Grav1synth

Grain Synth analyzer and editor for AV1 files

Build

• Prerequisites:
  • ffmpeg headers
  • Rust compiler
• Pull the repo
• Run cargo build --release
• Copy the binary from target/release/grav1synth to wherever you want

Usage

grav1synth inspect my_encode.mkv -o grain_file.txt

Reads my_encode.mkv and outputs a film grain table file at grain_file.txt

grav1synth apply my_encode.mkv -o grainy_encode.mkv -g grain_file.txt

Reads my_encode.mkv, adds film grain to it based on grain_file.txt, and outputs the video to grainy_encode.mkv

grav1synth generate my_encode.mkv -o grainy_encode.mkv --iso 400 --chroma

Reads my_encode.mkv, adds photon-noise-based film grain to it based on the strength provided by --iso (up to 6400), and outputs the video to grainy_encode.mkv. By default applies grain to only the luma plane. --chroma enables grain on chroma planes as well.

grav1synth remove my_encode.mkv -o clean_encode.mkv

Reads my_encode.mkv, removes all synthesized film grain, and outputs the video at clean_encode.mkv

grav1synth diff my_source.mkv denoised_source.mkv -o grain_file.txt

Compares my_source.mkv and denoised_source.mkv and generates a film grain table at grain_file.txt based on the difference between them. This will provide the most accurate estimation of source film grain.

Known Issues

• There have been reports that certain videos will fail to apply film grain properly. This is likely related to aomenc's --keyframe-filtering=2.