[NUT-devel] max pts/distance stuff

[Michael Niedermayer]

Hi

currenbtly we have
"
max_distance
    max distance of syncpoints, the distance may only be larger if
    there is no more than a single frame between the two syncpoints. This can
    be used by the demuxer to detect damaged frame headers if the damage
    results in too long of a chain

    syncpoints SHOULD be placed immediately before a keyframe if the
    previous frame of the same stream was a non-keyframe, unless such
    non-keyframe - keyframe transitions are very frequent

    SHOULD be set to <=32768
    if the stored value is >65536 then max_distance MUST be set to 65536

max_pts_distance
    max absoloute difference of pts of new frame from last_pts in the
    timebase of the stream, without a checksum after the frameheader
    Note that last_pts is not necessarily the pts of the last frame
    on the same stream, as it is altered by syncpoint timestamps.

max_frame_size
    max frame size without a checksum after the frameheader.
    MUST be <=4*max_distance. If stored value is bigger then
    max_frame_size MUST be set to 4*max_distance 
"

in the spec, 

there are several issues which need disscussion
1. no limit for max_pts_distance, users could set it to insane values and
   cause troubble on the demuxer side, yes theres the time rescaling issue
2. max_frame_size limit is too large, its practically 256k, i think 64k or
   less is more reasonable
3. what about droping one varaible and max_distance=max_frame_size?


-- 
Michael