On 30/01/2023 13:23, John Cox wrote: > Hi > > How should I check whether or not a given profile and level is > supported by a stateful decoder? Chrome uses VIDIOC_QUERYMENU to test > whether a given profile is supported by, say, > V4L2_CID_MPEG_VIDEO_H264_PROFILE. Is this "correct"? Certainly a few > decoders seem to support this usage (qcom/venus, mediatek and possibly > some others). > > The documentation currently suggests that > V4L2_CID_MPEG_VIDEO_H264_PROFILE is only an encoder control. Should > the documentation be extended to cover decoder use too? I think the documentation is out of date. For decoders this control definitely makes sense, but only as a READONLY control. After all you can't set it. Ideally it would also report which profile the currently decoding stream uses, but I don't know if that is always possible. Regards, Hans
