Talk:OggYUV

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=== Interlace Flag? ===
=== Interlace Flag? ===
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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)
+
* 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)
-
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)
+
* 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)
=== Variable frame-rates ===
=== 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.
+
* There doesn't seem to be any handling of variable frame-rate data, or a specification for a timebase for the granulepos.
--[[User:Gumboot|Gumboot]] 03:00, 9 Nov 2005 (PST)
--[[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)
+
* 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)
=== Codec Identifier ===
=== 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)
+
* 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)
-
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)
+
* 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)
=== Aspect ratio ===
=== Aspect ratio ===
-
Is the aspect ratio the pixel aspect or the frame aspect? --[[User:Gumboot|Gumboot]] 03:00, 9 Nov 2005 (PST)
+
* Is the aspect ratio the pixel aspect or the frame aspect?  
 +
--[[User:Gumboot|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.  --[[User:Arc|Arc]] 10:42, 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.   
 +
--[[User:Arc|Arc]] 10:42, 9 Nov 2005 (PST)

Revision as of 21:17, 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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