A cross-platform framework to streamline encoding.

Easy, Fast, Efficient and Feature Rich

An easy way to start using AV1 / HEVC / H264 / VP9 / VP8 encoding. AOM, RAV1E, SVT-AV1, SVT-VP9, VPX, x265, x264 are supported.

Example with default parameters:

av1an -i input

With your own parameters:

av1an -i input -enc aom -v "--cpu-used=3 --end-usage=q --cq-level=30 --threads=8" -w 10
--split_method aom_keyframes --target_quality 95 --vmaf_path "vmaf_v0.6.1.pkl"
-min_q 20 -max_q 60 -ff "-vf scale=-1:1080" -a "-c:a libopus -ac 2 -b:a 192k"
-s scenes.csv -log my_log -o output


-i   --input            Input file(s), or Vapoursynth (.py,.vpy) script
                        (relative or absolute path)

-o   --output_file      Name/Path for output file (Default: (input file name)_(encoder).mkv)
                        Output file ending is always `.mkv`

-enc --encoder          Encoder to use
                        (`aom`,`rav1e`,`svt_av1`,`vpx`,`x265`, `x264`)
                        Default: aom
                        Example: -enc rav1e

-v   --video_params     Encoder settings flags (If not set, will be used default parameters.)
                        Must be inside ' ' or " "

-p   --passes           Set number of passes for encoding
                        (Default: AOMENC: 2, rav1e: 1, SVT-AV1: 1, SVT-VP9: 1,
                        VPX: 2, x265: 1, x264: 1)

-w   --workers          Override number of workers.

-r   --resume           If encode was stopped/quit resumes encode with saving all progress.
                        Resuming automatically skips scenedetection, audio encoding/copy,
                        splitting, so resuming only possible after actual encoding is started.
                        Temp folder must be present to resume.

--keep                  Doesn't delete temporary folders after encode has finished.

-q --quiet              Do not print a progress bar to the terminal.

-l --logging          Path to .log file(By default created in temp folder)

--temp                  Set path for the temporary folder. Default: .temp

--mkvmerge              Use mkvmerge for concatenating instead of FFmpeg.
                        Use when concatenation fails.

--webm                  Outputs webm file.
                        Use only if you're sure the source video and audio are compatible.

FFmpeg options

-a   --audio_params     FFmpeg audio settings (Default: copy audio from source to output)
                        Example: -a '-c:a libopus -b:a  64k'

-ff  --ffmpeg           FFmpeg options video options.
                        Applied to each encoding segment individually.
                        (Warning: Cropping doesn't work with Target VMAF mode
                        without specifying it in --vmaf_filter)
                        --ff " -vf scale=320:240 "

-fmt --pix_format       Setting custom pixel/bit format for piping
                        (Default: 'yuv420p10le')
                        Options should be adjusted accordingly, based on the encoder.


--split_method          Method used for generating splits.(Default: PySceneDetect)
                        Options: `pyscene`, `aom_keyframes`, `none`
                        `pyscene` - PyScenedetect, content based scenedetection
                        with threshold.
                        `aom_keyframes` - using stat file of 1 pass of aomenc encode
                        to get exact place where encoder will place new keyframes.
                        (Keep in mind that speed also depends on set aomenc parameters)
                        `ffmpeg` - Uses FFmpeg built in content based scene detection
                        with threshold. Slower and less precise than pyscene but requires
                        fewer dependencies.
                        `none` -  skips scenedetection. Useful for splitting by time

-cm  --chunk_method     Determine the method in which chunks are made for encoding.
                        By default the best method is selected automatically in this order:
                        vs_ffms2 > vs_lsmash > hybrid.
                        vs_ffms2 or vs_lsmash are recommended.
                        ['hybrid'(default), 'select', 'vs_ffms2', 'vs_lsmash']

-tr  --threshold        PySceneDetect threshold for scene detection Default: 35

-s   --scenes           Path to file with scenes timestamps.
                        If the file doesn't exist, a new file will be generated
                        in the current folder.
                        First run to generate stamps, all next reuse it.
                        Example: "-s scenes.csv"

-xs  --extra_split      Adding extra splits if frame distance between splits bigger than the
                        given value. Pair with none for time based splitting or with any
                        other splitting method to break up massive scenes.
                        Example: 1000 frames video with a single scene,
                        -xs 200 will add splits at 200,400,600,800.

--min_scene_len         Specifies the minimum number of frames in each split.

Target Quality

--target_quality        Quality value to target.
                        VMAF used as substructure for algorithms.
                        Supported in all encoders supported by Av1an.
                        Best works in range 85-97.
                        When using this mode, you must specify full encoding options.
                        These encoding options must include a quantizer based mode,
                        and some quantizer option provided. (This value will be replaced)
                        `--crf`,`--cq-level`,`--quantizer` etc

--target_quality_method Type of algorithm for use.
                        Options: per_shot

--min_q, --max_q        Min,Max Q values limits
                        If not set by the user, the default for encoder range will be used.

--vmaf                  Calculate VMAF after encoding is done and make a plot.

--vmaf_plots            Make plots for target quality search decisions
                        (Exception: early skips)
                        Saved in the temp folder by default.

--vmaf_path             Custom path to libvmaf models.
                        example: --vmaf_path "vmaf_v0.6.1.pkl"
                        Recommended to place both files in encoding folder
                        (`vmaf_v0.6.1.pkl` and `vmaf_v0.6.1.pkl.model`)
                        (Required if VMAF calculation doesn't work by default)

--vmaf_res              Resolution scaling for VMAF calculation,
                        vmaf_v0.6.1.pkl is 1920x1080 (by default),
                        vmaf_4k_v0.6.1.pkl is 3840x2160 (don't forget about vmaf_path)

--probes                Number of probes for interpolation.
                        1 and 2 probes have special cases to try to work with few data points.
                        The optimal level is 4-6 probes. Default: 4

--probe-slow            Use video encoding parameters for vmaf probes to get a more 
                        accurate Q at the cost of speed.

--vmaf_filter           Filter used for VMAF calculation. The passed format is filter_complex.
                        So if crop filter used ` -ff " -vf crop=200:1000:0:0 "`
                        `--vmaf_filter` must be : ` --vmaf_filter "crop=200:1000:0:0"`

--probing_rate          Setting rate for VMAF probes (Every N frame used in probe, Default: 4)

--n_threads             Limit number of threads that are used for VMAF calculation
                        Example: --n_threads 12
                        (Required if VMAF calculation gives error on high core counts)

Main Features

Splitting video by scenes for parallel encoding because AV1 encoders are currently not very good at multithreading and encoding is limited to a very limited number of threads.

  • PySceneDetect used for splitting video by scenes and running multiple encoders.
  • Vapoursynth script input support.
  • Fastest way to encode AV1 without losing quality, as fast as many CPU cores you have :).
  • Target Quality mode. Targeting end result reference visual quality. VMAF used as a substructure
  • Resuming encoding without loss of encoded progress.
  • Simple and clean console look.
  • Automatic detection of the number of workers the host can handle.
  • Builds the encoding queue with bigger files first, minimizing waiting for the last scene to encode.
  • Both video and audio transcoding with FFmpeg.
  • Logging of the progress of all encoders.