Talk:OggRGB: Difference between revisions

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=== Do we need a gamma correction field? ===
=== Do we need a gamma correction field? ===


=== YUV+RGB? ===
* How about specifying the color space (ie sRGB) -- And why not merging OggRGB and OggYUV and adding an additional color space identifier ? There's only one raw codec for audio althoug it may come in different flavours as well (float/integer samples, channel count, sampling rate) -- Sebi
* It's not purely an issue of colorspace, YUV does many things RGB does not do - most specifically chroma subsampling, which RGB doesn't worry about.  It's different from PCM - PCM is a format of samples, no matter what format those samples are in.  The RGB vs YUV issue is, by contrast, the difference between delta encoded audio and plain samples encoding.  Additionally, there's OggStream processing methods which are complicating this issue, I'll explain more with time.


=== Is there ever a case where RGB video has non-square pixels, ie, do we need an aspect ratio? ===
=== Is there ever a case where RGB video has non-square pixels, ie, do we need an aspect ratio? ===


Sebi: Storing that won't hurt. I'd do so. (Recall DVD resolutions, 720x480 (NTSC) or 720x576 is supposed to be DAR 4:3 or 16:9 (DAR = display aspect ratio))


=== How about support for skipped frames or variable duration? ===
=== How about support for skipped frames or variable duration? ===

Latest revision as of 01:20, 13 November 2005

Do we need a gamma correction field?

YUV+RGB?

  • How about specifying the color space (ie sRGB) -- And why not merging OggRGB and OggYUV and adding an additional color space identifier ? There's only one raw codec for audio althoug it may come in different flavours as well (float/integer samples, channel count, sampling rate) -- Sebi
  • It's not purely an issue of colorspace, YUV does many things RGB does not do - most specifically chroma subsampling, which RGB doesn't worry about. It's different from PCM - PCM is a format of samples, no matter what format those samples are in. The RGB vs YUV issue is, by contrast, the difference between delta encoded audio and plain samples encoding. Additionally, there's OggStream processing methods which are complicating this issue, I'll explain more with time.

Is there ever a case where RGB video has non-square pixels, ie, do we need an aspect ratio?

Sebi: Storing that won't hurt. I'd do so. (Recall DVD resolutions, 720x480 (NTSC) or 720x576 is supposed to be DAR 4:3 or 16:9 (DAR = display aspect ratio))

How about support for skipped frames or variable duration?

Is there a need for a VorbisComment -like header?