How to reduce file size ?

[marcelr]

I would like to get some advice on how to reduce the file size of mpg file.
Have encoded a 700 mb avi file to SVCD. 44000 hz, 480*480 resolution, microsoft audio compressor, divx videa compressor.

The mpg outfile is almost double the size of the original file.

What could I do to reduce this output file (reduce hz, use other compressors, etc).

Thank you for your advice.

[mats.hogberg]

Confusion! SVCD is MPEG2. DivX is MPEG4. Only thing that dictates final file size (besides length (in time) of movie) is bitrate.
So, if you have really done a SVCD, you haven't used DivX for video and not any MS audio compressor for audio. This sounds more like how the AVI is encoded, and has nothing to do with the size of the final SVCD mpeg.
In your mpeg2 encoder, you can set different bit rates for SVCD video and audio. Using a bitrate calculator, you can, by entering movie length and bitrates calculate the size of the final SVCD mpeg, or, set a certain file size and get what bitrates to use to meet this size. The lower the bitrate, the lower the picture quality. You have to find your own optimum size/quality compromise.

/Mats

[marcelr]

Thank your for your answer.
Yes, I had to re-encode the avi in virtualdub becaue it had a VBR and I wanted CBR. For the avi re-encoding I used an MS audio compressor and DIVX video compressor.
I re-encoded the AVI to SVCD in TMPGenc using the highest possible CBR (2500).

If I drop the bitrate to, let’s say 1500, is this noticable ??? What level is still good ? Thank you.

[mats.hogberg]

OK, so you've got a VBR audio AVI. No need to reencode - that will only degrade quality. Extract the audio part with VirtualDub ("Direct stream copy" under Audio, Save WAV under File. If it's really WMA, then rename xxx.wav (that you just saved) to xxx.wma and convert to wav. (Same applies if it's MP3 audio in the AVI.
This wav is what you use as audio source when encoding to SVCD mpeg in TMPGEnc.
What bitrate to use depends much of what's in the move. High action scenes - Higher bit rate. Around 1600 kbps is the lowes you should go, but you could try VBR with avreage 1600, max 2500, min 300, high motion search precision. This takes longer to encode, but might be worth it if you have a movie with lots of action but don't want to spread it over too many CD's. At 1600 video, 224 kbps audio kbps you'll get about 59 mins of SVCD per 80 min CD.

/Mats

[marcelr]

VBR causes sync problems when I split the file. Re-encode the AVI to CBR and you will not have problems anymore.

[ZippyP.]

VBR causes sync problems when I split the file. Re-encode the AVI to CBR and you will not have problems anymore.

Why do you need to split the source file? Are you using the Wizard in TMPGEnc? Use the Source Range in TMPGEnc to select which part of the movie to encode. Then, after you select your bitrate to obtain the required file size you can use the batch file processing. You can process the entire clip all in one go, creating two mpegs. I don't recommend sqeezing it all on to one CD unless you want to go with VCD which might be acceptable.