rff-filter

Video frame filters for remade_ffmpeg_rs — FFmpeg's libavfilter, scoped to the graph shapes the CLI actually exposes: a linear -vf chain and an overlay composite for -filter_complex.

• FilterChain::parse — parses FFmpeg's -vf syntax (scale=320:240,crop=w:h:x:y) into a chain you can apply to each decoded VideoFrame.
• scale and crop filters today; the Filter trait is the extension point for more.
• output_dims — resolve the post-chain frame size without decoding anything, which is what the encoder needs at open time.
• overlay — composite one frame over another at (x, y), backing -filter_complex overlay.
• Empty spec = pass-through, so callers don't special-case "no filters".

Usage

use rff_filter::FilterChain;
use rff_core::{Error, PixelFormat, VideoFrame};

fn main() -> Result<(), Error> {
    // Exactly the string `ffmpeg -vf` takes.
    let mut chain = FilterChain::parse("scale=320:240,crop=160:120:80:60")?;

    // Resolve the output size before opening the encoder.
    let (w, h) = chain.output_dims(1920, 1080);
    println!("encoder should be opened at {w}x{h}");

    let frame = VideoFrame {
        width: 1920,
        height: 1080,
        format: PixelFormat::Yuv420p,
        planes: vec![vec![0u8; 1920 * 1080], vec![0u8; 960 * 540], vec![0u8; 960 * 540]],
        strides: vec![1920, 960, 960],
        pts: Some(0),
    };
    let _filtered = chain.apply(frame)?;
    Ok(())
}

Part of Remade With Rust

This crate is one layer of remade_ffmpeg_rs — a ground-up, permissively-licensed Rust rebuild of FFmpeg: a drop-in ffmpeg/ffprobe CLI on pure-Rust codecs, with no copyleft. Most users want the rff engine facade or the rff-cli binaries rather than this crate directly.

Also check out our sister project FFAI — media for an AI-first world — and the rest of github.com/remade-with-rust, including the standalone codec crates rusty_h264, rusty_vp9, rusty_mp3, rusty_aac, rusty-opus, rusty_vorbis, and the rusty-av1-toolkit forks.

About Mata Network

Mata Network builds sovereign, self-hostable infrastructure. Remade With Rust is our open-source home for the permissively-licensed building blocks that work depends on.

License

Apache-2.0. See the workspace LICENSE.