Scenarist problem (bitrate too high when it's obviously not?)

[clafferty]

I will try to explain this problem as best as I am able.

I am attempting to burn 8 episodes of a television show to disk. All eight were originally encoded in DivX 4.

I converted all the files to M2V using the same settings in TMPGenc. Constant bitrate of 1500, 352x240.

All of the files are accepted by Scenarist initially, and all play fine. When i go to make the disk, however, i get this error for three of the files.


Info Multiplexing VOB Main Stream
Error Video or Audio Buffer underflow: (Dts: 91178319, SCR 91178337)
Error dvd_mux : DoMux Multiplexing Error
Error Terminated Multiplexing (firefly.scn-Firefly.S01E03-t_t.vob).
Error Total bitrate is too HIGH. Please reduce the stream bitrate or the number of stream.
Error Multiplex is failed.

I have seen this error mentioned before in the forums, but the problem was always that the bitrate was set too high. Mine is set to 1500 with a normal audio track (same size as all the others). I cannot be crossing the 9.8 threshold, at least unless something is really really wrong.

With that in mind, I scanned the file with Bitrate Viewer. The peak is 1600.

I fixed the problem with one of the three files. I re-encoded them in DivX 5, then TMPGEnc'd them back to mpeg2. One of the files was accepted by Scenarist... the other two were not.

I hope someone has seen this problem and can advise me... because I keep running into it. I can supply any further information you ask for... Thanks in advance!

[clafferty]

i think i've narrowed down this problem -- but still need assistance.

it appears that it's not a case of the bitrate being too high... but being too low. if i encode the file at 8000kbps, it works. but i can't have the file that large... so what do i do? other files have worked at 1500 i've decided on... even lower at 1200. i've tried encoding at VBS with a 1500 minimum, 1800 max, 1500 avg... but that didn't help.

any suggestions?

[clafferty]

here's the error it just gave me, if it helps... i know nothing about GOP.


Info Multiplexing VOB Main Stream
Warning Total bitrate too HIGH. Video buffer overflow (DTS=28260 SCR=438 (around 00:00:00:00).

Info picture_type: IPBBPBBPBBPBBPBB

Info picture_size: 2010 138 138 2534 8341 8342 8342 8341 8342 8342 8341 8342 8342 8341 8342 138

Info gop bitrate: 1450740

Error dvd_mux : DoMux Multiplexing Error
Error Terminated Multiplexing (buffy6.scn-Buffy_6x16_Hells bellsRED_13_t.vob).
Error Total bitrate is too HIGH. Please reduce the stream bitrate or the number of stream.
Error Multiplex is failed.

[auenf]

Originally posted by clafferty
Info picture_type: IPBBPBBPBBPBBPBB


for NTSC, the GOP size is limited to 15 frames
for PAL, the GOP size is limited to 12 frames

the GOP you have there is 16 frames.

also, since you are encoding to 352x240 (NTSC 1/4 D1), you really should use MPEG-1 rather than MPEG-2, but dont choose a VCD template, cause it has a GOP size too big ;)

Enf...

[clafferty]

thanks for the info... but i need more. :)

i only got that gop error once, so i must have done something weird there... i am using the DVD (low resolution) setting in TMPGEnc... and it does not give an option to change to MPEG1 or modify the gop... i've tried using LSXMPEG with the same results. here is the error i am getting consistently.


Starting Multiplex Buffy_6x14_older_and_far__2 (1 / 1)
Info Multiplexing VOB Main Stream
Error Video or Audio Buffer underflow: (Dts: 520752, SCR 520770)
Error dvd_mux : DoMux Multiplexing Error
Error Terminated Multiplexing (buffy7.scn-Buffy_6x14_older_and_far__2_t.vob).
Error Total bitrate is too HIGH. Please reduce the stream bitrate or the number of stream.
Error Multiplex is failed.
Error Multiplexer failed (Buffy_6x14_older_and_far__2)
Info Finished Multiplex - 1 error(s), 0 warning(s)


and here is what i get when i verify the track.


Info === Verification Buffy_6x14_older_and_far__2 ===
Info -- Total bitrate --
Info Main video bitrate = 2048000, data = "Buffy_6x14_older_and_far__1"
Info Audio stream ID = 1, bitrate = 192000, type = AC-3, data = "Buffy_6x14_older_and_far_"
Info Sum of audio bitrate = 192000.
Info Total bitrate = 2240000 [ audio + main video ]
Info === Finish.[Verification] ===


i believed it to be that the files were just goofy... so i got completely new versions of the same material (i.e., encoded by someone else in a different format -- completely different files) but get the same errors. i'd think that meant i was doing something stupid, but i'm doing the same thing i did for the previous 14 episodes... and they worked fine. is there a minimum bitrate allowed? how could i make sure that it never dips below that, if so? if i encode in MPEG1, how do i do that... and will it be DVD compliant?

thanks in advance!

[clafferty]

if it helps... i just tried a test by encoding one of the files at 720x480. Scenarist accepted that at 2000kbps. i do not know why. the original is 352x240... and it accepted all the others at the original resolution.

can i mix resolutions like this on the same DVD? it's going to take a while to reencode the whole file like this... so i guess i'll find out. any other suggestions are, as always, welcome... :)

[auenf]

you can mix resolutions on a dvd, but you can only have one resolution and aspect ratio per VTS.

Enf...

[DIggedy]

auenf: Why is MPEG-1 preferable for that resolution? Just curious thats all.

[clafferty]

actually, i mixed resolutions in the same VTS successfully.

[auenf]

Originally posted by DIggedy
auenf: Why is MPEG-1 preferable for that resolution? Just curious thats all.

there is no compression benefit of using mpeg-2 at 1/4 D1, unless you want higher than 1.8mbit (the limit of mpeg-1 on DVD), and im not exactly sure if the dvd spec 'officially' allows mpeg-2 at 1/4 D1.

Enf...