AVI to WebM via CLI

AVI to VP9 + Opus using the same profile as MP4 → WebM.

Packages to install

ffmpeg is enough. The codecs are the same: libvpx-vp9 and libopus.

ffmpeg

sudo apt-get update
sudo apt-get install -y ffmpeg

How to run the command

ffmpeg -i input.avi -c:v libvpx-vp9 -crf 32 -b:v 0 -deadline good -cpu-used 4 -c:a libopus -b:a 96k output.webm.

ffmpeg -y -i input.avi -c:v libvpx-vp9 -crf 32 -b:v 0 -deadline good -cpu-used 4 -c:a libopus -b:a 96k output.webm

Dockerfile example

Build a minimal Ubuntu image with the required packages and run the conversion inside the container.

FROM ubuntu:24.04

RUN apt-get update && \
    apt-get install -y --no-install-recommends \
        ffmpeg && \
    rm -rf /var/lib/apt/lists/*

WORKDIR /work

docker build -t avi-to-webm .
docker run --rm -v "$PWD:/work" -w /work avi-to-webm \
  ffmpeg -y -i input.avi -c:v libvpx-vp9 -crf 32 -b:v 0 -deadline good -cpu-used 4 -c:a libopus -b:a 96k output.webm

Example commands

Run these locally after installing the packages, or inside the container from the Dockerfile.

ffmpeg -y -i input.avi -c:v libvpx-vp9 -crf 32 -b:v 0 -deadline good -cpu-used 4 -c:a libopus -b:a 96k output.webm

ffmpeg -y -i input.avi -c:v libvpx-vp9 -crf 36 -b:v 0 -c:a libopus -b:a 64k output.webm