svcd quality with 60 minutes at least on one cd?

[Freaky]

I'm wondering which encoding process , or settings, i should use to fit a minimum 60 minutes of video onto a cdr while using mpeg2 compression.

Like, If i encode a cvd at 352*288 25fps and a constant bitrate of 1150, will that look better or worse than vcd?

I'm really trying to get a good mix of quality and quantity, because who wants to get up every 30 minutes to swap cd's?

[adam]

Well if you used those settings it would just be a non-standard svcd (xsvcd) not a cvd and at those settings it would probably look about the same as a standard VCD, if anything worse. With these settings there really wouldn't be any point to using mpeg2, you could use mpeg1 instead and your video would actually be compliant.

You can fit about 1 hr in good quality in SVCD format, if your source is fairly compressible (widescreen, not too much motion, ntscfilm or pal etc...) If you want 1 hr min per disk then SVCD and CVD are not for you. You are best off using standard VCD and getting 80 mins per cd, or using xvcd and tweaking your bitrate per movie to fill the disk.

SVCDs do not fit 30 mins of content per disk. Any such disk would literally be non-compliant. If you use CBR at the max bitrate allowed you will still fit about 40 mins per cd, and even this is extremely impractical. Using VBR and good encoding techniques you are going to get between 50 and 55 mins per disk in very high quality, and as much as 60-65 mins in acceptable quality. Most movies fit comfortably on two 80 min cdrs, which is exactly how many a VCD would use. Even for those movies which require 3 cds, you still only have to get up twice. You could also do what I did and buy a 3 disk changer.

[Freaky]

I thought mpeg2 was supposed to be a higher quality codec, and if i used 1150 as the max and 0 as the min wouldn't that give me a slightly longer and better looking movie than a compliant vcd?

[Freaky]

oh and, wat settings do you use to get 50 to 60 mins on a svcd?

[adam]

Mpeg2 is an improvement over mpeg1, but most of those improvements are geared toward higher bitrate. The main benefit of mpeg2 is that is supports interlacing, so with that in mind, I suppose my previous answer wasn't entirely accurate. If your source is interlaced than the xsvcd (352x288 mpeg2) should look better than the VCD, but still not that much. Mpeg2 supports some additional features, such as multiple audio streams, up to 4 selectable subtitles, and of course interlacing. If you do not use any of these, and you are aiming at low bitrate, ~1MB, than you should stick to mpeg1.

If your max is set to 1150kbits than in any given scene you are still getting no more bitrate than a standard VCD. By using VBR with a max of 1150kbits you may be able to get the same level of quality as a standard VCD and squeeze in a little more content, but the quality won't be better. In actuality, the effectiveness of VBR is incredibly limited with a bitrate that low. It only has a real interval of maybe 100kbits to work with, and VCD's bitrate is already so limited, in my opinion it will probably look worse than a standard VCD. Of course you could always just raise your max, but again VBR is just too limited in this instance to yield any significant quality increases.

55 mins is about the cutoff point for me to make a SVCD. I could go higher but I choose to use CVD instead in these instances. CVD is essentially the same as a SVCD except that it uses a resolution of 352x480/576, so you can get away with a lower bitrate.

As for my process, I simply prepare my source as best as possible before encoding. I keep it ntscfilm (doesnt apply to you since your pal) I crop and add borders (accounting for overscan) I use light softening filters etc...

Other than that, I simply use FitCD to calculate the correct bitrate to use to make my movie fit on either 2 or 3 cds, which typically gives me between 50 and 60 mins per disk.

[Morloc]

I am far from being an expert and cannot debate the fine points of CBR vs.VBR at various bitrates, but a while back, I too wanted something better. I tried one of Kwag's TMPGEnc templates, and am extremely pleased with the results. I now burn all my VCDs using his 704x480(NTSC) Plus template. It yields an average of 60 min. per disc and the results have impressed my friends so much that they have switched as well. Results are very close to DVD original (I have played them side by side). You can get samples and try them yourself here:
http://www.kvcd.net/dvd-models.html
I can't give you all the settings that it uses but bitrate is 2300 max CQ.

Morloc

[Freaky]

thanks both for your help, ill try those templates.