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rapjp2001
22nd June 2003, 00:56
Hi All,

I have been experimenting with transferring my DV footage to DVD and hence my questions over the past few days...

Here is another issue I am having --

When I max out the bitrate (in VBR mode) to 8 Mbps, In my resultant MPEG2 file, I am seeing the bitrate at times spiking well over 8.8 Mbps...thereby making my overall muxed bitrate well over thee 9.8 MBps...This is causing some issues with playback on one of my DVD players (other players seem to be more forgiving!)..I get a sort of a beep whevever the bitrate is over the limit on this JVC player I have...

For the completist -- here is the scenario:
MPEG2 compressed with VBR, Q set to a 1 (I want the program to give better picture quality over compression) and Avg bitrate to 7 Mbps and max set to 8 Mbps. The audio is PCM, 48 Khz, 16 bit Stereo which PowerDVD in the final DVD image reports as 1536 kbps...

So, the math dictates that by over muxed bitrate should not exceed : 8000 (for video) + 1536 (for PCM audio) = 9546 kbps, which is below the max! However, as I stated about, sometimes the bitrate spikes over that mark and i get those beeps on my JVC player(which is perhaps a stickler for standards)...

What can I be doing wrong -- What I have done is obviusly reduce the max and avg. bitrate and I am fine, but I want to use the max 8000 bitrate if I can...

Help!

vwo
25th June 2003, 00:44
do you have "DVD Compliant" Box checked? I have had problems with this box - try unchecking it and running again. (I believe with the box checked, CCE does some sort of averaging of the bitrate throughout the movie, and it might cause parts to jump over the limit (it will keep the max bitrate below 9800, but since it is not taking into consideration the audio portion, it assumes that it can go to 9800 on the video)

rapjp2001
25th June 2003, 01:10
Yep! I have the DVD Compliant box checked...I will uncheck it...But will that not affect other aspects in the final MPEG and perhaps make it incompatible with DVD Video MPEG stream standards...I am asking as I do not know what the repercussions could be

vwo
25th June 2003, 01:12
nope - as long as you have the max bitrate (audio+video+subtitle+extras) under 9800 you will be ok