ffmpeg support for v2.0 API and Homebrew

[slhck]

I see that FFmpeg does not support the v2.0 API yet. Are there plans to add support for it, perhaps in a backwards-compatible manner? (That is, switching to the old API if libvmaf is <2.0.)

Only if FFmpeg supports it, libvmaf can be bumped in Homebrew. If there's no support, bumping in Homebrew will mean that compiling ffmpeg with --enable-libvmaf will fail, which would break custom builds.

So IMO the steps would be:

• Add support for libvmaf 2.0 in FFmpeg
• Wait for stable FFmpeg release
• Bump FFmpeg in Homebrew
• Bump libvmaf in Homebrew
  • Fix the applied patch

[kylophone]

The current libvmaf ffmpeg works as-is still since the old api call compute_vmaf() Is still supported. That being said, I will be working on an updated filter this week to take advantage of v2.0.0 which I will be sending to ffmpeg-devel. When that is in-progress/done, I will provide updates via this issue.

Packaging libvmaf now should hopefully be a lot less painful now. We are not providing default model files as part of the installation anymore, since built-in models are available. This should solve problems like this: #324 (comment).

[slhck]

Thanks for the heads-up! I didn't see that there was support for the old API call. That means we can safely update libvmaf on Homebrew though. I'll check out the failing PR later.

Packaging libvmaf now should hopefully be a lot less painful now

Yeah, I saw that – very nice! Good that the models are JSON now, too.

[vans163]

To add to this, it seems VMAF changed the build system around and I cannot seem to build a version of FFMPEG with VMAF statically compiled, it keeps trying to load the libvmaf.so.1 when ffmpeg or ffprobe run now. I even tried the new instructions to build the static lib and indeed i get the static lib and shared built, but FFMPEG keeps trying to want the dynamic one.

(this is a build for podman)

RUN cd ~/ffmpeg_sources && \
    wget -q https://github.com/Netflix/vmaf/archive/v2.0.0.zip -O vmaf-2.0.0.zip && \
    unzip -qq vmaf-2.0.0.zip && cd vmaf-2.0.0 && \
    export PATH="$HOME/ffmpeg_bin:$PATH" && \
    cd libvmaf && \
    meson setup --default-library=static --buildtype=release --prefix="/root/ffmpeg_bin" --libdir=lib build && \
    ninja -vC build && \
    cp build/src/libvmaf.* /root/ffmpeg_build/lib/

[1480c1]

you might want to try to brute force it then and delete the shared library

[slhck]

This is a bit unrelated to this issue though. Could you open a separate issue please?

[gdavila]

When ffmpeg already support v2.0 API, Will “No Enhancement Gain” mode be available through ffmpeg?

[slhck]

@gdavila The NEG variant is a model like the others and can be selected freely.

[luigi311]

@kylophone
Any update on the new ffmpeg patch to use vmaf 2.0 apis and use the builtin model by default?

[pdaga2]

Any further update on this?

[slhck]

This all seems to work now. I am using FFmpeg 5.1 with libvmaf 2.3.1 and I can use all the new model options and features.