[Bug]: Magenta line on top of H.265 video

[anonymix007]

Which component impacted?

Encode

Is it regression? Good in old configuration?

None

What happened?

First example is a GStreamer pipeline with https://github.com/games-on-whales/gst-wayland-display:

$ GST_PLUGIN_PATH=./target/debug/ GST_GL_PLATFORM=egl gst-launch-1.0 waylanddisplaysrc ! 'video/x-raw(memory:DMABuf),width=1920,height=1080,framerate=60/1' ! vapostproc ! vah265enc ! vah265dec ! glimagesink

Second example is just with videotestsrc:

$ GST_GL_PLATFORM=egl gst-launch-1.0 videotestsrc ! 'video/x-raw,width=2160,height=1080,framerate=60/1' ! vapostproc ! vah265enc ! h265parse ! vah265dec ! glimagesink

Resizing the window seems to fix the issue for the videotestsrc pipeline, but the waylanddisplaysrc one is broken no matter what.

Also, while resizing more lines briefly appear for a moment:

Using avdec_h265 and/or videoconvert ! gtksink changes nothing, also, vaav1enc and vah264enc are not affected.

What's the usage scenario when you are seeing the problem?

Game Streaming

What impacted?

No response

Debug Information

$ vainfo
Trying display: wayland
Trying display: x11
vainfo: VA-API version: 1.22 (libva 2.22.0)
vainfo: Driver version: Intel iHD driver for Intel(R) Gen Graphics - 25.3.4 ()
$ eglinfo
...
OpenGL core profile vendor: Intel
OpenGL core profile renderer: Mesa Intel(R) Arc(tm) B580 Graphics (BMG G21)
OpenGL core profile version: 4.6 (Core Profile) Mesa 25.3.5-arch1.1
...
$ lspci -nn |grep  -Ei 'VGA|DISPLAY'
03:00.0 VGA compatible controller [0300]: Intel Corporation Battlemage G21 [Arc B580] [8086:e20b]

vainfo.log

trace.tar.gz

Do you want to contribute a patch to fix the issue?

No.