Quote:
Originally Posted by pie1394
The stream demuxer or the video decoder often knows the video output's color space. (Of course, only if appropriately encoded)
To make it more accurate to handle the decoded video frame's "color space", there are two methods:
1. If there is such MetaData embedded in the decoded video frame, the video post-processor / renderer can handle this by itself.
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True.
Quote:
Originally Posted by AJ73
I do not understand why YV12 (as a 4:2:0 color subsampling) is better in quality than YUY2 (or UYVY) that has twice as much color information from the original source than YV12 (or NV12).
Is generally more information from the source not better than less?
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Yes, but only if the source actually contains that much information. And that is exactly the key point. By far most sources do not contain more than 4:2:0.
Quote:
Originally Posted by AJ73
MPEG-4 and H.264 (not the studio and high quality profiles) use 4:2:0 internally so the information in the source (file, RTP stream) is already lost.
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It's not only MPEG4 and h264. MPEG1, MPEG2, MPEG4, h264, DviX, Xvid, VC-1 all usually use 4:2:0. There are some rare exceptions where 4:2:2 or 4:4:4 is encoded, but 4:2:0 is by far the most common used format for encoding. Still, many decoders insist on outputting YUY2, if you let them, even for 4:2:0 sources. Which means that the decoder is internally doing chroma upsampling in inferior quality. And that is what I want to avoid.
Edit: Seems I was too slow in replying...
