2nd try for a keyframe definition

based on richs comment


git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@20647 b3059339-0415-0410-9bf9-f77b7e298cf2
This commit is contained in:
michael 2006-11-03 21:13:50 +00:00
parent e79daa507c
commit 8a881c1e55
1 changed files with 9 additions and 5 deletions

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@ -42,11 +42,15 @@ MUST the specific part must be done to conform to this standard
SHOULD it is recommended to be done that way, but not strictly required
keyframe
a frame which can be decoded correctly on its own (=without using
information from any other frames)
if no such frames exist in a codec (for example due to use of overlapped
transforms like the MDCT in an audio codec) then a keyframe shall be any
frame from which onward all frames can be decoded correctly
The nth frame is a keyframe if and only if frames n, n+1, ... in
presentation order (that are all frames with a pts >= frame[n].pts) can
be decoded successfully without reference to frames prior n in storeage
order (that are all frames with a dts < frame[n].dts)
if no such frames exist (for example due to use of overlapped transforms
like the MDCT in an audio codec) then the definition shall be extended
by droping n out of the set of frames which must be decodable, if this
is still insufficient then n+1 shall be droped, and so on until there is
a keyframe
(FIXME maybe move somewhere else?)