Talk:OggYUV

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* The interlacing information doesn't seem complete to me.  How do you know which field(s) you have in any give packet, for example?  How do you distinguish between a 25Hz shutter and a 50Hz shutter?  Field order switching?  Mixing with uninterlaced data?
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=== Interlace Flag? ===
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* There doesn't seem to be any handling of variable frame-rate data, or a specification for a timebase for the granulepos.
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The interlacing information doesn't seem complete to me.  How do you know which field(s) you have in any give packet, for example?  How do you distinguish between a 25Hz shutter and a 50Hz shutter?  Field order switching?  Mixing with uninterlaced data? --[[User:Gumboot|Gumboot]] 03:00, 9 Nov 2005 (PST)
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* The identifier seems a little short.  You'd get false positives if somebody wanted to use a "YUVx" format, for example.
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* Is the aspect ratio the pixel aspect or the frame aspect? --[[User:Gumboot|Gumboot]] 03:00, 9 Nov 2005 (PST)
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In my experience, all interlace is every other frame, even scanlines followed by odd scanlines.  Is there any video codec which supports more than an interlace flag? --[[User:Arc|Arc]] 10:42, 9 Nov 2005 (PST)
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=== Variable frame-rates ===
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There doesn't seem to be any handling of variable frame-rate data, or a specification for a timebase for the granulepos.
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--[[User:Gumboot|Gumboot]] 03:00, 9 Nov 2005 (PST)
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Granulepos is the last frame decodable in the current packet/page.  As far as variable framerates within a single stream, is there any codec which supports this currently? --[[User:Arc|Arc]] 10:42, 9 Nov 2005 (PST)
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=== Codec Identifier ===
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The identifier seems a little short.  You'd get false positives if somebody wanted to use a "YUVx" format, for example. --[[User:Gumboot|Gumboot]] 03:00, 9 Nov 2005 (PST)
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I believe that's OK with raw formats, if someone wanted to use a YUV-like codec they could use a prefix, vs a suffix, to identify it by.  Also, if their header packet ID is something other than 0x00, it will not generate a false positive to have a YUV* codec identifier since the YUV plugins only support streams which begin with packet id 0. --[[User:Arc|Arc]] 10:42, 9 Nov 2005 (PST)
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=== Aspect ratio ===
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Is the aspect ratio the pixel aspect or the frame aspect? --[[User:Gumboot|Gumboot]] 03:00, 9 Nov 2005 (PST)
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Frame aspect, this acts exactly like the aspect ratio in the Theora header, right down to having the same bit-size for the fields. Typically, the ratio is 4:3 or 16:9.  --[[User:Arc|Arc]] 10:42, 9 Nov 2005 (PST)

Revision as of 18:42, 9 November 2005

Contents

Interlace Flag?

The interlacing information doesn't seem complete to me. How do you know which field(s) you have in any give packet, for example? How do you distinguish between a 25Hz shutter and a 50Hz shutter? Field order switching? Mixing with uninterlaced data? --Gumboot 03:00, 9 Nov 2005 (PST)

In my experience, all interlace is every other frame, even scanlines followed by odd scanlines. Is there any video codec which supports more than an interlace flag? --Arc 10:42, 9 Nov 2005 (PST)


Variable frame-rates

There doesn't seem to be any handling of variable frame-rate data, or a specification for a timebase for the granulepos. --Gumboot 03:00, 9 Nov 2005 (PST)

Granulepos is the last frame decodable in the current packet/page. As far as variable framerates within a single stream, is there any codec which supports this currently? --Arc 10:42, 9 Nov 2005 (PST)


Codec Identifier

The identifier seems a little short. You'd get false positives if somebody wanted to use a "YUVx" format, for example. --Gumboot 03:00, 9 Nov 2005 (PST)

I believe that's OK with raw formats, if someone wanted to use a YUV-like codec they could use a prefix, vs a suffix, to identify it by. Also, if their header packet ID is something other than 0x00, it will not generate a false positive to have a YUV* codec identifier since the YUV plugins only support streams which begin with packet id 0. --Arc 10:42, 9 Nov 2005 (PST)


Aspect ratio

Is the aspect ratio the pixel aspect or the frame aspect? --Gumboot 03:00, 9 Nov 2005 (PST)

Frame aspect, this acts exactly like the aspect ratio in the Theora header, right down to having the same bit-size for the fields. Typically, the ratio is 4:3 or 16:9. --Arc 10:42, 9 Nov 2005 (PST)

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