add ab-av1

technology/applications/Applications.md

@@ -325,6 +325,7 @@ rev: 2025-01-30
 - [artem](./media/artem.md)
 - [auto-palette-cli](./media/auto-palette-cli.md)
 - [metadata](./media/metadata-cli.md)
+- [ab-av1](./media/ab-av1.md)
 
 ## Network
 - [rclone](./network/rclone.md)

technology/applications/media/ab-av1.md

@@ -0,0 +1,75 @@
+---
+obj: application
+repo: https://github.com/alexheretic/ab-av1
+---
+
+# ab-av1
+AV1 video encoding tool with fast VMAF sampling & automatic encoder crf calculation. Uses [`ffmpeg`](./ffmpeg.md), `svt-av1` & `vmaf`.
+
+## Usage
+### Command: `auto-encode`
+Automatically determine the best crf to deliver the `--min-vmaf` and use it to encode a video or image.
+
+Two phases:
+- `crf-search` to determine the best `--crf` value
+- `ffmpeg` to encode using the settings
+
+```sh
+ab-av1 auto-encode [OPTIONS] -i <INPUT> --preset <PRESET> --min-vmaf <MIN_VMAF>
+```
+
+### Command: `crf-search`
+Interpolated binary search using sample-encode to find the best crf value delivering `--min-vmaf` & `--max-encoded-percent`.
+
+Outputs:
+- Best crf value
+- Mean sample VMAF score
+- Predicted full encode size
+- Predicted full encode time
+
+```sh
+ab-av1 crf-search [OPTIONS] -i <INPUT> --preset <PRESET> --min-vmaf <MIN_VMAF>
+```
+
+Notable options
+- `--min-xpsnr` <MIN_XPSNR> may be used as an alternative to VMAF.
+
+### Command: `sample-encode`
+Encode short video samples of an input using provided crf & preset. This is much quicker than full encode/vmaf run.
+
+Outputs:
+- Mean sample VMAF score
+- Predicted full encode size
+- Predicted full encode time
+
+```sh
+ab-av1 sample-encode [OPTIONS] -i <INPUT> --crf <CRF> --preset <PRESET>
+```
+
+Notable options
+- `--xpsnr` specifies calculation of XPSNR score instead of VMAF.
+
+### Command: `encode`
+Invoke `ffmpeg` to encode a video or image.
+
+```sh
+ab-av1 encode [OPTIONS] -i <INPUT> --crf <CRF> --preset <PRESET>
+```
+
+### Command: `vmaf`
+Full VMAF score calculation, distorted file vs reference file. Works with videos and images.
+
+- Auto sets model version (4k or 1k) according to resolution.
+- Auto sets n_threads to system threads.
+- Auto upscales lower resolution videos to the model.
+
+```sh
+ab-av1 vmaf --reference <REFERENCE> --distorted <DISTORTED>
+```
+
+### Command: `xpsnr`
+Full XPSNR score calculation, distorted file vs reference file. Works with videos and images.
+
+```sh
+ab-av1 xpsnr --reference <REFERENCE> --distorted <DISTORTED>
+```