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64
technology/applications/media/MKVToolnix.md
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@ -80,36 +80,36 @@ CHAPTER03NAME=Alice rocks the house
| `--stop-after-video-ends` | Stops processing after the primary video track ends, discarding any remaining packets of other tracks. |
#### Attachment Options
| Option | Description |
| ------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `--attachment-description description` | Plain text description of the following attachment. Applies to the next `--attach-file` or `--attach-file-once` option. |
| `--attachment-mime-type MIME type` | [MIME](../../files/MIME.md) type of the following attachment. |
| `--attachment-name name` | Sets the name that will be stored in the output file for this attachment. |
| Option | Description |
| ------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `--attachment-description description` | Plain text description of the following attachment. Applies to the next `--attach-file` or `--attach-file-once` option. |
| `--attachment-mime-type MIME type` | [MIME](../../files/MIME.md) type of the following attachment. |
| `--attachment-name name` | Sets the name that will be stored in the output file for this attachment. |
| `--attach-file file-name, --attach-file-once file-name` | Creates a file attachment inside the [Matroska](../../files/media/Matroska.md) file. The [MIME](../../files/MIME.md) type must have been set before this option can used. |
#### Input File Options
| Option | Description |
| ------------------------------------------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `-a, --audio-tracks [!]n,m,...` | Copy the audio tracks `n`, `m` etc. The numbers are track IDs which can be obtained with the `--identify` switch. Instead of track IDs you can also provide ISO 639-2 language codes. This will only work for source files that provide language tags for their tracks. They're not simply the track numbers. Default: copy all audio tracks. If the IDs are prefixed with `!` then the meaning is reversed: copy all tracks of this kind but the ones listed after the `!`. |
| `-d, --video-tracks [!]n,m,...` | Copy the video tracks `n`, `m` etc. The numbers are track IDs which can be obtained with the `--identify` switch. They're not simply the track numbers. Default: copy all video tracks. Instead of track IDs you can also provide ISO 639-2 language codes. This will only work for source files that provide language tags for their tracks. If the IDs are prefixed with `!` then the meaning is reversed: copy all tracks of this kind but the ones listed after the `!`. |
| `-s, --subtitle-tracks [!]n,m,...` | Copy the subtitle tracks `n`, `m` etc. The numbers are track IDs which can be obtained with the `--identify` switch. They're not simply the track numbers. Default: copy all subtitle tracks. Instead of track IDs you can also provide ISO 639-2 language codes. This will only work for source files that provide language tags for their tracks. If the IDs are prefixed with `!` then the meaning is reversed: copy all tracks of this kind but the ones listed after the `!`. |
| `--track-tags [!]n,m,...` | Copy the tags for tracks `n`, `m` etc. The numbers are track IDs which can be obtained with the `--identify` switch. They're not simply the track numbers. Default: copy tags for all tracks. If the IDs are prefixed with `!` then the meaning is reversed: copy everything but the IDs listed after the `!`. |
| `-m, --attachments [!]n[:all/first],m[:all|first],...` | Copy the attachments with the IDs n, m etc to all or only the first output file. Each ID can be followed by either `:all` (which is the default if neither is entered) or `:first`. If splitting is active then those attachments whose IDs are specified with `:all` are copied to all of the resulting output files while the others are only copied into the first output file. If splitting is not active then both variants have the same effect. The default is to copy all attachments to all output files. If the IDs are prefixed with `!` then the meaning is reversed: copy everything but the IDs listed after the `!`. |
| `-A, --no-audio` | Don't copy any audio track from this file. |
| `-D, --no-video` | Don't copy any video track from this file. |
| `-S, --no-subtitles` | Don't copy any subtitle track from this file. |
| `-T, --no-track-tags` | Don't copy any track specific tags from this file. |
| `--no-chapters` | Don't copy chapters from this file. |
| `-M, --no-attachments` | Don't copy attachments from this file. |
| `--no-global-tags` | Don't copy global tags from this file. |
| `-y, --sync TID:d[,o[/p]]` | Adjust the timestamps of the track with the id `TID` by `d` ms. The track IDs are the same as the ones given with `--identify`. `o/p`: adjust the timestamps by `o/p` to fix linear drifts. `p` defaults to 1 if omitted. Both `o` and `p` can be floating point numbers. |
| `--default-track-flag TID[:bool]` | Sets the "default track" flag for the given track if the optional argument `bool` is set to 1 or if it isn't present. The flag will be set if the source container doesn't provide that information and the user doesn't specify it via this option. |
| `--track-name TID:name` | Sets the track name for the given track to `name`. |
| `--language TID:language` | Sets the language for the given track. Both ISO 639-2 language codes and ISO 639-1 country codes are allowed. The country codes will be converted to language codes automatically. All languages including their ISO 639-2 codes can be listed with the `--list-languages` option. |
| Option | Description |
| ------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `-a, --audio-tracks [!]n,m,...` | Copy the audio tracks `n`, `m` etc. The numbers are track IDs which can be obtained with the `--identify` switch. Instead of track IDs you can also provide ISO 639-2 language codes. This will only work for source files that provide language tags for their tracks. They're not simply the track numbers. Default: copy all audio tracks. If the IDs are prefixed with `!` then the meaning is reversed: copy all tracks of this kind but the ones listed after the `!`. |
| `-d, --video-tracks [!]n,m,...` | Copy the video tracks `n`, `m` etc. The numbers are track IDs which can be obtained with the `--identify` switch. They're not simply the track numbers. Default: copy all video tracks. Instead of track IDs you can also provide ISO 639-2 language codes. This will only work for source files that provide language tags for their tracks. If the IDs are prefixed with `!` then the meaning is reversed: copy all tracks of this kind but the ones listed after the `!`. |
| `-s, --subtitle-tracks [!]n,m,...` | Copy the subtitle tracks `n`, `m` etc. The numbers are track IDs which can be obtained with the `--identify` switch. They're not simply the track numbers. Default: copy all subtitle tracks. Instead of track IDs you can also provide ISO 639-2 language codes. This will only work for source files that provide language tags for their tracks. If the IDs are prefixed with `!` then the meaning is reversed: copy all tracks of this kind but the ones listed after the `!`. |
| `--track-tags [!]n,m,...` | Copy the tags for tracks `n`, `m` etc. The numbers are track IDs which can be obtained with the `--identify` switch. They're not simply the track numbers. Default: copy tags for all tracks. If the IDs are prefixed with `!` then the meaning is reversed: copy everything but the IDs listed after the `!`. |
| `-m, --attachments [!]n[:all/first],m[:all | first],...` | Copy the attachments with the IDs n, m etc to all or only the first output file. Each ID can be followed by either `:all` (which is the default if neither is entered) or `:first`. If splitting is active then those attachments whose IDs are specified with `:all` are copied to all of the resulting output files while the others are only copied into the first output file. If splitting is not active then both variants have the same effect. The default is to copy all attachments to all output files. If the IDs are prefixed with `!` then the meaning is reversed: copy everything but the IDs listed after the `!`. |
| `-A, --no-audio` | Don't copy any audio track from this file. |
| `-D, --no-video` | Don't copy any video track from this file. |
| `-S, --no-subtitles` | Don't copy any subtitle track from this file. |
| `-T, --no-track-tags` | Don't copy any track specific tags from this file. |
| `--no-chapters` | Don't copy chapters from this file. |
| `-M, --no-attachments` | Don't copy attachments from this file. |
| `--no-global-tags` | Don't copy global tags from this file. |
| `-y, --sync TID:d[,o[/p]]` | Adjust the timestamps of the track with the id `TID` by `d` ms. The track IDs are the same as the ones given with `--identify`. `o/p`: adjust the timestamps by `o/p` to fix linear drifts. `p` defaults to 1 if omitted. Both `o` and `p` can be floating point numbers. |
| `--default-track-flag TID[:bool]` | Sets the "default track" flag for the given track if the optional argument `bool` is set to 1 or if it isn't present. The flag will be set if the source container doesn't provide that information and the user doesn't specify it via this option. |
| `--track-name TID:name` | Sets the track name for the given track to `name`. |
| `--language TID:language` | Sets the language for the given track. Both ISO 639-2 language codes and ISO 639-1 country codes are allowed. The country codes will be converted to language codes automatically. All languages including their ISO 639-2 codes can be listed with the `--list-languages` option. |
#### Video Input File Options
| Option | Description |
| ----------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| Option | Description |
| ----------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `--display-dimensions TID:widthxheight` | [Matroska](../../files/media/Matroska.md) files contain two values that set the display properties that a player should scale the image on playback to: display width and display height. These values can be set with this option, e.g. `1:640x480`. |
| `--aspect-ratio TID:ratio/(width/height)` | [Matroska](../../files/media/Matroska.md) files contain two values that set the display properties that a player should scale the image on playback to: display width and display height. With this option mkvmerge will automatically calculate the display width and display height based on the image's original width and height and the aspect ratio given with this option. The ratio can be given either as a floating point number `ratio` or as a fraction `width/height`, e.g. `16/9`. |
@ -118,11 +118,11 @@ CHAPTER03NAME=Alice rocks the house
| ------------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `-i, --identify file-name` | Will let mkvmerge probe the single file and report its type, the tracks contained in the file and their track IDs. If this option is used then the only other option allowed is the filename. |
| `-J file-name` | This is a convenient alias for `--identification-format json --identify file-name`. |
| `-F, --identification-format format` | Determines the output format used by the `--identify` option. The following formats are supported: `text` (the default) and `json`. |
| `-F, --identification-format format` | Determines the output format used by the `--identify` option. The following formats are supported: `text` (the default) and `json`. |
| `--list-languages` | Lists all languages and their ISO 639-2 code which can be used with the `--language` option. |
## mkvinfo
This program lists all elements contained in a [Matroska](../../files/media/Matroska.md). The output can be limited to a list of tracks in the file including information about the [codecs](../../files/media/Codecs.md) used.
This program lists all elements contained in a [Matroska](../../files/media/Matroska.md). The output can be limited to a list of tracks in the file including information about the codecs used.
Usage: `mkvinfo [options] {source-filename}`
### Options
@ -160,12 +160,12 @@ Usage: `mkvpropedit [options] {source-filename} {actions} `
| `-l, --list-property-names` | Lists all known and editable property names, their type (string, integer, boolean etc) and a short description. |
#### Track and segment info properties:
| Option | Description |
| ---------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Option | Description |
| ---------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `-e, --edit selector` | Sets the [Matroska](../../files/media/Matroska.md) file section (segment information or a certain track's headers) that all following add, set and delete actions operate on. This option can be used multiple times in order to make modifications to more than one element.<br>This stays valid until the next `--edit` option is found<br>`selector` has the `track:n` format. |
| `-a, --add name=value` | Adds a property `name` with the value `value`. The property will be added even if such a property exists already. Note that most properties are unique and cannot occur more than once. |
| `-s, --set name=value` | Sets all occurrences of the property `name` to the value `value`. If no such property exists then it will be added. |
| `-d, --delete name` | Deletes all occurrences of the property `name`. Note that some properties are required and cannot be deleted. |
| `-a, --add name=value` | Adds a property `name` with the value `value`. The property will be added even if such a property exists already. Note that most properties are unique and cannot occur more than once. |
| `-s, --set name=value` | Sets all occurrences of the property `name` to the value `value`. If no such property exists then it will be added. |
| `-d, --delete name` | Deletes all occurrences of the property `name`. Note that some properties are required and cannot be deleted. |
#### Tags and chapters
| Option | Description |

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@ -5,8 +5,9 @@ os:
website: https://mpv.io
flatpak-id: io.mpv.Mpv
---
# MPV
mpv is a based media player. It supports a wide variety of video [file formats](../../files/MIME.md), audio and video [codecs](../../files/media/Codecs.md), and subtitle types. Special input [URL](../../internet/URL.md) types are available to read input from a variety of sources other than disk files. Depending on platform, a variety of different video and audio output methods are supported.
mpv is a based media player. It supports a wide variety of video [file formats](../../files/MIME.md), audio and video codecs, and subtitle types. Special input [URL](../../internet/URL.md) types are available to read input from a variety of sources other than disk files. Depending on platform, a variety of different video and audio output methods are supported.
## Usage
Usage: `mpv [options] [file|URL|PLAYLIST|-]`
@ -454,7 +455,7 @@ You can encode files from one format/codec to another using this facility. This
- `--of=<format>`
Specifies the output format (overrides autodetection by the file name extension of the file specified by `-o`). See `--of=help` for a full list of supported formats.
- `--oac=<codec>`
Specifies the output audio codec. See `--oac=help` for a full list of supported [codecs](../../files/media/Codecs.md).
Specifies the output audio codec. See `--oac=help` for a full list of supported codecs.
- `--oacopts=<options>`
Specifies the output audio codec options for libavcodec. See `--oacopts=help` for a full list of supported options.
Example:
@ -463,7 +464,7 @@ You can encode files from one format/codec to another using this facility. This
--oac=libmp3lame --oacopts=b=128000
```
- `--ovc=<codec>`
Specifies the output video codec. See `--ovc=help` for a full list of supported [codecs](../../files/media/Codecs.md).
Specifies the output video codec. See `--ovc=help` for a full list of supported codecs.
- `--ovcopts=<options>`
Specifies the output video codec options for libavcodec. See `--ovcopts=help` for a full list of supported options.

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@ -20,29 +20,29 @@ ffmpeg -i INPUT.mp4 OUTPUT.mkv
Usage: `ffmpeg [global_options] {[input_file_options] -i input_url} ... {[output_file_options] output_url} ... `
### Options
| Option | Description |
| ----------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `-i [input]` | Input a file |
| `-map [input]:[stream]` | Map input streams |
| `-c:[stream]:[input], -codec:[stream]:[input] [codec]` | Specify codec. If `codec` is `copy` stream will not be reencoded. |
| `-t duration (input/output)` | When used as an input option (before `-i`), limit the duration of data read from the input file. |
| `-to position (input/output)` | Stop writing the output or reading the input at position. |
| `-ss position (input/output)` | When used as an input option (before `-i`), seeks in this input file to position. Note that in most formats it is not possible to seek exactly, so ffmpeg will seek to the closest seek point before position. |
| `-sseof position (input)` | Like the `-ss` option but relative to the "end of file". That is negative values are earlier in the file, 0 is at EOF. |
| `-itsoffset offset (input)` | Set the input time offset.<br>offset must be a time duration specification.<br>The offset is added to the timestamps of the input files. Specifying a positive offset means that the corresponding streams are delayed by the time duration specified in offset. |
| `-itsscale scale (input,per-stream)` | Rescale input timestamps. scale should be a floating point number. |
| `-timestamp date (output)` | Set the recording timestamp in the container.<br>date must be a date specification. |
| `-metadata[:metadata_specifier] key=value (output,per-metadata)` | Set a metadata key/value pair.<br>An optional metadata_specifier may be given to set metadata on streams, chapters or programs.<br>This option overrides metadata set with `-map_metadata`. It is also possible to delete metadata by using an empty value.<br>For example, for setting the title in the output file: `ffmpeg -i in.avi -metadata title="my title" out.flv`<br>To set the language of the first audio stream: `ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT` |
| `-filter[:stream_specifier] filtergraph (output,per-stream)` | Create the filtergraph specified by filtergraph and use it to filter the stream. |
| `-frames[:stream_specifier] framecount (output,per-stream)` | Stop writing to the stream after framecount frames. |
| `-q[:stream_specifier] q (output,per-stream), -qscale[:stream_specifier] q (output,per-stream)` | Use fixed quality scale (VBR). The meaning of q/qscale is codec-dependent. If qscale is used without a stream_specifier then it applies only to the video stream, this is to maintain compatibility with previous behavior and as specifying the same codec specific value to 2 different [codecs](../../files/media/Codecs.md) that is audio and video generally is not what is intended when no stream_specifier is used. |
| Option | Description |
| ----------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `-i [input]` | Input a file |
| `-map [input]:[stream]` | Map input streams |
| `-c:[stream]:[input], -codec:[stream]:[input] [codec]` | Specify codec. If `codec` is `copy` stream will not be reencoded. |
| `-t duration (input/output)` | When used as an input option (before `-i`), limit the duration of data read from the input file. |
| `-to position (input/output)` | Stop writing the output or reading the input at position. |
| `-ss position (input/output)` | When used as an input option (before `-i`), seeks in this input file to position. Note that in most formats it is not possible to seek exactly, so ffmpeg will seek to the closest seek point before position. |
| `-sseof position (input)` | Like the `-ss` option but relative to the "end of file". That is negative values are earlier in the file, 0 is at EOF. |
| `-itsoffset offset (input)` | Set the input time offset.<br>offset must be a time duration specification.<br>The offset is added to the timestamps of the input files. Specifying a positive offset means that the corresponding streams are delayed by the time duration specified in offset. |
| `-itsscale scale (input,per-stream)` | Rescale input timestamps. scale should be a floating point number. |
| `-timestamp date (output)` | Set the recording timestamp in the container.<br>date must be a date specification. |
| `-metadata[:metadata_specifier] key=value (output,per-metadata)` | Set a metadata key/value pair.<br>An optional metadata_specifier may be given to set metadata on streams, chapters or programs.<br>This option overrides metadata set with `-map_metadata`. It is also possible to delete metadata by using an empty value.<br>For example, for setting the title in the output file: `ffmpeg -i in.avi -metadata title="my title" out.flv`<br>To set the language of the first audio stream: `ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT` |
| `-filter[:stream_specifier] filtergraph (output,per-stream)` | Create the filtergraph specified by filtergraph and use it to filter the stream. |
| `-frames[:stream_specifier] framecount (output,per-stream)` | Stop writing to the stream after framecount frames. |
| `-q[:stream_specifier] q (output,per-stream), -qscale[:stream_specifier] q (output,per-stream)` | Use fixed quality scale (VBR). The meaning of q/qscale is codec-dependent. If qscale is used without a stream_specifier then it applies only to the video stream, this is to maintain compatibility with previous behavior and as specifying the same codec specific value to 2 different codecs that is audio and video generally is not what is intended when no stream_specifier is used. |
| `-attach filename (output)` | Add an attachment to the output file. This is supported by a few formats like [Matroska](../../files/media/Matroska.md) for e.g. fonts used in rendering subtitles. Attachments are implemented as a specific type of stream, so this option will add a new stream to the file. It is then possible to use per-stream options on this stream in the usual way. Attachment streams created with this option will be created after all the other streams (i.e. those created with `-map`or automatic mappings). <br>Note that for Matroska you also have to set the mimetype metadata tag: `ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv` |
| `-dump_attachment[:stream_specifier] filename (input,per-stream)` | Extract the matching attachment stream into a file named filename. If filename is empty, then the value of the filename metadata tag will be used. <br>E.g. to extract the first attachment to a file named ’out.ttf’: `ffmpeg -dump_attachment:t:0 out.ttf -i INPUT`<br>To extract all attachments to files determined by the filename tag: `ffmpeg -dump_attachment:t "" -i INPUT` |
| `-dump_attachment[:stream_specifier] filename (input,per-stream)` | Extract the matching attachment stream into a file named filename. If filename is empty, then the value of the filename metadata tag will be used. <br>E.g. to extract the first attachment to a file named ’out.ttf’: `ffmpeg -dump_attachment:t:0 out.ttf -i INPUT`<br>To extract all attachments to files determined by the filename tag: `ffmpeg -dump_attachment:t "" -i INPUT` |
### Video Options
| Option | Description |
| -------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `-r[:stream_specifier] fps (input/output,per-stream)` | Set frame rate (Hz value, fraction or abbreviation). |
| `-r[:stream_specifier] fps (input/output,per-stream)` | Set frame rate (Hz value, fraction or abbreviation). |
| `-aspect[:stream_specifier] aspect (output,per-stream)` | Set the video display aspect ratio specified by aspect.<br>aspect can be a floating point number string, or a string of the form num:den, where num and den are the numerator and denominator of the aspect ratio. For example "4:3", "16:9", "1.3333", and "1.7777" are valid argument values.<br>If used together with -vcodec copy, it will affect the aspect ratio stored at container level, but not the aspect ratio stored in encoded frames, if it exists. |
| `-pix_fmt[:stream_specifier] format (input/output,per-stream)` | Set pixel format. Use -pix_fmts to show all the supported pixel formats. If the selected pixel format can not be selected, ffmpeg will print a warning and select the best pixel format supported by the encoder. If pix_fmt is prefixed by a +, ffmpeg will exit with an error if the requested pixel format can not be selected, and automatic conversions inside filtergraphs are disabled. If pix_fmt is a single +, ffmpeg selects the same pixel format as the input (or graph output) and automatic conversions are disabled. |
@ -55,7 +55,7 @@ Usage: `ffmpeg [global_options] {[input_file_options] -i input_url} ... {[output
### Advanced Options
| Option | Description |
| ----------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `-ignore_unknown` | Ignore input streams with unknown type instead of failing if copying such streams is attempted. |
| `-ignore_unknown` | Ignore input streams with unknown type instead of failing if copying such streams is attempted. |
| `-copy_unknown` | Allow input streams with unknown type to be copied instead of failing if copying such streams is attempted. |
| `-map_chapters input_file_index (output)` | Copy chapters from input file with index input_file_index to the next output file. If no chapter mapping is specified, then chapters are copied from the first input file with at least one chapter. Use a negative file index to disable any chapter copying. |
@ -218,7 +218,7 @@ Usage: `ffprobe [options] [input]`
| Option | Description |
| ----------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `-hide_banner` | Suppress printing banner. |
| `-output_format, -of, -print_format writer_name[=writer_options]` | Set the output printing format.<br> writer_name specifies the name of the writer, and writer_options specifies the options to be passed to the writer.<br>For example for printing the output in [JSON](../../files/JSON.md) format, specify:<br>`-output_format json` |
| `-output_format, -of, -print_format writer_name[=writer_options]` | Set the output printing format.<br> writer_name specifies the name of the writer, and writer_options specifies the options to be passed to the writer.<br>For example for printing the output in [JSON](../../files/JSON.md) format, specify:<br>`-output_format json` |
| `-select_streams stream_specifier` | Select only the streams specified by stream_specifier. This option affects only the options related to streams (e.g. show_streams, show_packets, etc.).<br>For example to show only audio streams, you can use the command:<br>`ffprobe -show_streams -select_streams a INPUT`<br>To show only video packets belonging to the video stream with index 1:<br>`ffprobe -show_packets -select_streams v:1 INPUT` |
| `-show_error` | Show information about the error found when trying to probe the input.<br>The error information is printed within a section with name "ERROR". |
| `-show_format` | Show information about the container format of the input multimedia stream.<br>All the container format information is printed within a section with name "FORMAT". |

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technology/files/media/Codecs.md
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@ -1,19 +0,0 @@
---
tags: ["meta"]
obj: meta/collection
---
# List of Codecs
## Video
- [H.264](video/H.264.md)
- [H.265](video/H.265.md)
- [VP9](video/VP9.md)
- [AV1](video/AV1.md)
## Audio
- [Opus](audio/Opus.md)
- [FLAC](audio/FLAC.md)
- [WAV](audio/WAV.md)
## Images
- [PNG](image/PNG.md)
- [AVIF](image/AVIF.md)

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technology/files/media/audio/Opus.md
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@ -6,7 +6,7 @@ obj: codec
# Opus
Opus is a lossy audio coding format developed by the Xiph.Org Foundation and standardized by the Internet Engineering Task Force, designed to efficiently code speech and general audio in a single format, while remaining low-latency enough for real-time interactive communication and low-complexity enough for low-end embedded processors. Opus replaces both Vorbis and Speex for new applications, and several blind listening tests have ranked it higher-quality than any other standard audio format at any given bitrate until transparency is reached, including MP3, AAC, and HE-AAC.
Opus combines the speech-oriented LPC-based SILK algorithm and the lower-latency MDCT-based CELT algorithm, switching between or combining them as needed for maximal efficiency. Bitrate, audio bandwidth, complexity, and algorithm can all be adjusted seamlessly in each frame. Opus has the low algorithmic delay (26.5 ms by default) necessary for use as part of a real-time communication link, networked music performances, and live lip sync; by trading-off quality or bitrate, the delay can be reduced down to 5 ms. Its delay is exceptionally low compared to competing [codecs](../Codecs.md), which require well over 100 ms, yet Opus performs very competitively with these formats in terms of quality per bitrate.
Opus combines the speech-oriented LPC-based SILK algorithm and the lower-latency MDCT-based CELT algorithm, switching between or combining them as needed for maximal efficiency. Bitrate, audio bandwidth, complexity, and algorithm can all be adjusted seamlessly in each frame. Opus has the low algorithmic delay (26.5 ms by default) necessary for use as part of a real-time communication link, networked music performances, and live lip sync; by trading-off quality or bitrate, the delay can be reduced down to 5 ms. Its delay is exceptionally low compared to competing codecs, which require well over 100 ms, yet Opus performs very competitively with these formats in terms of quality per bitrate.
As an open format standardized through RFC 6716, a reference implementation called libopus is available under the New BSD License. The reference has both fixed-point and floating-point optimizations for low- and high-end devices, with SIMD optimizations on platforms that support them. All known software patents that cover Opus are licensed under royalty-free terms. Opus is widely used as the voice-over-IP (VoIP) codec in applications such as Discord, WhatsApp, and the PlayStation 4.

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technology/files/media/video/AV1.md
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# AV1
#refactor -> add encoding options av1an,
AV1 is a royalty-free video codec designed to be an alternative to the widely used [H.264](H.264.md) and HEVC [codecs](../Codecs.md). It was developed by the Alliance for Open Media, a consortium of technology companies including Google, Mozilla, and Netflix.
#refactor -> add encoding options av1an
AV1 is a royalty-free video codec designed to be an alternative to the widely used [H.264](H.264.md) and HEVC codecs. It was developed by the Alliance for Open Media, a consortium of technology companies including Google, Mozilla, and Netflix.
Encoding can be done with [ffmpeg](../../../applications/media/ffmpeg.md) or av1an.
## Key Features
AV1 includes a range of features designed to provide high-quality video compression while remaining open and accessible to all users:
- High compression efficiency: AV1 is designed to provide high-quality video compression while using less bandwidth than other [codecs](../Codecs.md). This makes it ideal for streaming video over the internet.
- High compression efficiency: AV1 is designed to provide high-quality video compression while using less bandwidth than other codecs. This makes it ideal for streaming video over the internet.
- Scalable video technology: AV1 includes scalable video technology that allows it to adjust the quality of video based on available bandwidth. This ensures that users always receive the best possible video quality for their network connection.
- Royalty-free: Unlike other [codecs](../Codecs.md), AV1 is completely royalty-free. This means that anyone can use it without having to pay fees or royalties.
- Royalty-free: Unlike other codecs, AV1 is completely royalty-free. This means that anyone can use it without having to pay fees or royalties.
- Wide range of applications: AV1 is suitable for a wide range of applications, including live streaming, video-on-demand services, and video conferencing.
- Open and accessible: AV1 is an open standard, meaning that anyone can use it and contribute to its development. This makes it accessible to users of all skill levels.
## Advantages
AV1 offers a number of advantages over other video [codecs](../Codecs.md):
- Higher quality video: AV1 provides higher quality video than other [codecs](../Codecs.md), even at lower bitrates.
- More efficient compression: AV1 provides more efficient compression than other [codecs](../Codecs.md), allowing for faster download and upload times.
- Better streaming performance: AV1 is designed for streaming video over the internet, and provides better streaming performance than other [codecs](../Codecs.md).
AV1 offers a number of advantages over other video codecs:
- Higher quality video: AV1 provides higher quality video than other codecs, even at lower bitrates.
- More efficient compression: AV1 provides more efficient compression than other codecs, allowing for faster download and upload times.
- Better streaming performance: AV1 is designed for streaming video over the internet, and provides better streaming performance than other codecs.
- Wide compatibility: AV1 is compatible with a wide range of devices and platforms, including desktop and mobile devices.