When encoding H264 on iOS, its contents doesn't seem to contain colorimetry information when decoded by GStreamer, resulting in following warnings: > 2:59:30.649107764 1 0x7f0298049400 WARN video-info video-info.c:204:validate_colorimetry: Need to specify a color matrix when using YUV format (I420) > 2:59:30.649125302 1 0x7f0298049400 WARN video-info video-info.c:520:gst_video_info_from_caps: invalid colorimetry, using default Those warnings are not present when VP8 is used, not present with desktop Safari and H264 (which makes me think it is related to hardware-accelerated encoder) and not present with Firefox/Chromium. Those are annoying warnings and would be nice to fix in iOS version of Safari.
Thanks Nazar, can you detail whether this is with high profile or baseline? Can you detail the impact of the issue?
This is baseline. The impact is primarily A HUGE amount of warnings in logs, visually there doesn't seem to be anything bad, I guess GStreamer's default works fine there.
It would help to understand what the spec says here. That will tell us whether encoder should be fixed, or decoder, or application using decoder output.
Decoding is done by libav integration in GStreamer, so application using it doesn't do anything special. And since it works fine with every other browser I tried so far except mobile Safari, I believe it is mobile Safari that needs to be tweaked here. But I'm not an expert in the field to suggest something more specific.
<rdar://problem/79357214>