SVCD editing - make a little smaller

[jolo]

Have 2 SVCD files from a movie. Both are very good quality. Both are about 750MBs big, too large for a CD.
I know I can split them up into three CDs (use Tmpgenc) and not lose quality, but I would rather have them both fit on 1 CD, therefore being able to watch the entire SVCD movie on a total of 2 SVCDs.
What can I use to have them changed so that I can reduce their sizes to 700MB each ? When I encode, I always make SVCDs 480x480.

Here are the properties of each of the MPEG-2 files.

Stream:
Type: Interlaced MPEG2
Bitrate: 2.500 Mbps
Framerate: 25.000 Hz
Resolution: 480x576
Aspect ratio: 4x3

Stream:
Type: MPEG Audio
Bitrate: 224 Kbps
Number of channels: 2
Sampling Frequency: 44.1khz

Thanks in advance

[snowmoon]

Um... why won't 750 fit on a 74 minute disc?

Mabye you have forgotten that SVCD, VCD, and music use mode 2. Mode 2 supports farger files at the expense of error correction becuase a small error is likley to go unnoticed in these formats, but would have been unacceptable on a DATA disk.

74 minute DISC = 740MB +- 20MB based on menuing and overburn
80 minute DISC = 800MB +- ...

Cheers.

[jolo]

This is definately new news to me.

I thoought 74 minute CDs write 650MBs of info and 80 minute wrote 700MB of data.

Are you saying that I could just burn away in Nero without any changes and I will get this added disk space ?

:P

[TheVore]

Interesting one this. I've had a similar problem.

In theory you can get 74 mins of vcd/svd on a 740M disk and 80 mins on an 800M disk, I've read this all over the place.

My experience:
1) I created an svcd file of about 766M it was a 74min video clip using TMPenc and following the spirit of http://forum.vcdhelp.com/userguides/84759.php
2) Then did the vcd header trick http://www.geocities.com/newestmoviesencode/dvdvcd (so that the standalone player would read it) and the file ended up a similar size.
3) Used Nero to burn cdrw and plugged the file into this but nero complained that there was not enough space on the disk and it displays total disk space need as over 800M and time as 84 min. I was surprised to see Nero add nearly 100M - this didn't seem right ?????????????
4) I re-created the svcd file again (another night gone) and it was 714M, did the header trick to vcd, and ....nero burnt it ok 799m on an 80 min cdrw. Oh by the way - the disk didn't play properly after that! So, I've started again - It's a really good idea to use the range settings in TMPGenc to create small test video clips.

So... Question is are there settings in nero that we should be changing to do this correctly ? Should compliancy be on or off ?

[Hansiman]

You must be doing something wrong. I burn SVCD with Nero 5.5.
Files that are 780MB will fit on a 80min recordable. Nero even gives the size in bytes in its explorer, that size is 818 million bytes.
But, when burnt in mode2, the size is reduced by app. 10-11%. So, the 780MB file becomes a little less than 700MB in mode2. And that fits easily on a 80min recordable.

Hans.

[fatdom]

Why don't you buy 99min/900Mb CD-R. I have been using them for a while now and have had no problems. They burn without any errors at speeds up to 16X and cost in the UK 11.75 (pounds) for 25. They also play fine in my standalone (Toshiba 220SE).

[snowmoon]

TheVore: When you do the header trick sometimes it just doesn't work right ( I've had this problem too ). The VCD software had to pad the file to make it proper and the padding is what puts it over the top.

74 minute disc = 740MB of mpeg
80 minute disc = 800MB of mpeg

These numbers are assuming that you mpeg's don't need to be repacked on the fly ( properly done they do not ).

[TheVore]

I tried another conversion from a diffent avi toproduce another svcd and again did the "header trick". File size ended up similar to to one that gave me problems before. However, this time Nero behaved as you'd expect and there was no problems burning the disc. The result was a pretty good picture though with a bit of jerkyness. I reckon snowmoon must have been right about the padding.

[jolo]

Great discussion, I thank all of you.

I have done the "header trick" many times with success, even with a CD encoded with Ligos LSX, for the heck of it and it worked great.

I am also wondering of doing the header trick when the file is a PAL file might have something to do with it. It seems like my successes have been with NTSC ?

Could someone please explain the Pad option in Nero and what it does ?

[DJRumpy]

It sounds like your making this for more complex than it needs to be. If your using nero, simply try to burn your videos. It will warn you if the video will not fit, and give you an option to overburn if the video will probably fit. If the video is simply too large, it will tell you so.

Use an CDRW if your don't want to risk making a coaster.

[jolo]

Nothing like a simple answer !! Thanks DJRumpy.

First, I started this string to asking about a situation where I already have a SVCD/MPEG-2 file, and I it might take 2.5 CDs, but I want to modify the MPEG-2 file to make it fit on two and sacrifice a little quality. What tools to use and how to do it. Never did really find that out.

Then it get into the Panasonic think, which I happen to do myself, where I only plays VCD, but if you create a SVCD (MPEG-2) file, then change the header via Tmpgenc (I do it using the MPEG tools, merge join option), to stay standard VCD, it allows the stand alone DVD player to play SVCDs when it says that it doesn't support it.

So there are really two issues on the table.

[DJRumpy]

Hmm. To resize an SVCD, you could use any number of tools. I would suggest DVD2SVCD if you want the one click option (it will accept MPG as input I think..if not you will have to extact it to AVI). It will let you specify the number of target disks (2 in your case), in a round about way, and it's pretty much one click once it's set up.

If you want to get your hands dirty, I'd suggest re-encoding with TMPGenc, using 2-Pass VBR (Settings button | Video Tab | Rate Control Mode button ). Start it using the wizard, and it will give you a gui showing approximate size of your end project.

If you want to spoof the SVCD headers to look like VCD, I think there is a sample here that you can download (check the VCD and SVCD sections on the left for help). That should tell you if your player will handle the spoofed SVCD.

[SVFive]

Hey is what Hannison said correct about a 780MB file SVCD fitting on a 80min CD-R that Nero 5.5 can burn. Then what about a regular VCD instead of SVCD, will that still fit on a 80min CD-R my problem is similar to jolo, but im trying to burn a VCD which is about 791MB in size to a SONY 700MB 80min CD-R disc.

[Gargoyle]

Hansiman is on the right track, he/she just has it backwards- the file size is not reduced, but the available data area on the disc is increased -
Mode 2 is a CD format which doesn't use or contain error correction data; so the space normally used for error correction is available for data storage.
Audio CDs and S/VCDs use mode 2- thats why CDRs are listed as 700M(mode 1)/ 80 minute (mode 2).
Here's a more technical explaination from VCDImager.org:

2.2 Anatomy of Video CD's

Basically a Video CD is made up of CD-ROM XA sectors, i.e. CD-ROM mode 2 form 1 & 2 sectors. Non-MPEG data is stored in mode 2 form 1 sectors with a user data area of 2048 byte, which have a similiar L2 error correction and detection (ECC/EDC) to CD-ROM mode 1 sectors. While realtime MPEG streams is stored in CD-ROM mode 2 form 2 sectors, which by have no L2 ECC, yield a ~14% greater user data area consisting of 2324 bytes.

http://www.vcdimager.org/pub/vcdimager/manuals/0.7/vcdimager.html#SEC6