Karovaldas
28th November 2003, 06:52
I've been getting this problemwith various scenarios:
a. encode a MPEG-2 stream with CCE 2.5 at 23.976FPS
b. do a 2:3 pulldown via pulldown.exe
c. the outcome, pulled-down (29.97FPS) file is from 1 to 5 seconds shorter
In both scenarios, I am converting DivX5 original video streams from PAL (25FPS) to NTSC (23.976). But I did the conversion in two different ways.
1. I used ChangeFPS(23.976) command in AviSynth 2.53 and fed the stream to CCE 2.5. Resulting file was the same length as the original. The stream was 1:34 and some change. When I subjected this stream to pulldown, the outcome was 5 seconds shorter. I muxed the audio (extracted via BeSweet) and the video (5 sec difference between the lengths of audio and pulled-down video) by using bbMPEG, and got an acceptable result with audio out of synch, but no change in synch as the movie goes on.
2. I used AssumeFPS(23.976) and this time the video got longer by just over 2 seconds per minute of the original material. Expected, as I changed the # of frames per second. But, again, after I pulled down the 23.976 stream to make it NTSC DVD standard 29.97 FPS, four different videos (30 to 50 minutes in length) shrunk from 1 to 5 seconds. The shrinking is NOT proportional to the length of the original--meaning longer, when pulled down, movies did not result in greater differences between the original and the pulled down version. I would have expected that if there was something systematic going on.
Anybody! What's going on? How do I fix this!
First, I though it was the problem with using ChangeFPS command since that produces some irregular frames. AssumeFPS, however, should keep all the frames intact and the pulldown should be done on full frames, so why does the length of the stream change?
a. encode a MPEG-2 stream with CCE 2.5 at 23.976FPS
b. do a 2:3 pulldown via pulldown.exe
c. the outcome, pulled-down (29.97FPS) file is from 1 to 5 seconds shorter
In both scenarios, I am converting DivX5 original video streams from PAL (25FPS) to NTSC (23.976). But I did the conversion in two different ways.
1. I used ChangeFPS(23.976) command in AviSynth 2.53 and fed the stream to CCE 2.5. Resulting file was the same length as the original. The stream was 1:34 and some change. When I subjected this stream to pulldown, the outcome was 5 seconds shorter. I muxed the audio (extracted via BeSweet) and the video (5 sec difference between the lengths of audio and pulled-down video) by using bbMPEG, and got an acceptable result with audio out of synch, but no change in synch as the movie goes on.
2. I used AssumeFPS(23.976) and this time the video got longer by just over 2 seconds per minute of the original material. Expected, as I changed the # of frames per second. But, again, after I pulled down the 23.976 stream to make it NTSC DVD standard 29.97 FPS, four different videos (30 to 50 minutes in length) shrunk from 1 to 5 seconds. The shrinking is NOT proportional to the length of the original--meaning longer, when pulled down, movies did not result in greater differences between the original and the pulled down version. I would have expected that if there was something systematic going on.
Anybody! What's going on? How do I fix this!
First, I though it was the problem with using ChangeFPS command since that produces some irregular frames. AssumeFPS, however, should keep all the frames intact and the pulldown should be done on full frames, so why does the length of the stream change?