Why does the file get huge when converted?

[BuffMovieBuff]

I bet this has been asked before but this is my first post. When I convert a movie from divx to mpeg for viewing on my dvd player the file becomes huge and I have to split it and put it on two cd-rws. Is there a way I can reduce the size of this file so I can fit it on one cd?

[Vejita-sama]

Different bitrates and compression. MPEG4 (ie DivX) is highly compressed MPEG1/2 is not. The standard VCD bitrate is video=1150kbit/s and audio=224kbit/s. That's the size of the encoded MPEG. So the only factors that affect size are the bitrate and the source runtime.

The size of the source, the resolution of the source and the resolution of the MPEG have ZERO affect on file size. Useing the standard VCD spec 1min=10MB. So if you have a 60min video souce -> 600MB MPEG. As x(S)VCDs are burnt as mode2 data, you get 740MB on a 74min CD or 800MB on an 80min CD. That is a 74min cd holds 74min of VCD data, and an 80min CD holds 80min of VCD data

To get more time on a CD (eg. 90min on a 80min CDR) you need to lower the bitrate. But the lower the bitrate the lower the quaility of the encoded MPEG.