How to keep the quality and reduce the file size?

[Conqueror]

Guess what I did today? I converted "The Mummy Returns" DVD to Divx and the quality was Superb. I can't tell the difference between this and the original DVD. But the thing is, the size of divx movie is 15MB per minute. The movie is 129 minutes long, so if you work it out, it comes to about 1935MB, which is about 3 lots of 650MB CD-Rs. I want to reduce this to one CD or 2 maximum. What can I do to reduce the size of the movie? I still want to keep the same quality. The audio is already compressed to mp3. I used FlaskMPEG to do my conversion.

Here is information about the divx movie clip I made:

Image.
Resolution: 720x576

Audio.
Bit rate: 96kbps
Audio format: MPEG Layer-3

Video.
Frame rate: 25fps
Data rate: 256kbps
Video sample size: 24bit
Video compression: Divx codec


I've been hearing a lot about the TMPGEnc and VirtualDub but have never used them. Are they good as they sound? Can I use my Divx codecs with those software? Would using these software match the quality of the movie I made, and also reduce the size of the file?

How can I reduce the size without harming the quality of the movie? Please help.

[Conqueror]

Oh I forgot to say that my original DVD is sitting on my hard drive in VOB, IFO and BUP file formats. Can TMPGEnc and VirtualDub software read from these file formats?

Also, the original movie is in wide screen. Would trimming off the black borders above and below the movie help to reduce the output file size? But how do I trim this and yet keep the aspect ratio to wide screen?

One last thing, I want to make an SVCD (with clickable menus etc.). Is there a guide that would teach me how to do this? Could some please give me the link.

Thanks in advance.

[vitualis]

You need to reduce your video bitrate rate for your DivX if you want to fit it on one disc.

As for SVCD, there are excellent guides at http://www.doom9.net (there are guides for DivX too). You cannot make "clickable" menus on a SVCD and I hope that you realise that the video on a SVCD must be in MPEG-2, not DivX.

Regards.

[Conqueror]

OK. I've been messing about with the bitrate for the video and audio. I got some wierd findings.

I started by reducing the bitrate to 256kbs for the video and 128kbs for the audio. The resolution was set to original DVD (i.e. 720x576). I made only a 30 second movie just to see its quality and size. The size was 5MB (for 30sec movie) and the quality was excellent.

So then, I thought let's make the movie a bit longer. I made a 2 minute divx movie and I was shocked at the results. The quality was somewhat the same, but the size of the movie was 56MB!!!! (for a 2 min movie).

Why did that happen? All my settings remained the same for both my tests. I only made the movie a bit longer.

My reasoning is that after the first minute of the movie, there is a lot of fast action, and so the bitrate is stepped up automatically to keep the quality the same.

The final movie was done in 481kbs even though I selected 256kbs. What's going wrong?


-quote-
You cannot make "clickable" menus on a SVCD and I hope that you realise that the video on a SVCD must be in MPEG-2, not DivX.


But what about those menu sceens where you have to select a number to play the main movie, and select another number to play a certain scene from the movie? I watch these on VCDs all the time. For example, as you insert your VCD into your CD-ROM drive, the menu pops up and it asks you to select "1" to play the movie and select "2" to play a song (which is part of the movie).


I was aware that VCDs/SVCDs use MPEG format which has to be in standard size and standard bit rate for the audio. My question was off the main topic of what I wrote about. Anyway, thanks for your reply. I will check that website out.

[vitualis]

But what about those menu sceens where you have to select a number to play the main movie, and select another number to play a certain scene from the movie? I watch these on VCDs all the time. For example, as you insert your VCD into your CD-ROM drive, the menu pops up and it asks you to select "1" to play the movie and select "2" to play a song (which is part of the movie).

Oh I see. I thought you meant where you could move a cursor around and physically "click" on a hotspot (e.g., on VCDs on a CD-i player and some software VCD players).

Yes, you can make SVCDs with menus.

VCDImager is one of the most powerful and flexible S/VCD authoring systems and you can use it with a GUI like VCD Easy or TSCV.

http://www.vcdimager.org
http://www.geocities.com/medinotes/vcd
http://www.vcdimager.org/guides (mirror)

Regards.