VMAF Support

VMAF - Video Multi-Method Assessment Fusion is a Netflix Open Source project for evaluating the quality of video files.

FFmpeg-Docker provides build instructions for VMAF by default, and exposes an API endpoint for processing files with VMAF and generating results.

Media files can be processes relative to the media directory and result exported to a MY-VMAF-TEST.json file.

Endpoints

• api/vmaf

Running a VMAF test

GET - api/vmaf/file

Request Body

{
    "input": {
        "filename": "test-file.mov"
    },
    "reference": {
        "filename": "reference-file.mov"
    },
    "output": "test-output.json",
    "model": "vmaf_v0.6.1.json"
}

Alternatively, running from the broswers

http://SERVER_IP:SERVER_PORT/api/vmaf/test?filename=test-file.mov&reference=reference-file.mov

Running the above command again after starting the test will display information about the task progress.

If you need to stop the current command running you can use the following command;

http://SERVER_IP:SERVER_PORT/api/vmaf/test?kill=true

Underlying Command

Sending the above API command results in the following underlying command being run on the server is;

ffmpeg -i test-file.mov -i reference-file.mov -y -lavfi libvmaf=model_path=/ffmpeg_sources/vmaf/model/vmaf_v0.6.1.json:log_fmt=json:psnr=1:ssim=1:ms_ssim=1:log_path=test-output.json -f null -

Generating Graphs from the outputs

In the example above the parameter output was set to test-output.json. This means that all of the results are saved in text to this file.

This can be directly downloaded as follows

• As a JSON object - http://SERVER_IP:SERVER_PORT/api/vmaf/results/json?filename=test-output.json
• As a CSV object - http://SERVER_IP:SERVER_PORT/api/vmaf/results/csv?filename=test-output.json
• As a JSON file - http://SERVER_IP:SERVER_PORT/api/vmaf/results/download/json?filename=test-output.json
• As a CSV file - http://SERVER_IP:SERVER_PORT/api/vmaf/results/download/csv?filename=test-output.json

A graph of the results can be generated here - http://SERVER_IP:SERVER_PORT/html/chart.html?filename=test-output.json using Chart.js.

Rememebr to change the filename query in the URL to the one set as the output parameter when running the test.

Docker Build

# Add source and compile for Netflix VMAF support
RUN git -C libvmaf pull 2> /dev/null || git clone --depth 1 https://github.com/Netflix/vmaf.git && \
    cd ./vmaf/libvmaf && \
    apt -y install ninja-build meson && \
    meson build --buildtype release && \
    ninja -vC build && \
    ninja -vC build install

Adding VMAF support to FFmpeg Build configuration

RUN ./configure \
        ...
        --enable-libvmaf