file getting bigger after using cce multipass

[DVDragon]

After doing a 3 pass with a max. of 4000 min. of 0 and an average of 2000, my 1.62 GB file turned into a 1.88 GB file. Any help would be greatly appreciated.

[xnakx]

are you re-encoding a mpeg file?
are you processing audio seperatly?
is the source mpg2 or 1?

XnakX

[DVDragon]

i'm using the doom 9 guide "getting the best out of cce", after doing the one pass i did the multipass and it made the file bigger for some reason. i think i used a maximum of 7 or 8,000 on the first pass, if that helps any.

[Justinus]

@DVDragon

CCE is very smart software :rolleyes: It'll exceed the max bitrate in the case of Q factor is very high to maintain the quality of pictures. Therefore, this is the well-known problem here :D

AFAIK VAF is required to do multi-pass M2V. It'll be generated during the first VBR encoding if CCE can't find VAF file in the first place. I think that the first file you got with the size of 1.62GB come from one-pass VBR. When it finished, you selected multi-pass (in your case, 3-pass), and then it overwrote the old file and did 3 passes. That's the reason why your file got bigger (1.88GB) ;)

I think that VAF is just like pre-encode file. It contains every information of your video stream. Once, I accidentally selected the aspect ratio of 4:3 to create VAF, then when I tried to encode with the aspect ratio of 16:9, I got 4:3 instead. It seemed it used the first setting (when I created VAF file) as a comparison to the current setting (when I created M2V file). I noticed that if I used different bitrate setting to create VAF file, and used the same setting to create M2V file, when I checked an average value of Q factor in Advance mode, the value was different :confused:

I still can't figure it out how to control the max bitrate though. There's another way you can try. Go to advanced mode and use local bitrate to limit some part of the movie that consumes the most bitrate. That might help :)

[DVDragon]

Ok I think I understand now. The way I was doing it before I was not "re-writing" the VAF file and the file was getting smaller, so I guess that is what it was. Thanks for the help.

[Justinus]

As long as VAF file are detected by CCE, it'll never create or re-write VAF file again though it will accumulate more and more data each time you make VBR multi-pass to make the movie quality better. That's why the bitrate is likely to swing a lot, and maybe exceed the max bitrate you set, when you do multi-pass comparing to CBR or one-pass VBR ;)

Notice that after you create VAF file and try to encode movie again, it'll skip the step of making VAF file. This might come in handly if you want to encode this movie again with the same configuration otherwise a new VAF file is needed to create.