Build Failures With Bad AV1 Dependencies (Old `libav`)

[mohammad-matini]

Description

Building ALVR dependencies with AV1 support fails with cryptic error:

WARNING: Disabled av1_vaapi_encoder because not all dependencies are satisfied: VAEncPictureParameterBufferAV1

VAEncPictureParameterBufferAV1 is part of libav. On Slackware 15 we have libav 2.13.0, which does not have that symbol, causing ffmpeg to throw warnings, aborting the build. Building and installing 2.21.0 fixed the issue, allowing ffmpeg to build, and then ALVR. ALVR runs normally afterwards.

Of course upgrading libav to a newer version is risky, only do it if you know what you're doing.

Otherwise, a work-around is: disabling AV1 by deleting:

alvr/xtask/patches/0001-av1-encode-backport.patch

and modifying alvr/xtask/src/dependencies.rs to remove the two lines:

--- a/alvr/xtask/src/dependencies.rs
+++ b/alvr/xtask/src/dependencies.rs
@@ -166,10 +166,8 @@ pub fn build_ffmpeg_linux(nvenc_flag: bool, deps_path: &Path) {
         "--disable-everything",
         "--enable-encoder=h264_vaapi",
         "--enable-encoder=hevc_vaapi",
-        "--enable-encoder=av1_vaapi",
         "--enable-hwaccel=h264_vaapi",
         "--enable-hwaccel=hevc_vaapi",
-        "--enable-hwaccel=av1_vaapi",
         "--enable-filter=scale_vaapi",
         "--enable-vulkan",
         "--enable-libdrm",

This work-around worked for me normally for weeks. Using x264 as encoder.

Environment

Hardware

Irrelevant.

Installation

ALVR Version: v20.8.1

Install Type: From Source

OS Name and Version: GNU/Linux (Slackware 15)

[mohammad-matini]

I don't think there's much to do here on ALVR's side; the error is hard to decipher, but it is from ffmpeg's configure script. This can probably be closed for now I think. I filed this issue for anyone from the future who would have felt the pain of having zero search results for that error, now there would be one.

[mohammad-matini]

I don't think I have AV1 hardware support, switching to AV1 in ALVR results in crashes or black screens on the headset. The fix mentioned above is just to compile ALVR to use it with x264.

GPU stuff:

Mesa Gallium driver 23.1.3 for AMD Radeon Graphics (renoir, LLVM 13.0.0, DRM 3.42, 5.15.94)

VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Cezanne [Radeon Vega Series / Radeon Vega Mobile Series] (rev c9)

[Vixea]

Yea there's nothing we're going to do to fix this either the distro updates it's libav or building on it isn't supported otherwise you can use the portable tar file.