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BloodyBaron
27th June 2004, 18:33
Hi,

As I'm using several video utilities discussed on the Doom9 forums, I have often came across the notion "YV12" and "YYUV" or something like this. It seems to refer to "color spaces".
Could anyone tell me a bit more about what are color spaces, what they are used for, and what (if there are some! ;) are the "best" color spaces to use when processing video, when the choice is given? :)

Thanks for your help. If I missed something while searching via the Search function, I apologise in advance :(

(and sorry if my English is approximative, I'm French! ;) )

killingspree
27th June 2004, 19:42
colorspace is the way the color information is stored in the video, going into the differences between RGB24, RGB32, YUV2, YV12 would be too much atm.

fact is that all DVD data is stored in YV12 format. fact also is, that converting between those colorspaces degardes the quality of the final output (although slightly) and slows down the process as it takes up CPU time!

anyway, therefore, it is best to stay in YV12 colorspace whenever possible, when ripping from DVDs. this is made possible by the combination of dvd2avi, avisynth and virtualdubmod and gordianknot aswell as autoGK automate this process!

hth
steVe

BloodyBaron
27th June 2004, 20:45
Thanks for your prompt reply! :)

BloodyBaron

ammck55
27th June 2004, 20:58
I see that Mr. Killingspree has given you some help on your request, but I'll go ahead and post this, along with a link to a YV12 colorspace explanation (http://www.avisynth.org/index.php?page=ColorSpaces) from the Avisynth forum. It does, indeed, get technical very quickly; some reading on colorspaces in general might be in order. Wikipedia also has some nice information on the topic, just google it up!

ammck55

BloodyBaron
29th June 2004, 18:50
@ammck55: Thanks for the link! :)

pernas
12th July 2004, 01:45
Originally posted by killingspree
colorspace is the way the color information is stored in the video, going into the differences between RGB24, RGB32, YUV2, YV12 would be too much atm.

fact is that all DVD data is stored in YV12 format. fact also is, that converting between those colorspaces degardes the quality of the final output (although slightly) and slows down the process as it takes up CPU time!

anyway, therefore, it is best to stay in YV12 colorspace whenever possible, when ripping from DVDs. this is made possible by the combination of dvd2avi, avisynth and virtualdubmod and gordianknot aswell as autoGK automate this process!

hth
steVe
Hopefully i'm not out on thin ice but in Doom9's guide @ http://www.doom9.org/index.html?/mpg/d2a-mpeg2dec.htm
it says "keeping the video data in the DVD-native YUV2 colorspace" - isn't that a bit misleading :(

Wilbert
12th July 2004, 12:54
I guess it's sort of a typo. There's no YUV2. Like people said it should be YV12 (actually I420).

RGB24, RGB32, YUV2, YV12 would be too much atm.
Killingspree meant YUY2, not YUV2.