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FiW
20th July 2002, 11:55
what calculate .avi overhead? and... overhead for ac3 sound (depending on delays in ms)? and...

if movie 200000frames, 23,976fps, ac3 448kbps - i calculate ac3 size in KBytes - 448 * 1000 / 8 * 200000 / 23,976 / 1024 = 456185. why GKnot tell me - 456203 Kbytes?

if movie 200000frames, 25fps, ac3 448kbps - i calculate ac3 size in KBytes - 448 * 1000 / 8 * 200000 / 25 / 1024 = 437500. GKnot tell me - 437500 Kbytes. :D

if movie 123456frames, 25fps, ac3 448kbps - i calculate ac3 size in KBytes - 448 * 1000 / 8 * 123456 / 25 / 1024 = 270060. why GKnot tell me - 270047 Kbytes?

* edit
in xvid src i found it

// compensate for avi frame overhead
desired -= frames * 24;

new question

frames: 123456 / fps: 23,976 / interleave: 96ms / ac3: 256kbps / 1cd

sizes:
audio: 256 * 1000 / 8 * 123456 / 23,976 = 164772773 bytes
audio-oh: 24 * 123456 / 23,976 * 1000 / 96 = 1287287 bytes
video-oh: 24 * 123456 = 2962944 bytes
video: 734003200 - 164772773 - 1287287 - 2962944 = 564980196 bytes

so it is correct?