Muxing with TMPGEnc vs. bbmpeg

[zizou108]

Hello,

Could anyone tell me why a SVCD mpeg muxed with bbmpeg is significantly larger in bytes than the sum of the audio and video, while in TMPGEnc, it is almost exactly the sum of the source files? I.e., why are bbmpeg SVCDs larger than TMPGEnc's?

The TMPGEnc-muxed SVCDs play fine in my Pioneer DVD player, but some folks seem to think that bbmpeg is superior for muxing. I'm not sure why.

Thanks very much,

zizou108

[adam]

Well theres always overhead added when the program stream is multiplexed but the reason bbmpeg's overhead is more is because by default it alligns sequence headers and adds Svcd Scan offsets. If you uncheck these than the resulting filesize should about equal to TMPGenc's. TMPGenc doesnt even give you the option of alligning sequence headers or implementing scan offsets, and while this doesn't make the resulting svcd non-compliant, it does make it far less compatible with hardware svcd players.

Many, if not most dvd players use the sequence headers and scan offsets to maintain sync during playback and essecially during seeking. Your current dvd player may play your svcds fine but I can guarantee you that there are alot of dvd players out there which won't be able to maintain sync on the svcds you author with TMPGenc.

The amount of space the added overhead uses varies but on average bbmpeg's output is going to be about 20MB's larger than TMPGenc's.
In my opinion thats a small price to pay for the added compatibility.

bbmpeg is a superior mpeg2 multiplexor compared to TMPGenc because bbmpeg's output mpgs are far more compatible on hardware players. Also bbmpeg allows you to customize all aspects of how your mpg is multiplexed and this is an absolute must for those who make xsvcds.

[zizou108]

adam,

Thanks very much for the info. Your answer makes a lot of sense - I'll keep it in mind. I think I have avoided some of the problems you mentioned by using VCDEasy to burn my SVCDs, which re-calcs SVCD Scan Offsets (it recommends this when it sees a TMPGEnc file).

zizou108