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Old 17th August 2015, 07:48   #30  |  Link
hello_hello
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Join Date: Mar 2011
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Quote:
Originally Posted by OvejaNegra View Post
i always assumed that was the main porpuse of colormatrix (because Xvid / MPEG4 dont have that info on the stream) even now with x264, there is the risk of decoders ignoring the info and work according to resolution.
Exactly, which is why it's a good idea to use rec.601 for SD and rec.709 for HD when encoding with Xvid, and convert the colors accordingly when downscaling/upscaling, because Xvid can't write the colorimetry info, so the playback device must assume a colorimetry based on resolution.
I still don't understand why that was best practice for years, but because x264 has the ability to write the colorimetry info, it's now a sin to follow the same rule.
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