Problem - DVDA - Subtitles

Cunhambebe wrote on 6/9/2005, 7:28 PM
I've never had a problem with DVDA and subs, but now, I do have one. I frameserved my project from Vegas to TMPGEnc, encoding at VBR 8500 to 9500. I used this MPEG2 file to author my DVD as a test. I have 3 subtitles, French, English and Portuguese, video is about 3 minutes, sound is AC-3 5.1. In fact, I've prepared and burned the DVD 2 times and the problem is the same: subs are disappearing too often. I thought about 2 possibilities:
1. the bitrate may be upsetting the player;
2.the size of this project which is too small (I think the problem might be caused by the first statement).
What do I do?
Thanks in advance.

Comments

johnmeyer wrote on 6/9/2005, 10:01 PM
the bitrate may be upsetting the player;

Subtitles are part of the total bitrate limitation. Also, I just ran into a terrible set of problems which were eventually traced to using MPEG-2 that was created in an application other than Vegas. The results of doing this was that some (not all) players would freeze or pause at chapter points, even though it was one continuous MPEG-2 file. Therefore, I'd try two things:

1. Encode in Vegas, not TMPGEnc.
2. Lower the MAX bitrate down to below 9000, and take the average bitrate down to at least 8200.
Cunhambebe wrote on 6/10/2005, 8:33 AM
Thanks a lot, john. It's always great hearing from you. Yes, you're absolutely right! The problem was the bitrate; here's what I did to fix the problem...

I've just decreased the bitrate to VBR 9000 to 8000. The thing is, despite the fact the bitrate was within spec, as you noticed, I was encoding only the video stream. That means there are other things such as the Sountrack AC-3 and the subtitles. The video was playing prefectly; in fact, I was having some problem with the subtitles exactly in a section of the video where it showed some visual effects (where probably the compressor used a higher bitrate). I've supposed the problem (subs were disappearing) was caused by the increase of the bitrate in that section + AC-3 and + subs, what could raise the final bitrate too far from the limit. Same thing happens with Xvid movies. Some people like to encode their own videos to Xvid (which is the greatest codec nowadays ;) and they too often pay attention to the bitrate when they are encoding the video stream since subs and soundtrack will be multiplexed later, increasing the final bitrate/size what could easily upset compatible DVD players. BTW, hope you don't mind, but I like TMPGEnc much better than Vegas' MC built-in. It's just that I guess MC blurs the final result in a certain way (but anyway, it sure is a great encoder - "sometimes" when I encode my own targa sequences to MPEG2, which were previously rendered in Lightwave, Vegas' MC has shown a better result than TMPEGnc). Hope this helps other users who have the same problem. Thanks again for your help.
Cunhambebe wrote on 6/10/2005, 11:53 AM
One more thing, John: why did you tell me to encode the average bitrate to at least 8200? I guess 8000 was good enough despite the fact I could spot some dots here and there showing what the compressor had done to the video. I re-encoded the project again to MPEG2 at an average bitrate of 8500 to 9000. It worked, but the result looks the same as the previous one (8000 to 9000) and the file is a little bigger (In fact, 10 MB bigger). What file should I keep? Should I burn the DVD with the first one (8000) or the second one (8500)?
Thanks
:)