SVCD questions

[thoughton]

I've done a bit of reading on this but I seem to get contradictory answers ...

Does standard SVCD format use constant bitrate or variable bitrate? I had always thought it was constant but now I'm starting to wonder.

Part of the reason is that the other day I was testing MPEG2WORKS and encoded one of my own DVDs into SVCD and it came out as a 790MB mpeg and a 250MB mpeg. However when I encode the exact same DVD to SVCD with forty-two I get two 705MB mpegs and a 30MB mpeg.

I was wondering why the file sizes are so different (as expected forty-two's much larger SVCD output looks a lot better in terms of picture quality). Both programs are used on default SVCD settings. I thought maybe one of them is using variable and one is using constant as default (of course I am probably completely wrong! )

On a related point, in a very informal test (only 1 movie) it seemed to me that NTSC SVCDS are about 10-15% smaller than PAL ones. I presume this is because of the higher PAL resolution and despite the lower framerate. Is this size difference likely to be constant across all SVCDs or will it vary a lot depending on what type of movie it is? (I was going to do a few tests but thought I'd ask here before I spent hundreds of hours encoding a range of movies).

Thanks for any suggestions!
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[SERBIAN]

In latest version of MPEG2 Works there is a section named "custom" where You can input encoding bitrate and frame sizes...You can use that section for testing...As You presumed all encodings are in VBR...You can get much better quality there, but note that some custom encoded S-VCDs wont play on every standalone DVD players...I made DVD and SVCD presets following very strict standard of external players...So those files are playeble in 99% of old and new players....

I would like to suggest You to use smaller movie for testing...Youll get result much faster...And also find a sample movie with lot of motion in it...Thats the best way for testing quality of encoding...

Regarding PAL and NTSC sizes...It depends of what type of the movie is...If there is a lot of still scenes and a few large scenes with motion the differnece in size will be constant...

But it is always the best way to do the tests and to see what will come out...