A question about the file size of my SVCD...

[TempestGarden]

Hello everyone,

This is the first time I have posted here, but I have been reading the site for awhile and getting as much information as I possibly can. I have become pretty good at converting my Divx/Xvid anime files to mpeg2 and then making an SVCD out of them. There is just one thing that is still puzzling me and I have been searching this forum like CRAZY for days now and I can't seem to find the answer to my question. Here goes...

Is it possible to get a smaller file size for each episode that goes onto the SVCD than what I am currently getting, which is about 480 mb, so that I can fit more than one episode of an anime series on a single CDR?

Okay, here are my particulars... The episodes are about 24 minutes in length, I am extracting the audio and converting it to a WAV file using VirtualDub (which actually ends up being a huge file size). Then I merge the audio with the video in TMPGEnc and create my mpeg2 video which I then burn onto a CDR and create my SVCD. Again, the size is about 500 mb for a 24 minute episode. Shouldn't I be able to fit more than that amount onto one CDR for an SVCD? It seems like I should be able to at least get 2 episodes on a single CDR. What is a realistic amount of 24 minute episodes that you can fit onto a single SVCD CDR? Can someone tell me how to do it without sacrificing the quality? I have a feeling the answer lies in the audio, but I just can't seem to figure it out.

Thanks a lot!

--Jeff H.

[Ripper2860]

If you are using TMPGEnc w/ CBR encoding, try using a 2-pass VBR or CQ (80-85 setting) method. 2-pass and CQ use a variable bitrate allowing for better compression with negligible quality loss.

[ZippyP.]

As Ripper suggests, it's all in the bitrate. Since the video bitrate is much larger than the audio, adjusting the audio rate makes little difference.

If you make the video bitrate 2,000 kbps then you should be able to fit 48 minutes on a CD with a little room left over. You can adjust it in the bitrate setting window of the TMPGEnc project wizard. Adjust each project so that it is 50% of a disk.

Also, like Ripper suggests, you might want to try 2-pass VBR encoding in order to preserve the quality. VBR allocates lower bitrates to low action scenes and higher rates to fast motion scenes, allowing for a lower average bitrate..hence smaller files that still look good. A 2-pass setting of 200 minimum, 2000 average and 2500 maximum will be very good. 2-pass takes twice as long so I usually set a batch encode and let it go overnight.

CQ is a type of one pass VBR but the file size is unpredictable.

[TempestGarden]

Okay... thanks so much for both of your help!! I am doing exactly what you both suggested right now and I am waiting for it to finish encoding to see what my final file size will be. At least I will hopefully be able to get two episodes per CDR instead of just one, which seems like a big waste of CDRs to me. I'll let you know about my results.

--Jeff H.

[reboot]

With questionable quality avi's, I use the settings ZippyP suggested above, 2 pas vbr, and the same numbers. The resulting mpg size may be too large for a CDR, depending on the original avi, amount of motion in it, etc.
Tmpgenc reports about 3 hours to do a 650 meg avi, so his idea of setting a batch, and letting it go overnight may not apply. It's all up to your CPU. If you have a very speedy system, it could take as little as 2 hours, or with slower system's, as long as 8 or more.

[TempestGarden]

Okay... I meant to post this sooner than now, but here goes... I did the exact same settings that ZippyP suggested above and everything came out quite well. The file size was around 395 mb instead of close to 500 mb that I was getting before, so I have no problem getting two 24 minute episodes per CD-R. Now, the resulting video quality was still quite good, but I guess the point that needs to be made here is that the original AVI file was pretty high quality to begin with, so I expected to get fairly decent results as it is. So, all is well with this particular issue....

One more question exactly like this, only pertaining to making DVDs this time. Since SP mode is generally 2 hours, theoretically I should be able to fit a good 4 episodes of 24 minute length each per DVD-R. I am assuming that in order to do this, I am going to need to fiddle around a bit with the settings for putting these on DVD just as ZippyP suggested I do when I make SVCDs. So.... what do you guys use for your bitrate settings when you make DVDs, assuming that you were faced with my scenario of trying to fit 4, maybe 5 episodes of 24 minutes each on one DVD-R without sacrificing too much video quality?

Thanks, by the way for the SVCD video bitrate suggestions. I really appreciate it!

--Jeff H.

[ZippyP.]

To convert your files to DVD there's two resolutions that you should choose, 352x480 (1/2 D1) and 720x480 (D1). If you choose 1/2 D1 at the same bitrate settings (2000 avg) as your SVCD it will look quite similar to SVCD and you will get 4 1/2 hours on a DVD, or about 11 of your 24 minute episodes. If you choose D1 then you will need to increase the bitrate, 3800 avg should be good which will give 2 1/2 hrs on a DVD, or about 5 episodes. The min and max values should be as low and as high as you can go in DVD.


The DVDrhelp bitrate calculator is a great resource.

1/2 D1 is also called CVD and there's templates for it in the Tools section. D/L them and put them in the template subfolder, they'll be there the next time you start the project wizard.

Good luck!