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waka · 18th June 2003, 17:39

For me, the issue does seem to be caused by colorspace conversions performed by the codec. Everything is fine with zero or two(letting the codec fix itself) conversions. With one conversion, either encoded RGB/decoded YUV or encoded YUV/decoded RGB, there are problems.

Using blankclip(color=$0000f0,pixel_type="yuy2"), starting clip has YUV values of 39, 234, 111. Picvideo mjpeg encoded with fast recompress for YUV or full processing for RGB. Resulting mjpeg opened with avisynth using pixel_type="yuy2" or "rgb32". Values checked with coloryuv(analyze=true), converttoyuy2() as necessary. Last two used coloryuv(levels="tv->pc") or "pc->tv" for correction.

Code:

EncodeYUV/DecodeYUV   Y:39 U:234 V:111
EncodeRGB/DecodeRGB   Y:39 U:234 V:111
EncodeYUV/DecodeRGB   Y:50 U:221 V:113
EncodeRGB/DecodeYUV   Y:27 U:248 V:108
EncYUV/DecRGB tv->pc  Y:40 U:234 V:111
EncRGB/DecYUV pc->tv  Y:39 U:233 V:111

I think sh0dan and myself are more or less describing the same thing. I hope I didn't give him the wrong idea in a previous discussion. I could also be totally wrong.

18th June 2003, 17:39	#7 \| Link
waka Registered User Join Date: Jul 2002 Posts: 29	For me, the issue does seem to be caused by colorspace conversions performed by the codec. Everything is fine with zero or two(letting the codec fix itself) conversions. With one conversion, either encoded RGB/decoded YUV or encoded YUV/decoded RGB, there are problems. Using blankclip(color=$0000f0,pixel_type="yuy2"), starting clip has YUV values of 39, 234, 111. Picvideo mjpeg encoded with fast recompress for YUV or full processing for RGB. Resulting mjpeg opened with avisynth using pixel_type="yuy2" or "rgb32". Values checked with coloryuv(analyze=true), converttoyuy2() as necessary. Last two used coloryuv(levels="tv->pc") or "pc->tv" for correction. Code: EncodeYUV/DecodeYUV Y:39 U:234 V:111 EncodeRGB/DecodeRGB Y:39 U:234 V:111 EncodeYUV/DecodeRGB Y:50 U:221 V:113 EncodeRGB/DecodeYUV Y:27 U:248 V:108 EncYUV/DecRGB tv->pc Y:40 U:234 V:111 EncRGB/DecYUV pc->tv Y:39 U:233 V:111 I think sh0dan and myself are more or less describing the same thing. I hope I didn't give him the wrong idea in a previous discussion. I could also be totally wrong.