TMPGEnc cutting - why is it making the file bigger?

[housepig]

hey all -

hoping a TMPGEnc guru can help - I have a mpeg that's about 2.5 Gb. I opened it in TMPG and set it to cut about 16 seconds from the beginning and about 20 seconds from the end, using the Mpeg Tools Merge & Cut.

File processed fine, I got the length that I wanted... but the file is now about 2.65 Gb! Why would cutting 35 seconds ADD 150 Mb to the file?

couple notes - this was captured with NeoDVD in mpeg2, with quality set to high. I did not change any default settings in TMPGEnc when I did the cut, just went to Mpeg Tools and set my in and out times.

it's not super critical (obviously it will still fit on a DVD-R) but I'm just curious why this would happen.

Any ideas?

thanks for any info.

- housepig

[guitarplayer]

iam having the same prob peeps help us!!!!!

[txpharoah]

It could have to do with the whole header rewrite issue. My guess.

[disturbed1]

Due to padding.

If your max bitrate is set at 9000, then it pads the entire stream to 9000.

If you demux your files will be smaller. Doesn't really matter since all DVD authoring apps will demux the file first before creating VOBs.

[Pussylips]

You have the old PADDING problem. I used to get this with SVCD. Can't remember how to get round this but try this. Think it prefers you to encode using ES Audio & ES Video in TMPGenc then join together. If I remember Iwill let you know!

[Hardcoreruss]

You are getting the problem due to the rewrite of the svcd header.

[guitarplayer]

ya thats my prob i take say 800mb file and split it in half say 400mb then i take it to tmpg to make a svcd and makes it over a gig. why is that.

[killmore]

I have seen once a VCD shrink from 850MB to 690MB.

I needed to cut in order to fit on 2 volumes but once I cut I got 2 files both less than 350MB.
So they fitted on one CD

[SenorDogoLoco]

I know this is an old thread, but I am experiencing the same "feature" of TMPGenc and there doesn't seem to be a conclusive answer here. It has been suggested that a size increase from TMPGenc merge/cut function is due to PADDING from the bitrate settings. This is confusing to me because I thought from reading several other threads that TMPGenc did not re-encode MPG files when using cut/merge. So if it is PADDING to a higher bitrate setting than the input MPG file, that would imply reencoding. It was also suggested that the PADDING side effect was irrelevant because DVD authoring will demux (thus I assume de-PAD) when creating the VOB.

So what should I do here? Not worry about the PADDING, since I will be authoring later, or first figure out the max bitrate of my input file(s) and change the settings in TMPGenc appropriately, so I neither loose quality nor have excessive PADDING. Am I understanding correctly that the MPG settings actually play a part in cut/merge? I had previously thought they were irrelevant, because TMPGenc didn't re-encode.

[SenorDogoLoco]

Well, if anyone is interested, I answered my own questions with a little bit of experimentation. TMPEgenc truly does a "pure cut" without any re-encoding. No matter what I changed the MPEG settings to, the cut always turned out exactly the same size ... identical to the source file. I don't know why the one clip that I cut ended up larger, except that it was a very, very small clip and maybe re-writing the header had something to do with it. All of my subsequent tests resulted in smaller files when cutting.