (!start_page_no_capturepattern(f)) return FALSE;
if (f->page_flag & PAGEFLAG_continued_packet) {
/* set up enough state that we can read this packet if we want,
* e.g. during recovery */
f->last_seg = FALSE;
f->bytes_in_seg = 0;
return error(f, VORBIS_continued_packet_flag_invalid);
}
}
return start_packet(f);
}
static int next_segment(vorb *f)
{
int len;
if (f->last_seg) return 0;
if (f->next_seg == -1) {
f->last_seg_which = f->segment_count-1; /* in case start_page fails */
if (!start_page(f)) { f->last_seg = 1; return 0; }
if (!(f->page_flag & PAGEFLAG_continued_packet)) return error(f, VORBIS_continued_packet_flag_invalid);
}
len = f->segments[f->next_seg++];
if (len < 255) {
f->last_seg = TRUE;
f->last_seg_which = f->next_seg-1;
}
if (f->next_seg >= f->segment_count)
f->next_seg = -1;
assert(f->bytes_in_seg == 0);
f->bytes_in_seg = len;
return len;
}
#define EOP (-1)
#define INVALID_BITS (-1)
static int get8_packet_raw(vorb *f)
{
if (!f->bytes_in_seg) { /* CLANG! */
if (f->last_seg) return EOP;
else if (!next_segment(f)) return EOP;
}
assert(f->bytes_in_seg > 0);
--f->bytes_in_seg;
++f->packet_bytes;
return get8(f);
}
static int get8_packet(vorb *f)
{
int x = get8_packet_raw(f);
f->valid_bits = 0;
return x;
}
static void flush_packet(vorb *f)
{
while (get8_packet_raw(f) != EOP);
}
/* @OPTIMIZE: this is the secondary bit decoder, so it's probably not as important
* as the huffman decoder? */
static uint32_t get_bits(vorb *f, int n)
{
uint32_t z;
if (f->valid_bits < 0) return 0;
if (f->valid_bits < n) {
if (n > 24) {
/* the accumulator technique below would not work correctly in this case */
z = get_bits(f, 24);
z += get_bits(f, n-24) << 24;
return z;
}
if (f->valid_bits == 0) f->acc = 0;
while (f->valid_bits < n) {
int z = get8_packet_raw(f);
if (z == EOP) {
f->valid_bits = INVALID_BITS;
return 0;
}
f->acc += z << f->valid_bits;
f->valid_bits += 8;
}
}
if (f->valid_bits < 0) return 0;
z = f->acc & ((1 << n)-1);
f->acc >>= n;
f->valid_bits -= n;
return z;
}
/* @OPTIMIZE: primary accumulator for huffman
* expand the buffer to as many bits as possible without reading off end of packet
* it might be nice to allow f->valid_bits and f->acc to be stored in registers,
* e.g. cache them locally and decode locally */
static INLINE void prep_huffman(vorb *f)
{
if (f->valid_bits <= 24) {
if (f->valid_bits == 0) f->acc = 0;
do {
int z;
if (f->last_seg && !f->bytes_in_seg) return;
z = get8_packet_raw(f);
if (z == EOP) return;
f->acc += z << f->valid_bits;
f->valid_bits += 8;
} while (f->valid_bits <= 24);
}
}
enum
{
VORBIS_packet_id = 1,
VORBIS_packet_comment = 3,
VORBIS_packet_setup = 5
};
static int codebook_decode_scalar_raw(vorb *f, Codebook *c)
{
int i;
prep_huffman(f);
assert(c->sorted_codewords || c->codewords);
/* cases to use binary search: sorted_codewords && !c->codewords
* sorted_codewords && c->entries > 8 */
if (c->entries > 8 ? c->sorted_codewords!=NULL : !c->codewords) {
/* binary search */
uint32_t code = bit_reverse(f->acc);
int x=0, n=c->sorted_entries, len;
while (n > 1) {
/* invariant: sc[x] <= code < sc[x+n] */
int m = x + (n >> 1);
if (c->sorted_codewords[m] <= code) {
x = m;
n -= (n>>1);
} else {
n >>= 1;
}
}
/* x is now the sorted index */
if (!c->sparse) x = c->sorted_values[x];
/* x is now sorted index if sparse, or symbol otherwise */
len = c->codeword_lengths[x];
if (f->valid_bits >= len) {
f->acc >>= len;
f->valid_bits -= len;
return x;
}
f->valid_bits = 0;
return -1;
}
/* if small, linear search */
assert(!c->sparse);
for (i=0; i < c->entries; ++i) {
if (c->codeword_lengths[i] == NO_CODE) continue;
if (c->codewords[i] == (f->acc & ((1 << c->codeword_lengths[i])-1))) {
if (f->valid_bits >= c->codeword_lengths[i]) {
f->acc >>= c->codeword_lengths[i];
f->valid_bits -= c->codeword_lengths[i];
return i;
}
f->valid_bits = 0;
return -1;
}
}
error(f, VORBIS_invalid_stream);
f->valid_bits = 0;
return -1;
}
static int codebook_decode_scalar(vorb *f, Codebook *c)
{
int i;
if (f->valid_bits < STB_VORBIS_FAST_HUFFMAN_LENGTH)
prep_huffman(f);
/* fast huffman table lookup */
i = f->acc & FAST_HUFFMAN_TABLE_MASK;
i = c->fast_huffman[i];
if (i >= 0) {
f->acc >>= c->codeword_lengths[i];
f->valid_bits -= c->codeword_lengths[i];
if (f->valid_bits < 0) { f->valid_bits = 0; return -1; }
return i;
}
return codebook_decode_scalar_raw(f,c);
}
#define DECODE_RAW(var,f,c) var = codebook_decode_scalar(f,c);
#define DECODE(var,f,c) \
DECODE_RAW(var,f,c) \
if (c->sparse) var = c->sorted_values[var];
#define DECODE_VQ(var,f,c) DECODE_RAW(var,f,c)
/* CODEBOOK_ELEMENT_FAST is an optimization for the CODEBOOK_FLOATS case
* where we avoid one addition */
#ifndef STB_VORBIS_CODEBOOK_FLOATS
#define CODEBOOK_ELEMENT(c,off) (c->multiplicands[off] * c->delta_value + c->minimum_value)
#define CODEBOOK_ELEMENT_FAST(c,off) (c->multiplicands[off] * c->delta_value)
#define CODEBOOK_ELEMENT_BASE(c) (c->minimum_value)
#else
#define CODEBOOK_ELEMENT(c,off) (c->multiplicands[off])
#define CODEBOOK_ELEMENT_FAST(c,off) (c->multiplicands[off])
#define CODEBOOK_ELEMENT_BASE(c) (0)
#endif
static int codebook_decode_start(vorb *f, Codebook *c)
{
int z = -1;
/* type 0 is only legal in a scalar context */
if (c->lookup_type == 0)
error(f, VORBIS_invalid_stream);
else {
DECODE_VQ(z,f,c);
if (c->sparse) assert(z < c->sorted_entries);
if (z < 0) { /* check for EOP */
if (!f->bytes_in_seg)
if (f->last_seg)
return z;
error(f, VORBIS_invalid_stream);
}
}
return z;
}
static int codebook_decode(vorb *f, Codebook *c, float *output, int len)
{
int i,z = codebook_decode_start(f,c);
if (z < 0) return FALSE;
if (len > c->dimensions) len = c->dimensions;
z *= c->dimensions;
if (c->sequence_p) {
float last = CODEBOOK_ELEMENT_BASE(c);
for (i=0; i < len; ++i) {
float val = CODEBOOK_ELEMENT_FAST(c,z+i) + last;
output[i] += val;
last = val + c->minimum_value;
}
} else {
float last = CODEBOOK_ELEMENT_BASE(c);
for (i=0; i < len; ++i) {
output[i] += CODEBOOK_ELEMENT_FAST(c,z+i) + last;
}
}
return TRUE;
}
static int codebook_decode_step(vorb *f, Codebook *c, float *output, int len, int step)
{
int i,z = codebook_decode_start(f,c);
float last = CODEBOOK_ELEMENT_BASE(c);
if (z < 0) return FALSE;
if (len > c->dimensions) len = c->dimensions;
z *= c->dimensions;
for (i=0; i < len; ++i) {
float val = CODEBOOK_ELEMENT_FAST(c,z+i) + last;
output[i*step] += val;
if (c->sequence_p) last = val;
}
return TRUE;
}
static int codebook_decode_deinterleave_repeat(vorb *f, Codebook *c, float **outputs, int ch, int *c_inter_p, int *p_inter_p, int len, int total_decode)
{
int c_inter = *c_inter_p;
int p_inter = *p_inter_p;
int i,z, effective = c->dimensions;
/* type 0 is only legal in a scalar context */
if (c->lookup_type == 0) return error(f, VORBIS_invalid_stream);
while (total_decode > 0) {
float last = CODEBOOK_ELEMENT_BASE(c);
DECODE_VQ(z,f,c);
assert(!c->sparse || z < c->sorted_entries);
if (z < 0) {
if (!f->bytes_in_seg)
if (f->last_seg) return FALSE;
return error(f, VORBIS_invalid_stream);
}
/* if this will take us off the end of the buffers, stop short!
* we check by computing the length of the virtual interleaved
* buffer (len*ch), our current offset within it (p_inter*ch)+(c_inter),
* and the length we'll be using (effective) */
if (c_inter + p_inter*ch + effective > len * ch) {
effective = len*ch - (p_inter*ch - c_inter);
}
z *= c->dimensions;
if (c->sequence_p) {
for (i=0; i < effective; ++i) {
float val = CODEBOOK_ELEMENT_FAST(c,z+i) + last;
if (outputs[c_inter])
outputs[c_inter][p_inter] += val;
if (++c_inter == ch) { c_inter = 0; ++p_inter; }
last = val;
}
} else {
for (i=0; i < effective; ++i) {
float val = CODEBOOK_ELEMENT_FAST(c,z+i) + last;
if (outputs[c_inter])
outputs[c_inter][p_inter] += val;
if (++c_inter == ch) { c_inter = 0; ++p_inter; }
}
}
total_decode -= effective;
}
*c_inter_p = c_inter;
*p_inter_p = p_inter;
return TRUE;
}
static int codebook_decode_deinterleave_repeat_2(vorb *f, Codebook *c, float **outputs, int *c_inter_p, int *p_inter_p, int len, int total_decode)
{
int c_inter = *c_inter_p;
int p_inter = *p_inter_p;
int i,z, effective = c->dimensions;
/* type 0 is only legal in a scalar context */
if (c->lookup_type == 0) return error(f, VORBIS_invalid_stream);
while (total_decode > 0) {
float last = CODEBOOK_ELEMENT_BASE(c);
DECODE_VQ(z,f,c);
if (z < 0) {
if (!f->bytes_in_seg)
if (f->last_seg) return FALSE;
return error(f, VORBIS_invalid_stream);
}
/* if this will take us off the end of the buffers, stop short!
* we check by computing the length of the virtual interleaved
* buffer (len*ch), our current offset within it (p_inter*ch)+(c_inter),
* and the length we'll be using (effective)
*/
if (c_inter + p_inter*2 + effective > len * 2) {
effective = len*2 - (p_inter*2 - c_inter);
}
{
z *= c->dimensions;
if (c->sequence_p) {
/* haven't optimized this case because I don't have any examples */
for (i=0; i < effective; ++i) {
float val = CODEBOOK_ELEMENT_FAST(c,z+i) + last;
if (outputs[c_inter])
outputs[c_inter][p_inter] += val;
if (++c_inter == 2) { c_inter = 0; ++p_inter; }
last = val;
}
} else {
i=0;
if (c_inter == 1) {
float val = CODEBOOK_ELEMENT_FAST(c,z+i) + last;
if (outputs[c_inter])
outputs[c_inter][p_inter] += val;
c_inter = 0; ++p_inter;
++i;
}
{
float *z0 = outputs[0];
float *z1 = outputs[1];
for (; i+1 < effective;) {
float v0 = CODEBOOK_ELEMENT_FAST(c,z+i) + last;
float v1 = CODEBOOK_ELEMENT_FAST(c,z+i+1) + last;
if (z0)
z0[p_inter] += v0;
if (z1)
z1[p_inter] += v1;
++p_inter;
i += 2;
}
}
if (i < effective) {
float val = CODEBOOK_ELEMENT_FAST(c,z+i) + last;
if (outputs[c_inter])
outputs[c_inter][p_inter] += val;
if (++c_inter == 2) { c_inter = 0; ++p_inter; }
}
}
}
total_decode -= effective;
}
*c_inter_p = c_inter;
*p_inter_p = p_inter;
return TRUE;
}
static int predict_point(int x, int x0, int x1, int y0, int y1)
{
int dy = y1 - y0;
int adx = x1 - x0;
/* @OPTIMIZE: force int division to round in the right direction... is this necessary on x86? */
int err = abs(dy) * (x - x0);
int off = err / adx;
return dy < 0 ? y0 - off : y0 + off;
}
/* the following table is block-copied from the specification */
static float inverse_db_table[256] =
{
1.0649863e-07f, 1.1341951e-07f, 1.2079015e-07f, 1.2863978e-07f,
1.3699951e-07f, 1.4590251e-07f, 1.5538408e-07f, 1.6548181e-07f,
1.7623575e-07f, 1.8768855e-07f, 1.9988561e-07f, 2.1287530e-07f,
2.2670913e-07f, 2.4144197e-07f, 2.5713223e-07f, 2.7384213e-07f,
2.9163793e-07f, 3.1059021e-07f, 3.3077411e-07f, 3.5226968e-07f,
3.7516214e-07f, 3.9954229e-07f, 4.2550680e-07f, 4.5315863e-07f,
4.8260743e-07f, 5.1396998e-07f, 5.4737065e-07f, 5.8294187e-07f,
6.2082472e-07f, 6.6116941e-07f, 7.0413592e-07f, 7.4989464e-07f,
7.9862701e-07f, 8.5052630e-07f, 9.0579828e-07f, 9.6466216e-07f,
1.0273513e-06f, 1.0941144e-06f, 1.1652161e-06f, 1.2409384e-06f,
1.3215816e-06f, 1.4074654e-06f, 1.4989305e-06f, 1.5963394e-06f,
1.7000785e-06f, 1.8105592e-06f, 1.9282195e-06f, 2.0535261e-06f,
2.1869758e-06f, 2.3290978e-06f, 2.4804557e-06f, 2.6416497e-06f,
2.8133190e-06f, 2.9961443e-06f, 3.1908506e-06f, 3.3982101e-06f,
3.6190449e-06f, 3.8542308e-06f, 4.1047004e-06f, 4.3714470e-06f,
4.6555282e-06f, 4.9580707e-06f, 5.2802740e-06f, 5.6234160e-06f,
5.9888572e-06f, 6.3780469e-06f, 6.7925283e-06f, 7.2339451e-06f,
7.7040476e-06f, 8.2047000e-06f, 8.7378876e-06f, 9.3057248e-06f,
9.9104632e-06f, 1.0554501e-05f, 1.1240392e-05f, 1.1970856e-05f,
1.2748789e-05f, 1.3577278e-05f, 1.4459606e-05f, 1.5399272e-05f,
1.6400004e-05f, 1.7465768e-05f, 1.8600792e-05f, 1.9809576e-05f,
2.1096914e-05f, 2.2467911e-05f, 2.3928002e-05f, 2.5482978e-05f,
2.7139006e-05f, 2.8902651e-05f, 3.0780908e-05f, 3.2781225e-05f,
3.4911534e-05f, 3.7180282e-05f, 3.9596466e-05f, 4.2169667e-05f,
4.4910090e-05f, 4.7828601e-05f, 5.0936773e-05f, 5.4246931e-05f,
5.7772202e-05f, 6.1526565e-05f, 6.5524908e-05f, 6.9783085e-05f,
7.4317983e-05f, 7.9147585e-05f, 8.4291040e-05f, 8.9768747e-05f,
9.5602426e-05f, 0.00010181521f, 0.00010843174f, 0.00011547824f,
0.00012298267f, 0.00013097477f, 0.00013948625f, 0.00014855085f,
0.00015820453f, 0.00016848555f, 0.00017943469f, 0.00019109536f,
0.00020351382f, 0.00021673929f, 0.00023082423f, 0.00024582449f,
0.00026179955f, 0.00027881276f, 0.00029693158f, 0.00031622787f,
0.00033677814f, 0.00035866388f, 0.00038197188f, 0.00040679456f,
0.00043323036f, 0.00046138411f, 0.00049136745f, 0.00052329927f,
0.00055730621f, 0.00059352311f, 0.00063209358f, 0.00067317058f,
0.00071691700f, 0.00076350630f, 0.00081312324f, 0.00086596457f,
0.00092223983f, 0.00098217216f, 0.0010459992f, 0.0011139742f,
0.0011863665f, 0.0012634633f, 0.0013455702f, 0.0014330129f,
0.0015261382f, 0.0016253153f, 0.0017309374f, 0.0018434235f,
0.0019632195f, 0.0020908006f, 0.0022266726f, 0.0023713743f,
0.0025254795f, 0.0026895994f, 0.0028643847f, 0.0030505286f,
0.0032487691f, 0.0034598925f, 0.0036847358f, 0.0039241906f,
0.0041792066f, 0.0044507950f, 0.0047400328f, 0.0050480668f,
0.0053761186f, 0.0057254891f, 0.0060975636f, 0.0064938176f,
0.0069158225f, 0.0073652516f, 0.0078438871f, 0.0083536271f,
0.0088964928f, 0.009474637f, 0.010090352f, 0.010746080f,
0.011444421f, 0.012188144f, 0.012980198f, 0.013823725f,
0.014722068f, 0.015678791f, 0.016697687f, 0.017782797f,
0.018938423f, 0.020169149f, 0.021479854f, 0.022875735f,
0.024362330f, 0.025945531f, 0.027631618f, 0.029427276f,
0.031339626f, 0.033376252f, 0.035545228f, 0.037855157f,
0.040315199f, 0.042935108f, 0.045725273f, 0.048696758f,
0.051861348f, 0.055231591f, 0.058820850f, 0.062643361f,
0.066714279f, 0.071049749f, 0.075666962f, 0.080584227f,
0.085821044f, 0.091398179f, 0.097337747f, 0.10366330f,
0.11039993f, 0.11757434f, 0.12521498f, 0.13335215f,
0.14201813f, 0.15124727f, 0.16107617f, 0.17154380f,
0.18269168f, 0.19456402f, 0.20720788f, 0.22067342f,
0.23501402f, 0.25028656f, 0.26655159f, 0.28387361f,
0.30232132f, 0.32196786f, 0.34289114f, 0.36517414f,
0.38890521f, 0.41417847f, 0.44109412f, 0.46975890f,
0.50028648f, 0.53279791f, 0.56742212f, 0.60429640f,
0.64356699f, 0.68538959f, 0.72993007f, 0.77736504f,
0.82788260f, 0.88168307f, 0.9389798f, 1.0f
};
/* @OPTIMIZE: if you want to replace this bresenham line-drawing routine,
* note that you must produce bit-identical output to decode correctly;
* this specific sequence of operations is specified in the spec (it's
* drawing integer-quantized frequency-space lines that the encoder
* expects to be exactly the same)
* ... also, isn't the whole point of Bresenham's algorithm to NOT
* have to divide in the setup? sigh.
*/
#define LINE_OP(a,b) a *= b
static INLINE void draw_line(float *output, int x0, int y0, int x1, int y1, int n)
{
int dy = y1 - y0;
int adx = x1 - x0;
int ady = abs(dy);
int x=x0,y=y0;
int err = 0;
int sy;
int base = dy / adx;
if (dy < 0)
sy = base - 1;
else
sy = base+1;
ady -= abs(base) * adx;
if (x1 > n) x1 = n;
LINE_OP(output[x], inverse_db_table[y]);
for (++x; x < x1; ++x) {
err += ady;
if (err >= adx) {
err -= adx;
y += sy;
} else
y += base;
LINE_OP(output[x], inverse_db_table[y]);
}
}
static int residue_decode(vorb *f, Codebook *book, float *target, int offset, int n, int rtype)
{
int k;
if (rtype == 0) {
int step = n / book->dimensions;
for (k=0; k < step; ++k)
if (!codebook_decode_step(f, book, target+offset+k, n-offset-k, step))
return FALSE;
} else {
for (k=0; k < n; ) {
if (!codebook_decode(f, book, target+offset, n-k))
return FALSE;
k += book->dimensions;
offset += book->dimensions;
}
}
return TRUE;
}
static void decode_residue(vorb *f, float *residue_buffers[], int ch, int n, int rn, uint8_t *do_not_decode)
{
int i,j,pass;
Residue *r = f->residue_config + rn;
int rtype = f->residue_types[rn];
int c = r->classbook;
int classwords = f->codebooks[c].dimensions;
int n_read = r->end - r->begin;
int part_read = n_read / r->part_size;
int temp_alloc_point = temp_alloc_save(f);
uint8_t ***part_classdata = (uint8_t ***) temp_block_array(f,f->channels, part_read * sizeof(**part_classdata));
for (i=0; i < ch; ++i)
if (!do_not_decode[i])
memset(residue_buffers[i], 0, sizeof(float) * n);
if (rtype == 2 && ch != 1) {
for (j=0; j < ch; ++j)
if (!do_not_decode[j])
break;
if (j == ch)
goto done;
for (pass=0; pass < 8; ++pass) {
int pcount = 0, class_set = 0;
if (ch == 2) {
while (pcount < part_read) {
int z = r->begin + pcount*r->part_size;
int c_inter = (z & 1), p_inter = z>>1;
if (pass == 0) {
Codebook *c = f->codebooks+r->classbook;
int q;
DECODE(q,f,c);
if (q == EOP) goto done;
part_classdata[0][class_set] = r->classdata[q];
}
for (i=0; i < classwords && pcount < part_read; ++i, ++pcount) {
int z = r->begin + pcount*r->part_size;
int c = part_classdata[0][class_set][i];
int b = r->residue_books[c][pass];
if (b >= 0) {
Codebook *book = f->codebooks + b;
/* saves 1% */
if (!codebook_decode_deinterleave_repeat_2(f, book, residue_buffers, &c_inter, &p_inter, n, r->part_size))
goto done;
} else {
z += r->part_size;
c_inter = z & 1;
p_inter = z >> 1;
}
}
++class_set;
}
} else if (ch == 1) {
while (pcount < part_read) {
int z = r->begin + pcount*r->part_size;
int c_inter = 0, p_inter = z;
if (pass == 0) {
Codebook *c = f->codebooks+r->classbook;
int q;
DECODE(q,f,c);
if (q == EOP) goto done;
part_classdata[0][class_set] = r->classdata[q];
}
for (i=0; i < classwords && pcount < part_read; ++i, ++pcount) {
int z = r->begin + pcount*r->part_size;
int c = part_classdata[0][class_set][i];
int b = r->residue_books[c][pass];
if (b >= 0) {
Codebook *book = f->codebooks + b;
if (!codebook_decode_deinterleave_repeat(f, book, residue_buffers, ch, &c_inter, &p_inter, n, r->part_size))
goto done;
} else {
z += r->part_size;
c_inter = 0;
p_inter = z;
}
}
++class_set;
}
} else {
while (pcount < part_read) {
int z = r->begin + pcount*r->part_size;
int c_inter = z % ch, p_inter = z/ch;
if (pass == 0) {
Codebook *c = f->codebooks+r->classbook;
int q;
DECODE(q,f,c);
if (q == EOP) goto done;
part_classdata[0][class_set] = r->classdata[q];
}
for (i=0; i < classwords && pcount < part_read; ++i, ++pcount) {
int z = r->begin + pcount*r->part_size;
int c = part_classdata[0][class_set][i];
int b = r->residue_books[c][pass];
if (b >= 0) {
Codebook *book = f->codebooks + b;
if (!codebook_decode_deinterleave_repeat(f, book, residue_buffers, ch, &c_inter, &p_inter, n, r->part_size))
goto done;
} else {
z += r->part_size;
c_inter = z % ch;
p_inter = z / ch;
}
}
++class_set;
}
}
}
goto done;
}
for (pass=0; pass < 8; ++pass) {
int pcount = 0, class_set=0;
while (pcount < part_read) {
if (pass == 0) {
for (j=0; j < ch; ++j) {
if (!do_not_decode[j]) {
Codebook *c = f->codebooks+r->classbook;
int temp;
DECODE(temp,f,c);
if (temp == EOP) goto done;
part_classdata[j][class_set] = r->classdata[temp];
}
}
}
for (i=0; i < classwords && pcount < part_read; ++i, ++pcount) {
for (j=0; j < ch; ++j) {
if (!do_not_decode[j]) {
int c = part_classdata[j][class_set][i];
int b = r->residue_books[c][pass];
if (b >= 0) {
float *target = residue_buffers[j];
int offset = r->begin + pcount * r->part_size;
int n = r->part_size;
Codebook *book = f->codebooks + b;
if (!residue_decode(f, book, target, offset, n, rtype))
goto done;
}
}
}
}
++class_set;
}
}
done:
temp_alloc_restore(f,temp_alloc_point);
}
#ifndef LIBVORBIS_MDCT
#define LIBVORBIS_MDCT 0
#endif
#if LIBVORBIS_MDCT
/* directly call the vorbis MDCT using an interface documented
* by Jeff Roberts... useful for performance comparison */
typedef struct
{
int n;
int log2n;
float *trig;
int *bitrev;
float scale;
} mdct_lookup;
extern void mdct_init(mdct_lookup *lookup, int n);
extern void mdct_clear(mdct_lookup *l);
extern void mdct_backward(mdct_lookup *init, float *in, float *out);
mdct_lookup M1,M2;
void inverse_mdct(float *buffer, int n, vorb *f, int blocktype)
{
mdct_lookup *M;
if (M1.n == n) M = &M1;
else if (M2.n == n) M = &M2;
else if (M1.n == 0) { mdct_init(&M1, n); M = &M1; }
else {
if (M2.n) __asm int 3;
mdct_init(&M2, n);
M = &M2;
}
mdct_backward(M, buffer, buffer);
}
#endif
/* the following were split out into separate functions while optimizing;
* they could be pushed back up but eh. __forceinline showed no change;
* they're probably already being inlined. */
static void imdct_step3_iter0_loop(int n, float *e, int i_off, int k_off, float *A)
{
float *ee0 = e + i_off;
float *ee2 = ee0 + k_off;
int i;
assert((n & 3) == 0);
for (i=(n>>2); i > 0; --i) {
float k00_20, k01_21;
k00_20 = ee0[ 0] - ee2[ 0];
k01_21 = ee0[-1] - ee2[-1];
ee0[ 0] += ee2[ 0];/*ee0[ 0] = ee0[ 0] + ee2[ 0]; */
ee0[-1] += ee2[-1];/*ee0[-1] = ee0[-1] + ee2[-1]; */
ee2[ 0] = k00_20 * A[0] - k01_21 * A[1];
ee2[-1] = k01_21 * A[0] + k00_20 * A[1];
A += 8;
k00_20 = ee0[-2] - ee2[-2];
k01_21 = ee0[-3] - ee2[-3];
ee0[-2] += ee2[-2];/*ee0[-2] = ee0[-2] + ee2[-2]; */
ee0[-3] += ee2[-3];/*ee0[-3] = ee0[-3] + ee2[-3]; */
ee2[-2] = k00_20 * A[0] - k01_21 * A[1];
ee2[-3] = k01_21 * A[0] + k00_20 * A[1];
A += 8;
k00_20 = ee0[-4] - ee2[-4];
k01_21 = ee0[-5] - ee2[-5];
ee0[-4] += ee2[-4];/*ee0[-4] = ee0[-4] + ee2[-4]; */
ee0[-5] += ee2[-5];/*ee0[-5] = ee0[-5] + ee2[-5]; */
ee2[-4] = k00_20 * A[0] - k01_21 * A[1];
ee2[-5] = k01_21 * A[0] + k00_20 * A[1];
A += 8;
k00_20 = ee0[-6] - ee2[-6];
k01_21 = ee0[-7] - ee2[-7];
ee0[-6] += ee2[-6];/*ee0[-6] = ee0[-6] + ee2[-6]; */
ee0[-7] += ee2[-7];/*ee0[-7] = ee0[-7] + ee2[-7]; */
ee2[-6] = k00_20 * A[0] - k01_21 * A[1];
ee2[-7] = k01_21 * A[0] + k00_20 * A[1];
A += 8;
ee0 -= 8;
ee2 -= 8;
}
}
static void imdct_step3_inner_r_loop(int lim, float *e, int d0, int k_off, float *A, int k1)
{
int i;
float k00_20, k01_21;
float *e0 = e + d0;
float *e2 = e0 + k_off;
for (i=lim >> 2; i > 0; --i) {
k00_20 = e0[-0] - e2[-0];
k01_21 = e0[-1] - e2[-1];
e0[-0] += e2[-0];/*e0[-0] = e0[-0] + e2[-0]; */
e0[-1] += e2[-1];/*e0[-1] = e0[-1] + e2[-1]; */
e2[-0] = (k00_20)*A[0] - (k01_21) * A[1];
e2[-1] = (k01_21)*A[0] + (k00_20) * A[1];
A += k1;
k00_20 = e0[-2] - e2[-2];
k01_21 = e0[-3] - e2[-3];
e0[-2] += e2[-2];/*e0[-2] = e0[-2] + e2[-2]; */
e0[-3] += e2[-3];/*e0[-3] = e0[-3] + e2[-3]; */
e2[-2] = (k00_20)*A[0] - (k01_21) * A[1];
e2[-3] = (k01_21)*A[0] + (k00_20) * A[1];
A += k1;
k00_20 = e0[-4] - e2[-4];
k01_21 = e0[-5] - e2[-5];
e0[-4] += e2[-4];/*e0[-4] = e0[-4] + e2[-4]; */
e0[-5] += e2[-5];/*e0[-5] = e0[-5] + e2[-5]; */
e2[-4] = (k00_20)*A[0] - (k01_21) * A[1];
e2[-5] = (k01_21)*A[0] + (k00_20) * A[1];
A += k1;
k00_20 = e0[-6] - e2[-6];
k01_21 = e0[-7] - e2[-7];
e0[-6] += e2[-6];/*e0[-6] = e0[-6] + e2[-6]; */
e0[-7] += e2[-7];/*e0[-7] = e0[-7] + e2[-7]; */
e2[-6] = (k00_20)*A[0] - (k01_21) * A[1];
e2[-7] = (k01_21)*A[0] + (k00_20) * A[1];
e0 -= 8;
e2 -= 8;
A += k1;
}
}
static void imdct_step3_inner_s_loop(int n, float *e, int i_off, int k_off, float *A, int a_off, int k0)
{
int i;
float A0 = A[0];
float A1 = A[0+1];
float A2 = A[0+a_off];
float A3 = A[0+a_off+1];
float A4 = A[0+a_off*2+0];
float A5 = A[0+a_off*2+1];
float A6 = A[0+a_off*3+0];
float A7 = A[0+a_off*3+1];
float k00,k11;
float *ee0 = e +i_off;
float *ee2 = ee0+k_off;
for (i=n; i > 0; --i) {
k00 = ee0[ 0] - ee2[ 0];
k11 = ee0[-1] - ee2[-1];
ee0[ 0] = ee0[ 0] + ee2[ 0];
ee0[-1] = ee0[-1] + ee2[-1];
ee2[ 0] = (k00) * A0 - (k11) * A1;
ee2[-1] = (k11) * A0 + (k00) * A1;
k00 = ee0[-2] - ee2[-2];
k11 = ee0[-3] - ee2[-3];
ee0[-2] = ee0[-2] + ee2[-2];
ee0[-3] = ee0[-3] + ee2[-3];
ee2[-2] = (k00) * A2 - (k11) * A3;
ee2[-3] = (k11) * A2 + (k00) * A3;
k00 = ee0[-4] - ee2[-4];
k11 = ee0[-5] - ee2[-5];
ee0[-4] = ee0[-4] + ee2[-4];
ee0[-5] = ee0[-5] + ee2[-5];
ee2[-4] = (k00) * A4 - (k11) * A5;
ee2[-5] = (k11) * A4 + (k00) * A5;
k00 = ee0[-6] - ee2[-6];
k11 = ee0[-7] - ee2[-7];
ee0[-6] = ee0[-6] + ee2[-6];
ee0[-7] = ee0[-7] + ee2[-7];
ee2[-6] = (k00) * A6 - (k11) * A7;
ee2[-7] = (k11) * A6 + (k00) * A7;
ee0 -= k0;
ee2 -= k0;
}
}
static INLINE void iter_54(float *z)
{
float k00,k11,k22,k33;
float y0,y1,y2,y3;
k00 = z[ 0] - z[-4];
y0 = z[ 0] + z[-4];
y2 = z[-2] + z[-6];
k22 = z[-2] - z[-6];
z[-0] = y0 + y2; /* z0 + z4 + z2 + z6 */
z[-2] = y0 - y2; /* z0 + z4 - z2 - z6 */
/* done with y0,y2 */
k33 = z[-3] - z[-7];
z[-4] = k00 + k33; /* z0 - z4 + z3 - z7 */
z[-6] = k00 - k33; /* z0 - z4 - z3 + z7 */
/* done with k33 */
k11 = z[-1] - z[-5];
y1 = z[-1] + z[-5];
y3 = z[-3] + z[-7];
z[-1] = y1 + y3; /* z1 + z5 + z3 + z7 */
z[-3] = y1 - y3; /* z1 + z5 - z3 - z7 */
z[-5] = k11 - k22; /* z1 - z5 + z2 - z6 */
z[-7] = k11 + k22; /* z1 - z5 - z2 + z6 */
}
static void imdct_step3_inner_s_loop_ld654(int n, float *e, int i_off, float *A, int base_n)
{
int a_off = base_n >> 3;
float A2 = A[0+a_off];
float *z = e + i_off;
float *base = z - 16 * n;
while (z > base) {
float k00,k11;
k00 = z[-0] - z[-8];
k11 = z[-1] - z[-9];
z[-0] = z[-0] + z[-8];
z[-1] = z[-1] + z[-9];
z[-8] = k00;
z[-9] = k11 ;
k00 = z[ -2] - z[-10];
k11 = z[ -3] - z[-11];
z[ -2] = z[ -2] + z[-10];
z[ -3] = z[ -3] + z[-11];
z[-10] = (k00+k11) * A2;
z[-11] = (k11-k00) * A2;
k00 = z[-12] - z[ -4]; /* reverse to avoid a unary negation */
k11 = z[ -5] - z[-13];
z[ -4] = z[ -4] + z[-12];
z[ -5] = z[ -5] + z[-13];
z[-12] = k11;
z[-13] = k00;
k00 = z[-14] - z[ -6]; /* reverse to avoid a unary negation */
k11 = z[ -7] - z[-15];
z[ -6] = z[ -6] + z[-14];
z[ -7] = z[ -7] + z[-15];
z[-14] = (k00+k11) * A2;
z[-15] = (k00-k11) * A2;
iter_54(z);
iter_54(z-8);
z -= 16;
}
}
static void inverse_mdct(float *buffer, int n, vorb *f, int blocktype)
{
int n2 = n >> 1, n4 = n >> 2, n8 = n >> 3, l;
int ld;
/* @OPTIMIZE: reduce register pressure by using fewer variables? */
int save_point = temp_alloc_save(f);
float *buf2 = (float *) temp_alloc(f, n2 * sizeof(*buf2));
float *u=NULL,*v=NULL;
/* twiddle factors */
float *A = f->A[blocktype];
/* IMDCT algorithm from "The use of multirate filter banks for coding of high quality digital audio"
* See notes about bugs in that paper in less-optimal implementation 'inverse_mdct_old' after this function.
* kernel from paper
* merged:
* copy and reflect spectral data
* step 0
* note that it turns out that the items added together during
* this step are, in fact, being added to themselves (as reflected
* by step 0). inexplicable inefficiency! this became obvious
* once I combined the passes.
* so there's a missing 'times 2' here (for adding X to itself).
* this propogates through linearly to the end, where the numbers
* are 1/2 too small, and need to be compensated for.
*/
{
float *d,*e, *AA, *e_stop;
d = &buf2[n2-2];
AA = A;
e = &buffer[0];
e_stop = &buffer[n2];
while (e != e_stop) {
d[1] = (e[0] * AA[0] - e[2]*AA[1]);
d[0] = (e[0] * AA[1] + e[2]*AA[0]);
d -= 2;
AA += 2;
e += 4;
}
e = &buffer[n2-3];
while (d >= buf2) {
d[1] = (-e[2] * AA[0] - -e[0]*AA[1]);
d[0] = (-e[2] * AA[1] + -e[0]*AA[0]);
d -= 2;
AA += 2;
e -= 4;
}
}
/* now we use symbolic names for these, so that we can
* possibly swap their meaning as we change which operations
* are in place */
u = buffer;
v = buf2;
/* step 2 (paper output is w, now u)
* this could be in place, but the data ends up in the wrong
* place... _somebody_'s got to swap it, so this is nominated */
{
float *AA = &A[n2-8];
float *d0,*d1, *e0, *e1;
e0 = &v[n4];
e1 = &v[0];
d0 = &u[n4];
d1 = &u[0];
while (AA >= A) {
float v40_20, v41_21;
v41_21 = e0[1] - e1[1];
v40_20 = e0[0] - e1[0];
d0[1] = e0[1] + e1[1];
d0[0] = e0[0] + e1[0];
d1[1] = v41_21*AA[4] - v40_20*AA[5];
d1[0] = v40_20*AA[4] + v41_21*AA[5];
v41_21 = e0[3] - e1[3];
v40_20 = e0[2] - e1[2];
d0[3] = e0[3] + e1[3];
d0[2] = e0[2] + e1[2];
d1[3] = v41_21*AA[0] - v40_20*AA[1];
d1[2] = v40_20*AA[0] + v41_21*AA[1];
AA -= 8;
d0 += 4;
d1 += 4;
e0 += 4;
e1 += 4;
}
}
/* step 3 */
ld = ilog(n) - 1; /* ilog is off-by-one from normal definitions */
/* optimized step 3:
* the original step3 loop can be nested r inside s or s inside r;
* it's written originally as s inside r, but this is dumb when r
* iterates many times, and s few. So I have two copies of it and
* switch between them halfway.
* this is iteration 0 of step 3 */
imdct_step3_iter0_loop(n >> 4, u, n2-1-n4*0, -(n >> 3), A);
imdct_step3_iter0_loop(n >> 4, u, n2-1-n4*1, -(n >> 3), A);
/* this is iteration 1 of step 3 */
imdct_step3_inner_r_loop(n >> 5, u, n2-1 - n8*0, -(n >> 4), A, 16);
imdct_step3_inner_r_loop(n >> 5, u, n2-1 - n8*1, -(n >> 4), A, 16);
imdct_step3_inner_r_loop(n >> 5, u, n2-1 - n8*2, -(n >> 4), A, 16);
imdct_step3_inner_r_loop(n >> 5, u, n2-1 - n8*3, -(n >> 4), A, 16);
l=2;
for (; l < (ld-3)>>1; ++l) {
int k0 = n >> (l+2), k0_2 = k0>>1;
int lim = 1 << (l+1);
int i;
for (i=0; i < lim; ++i)
imdct_step3_inner_r_loop(n >> (l+4), u, n2-1 - k0*i, -k0_2, A, 1 << (l+3));
}
for (; l < ld-6; ++l) {
int k0 = n >> (l+2), k1 = 1 << (l+3), k0_2 = k0>>1;
int rlim = n >> (l+6), r;
int lim = 1 << (l+1);
int i_off;
float *A0 = A;
i_off = n2-1;
for (r=rlim; r > 0; --r) {
imdct_step3_inner_s_loop(lim, u, i_off, -k0_2, A0, k1, k0);
A0 += k1*4;
i_off -= 8;
}
}
/* iterations with count:
* ld-6,-5,-4 all interleaved together
* the big win comes from getting rid of needless flops
* due to the constants on pass 5 & 4 being all 1 and 0;
* combining them to be simultaneous to improve cache made little difference
*/
imdct_step3_inner_s_loop_ld654(n >> 5, u, n2-1, A, n);
/* output is u
* step 4, 5, and 6
* cannot be in-place because of step 5 */
{
uint16_t *bitrev = f->bit_reverse[blocktype];
/* weirdly, I'd have thought reading sequentially and writing
* erratically would have been better than vice-versa, but in
* fact that's not what my testing showed. (That is, with
* j = bitreverse(i), do you read i and write j, or read j and write i.) */
float *d0 = &v[n4-4];
float *d1 = &v[n2-4];
while (d0 >= v) {
int k4;
k4 = bitrev[0];
d1[3] = u[k4+0];
d1[2] = u[k4+1];
d0[3] = u[k4+2];
d0[2] = u[k4+3];
k4 = bitrev[1];
d1[1] = u[k4+0];
d1[0] = u[k4+1];
d0[1] = u[k4+2];
d0[0] = u[k4+3];
d0 -= 4;
d1 -= 4;
bitrev += 2;
}
}
/* (paper output is u, now v) */
/* data must be in buf2 */
assert(v == buf2);
/* step 7 (paper output is v, now v)
* this is now in place */
{
float *C = f->C[blocktype];
float *d, *e;
d = v;
e = v + n2 - 4;
while (d < e) {
float a02,a11,b0,b1,b2,b3;
a02 = d[0] - e[2];
a11 = d[1] + e[3];
b0 = C[1]*a02 + C[0]*a11;
b1 = C[1]*a11 - C[0]*a02;
b2 = d[0] + e[ 2];
b3 = d[1] - e[ 3];
d[0] = b2 + b0;
d[1] = b3 + b1;
e[2] = b2 - b0;
e[3] = b1 - b3;
a02 = d[2] - e[0];
a11 = d[3] + e[1];
b0 = C[3]*a02 + C[2]*a11;
b1 = C[3]*a11 - C[2]*a02;
b2 = d[2] + e[ 0];
b3 = d[3] - e[ 1];
d[2] = b2 + b0;
d[3] = b3 + b1;
e[0] = b2 - b0;
e[1] = b1 - b3;
C += 4;
d += 4;
e -= 4;
}
}
/* data must be in buf2
* step 8+decode (paper output is X, now buffer)
* this generates pairs of data a la 8 and pushes them directly through
* the decode kernel (pushing rather than pulling) to avoid having
* to make another pass later
* this cannot POSSIBLY be in place, so we refer to the buffers directly
*/
{
float *d0,*d1,*d2,*d3;
float *B = f->B[blocktype] + n2 - 8;
float *e = buf2 + n2 - 8;
d0 = &buffer[0];
d1 = &buffer[n2-4];
d2 = &buffer[n2];
d3 = &buffer[n-4];
while (e >= v) {
float p0,p1,p2,p3;
p3 = e[6]*B[7] - e[7]*B[6];
p2 = -e[6]*B[6] - e[7]*B[7];
d0[0] = p3;
d1[3] = - p3;
d2[0] = p2;
d3[3] = p2;
p1 = e[4]*B[5] - e[5]*B[4];
p0 = -e[4]*B[4] - e[5]*B[5];
d0[1] = p1;
d1[2] = - p1;
d2[1] = p0;
d3[2] = p0;
p3 = e[2]*B[3] - e[3]*B[2];
p2 = -e[2]*B[2] - e[3]*B[3];
d0[2] = p3;
d1[1] = - p3;
d2[2] = p2;
d3[1] = p2;
p1 = e[0]*B[1] - e[1]*B[0];
p0 = -e[0]*B[0] - e[1]*B[1];
d0[3] = p1;
d1[0] = - p1;
d2[3] = p0;
d3[0] = p0;
B -= 8;
e -= 8;
d0 += 4;
d2 += 4;
d1 -= 4;
d3 -= 4;
}
}
temp_alloc_restore(f,save_point);
}
static float *get_window(vorb *f, int len)
{
len <<= 1;
if (len == f->blocksize_0) return f->window[0];
if (len == f->blocksize_1) return f->window[1];
assert(0);
return NULL;
}
typedef int16_t YTYPE;
static int do_floor(vorb *f, Mapping *map, int i, int n, float *target, YTYPE *finalY, uint8_t *step2_flag)
{
int n2 = n >> 1;
int s = map->chan[i].mux, floor;
floor = map->submap_floor[s];
if (f->floor_types[floor] == 0) {
return error(f, VORBIS_invalid_stream);
} else {
Floor1 *g = &f->floor_config[floor].floor1;
int j,q;
int lx = 0, ly = finalY[0] * g->floor1_multiplier;
for (q=1; q < g->values; ++q) {
j = g->sorted_order[q];
if (finalY[j] >= 0)
{
int hy = finalY[j] * g->floor1_multiplier;
int hx = g->Xlist[j];
draw_line(target, lx,ly, hx,hy, n2);
lx = hx;
ly = hy;
}
}
if (lx < n2)
/* optimization of: draw_line(target, lx,ly, n,ly, n2); */
for (j=lx; j < n2; ++j)
LINE_OP(target[j], inverse_db_table[ly]);
}
return TRUE;
}
static int vorbis_decode_initial(vorb *f, int *p_left_start, int *p_left_end, int *p_right_start, int *p_right_end, int *mode)
{
Mode *m;
int i, n, prev, next, window_center;
f->channel_buffer_start = f->channel_buffer_end = 0;
retry:
if (f->eof) return FALSE;
if (!maybe_start_packet(f))
return FALSE;
/* check packet type */
if (get_bits(f,1) != 0) {
if (IS_PUSH_MODE(f))
return error(f,VORBIS_bad_packet_type);
while (EOP != get8_packet(f));
goto retry;
}
if (f->alloc.alloc_buffer)
assert(f->alloc.alloc_buffer_length_in_bytes == f->temp_offset);
i = get_bits(f, ilog(f->mode_count-1));
if (i == EOP) return FALSE;
if (i >= f->mode_count) return FALSE;
*mode = i;
m = f->mode_config + i;
if (m->blockflag) {
n = f->blocksize_1;
prev = get_bits(f,1);
next = get_bits(f,1);
} else {
prev = next = 0;
n = f->blocksize_0;
}
/* WINDOWING */
window_center = n >> 1;
if (m->blockflag && !prev) {
*p_left_start = (n - f->blocksize_0) >> 2;
*p_left_end = (n + f->blocksize_0) >> 2;
} else {
*p_left_start = 0;
*p_left_end = window_center;
}
if (m->blockflag && !next) {
*p_right_start = (n*3 - f->blocksize_0) >> 2;
*p_right_end = (n*3 + f->blocksize_0) >> 2;
} else {
*p_right_start = window_center;
*p_right_end = n;
}
return TRUE;
}
static int vorbis_decode_packet_rest(vorb *f, int *len, Mode *m, int left_start, int left_end, int right_start, int right_end, int *p_left)
{
Mapping *map;
int i,j,k,n,n2;
int zero_channel[256];
int really_zero_channel[256];
/* WINDOWING */
n = f->blocksize[m->blockflag];
map = &f->mapping[m->mapping];
/* FLOORS */
n2 = n >> 1;
for (i=0; i < f->channels; ++i) {
int s = map->chan[i].mux, floor;
zero_channel[i] = FALSE;
floor = map->submap_floor[s];
if (f->floor_types[floor] == 0) {
return error(f, VORBIS_invalid_stream);
} else {
Floor1 *g = &f->floor_config[floor].floor1;
if (get_bits(f, 1)) {
short *finalY;
uint8_t step2_flag[256];
static int range_list[4] = { 256, 128, 86, 64 };
int range = range_list[g->floor1_multiplier-1];
int offset = 2;
finalY = f->finalY[i];
finalY[0] = get_bits(f, ilog(range)-1);
finalY[1] = get_bits(f, ilog(range)-1);
for (j=0; j < g->partitions; ++j) {
int pclass = g->partition_class_list[j];
int cdim = g->class_dimensions[pclass];
int cbits = g->class_subclasses[pclass];
int csub = (1 << cbits)-1;
int cval = 0;
if (cbits) {
Codebook *c = f->codebooks + g->class_masterbooks[pclass];
DECODE(cval,f,c);
}
for (k=0; k < cdim; ++k) {
int book = g->subclass_books[pclass][cval & csub];
cval = cval >> cbits;
if (book >= 0) {
int temp;
Codebook *c = f->codebooks + book;
DECODE(temp,f,c);
finalY[offset++] = temp;
} else
finalY[offset++] = 0;
}
}
if (f->valid_bits == INVALID_BITS) goto error; /* behavior according to spec */
step2_flag[0] = step2_flag[1] = 1;
for (j=2; j < g->values; ++j) {
int low, high, pred, highroom, lowroom, room, val;
low = g->neighbors[j][0];
high = g->neighbors[j][1];
#if 0
neighbors(g->Xlist, j, &low, &high);
#endif
pred = predict_point(g->Xlist[j], g->Xlist[low], g->Xlist[high], finalY[low], finalY[high]);
val = finalY[j];
highroom = range - pred;
lowroom = pred;
if (highroom < lowroom)
room = highroom * 2;
else
room = lowroom * 2;
if (val) {
step2_flag[low] = step2_flag[high] = 1;
step2_flag[j] = 1;
if (val >= room)
if (highroom > lowroom)
finalY[j] = val - lowroom + pred;
else
finalY[j] = pred - val + highroom - 1;
else
if (val & 1)
finalY[j] = pred - ((val+1)>>1);
else
finalY[j] = pred + (val>>1);
} else {
step2_flag[j] = 0;
finalY[j] = pred;
}
}
/* defer final floor computation until _after_ residue */
for (j=0; j < g->values; ++j) {
if (!step2_flag[j])
finalY[j] = -1;
}
} else {
error:
zero_channel[i] = TRUE;
}
/* So we just defer everything else to later */
/* at this point we've decoded the floor into buffer */
}
}
/* at this point we've decoded all floors */
if (f->alloc.alloc_buffer)
assert(f->alloc.alloc_buffer_length_in_bytes == f->temp_offset);
/* re-enable coupled channels if necessary */
memcpy(really_zero_channel, zero_channel, sizeof(really_zero_channel[0]) * f->channels);
for (i=0; i < map->coupling_steps; ++i)
if (!zero_channel[map->chan[i].magnitude] || !zero_channel[map->chan[i].angle]) {
zero_channel[map->chan[i].magnitude] = zero_channel[map->chan[i].angle] = FALSE;
}
/* RESIDUE DECODE */
for (i=0; i < map->submaps; ++i) {
float *residue_buffers[STB_VORBIS_MAX_CHANNELS];
int r;
uint8_t do_not_decode[256] = {0};
int ch = 0;
for (j=0; j < f->channels; ++j) {
if (map->chan[j].mux == i) {
if (zero_channel[j]) {
do_not_decode[ch] = TRUE;
residue_buffers[ch] = NULL;
} else {
do_not_decode[ch] = FALSE;
residue_buffers[ch] = f->channel_buffers[j];
}
++ch;
}
}
r = map->submap_residue[i];
decode_residue(f, residue_buffers, ch, n2, r, do_not_decode);
}
if (f->alloc.alloc_buffer)
assert(f->alloc.alloc_buffer_length_in_bytes == f->temp_offset);
/* INVERSE COUPLING */
for (i = map->coupling_steps-1; i >= 0; --i) {
int n2 = n >> 1;
float *m = f->channel_buffers[map->chan[i].magnitude];
float *a = f->channel_buffers[map->chan[i].angle ];
for (j=0; j < n2; ++j) {
float a2,m2;
if (m[j] > 0)
if (a[j] > 0)
{
m2 = m[j];
a2 = m[j] - a[j];
}
else
{
a2 = m[j];
m2 = m[j] + a[j];
}
else
if (a[j] > 0)
{
m2 = m[j];
a2 = m[j] + a[j];
}
else
{
a2 = m[j];
m2 = m[j] - a[j];
}
m[j] = m2;
a[j] = a2;
}
}
/* finish decoding the floors */
for (i=0; i < f->channels; ++i) {
if (really_zero_channel[i]) {
memset(f->channel_buffers[i], 0, sizeof(*f->channel_buffers[i]) * n2);
} else {
do_floor(f, map, i, n, f->channel_buffers[i], f->finalY[i], NULL);
}
}
/* INVERSE MDCT */
for (i=0; i < f->channels; ++i)
inverse_mdct(f->channel_buffers[i], n, f, m->blockflag);
/* this shouldn't be necessary, unless we exited on an error
* and want to flush to get to the next packet */
flush_packet(f);
if (f->first_decode) {
/* assume we start so first non-discarded sample is sample 0
* this isn't to spec, but spec would require us to read ahead
* and decode the size of all current frames--could be done,
* but presumably it's not a commonly used feature */
f->current_loc = -n2; /* start of first frame is positioned for discard */
/* we might have to discard samples "from" the next frame too,
* if we're lapping a large block then a small at the start? */
f->discard_samples_deferred = n - right_end;
f->current_loc_valid = TRUE;
f->first_decode = FALSE;
} else if (f->discard_samples_deferred) {
left_start += f->discard_samples_deferred;
*p_left = left_start;
f->discard_samples_deferred = 0;
} else if (f->previous_length == 0 && f->current_loc_valid) {
/* we're recovering from a seek... that means we're going to discard
* the samples from this packet even though we know our position from
* the last page header, so we need to update the position based on
* the discarded samples here
* but wait, the code below is going to add this in itself even
* on a discard, so we don't need to do it here... */
}
/* check if we have ogg information about the sample # for this packet */
if (f->last_seg_which == f->end_seg_with_known_loc) {
/* if we have a valid current loc, and this is final: */
if (f->current_loc_valid && (f->page_flag & PAGEFLAG_last_page)) {
uint32_t current_end = f->known_loc_for_packet - (n-right_end);
/* then let's infer the size of the (probably) short final frame */
if (current_end < f->current_loc + right_end) {
if (current_end < f->current_loc) {
/* negative truncation, that's impossible! */
*len = 0;
} else {
*len = current_end - f->current_loc;
}
*len += left_start;
f->current_loc += *len;
return TRUE;
}
}
/* otherwise, just set our sample loc
* guess that the ogg granule pos refers to the _middle_ of the
* last frame?
* set f->current_loc to the position of left_start */
f->current_loc = f->known_loc_for_packet - (n2-left_start);
f->current_loc_valid = TRUE;
}
if (f->current_loc_valid)
f->current_loc += (right_start - left_start);
if (f->alloc.alloc_buffer)
assert(f->alloc.alloc_buffer_length_in_bytes == f->temp_offset);
*len = right_end; /* ignore samples after the window goes to 0 */
return TRUE;
}
static int vorbis_decode_packet(vorb *f, int *len, int *p_left, int *p_right)
{
int mode, left_end, right_end;
if (!vorbis_decode_initial(f, p_left, &left_end, p_right, &right_end, &mode)) return 0;
return vorbis_decode_packet_rest(f, len, f->mode_config + mode, *p_left, left_end, *p_right, right_end, p_left);
}
static int vorbis_finish_frame(stb_vorbis *f, int len, int left, int right)
{
int prev,i,j;
/* we use right&left (the start of the right- and left-window sin()-regions)
* to determine how much to return, rather than inferring from the rules
* (same result, clearer code); 'left' indicates where our sin() window
* starts, therefore where the previous window's right edge starts, and
* therefore where to start mixing from the previous buffer. 'right'
* indicates where our sin() ending-window starts, therefore that's where
* we start saving, and where our returned-data ends.
* mixin from previous window */
if (f->previous_length) {
int i,j, n = f->previous_length;
float *w = get_window(f, n);
for (i=0; i < f->channels; ++i) {
for (j=0; j < n; ++j)
f->channel_buffers[i][left+j] =
f->channel_buffers[i][left+j]*w[ j] +
f->previous_window[i][ j]*w[n-1-j];
}
}
prev = f->previous_length;
/* last half of this data becomes previous window */
f->previous_length = len - right;
/* @OPTIMIZE: could avoid this copy by double-buffering the
* output (flipping previous_window with channel_buffers), but
* then previous_window would have to be 2x as large, and
* channel_buffers couldn't be temp mem (although they're NOT
* currently temp mem, they could be (unless we want to level
* performance by spreading out the computation)) */
for (i=0; i < f->channels; ++i)
for (j=0; right+j < len; ++j)
f->previous_window[i][j] = f->channel_buffers[i][right+j];
if (!prev)
/* there was no previous packet, so this data isn't valid...
* this isn't entirely true, only the would-have-overlapped data
* isn't valid, but this seems to be what the spec requires */
return 0;
/* truncate a short frame */
if (len < right) right = len;
f->samples_output += right-left;
return right - left;
}
static void vorbis_pump_first_frame(stb_vorbis *f)
{
int len, right, left;
if (vorbis_decode_packet(f, &len, &left, &right))
vorbis_finish_frame(f, len, left, right);
}
static int start_decoder(vorb *f)
{
uint8_t header[6], x,y;
int len,i,j,k, max_submaps = 0;
int longest_floorlist=0;
/* first page, first packet */
if (!start_page(f)) return FALSE;
/* validate page flag */
if (!(f->page_flag & PAGEFLAG_first_page)) return error(f, VORBIS_invalid_first_page);
if (f->page_flag & PAGEFLAG_last_page) return error(f, VORBIS_invalid_first_page);
if (f->page_flag & PAGEFLAG_continued_packet) return error(f, VORBIS_invalid_first_page);
/* check for expected packet length */
if (f->segment_count != 1) return error(f, VORBIS_invalid_first_page);
if (f->segments[0] != 30) return error(f, VORBIS_invalid_first_page);
/* read packet
* check packet header */
if (get8(f) != VORBIS_packet_id) return error(f, VORBIS_invalid_first_page);
if (!getn(f, header, 6)) return error(f, VORBIS_unexpected_eof);
if (!vorbis_validate(header)) return error(f, VORBIS_invalid_first_page);
/* vorbis_version */
if (get32(f) != 0) return error(f, VORBIS_invalid_first_page);
f->channels = get8(f); if (!f->channels) return error(f, VORBIS_invalid_first_page);
if (f->channels > STB_VORBIS_MAX_CHANNELS) return error(f, VORBIS_too_many_channels);
f->sample_rate = get32(f); if (!f->sample_rate) return error(f, VORBIS_invalid_first_page);
get32(f); /* bitrate_maximum */
get32(f); /* bitrate_nominal */
get32(f); /* bitrate_minimum */
x = get8(f);
{ int log0,log1;
log0 = x & 15;
log1 = x >> 4;
f->blocksize_0 = 1 << log0;
f->blocksize_1 = 1 << log1;
if (log0 < 6 || log0 > 13) return error(f, VORBIS_invalid_setup);
if (log1 < 6 || log1 > 13) return error(f, VORBIS_invalid_setup);
if (log0 > log1) return error(f, VORBIS_invalid_setup);
}
/* framing_flag */
x = get8(f);
if (!(x & 1)) return error(f, VORBIS_invalid_first_page);
/* second packet! */
if (!start_page(f)) return FALSE;
if (!start_packet(f)) return FALSE;
do {
len = next_segment(f);
skip(f, len);
f->bytes_in_seg = 0;
} while (len);
/* third packet! */
if (!start_packet(f)) return FALSE;
crc32_init(); /* always init it, to avoid multithread race conditions */
if (get8_packet(f) != VORBIS_packet_setup) return error(f, VORBIS_invalid_setup);
for (i=0; i < 6; ++i) header[i] = get8_packet(f);
if (!vorbis_validate(header)) return error(f, VORBIS_invalid_setup);
/* codebooks */
f->codebook_count = get_bits(f,8) + 1;
f->codebooks = (Codebook *) setup_malloc(f, sizeof(*f->codebooks) * f->codebook_count);
if (f->codebooks == NULL) return error(f, VORBIS_outofmem);
memset(f->codebooks, 0, sizeof(*f->codebooks) * f->codebook_count);
for (i=0; i < f->codebook_count; ++i) {
uint32_t *values;
int ordered, sorted_count;
int total=0;
uint8_t *lengths;
Codebook *c = f->codebooks+i;
x = get_bits(f, 8); if (x != 0x42) return error(f, VORBIS_invalid_setup);
x = get_bits(f, 8); if (x != 0x43) return error(f, VORBIS_invalid_setup);
x = get_bits(f, 8); if (x != 0x56) return error(f, VORBIS_invalid_setup);
x = get_bits(f, 8);
c->dimensions = (get_bits(f, 8)<<8) + x;
x = get_bits(f, 8);
y = get_bits(f, 8);
c->entries = (get_bits(f, 8)<<16) + (y<<8) + x;
ordered = get_bits(f,1);
c->sparse = ordered ? 0 : get_bits(f,1);
if (c->sparse)
lengths = (uint8_t *) setup_temp_malloc(f, c->entries);
else
lengths = c->codeword_lengths = (uint8_t *) setup_malloc(f, c->entries);
if (!lengths) return error(f, VORBIS_outofmem);
if (ordered) {
int current_entry = 0;
int current_length = get_bits(f,5) + 1;
while (current_entry < c->entries) {
int limit = c->entries - current_entry;
int n = get_bits(f, ilog(limit));
if (current_entry + n > (int) c->entries) { return error(f, VORBIS_invalid_setup); }
memset(lengths + current_entry, current_length, n);
current_entry += n;
++current_length;
}
} else {
for (j=0; j < c->entries; ++j) {
int present = c->sparse ? get_bits(f,1) : 1;
if (present) {
lengths[j] = get_bits(f, 5) + 1;
++total;
} else {
lengths[j] = NO_CODE;
}
}
}
if (c->sparse && total >= c->entries >> 2) {
/* convert sparse items to non-sparse! */
if (c->entries > (int) f->setup_temp_memory_required)
f->setup_temp_memory_required = c->entries;
c->codeword_lengths = (uint8_t *) setup_malloc(f, c->entries);
memcpy(c->codeword_lengths, lengths, c->entries);
setup_temp_free(f, lengths, c->entries); /* note this is only safe if there have been no intervening temp mallocs! */
lengths = c->codeword_lengths;
c->sparse = 0;
}
/* compute the size of the sorted tables */
if (c->sparse) {
sorted_count = total;
} else {
sorted_count = 0;
#ifndef STB_VORBIS_NO_HUFFMAN_BINARY_SEARCH
for (j=0; j < c->entries; ++j)
if (lengths[j] > STB_VORBIS_FAST_HUFFMAN_LENGTH && lengths[j] != NO_CODE)
++sorted_count;
#endif
}
c->sorted_entries = sorted_count;
values = NULL;
if (!c->sparse) {
c->codewords = (uint32_t *) setup_malloc(f, sizeof(c->codewords[0]) * c->entries);
if (!c->codewords) return error(f, VORBIS_outofmem);
} else {
unsigned int size;
if (c->sorted_entries) {
c->codeword_lengths = (uint8_t *) setup_malloc(f, c->sorted_entries);
if (!c->codeword_lengths) return error(f, VORBIS_outofmem);
c->codewords = (uint32_t *) setup_temp_malloc(f, sizeof(*c->codewords) * c->sorted_entries);
if (!c->codewords) return error(f, VORBIS_outofmem);
values = (uint32_t *) setup_temp_malloc(f, sizeof(*values) * c->sorted_entries);
if (!values) return error(f, VORBIS_outofmem);
}
size = c->entries + (sizeof(*c->codewords) + sizeof(*values)) * c->sorted_entries;
if (size > f->setup_temp_memory_required)
f->setup_temp_memory_required = size;
}
if (!compute_codewords(c, lengths, c->entries, values)) {
if (c->sparse) setup_temp_free(f, values, 0);
return error(f, VORBIS_invalid_setup);
}
if (c->sorted_entries) {
/* allocate an extra slot for sentinels */
c->sorted_codewords = (uint32_t *) setup_malloc(f, sizeof(*c->sorted_codewords) * (c->sorted_entries+1));
/* allocate an extra slot at the front so that c->sorted_values[-1] is defined
* so that we can catch that case without an extra if */
c->sorted_values = ( int *) setup_malloc(f, sizeof(*c->sorted_values ) * (c->sorted_entries+1));
if (c->sorted_values) { ++c->sorted_values; c->sorted_values[-1] = -1; }
compute_sorted_huffman(c, lengths, values);
}
if (c->sparse) {
setup_temp_free(f, values, sizeof(*values)*c->sorted_entries);
setup_temp_free(f, c->codewords, sizeof(*c->codewords)*c->sorted_entries);
setup_temp_free(f, lengths, c->entries);
c->codewords = NULL;
}
compute_accelerated_huffman(c);
c->lookup_type = get_bits(f, 4);
if (c->lookup_type > 2) return error(f, VORBIS_invalid_setup);
if (c->lookup_type > 0) {
uint16_t *mults;
c->minimum_value = float32_unpack(get_bits(f, 32));
c->delta_value = float32_unpack(get_bits(f, 32));
c->value_bits = get_bits(f, 4)+1;
c->sequence_p = get_bits(f,1);
if (c->lookup_type == 1) {
c->lookup_values = lookup1_values(c->entries, c->dimensions);
} else {
c->lookup_values = c->entries * c->dimensions;
}
mults = (uint16_t *) setup_temp_malloc(f, sizeof(mults[0]) * c->lookup_values);
if (mults == NULL) return error(f, VORBIS_outofmem);
for (j=0; j < (int) c->lookup_values; ++j) {
int q = get_bits(f, c->value_bits);
if (q == EOP) { setup_temp_free(f,mults,sizeof(mults[0])*c->lookup_values); return error(f, VORBIS_invalid_setup); }
mults[j] = q;
}
if (c->lookup_type == 1) {
int len, sparse = c->sparse;
/* pre-expand the lookup1-style multiplicands, to avoid a divide in the inner loop */
if (sparse) {
if (c->sorted_entries == 0) goto skip;
c->multiplicands = (stb_vorbis_codetype *) setup_malloc(f, sizeof(c->multiplicands[0]) * c->sorted_entries * c->dimensions);
} else
c->multiplicands = (stb_vorbis_codetype *) setup_malloc(f, sizeof(c->multiplicands[0]) * c->entries * c->dimensions);
if (c->multiplicands == NULL) { setup_temp_free(f,mults,sizeof(mults[0])*c->lookup_values); return error(f, VORBIS_outofmem); }
len = sparse ? c->sorted_entries : c->entries;
for (j=0; j < len; ++j) {
int z = sparse ? c->sorted_values[j] : j, div=1;
for (k=0; k < c->dimensions; ++k) {
int off = (z / div) % c->lookup_values;
c->multiplicands[j*c->dimensions + k] =
#ifndef STB_VORBIS_CODEBOOK_FLOATS
mults[off];
#else
mults[off]*c->delta_value + c->minimum_value;
/* in this case (and this case only) we could pre-expand c->sequence_p,
* and throw away the decode logic for it; have to ALSO do
* it in the case below, but it can only be done if
* STB_VORBIS_CODEBOOK_FLOATS */
#endif
div *= c->lookup_values;
}
}
setup_temp_free(f, mults,sizeof(mults[0])*c->lookup_values);
c->lookup_type = 2;
}
else
{
c->multiplicands = (stb_vorbis_codetype *) setup_malloc(f, sizeof(c->multiplicands[0]) * c->lookup_values);
#ifndef STB_VORBIS_CODEBOOK_FLOATS
memcpy(c->multiplicands, mults, sizeof(c->multiplicands[0]) * c->lookup_values);
#else
for (j=0; j < (int) c->lookup_values; ++j)
c->multiplicands[j] = mults[j] * c->delta_value + c->minimum_value;
#endif
setup_temp_free(f, mults,sizeof(mults[0])*c->lookup_values);
}
skip:;
#ifdef STB_VORBIS_CODEBOOK_FLOATS
if (c->lookup_type == 2 && c->sequence_p) {
for (j=1; j < (int) c->lookup_values; ++j)
c->multiplicands[j] = c->multiplicands[j-1];
c->sequence_p = 0;
}
#endif
}
}
/* time domain transfers (notused) */
x = get_bits(f, 6) + 1;
for (i=0; i < x; ++i) {
uint32_t z = get_bits(f, 16);
if (z != 0) return error(f, VORBIS_invalid_setup);
}
/* Floors */
f->floor_count = get_bits(f, 6)+1;
f->floor_config = (Floor *) setup_malloc(f, f->floor_count * sizeof(*f->floor_config));
for (i=0; i < f->floor_count; ++i) {
f->floor_types[i] = get_bits(f, 16);
if (f->floor_types[i] > 1) return error(f, VORBIS_invalid_setup);
if (f->floor_types[i] == 0) {
Floor0 *g = &f->floor_config[i].floor0;
g->order = get_bits(f,8);
g->rate = get_bits(f,16);
g->bark_map_size = get_bits(f,16);
g->amplitude_bits = get_bits(f,6);
g->amplitude_offset = get_bits(f,8);
g->number_of_books = get_bits(f,4) + 1;
for (j=0; j < g->number_of_books; ++j)
g->book_list[j] = get_bits(f,8);
return error(f, VORBIS_feature_not_supported);
} else {
STBV_Point p[31*8+2];
Floor1 *g = &f->floor_config[i].floor1;
int max_class = -1;
g->partitions = get_bits(f, 5);
for (j=0; j < g->partitions; ++j) {
g->partition_class_list[j] = get_bits(f, 4);
if (g->partition_class_list[j] > max_class)
max_class = g->partition_class_list[j];
}
for (j=0; j <= max_class; ++j) {
g->class_dimensions[j] = get_bits(f, 3)+1;
g->class_subclasses[j] = get_bits(f, 2);
if (g->class_subclasses[j]) {
g->class_masterbooks[j] = get_bits(f, 8);
if (g->class_masterbooks[j] >= f->codebook_count) return error(f, VORBIS_invalid_setup);
}
for (k=0; k < 1 << g->class_subclasses[j]; ++k) {
g->subclass_books[j][k] = get_bits(f,8)-1;
if (g->subclass_books[j][k] >= f->codebook_count) return error(f, VORBIS_invalid_setup);
}
}
g->floor1_multiplier = get_bits(f,2)+1;
g->rangebits = get_bits(f,4);
g->Xlist[0] = 0;
g->Xlist[1] = 1 << g->rangebits;
g->values = 2;
for (j=0; j < g->partitions; ++j) {
int c = g->partition_class_list[j];
for (k=0; k < g->class_dimensions[c]; ++k) {
g->Xlist[g->values] = get_bits(f, g->rangebits);
++g->values;
}
}
/* precompute the sorting */
for (j=0; j < g->values; ++j) {
p[j].x = g->Xlist[j];
p[j].y = j;
}
qsort(p, g->values, sizeof(p[0]), point_compare);
for (j=0; j < g->values; ++j)
g->sorted_order[j] = (uint8_t) p[j].y;
/* precompute the neighbors */
for (j=2; j < g->values; ++j)
{
int low = 0;
int hi = 0;
neighbors(g->Xlist, j, &low,&hi);
g->neighbors[j][0] = low;
g->neighbors[j][1] = hi;
}
if (g->values > longest_floorlist)
longest_floorlist = g->values;
}
}
/* Residue */
f->residue_count = get_bits(f, 6)+1;
f->residue_config = (Residue *) setup_malloc(f, f->residue_count * sizeof(*f->residue_config));
for (i=0; i < f->residue_count; ++i) {
uint8_t residue_cascade[64];
Residue *r = f->residue_config+i;
f->residue_types[i] = get_bits(f, 16);
if (f->residue_types[i] > 2) return error(f, VORBIS_invalid_setup);
r->begin = get_bits(f, 24);
r->end = get_bits(f, 24);
r->part_size = get_bits(f,24)+1;
r->classifications = get_bits(f,6)+1;
r->classbook = get_bits(f,8);
for (j=0; j < r->classifications; ++j) {
uint8_t high_bits=0;
uint8_t low_bits=get_bits(f,3);
if (get_bits(f,1))
high_bits = get_bits(f,5);
residue_cascade[j] = high_bits*8 + low_bits;
}
r->residue_books = (short (*)[8]) setup_malloc(f, sizeof(r->residue_books[0]) * r->classifications);
for (j=0; j < r->classifications; ++j) {
for (k=0; k < 8; ++k) {
if (residue_cascade[j] & (1 << k)) {
r->residue_books[j][k] = get_bits(f, 8);
if (r->residue_books[j][k] >= f->codebook_count) return error(f, VORBIS_invalid_setup);
} else {
r->residue_books[j][k] = -1;
}
}
}
/* precompute the classifications[] array to avoid inner-loop mod/divide
* call it 'classdata' since we already have r->classifications */
r->classdata = (uint8_t **) setup_malloc(f, sizeof(*r->classdata) * f->codebooks[r->classbook].entries);
if (!r->classdata) return error(f, VORBIS_outofmem);
memset(r->classdata, 0, sizeof(*r->classdata) * f->codebooks[r->classbook].entries);
for (j=0; j < f->codebooks[r->classbook].entries; ++j) {
int classwords = f->codebooks[r->classbook].dimensions;
int temp = j;
r->classdata[j] = (uint8_t *) setup_malloc(f, sizeof(r->classdata[j][0]) * classwords);
for (k=classwords-1; k >= 0; --k) {
r->classdata[j][k] = temp % r->classifications;
temp /= r->classifications;
}
}
}
f->mapping_count = get_bits(f,6)+1;
f->mapping = (Mapping *) setup_malloc(f, f->mapping_count * sizeof(*f->mapping));
for (i=0; i < f->mapping_count; ++i) {
Mapping *m = f->mapping + i;
int mapping_type = get_bits(f,16);
if (mapping_type != 0) return error(f, VORBIS_invalid_setup);
m->chan = (MappingChannel *) setup_malloc(f, f->channels * sizeof(*m->chan));
if (get_bits(f,1))
m->submaps = get_bits(f,4)+1;
else
m->submaps = 1;
if (m->submaps > max_submaps)
max_submaps = m->submaps;
if (get_bits(f,1)) {
m->coupling_steps = get_bits(f,8)+1;
for (k=0; k < m->coupling_steps; ++k) {
m->chan[k].magnitude = get_bits(f, ilog(f->channels-1));
m->chan[k].angle = get_bits(f, ilog(f->channels-1));
if (m->chan[k].magnitude >= f->channels) return error(f, VORBIS_invalid_setup);
if (m->chan[k].angle >= f->channels) return error(f, VORBIS_invalid_setup);
if (m->chan[k].magnitude == m->chan[k].angle) return error(f, VORBIS_invalid_setup);
}
} else
m->coupling_steps = 0;
/* reserved field */
if (get_bits(f,2)) return error(f, VORBIS_invalid_setup);
if (m->submaps > 1) {
for (j=0; j < f->channels; ++j) {
m->chan[j].mux = get_bits(f, 4);
if (m->chan[j].mux >= m->submaps) return error(f, VORBIS_invalid_setup);
}
} else
/* @SPECIFICATION: this case is missing from the spec */
for (j=0; j < f->channels; ++j)
m->chan[j].mux = 0;
for (j=0; j < m->submaps; ++j) {
get_bits(f,8); /* discard */
m->submap_floor[j] = get_bits(f,8);
m->submap_residue[j] = get_bits(f,8);
if (m->submap_floor[j] >= f->floor_count) return error(f, VORBIS_invalid_setup);
if (m->submap_residue[j] >= f->residue_count) return error(f, VORBIS_invalid_setup);
}
}
/* Modes */
f->mode_count = get_bits(f, 6)+1;
for (i=0; i < f->mode_count; ++i) {
Mode *m = f->mode_config+i;
m->blockflag = get_bits(f,1);
m->windowtype = get_bits(f,16);
m->transformtype = get_bits(f,16);
m->mapping = get_bits(f,8);
if (m->windowtype != 0) return error(f, VORBIS_invalid_setup);
if (m->transformtype != 0) return error(f, VORBIS_invalid_setup);
if (m->mapping >= f->mapping_count) return error(f, VORBIS_invalid_setup);
}
flush_packet(f);
f->previous_length = 0;
for (i=0; i < f->channels; ++i) {
f->channel_buffers[i] = (float *) setup_malloc(f, sizeof(float) * f->blocksize_1);
f->previous_window[i] = (float *) setup_malloc(f, sizeof(float) * f->blocksize_1/2);
f->finalY[i] = (int16_t *) setup_malloc(f, sizeof(int16_t) * longest_floorlist);
}
if (!init_blocksize(f, 0, f->blocksize_0)) return FALSE;
if (!init_blocksize(f, 1, f->blocksize_1)) return FALSE;
f->blocksize[0] = f->blocksize_0;
f->blocksize[1] = f->blocksize_1;
/* compute how much temporary memory is needed */
/* 1. */
{
uint32_t imdct_mem = (f->blocksize_1 * sizeof(float) >> 1);
uint32_t classify_mem;
int i,max_part_read=0;
for (i=0; i < f->residue_count; ++i) {
Residue *r = f->residue_config + i;
int n_read = r->end - r->begin;
int part_read = n_read / r->part_size;
if (part_read > max_part_read)
max_part_read = part_read;
}
classify_mem = f->channels * (sizeof(void*) + max_part_read * sizeof(uint8_t *));
f->temp_memory_required = classify_mem;
if (imdct_mem > f->temp_memory_required)
f->temp_memory_required = imdct_mem;
}
f->first_decode = TRUE;
if (f->alloc.alloc_buffer) {
assert(f->temp_offset == f->alloc.alloc_buffer_length_in_bytes);
/* check if there's enough temp memory so we don't error later */
if (f->setup_offset + sizeof(*f) + f->temp_memory_required > (unsigned) f->temp_offset)
return error(f, VORBIS_outofmem);
}
f->first_audio_page_offset = stb_vorbis_get_file_offset(f);
return TRUE;
}
static void vorbis_deinit(stb_vorbis *p)
{
int i,j;
for (i=0; i < p->residue_count; ++i) {
Residue *r = p->residue_config+i;
if (r->classdata) {
for (j=0; j < p->codebooks[r->classbook].entries; ++j)
setup_free(p, r->classdata[j]);
setup_free(p, r->classdata);
}
setup_free(p, r->residue_books);
}
if (p->codebooks) {
for (i=0; i < p->codebook_count; ++i) {
Codebook *c = p->codebooks + i;
setup_free(p, c->codeword_lengths);
setup_free(p, c->multiplicands);
setup_free(p, c->codewords);
setup_free(p, c->sorted_codewords);
/* c->sorted_values[-1] is the first entry in the array */
setup_free(p, c->sorted_values ? c->sorted_values-1 : NULL);
}
setup_free(p, p->codebooks);
}
setup_free(p, p->floor_config);
setup_free(p, p->residue_config);
for (i=0; i < p->mapping_count; ++i)
setup_free(p, p->mapping[i].chan);
setup_free(p, p->mapping);
for (i=0; i < p->channels; ++i) {
setup_free(p, p->channel_buffers[i]);
setup_free(p, p->previous_window[i]);
setup_free(p, p->finalY[i]);
}
for (i=0; i < 2; ++i) {
setup_free(p, p->A[i]);
setup_free(p, p->B[i]);
setup_free(p, p->C[i]);
setup_free(p, p->window[i]);
setup_free(p, p->bit_reverse[i]);
}
}
void stb_vorbis_close(stb_vorbis *p)
{
if (p == NULL) return;
vorbis_deinit(p);
setup_free(p,p);
}
static void vorbis_init(stb_vorbis *p, stb_vorbis_alloc *z)
{
memset(p, 0, sizeof(*p)); /* NULL out all malloc'd pointers to start */
if (z) {
p->alloc = *z;
p->alloc.alloc_buffer_length_in_bytes = (p->alloc.alloc_buffer_length_in_bytes+3) & ~3;
p->temp_offset = p->alloc.alloc_buffer_length_in_bytes;
}
p->eof = 0;
p->error = VORBIS__no_error;
p->stream = NULL;
p->codebooks = NULL;
p->page_crc_tests = -1;
}
int stb_vorbis_get_sample_offset(stb_vorbis *f)
{
if (f->current_loc_valid)
return f->current_loc;
return -1;
}
stb_vorbis_info stb_vorbis_get_info(stb_vorbis *f)
{
stb_vorbis_info d;
d.channels = f->channels;
d.sample_rate = f->sample_rate;
d.setup_memory_required = f->setup_memory_required;
d.setup_temp_memory_required = f->setup_temp_memory_required;
d.temp_memory_required = f->temp_memory_required;
d.max_frame_size = f->blocksize_1 >> 1;
return d;
}
int stb_vorbis_get_error(stb_vorbis *f)
{
int e = f->error;
f->error = VORBIS__no_error;
return e;
}
static stb_vorbis * vorbis_alloc(stb_vorbis *f)
{
stb_vorbis *p = (stb_vorbis *) setup_malloc(f, sizeof(*p));
return p;
}
unsigned int stb_vorbis_get_file_offset(stb_vorbis *f)
{
return (unsigned int)(f->stream - f->stream_start);
}
#ifndef STB_VORBIS_NO_PULLDATA_API
/* DATA-PULLING API */
static uint32_t vorbis_find_page(stb_vorbis *f, uint32_t *end, uint32_t *last)
{
for(;;) {
int n;
if (f->eof) return 0;
n = get8(f);
if (n == 0x4f) { /* page header */
unsigned int retry_loc = stb_vorbis_get_file_offset(f);
int i;
/* check if we're off the end of a file_section stream */
if (retry_loc - 25 > f->stream_len)
return 0;
/* check the rest of the header */
for (i=1; i < 4; ++i)
if (get8(f) != ogg_page_header[i])
break;
if (f->eof) return 0;
if (i == 4) {
uint8_t header[27];
uint32_t i, crc, goal, len;
for (i=0; i < 4; ++i)
header[i] = ogg_page_header[i];
for (; i < 27; ++i)
header[i] = get8(f);
if (f->eof) return 0;
if (header[4] != 0) goto invalid;
goal = header[22] + (header[23] << 8) + (header[24]<<16) + (header[25]<<24);
for (i=22; i < 26; ++i)
header[i] = 0;
crc = 0;
for (i=0; i < 27; ++i)
crc = crc32_update(crc, header[i]);
len = 0;
for (i=0; i < header[26]; ++i) {
int s = get8(f);
crc = crc32_update(crc, s);
len += s;
}
if (len && f->eof) return 0;
for (i=0; i < len; ++i)
crc = crc32_update(crc, get8(f));
/* finished parsing probable page */
if (crc == goal) {
/* we could now check that it's either got the last
* page flag set, OR it's followed by the capture
* pattern, but I guess TECHNICALLY you could have
* a file with garbage between each ogg page and recover
* from it automatically? So even though that paranoia
* might decrease the chance of an invalid decode by
* another 2^32, not worth it since it would hose those
* invalid-but-useful files? */
if (end)
*end = stb_vorbis_get_file_offset(f);
if (last) {
if (header[5] & 0x04)
*last = 1;
else
*last = 0;
}
set_file_offset(f, retry_loc-1);
return 1;
}
}
invalid:
/* not a valid page, so rewind and look for next one */
set_file_offset(f, retry_loc);
}
}
}
/* seek is implemented with 'interpolation search'--this is like
* binary search, but we use the data values to estimate the likely
* location of the data item (plus a bit of a bias so when the
* estimation is wrong we don't waste overly much time)
*/
#define SAMPLE_unknown 0xffffffff
/* ogg vorbis, in its insane infinite wisdom, only provides
* information about the sample at the END of the page.
* therefore we COULD have the data we need in the current
* page, and not know it. we could just use the end location
* as our only knowledge for bounds, seek back, and eventually
* the binary search finds it. or we can try to be smart and
* not waste time trying to locate more pages. we try to be
* smart, since this data is already in memory anyway, so
* doing needless I/O would be crazy!
*/
static int vorbis_analyze_page(stb_vorbis *f, ProbedPage *z)
{
uint8_t lacing[255];
uint8_t packet_type[255];
int num_packet, packet_start;
int i,len;
uint32_t samples;
uint8_t header[27] = {0};
/* record where the page starts */
z->page_start = stb_vorbis_get_file_offset(f);
/* parse the header */
getn(f, header, 27);
assert(header[0] == 'O' && header[1] == 'g' && header[2] == 'g' && header[3] == 'S');
getn(f, lacing, header[26]);
/* determine the length of the payload */
len = 0;
for (i=0; i < header[26]; ++i)
len += lacing[i];
/* this implies where the page ends */
z->page_end = z->page_start + 27 + header[26] + len;
/* read the last-decoded sample out of the data */
z->last_decoded_sample = header[6] + (header[7] << 8) + (header[8] << 16) + (header[9] << 16);
if (header[5] & 4) {
/* if this is the last page, it's not possible to work
* backwards to figure out the first sample! whoops! fuck. */
z->first_decoded_sample = SAMPLE_unknown;
set_file_offset(f, z->page_start);
return 1;
}
/* scan through the frames to determine the sample-count of each one...
* our goal is the sample # of the first fully-decoded sample on the
* page, which is the first decoded sample of the 2nd packet */
num_packet=0;
packet_start = ((header[5] & 1) == 0);
for (i=0; i < header[26]; ++i) {
if (packet_start) {
uint8_t n,b;
if (lacing[i] == 0) goto bail; /* trying to read from zero-length packet */
n = get8(f);
/* if bottom bit is non-zero, we've got corruption */
if (n & 1) goto bail;
n >>= 1;
b = ilog(f->mode_count-1);
n &= (1 << b)-1;
if (n >= f->mode_count) goto bail;
packet_type[num_packet++] = f->mode_config[n].blockflag;
skip(f, lacing[i]-1);
} else
skip(f, lacing[i]);
packet_start = (lacing[i] < 255);
}
/* now that we know the sizes of all the pages, we can start determining
* how much sample data there is. */
samples = 0;
/* for the last packet, we step by its whole length, because the definition
* is that we encoded the end sample loc of the 'last packet completed',
* where 'completed' refers to packets being split, and we are left to guess
* what 'end sample loc' means. we assume it means ignoring the fact that
* the last half of the data is useless without windowing against the next
* packet... (so it's not REALLY complete in that sense)
*/
if (num_packet > 1)
samples += f->blocksize[packet_type[num_packet-1]];
for (i=num_packet-2; i >= 1; --i) {
/* now, for this packet, how many samples do we have that
* do not overlap the following packet? */
if (packet_type[i] == 1)
if (packet_type[i+1] == 1)
samples += f->blocksize_1 >> 1;
else
samples += ((f->blocksize_1 - f->blocksize_0) >> 2) + (f->blocksize_0 >> 1);
else
samples += f->blocksize_0 >> 1;
}
/* now, at this point, we've rewound to the very beginning of the
* _second_ packet. if we entirely discard the first packet after
* a seek, this will be exactly the right sample number. HOWEVER!
* we can't as easily compute this number for the LAST page. The
* only way to get the sample offset of the LAST page is to use
* the end loc from the previous page. But what that returns us
* is _exactly_ the place where we get our first non-overlapped
* sample. (I think. Stupid spec for being ambiguous.) So for
* consistency it's better to do that here, too. However, that
* will then require us to NOT discard all of the first frame we
* decode, in some cases, which means an even weirder frame size
* and extra code. what a fucking pain.
* we're going to discard the first packet if we
* start the seek here, so we don't care about it. (we could actually
* do better; if the first packet is long, and the previous packet
* is short, there's actually data in the first half of the first
* packet that doesn't need discarding... but not worth paying the
* effort of tracking that of that here and in the seeking logic)
* except crap, if we infer it from the _previous_ packet's end
* location, we DO need to use that definition... and we HAVE to
* infer the start loc of the LAST packet from the previous packet's
* end location. fuck you, ogg vorbis. */
z->first_decoded_sample = z->last_decoded_sample - samples;
/* restore file state to where we were */
set_file_offset(f, z->page_start);
return 1;
/* restore file state to where we were */
bail:
set_file_offset(f, z->page_start);
return 0;
}
static int vorbis_seek_frame_from_page(stb_vorbis *f, uint32_t page_start, uint32_t first_sample, uint32_t target_sample, int fine)
{
int left_start, left_end, right_start, right_end, mode,i;
int frame=0;
uint32_t frame_start;
int frames_to_skip, data_to_skip;
/* first_sample is the sample # of the first sample that doesn't
* overlap the previous page... note that this requires us to
* _partially_ discard the first packet! bleh. */
set_file_offset(f, page_start);
f->next_seg = -1; /* force page resync */
frame_start = first_sample;
/* frame start is where the previous packet's last decoded sample
* was, which corresponds to left_end... EXCEPT if the previous
* packet was long and this packet is short? Probably a bug here.
* now, we can start decoding frames... we'll only FAKE decode them,
* until we find the frame that contains our sample; then we'll rewind,
* and try again */
for (;;) {
int start;
if (!vorbis_decode_initial(f, &left_start, &left_end, &right_start, &right_end, &mode))
return error(f, VORBIS_seek_failed);
if (frame == 0)
start = left_end;
else
start = left_start;
/* the window starts at left_start; the last valid sample we generate
* before the next frame's window start is right_start-1 */
if (target_sample < frame_start + right_start-start)
break;
flush_packet(f);
if (f->eof)
return error(f, VORBIS_seek_failed);
frame_start += right_start - start;
++frame;
}
/* ok, at this point, the sample we want is contained in frame #'frame'
* to decode frame #'frame' normally, we have to decode the
* previous frame first... but if it's the FIRST frame of the page
* we can't. if it's the first frame, it means it falls in the part
* of the first frame that doesn't overlap either of the other frames.
* so, if we have to handle that case for the first frame, we might
* as well handle it for all of them, so: */
if (target_sample > frame_start + (left_end - left_start)) {
/* so what we want to do is go ahead and just immediately decode
* this frame, but then make it so the next get_frame_float() uses
* this already-decoded data? or do we want to go ahead and rewind,
* and leave a flag saying to skip the first N data? let's do that
*/
frames_to_skip = frame; /* if this is frame #1, skip 1 frame (#0) */
data_to_skip = left_end - left_start;
} else {
/* otherwise, we want to skip frames 0, 1, 2, ... frame-2
* (which means frame-2+1 total frames) then decode frame-1,
* then leave frame pending */
frames_to_skip = frame - 1;
assert(frames_to_skip >= 0);
data_to_skip = -1;
}
set_file_offset(f, page_start);
f->next_seg = - 1; /* force page resync */
for (i=0; i < frames_to_skip; ++i) {
maybe_start_packet(f);
flush_packet(f);
}
if (data_to_skip >= 0) {
int i,j,n = f->blocksize_0 >> 1;
f->discard_samples_deferred = data_to_skip;
for (i=0; i < f->channels; ++i)
for (j=0; j < n; ++j)
f->previous_window[i][j] = 0;
f->previous_length = n;
frame_start += data_to_skip;
} else {
f->previous_length = 0;
vorbis_pump_first_frame(f);
}
/* at this point, the NEXT decoded frame will generate the desired sample */
if (fine) {
/* so if we're doing sample accurate streaming, we want to go ahead and decode it! */
if (target_sample != frame_start) {
int n;
stb_vorbis_get_frame_float(f, &n, NULL);
assert(target_sample > frame_start);
assert(f->channel_buffer_start + (int) (target_sample-frame_start) < f->channel_buffer_end);
f->channel_buffer_start += (target_sample - frame_start);
}
}
return 0;
}
static int vorbis_seek_base(stb_vorbis *f, unsigned int sample_number, int fine)
{
ProbedPage p[2],q;
if (IS_PUSH_MODE(f)) return error(f, VORBIS_invalid_api_mixing);
/* do we know the location of the last page? */
if (f->p_last.page_start == 0) {
uint32_t z = stb_vorbis_stream_length_in_samples(f);
if (z == 0) return error(f, VORBIS_cant_find_last_page);
}
p[0] = f->p_first;
p[1] = f->p_last;
if (sample_number >= f->p_last.last_decoded_sample)
sample_number = f->p_last.last_decoded_sample-1;
if (sample_number < f->p_first.last_decoded_sample) {
vorbis_seek_frame_from_page(f, p[0].page_start, 0, sample_number, fine);
return 0;
} else {
int attempts=0;
while (p[0].page_end < p[1].page_start) {
uint32_t probe;
uint32_t start_offset, end_offset;
uint32_t start_sample, end_sample;
/* copy these into local variables so we can tweak them
* if any are unknown */
start_offset = p[0].page_end;
end_offset = p[1].after_previous_page_start; /* an address known to seek to page p[1] */
start_sample = p[0].last_decoded_sample;
end_sample = p[1].last_decoded_sample;
/* currently there is no such tweaking logic needed/possible? */
if (start_sample == SAMPLE_unknown || end_sample == SAMPLE_unknown)
return error(f, VORBIS_seek_failed);
/* now we want to lerp between these for the target samples... */
/* step 1: we need to bias towards the page start... */
if (start_offset + 4000 < end_offset)
end_offset -= 4000;
/* now compute an interpolated search loc */
probe = start_offset + (int) floor((float) (end_offset - start_offset) / (end_sample - start_sample) * (sample_number - start_sample));
/* next we need to bias towards binary search...
* code is a little wonky to allow for full 32-bit unsigned values */
if (attempts >= 4) {
uint32_t probe2 = start_offset + ((end_offset - start_offset) >> 1);
if (attempts >= 8)
probe = probe2;
else if (probe < probe2)
probe = probe + ((probe2 - probe) >> 1);
else
probe = probe2 + ((probe - probe2) >> 1);
}
++attempts;
set_file_offset(f, probe);
if (!vorbis_find_page(f, NULL, NULL)) return error(f, VORBIS_seek_failed);
if (!vorbis_analyze_page(f, &q)) return error(f, VORBIS_seek_failed);
q.after_previous_page_start = probe;
/* it's possible we've just found the last page again */
if (q.page_start == p[1].page_start) {
p[1] = q;
continue;
}
if (sample_number < q.last_decoded_sample)
p[1] = q;
else
p[0] = q;
}
if (p[0].last_decoded_sample <= sample_number && sample_number < p[1].last_decoded_sample) {
vorbis_seek_frame_from_page(f, p[1].page_start, p[0].last_decoded_sample, sample_number, fine);
return 0;
}
return error(f, VORBIS_seek_failed);
}
}
int stb_vorbis_seek_frame(stb_vorbis *f, unsigned int sample_number)
{
return vorbis_seek_base(f, sample_number, FALSE);
}
int stb_vorbis_seek(stb_vorbis *f, unsigned int sample_number)
{
return vorbis_seek_base(f, sample_number, TRUE);
}
void stb_vorbis_seek_start(stb_vorbis *f)
{
if (IS_PUSH_MODE(f)) { error(f, VORBIS_invalid_api_mixing); return; }
set_file_offset(f, f->first_audio_page_offset);
f->previous_length = 0;
f->first_decode = TRUE;
f->next_seg = -1;
vorbis_pump_first_frame(f);
}
unsigned int stb_vorbis_stream_length_in_samples(stb_vorbis *f)
{
unsigned int restore_offset, previous_safe;
unsigned int end, last_page_loc;
if (IS_PUSH_MODE(f)) return error(f, VORBIS_invalid_api_mixing);
if (!f->total_samples) {
unsigned int last;
uint32_t lo,hi;
char header[6];
/* first, store the current decode position so we can restore it */
restore_offset = stb_vorbis_get_file_offset(f);
/* now we want to seek back 64K from the end (the last page must
* be at most a little less than 64K, but let's allow a little slop) */
if (f->stream_len >= 65536 && f->stream_len-65536 >= f->first_audio_page_offset)
previous_safe = f->stream_len - 65536;
else
previous_safe = f->first_audio_page_offset;
set_file_offset(f, previous_safe);
/* previous_safe is now our candidate 'earliest known place that seeking
* to will lead to the final page' */
if (!vorbis_find_page(f, &end, &last)) {
/* if we can't find a page, we're hosed! */
f->error = VORBIS_cant_find_last_page;
f->total_samples = 0xffffffff;
goto done;
}
/* check if there are more pages */
last_page_loc = stb_vorbis_get_file_offset(f);
/* stop when the last_page flag is set, not when we reach eof;
* this allows us to stop short of a 'file_section' end without
* explicitly checking the length of the section */
while (!last) {
set_file_offset(f, end);
if (!vorbis_find_page(f, &end, &last)) {
/* the last page we found didn't have the 'last page' flag
* set. whoops! */
break;
}
previous_safe = last_page_loc+1;
last_page_loc = stb_vorbis_get_file_offset(f);
}
set_file_offset(f, last_page_loc);
/* parse the header */
getn(f, (unsigned char *)header, 6);
/* extract the absolute granule position */
lo = get32(f);
hi = get32(f);
if (lo == 0xffffffff && hi == 0xffffffff) {
f->error = VORBIS_cant_find_last_page;
f->total_samples = SAMPLE_unknown;
goto done;
}
if (hi)
lo = 0xfffffffe; /* saturate */
f->total_samples = lo;
f->p_last.page_start = last_page_loc;
f->p_last.page_end = end;
f->p_last.last_decoded_sample = lo;
f->p_last.first_decoded_sample = SAMPLE_unknown;
f->p_last.after_previous_page_start = previous_safe;
done:
set_file_offset(f, restore_offset);
}
return f->total_samples == SAMPLE_unknown ? 0 : f->total_samples;
}
float stb_vorbis_stream_length_in_seconds(stb_vorbis *f)
{
return stb_vorbis_stream_length_in_samples(f) / (float) f->sample_rate;
}
int stb_vorbis_get_frame_float(stb_vorbis *f, int *channels, float ***output)
{
int len, right,left,i;
if (IS_PUSH_MODE(f)) return error(f, VORBIS_invalid_api_mixing);
if (!vorbis_decode_packet(f, &len, &left, &right)) {
f->channel_buffer_start = f->channel_buffer_end = 0;
return 0;
}
len = vorbis_finish_frame(f, len, left, right);
for (i=0; i < f->channels; ++i)
f->outputs[i] = f->channel_buffers[i] + left;
f->channel_buffer_start = left;
f->channel_buffer_end = left+len;
if (channels) *channels = f->channels;
if (output) *output = f->outputs;
return len;
}
stb_vorbis * stb_vorbis_open_memory(const unsigned char *data, int len, int *error, stb_vorbis_alloc *alloc)
{
stb_vorbis *f, p;
if (data == NULL) return NULL;
vorbis_init(&p, alloc);
p.stream = (uint8_t *) data;
p.stream_end = (uint8_t *) data + len;
p.stream_start = (uint8_t *) p.stream;
p.stream_len = len;
p.push_mode = FALSE;
if (start_decoder(&p)) {
f = vorbis_alloc(&p);
if (f) {
*f = p;
vorbis_pump_first_frame(f);
return f;
}
}
if (error) *error = p.error;
vorbis_deinit(&p);
return NULL;
}
int stb_vorbis_get_samples_float_interleaved(stb_vorbis *f, int channels, float *buffer, int num_floats)
{
float **outputs;
int len = num_floats / channels;
int n=0;
int z = f->channels;
if (z > channels) z = channels;
while (n < len) {
int i,j;
int k = f->channel_buffer_end - f->channel_buffer_start;
if (n+k >= len) k = len - n;
for (j=0; j < k; ++j) {
for (i=0; i < z; ++i)
*buffer++ = f->channel_buffers[i][f->channel_buffer_start+j];
for ( ; i < channels; ++i)
*buffer++ = 0;
}
n += k;
f->channel_buffer_start += k;
if (n == len)
break;
if (!stb_vorbis_get_frame_float(f, NULL, &outputs))
break;
}
return n;
}
int stb_vorbis_get_samples_float(stb_vorbis *f, int channels, float **buffer, int num_samples)
{
float **outputs;
int n=0;
int z = f->channels;
if (z > channels) z = channels;
while (n < num_samples) {
int i;
int k = f->channel_buffer_end - f->channel_buffer_start;
if (n+k >= num_samples) k = num_samples - n;
if (k) {
for (i=0; i < z; ++i)
memcpy(buffer[i]+n, f->channel_buffers[i]+f->channel_buffer_start, sizeof(float)*k);
for ( ; i < channels; ++i)
memset(buffer[i]+n, 0, sizeof(float) * k);
}
n += k;
f->channel_buffer_start += k;
if (n == num_samples)
break;
if (!stb_vorbis_get_frame_float(f, NULL, &outputs))
break;
}
return n;
}
#endif /* STB_VORBIS_NO_PULLDATA_API */
#endif /* STB_VORBIS_HEADER_ONLY */