mtk-vpu: "No matching render target supported by device."

[leo60228]

I'm trying to use this backend on a Mediatek tablet (Lenovo IdeaPad Duet/krane, MT8183). vainfo works fine:

[nix-shell:~]$ vainfo
Trying display: wayland
libva info: VA-API version 1.22.0
libva info: User environment variable requested driver 'v4l2'
libva info: Trying to open /nix/store/i111fc276l9frns0mi8kk95kf8c4i6w8-libva-v4l2-unstable-2024-10-20/lib/dri/v4l2_drv_video.so
libva info: Found init function __vaDriverInit_1_22
libva info: va_openDriver() returns 0
vainfo: VA-API version: 1.22 (libva 2.22.0)
vainfo: Driver version: v4l2
vainfo: Supported profile and entrypoints
      VAProfileH264Main               : VAEntrypointVLD
      VAProfileH264High               : VAEntrypointVLD
      VAProfileH264ConstrainedBaseline: VAEntrypointVLD
      VAProfileH264MultiviewHigh      : VAEntrypointVLD
      VAProfileH264StereoHigh         : VAEntrypointVLD

However, whenever I try to actually decode a video, I get a "No matching render target supported by device." error.

[mxsrc]

Can you share the output of v4l2-ctl -d $device --list-formats?

[leo60228]

$ v4l2-ctl -d /dev/video2 --list-formats
ioctl: VIDIOC_ENUM_FMT
        Type: Video Capture Multiplanar

        [0]: 'MM21' (Mediatek 8-bit Block Format)

[mxsrc]

Okay, the driver only offers one capture format which seemingly requires a color space conversion in the translation layer. This is something we dont do yet, so adding it without access to the Hardware does not seem feasible.

Also Im afraid at the moment I cant invest a lot of time on this since I just started a new job. Ill try and see anyway, whether there is a cheap option available that uses the same driver.

[leo60228]

For what it's worth, I personally decided to just throw money at this problem and buy a tablet without a Mediatek SoC. I'd still appreciate being able to use the tablet I already have, of course, but I don't think it's worth buying hardware just to fix this issue.

…

On Sun, May 4, 2025, 2:16 PM Max Schettler ***@***.***> wrote: *mxsrc* left a comment (mxsrc/libva-v4l2#6) <#6 (comment)> Okay, the driver only offers one capture format which seemingly requires a color space conversion in the translation layer. This is something we dont do yet, so adding it without access to the Hardware does not seem feasible. Also Im afraid at the moment I cant invest a lot of time on this since I just started a new job. Ill try and see anyway, whether there is a cheap option available that uses the same driver. — Reply to this email directly, view it on GitHub <#6 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AB7X32PC2DPB7PSVLCG3MBL24ZKP5AVCNFSM6AAAAAB3R22JD6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQNBZGM2DONRZGQ> . You are receiving this because you authored the thread.Message ID: ***@***.***>