Converting to MPEG2/DVD

[tgc225]

Alright, I captured a raw AVI file of an analogue cable broadcast via a TV tuner card in my PC. Now I have a 40gb 30 minute file that I want to compress. I've decided to use MPEG2 so that I can put it on a DVD and retain most of the quality.

Now, I have a few questions:

1) What's an acceptible bitrate to use? Is the highest possible (8000) overkill for an analogue cable broadcast?

2) I've noticed that TMPGENC produces an .M2V video file, then you extract a WAV file of the audio, then use something like IFOEdit to convert it to the DVD acceptable files to burn and watch on your DVD player. Is there any way to produce an MPEG2 encoded file that you can easily watch on your computer? Like a file that contains both audio and video? I noticed if you choose "System(Video+Audio)" option, TMPGENC produces an .mpg file with both audio and video, but I don't know if you can easily convert that to a DVD disc.

[WuphonsReach]

1) if all you want to fit on the DVD is the 30 minute clip, encode at CBR 8000... you've got plenty of space on the disc, so why worry?

2) TMPGEnc will let you create an MPEG file like you saw... whether or not your authoring application will accept that file depends on which authoring software you use. (TDA wants its source material as M2V+WAV).

[tgc225]

For 1) I was just wondering, because I wanted to have a file on my hard drive in addition to it on DVD, so I was wondering what would be the best way to maximize quality, and if there were any tips to make the size a little smaller.

Speaking of 8000kbps, how does a MPEG2 video encoded in that bitrate compare to the original RAW AVI? And just out of curiousity, what kind of bitrate would be needed for XVid/DivX compressing, to have a similar quality to a 8000kbps MPEG2 video?

Thanks! I'll try to see if any DVD authoring programs accept MPEG2 encoded .mpg files.

[jimmalenko]

Firstly, let me say that you have a pretty good grasp of what you need/want to do. I think all you need is a nudge and not to be dragged, which is excellent.

As soon as you mention the "q" word (quality), you open up a can of worms. What is acceptible and good to me could be crap to you. The best way to find out what bitrate you should use is to create a 30 second clip and test a few different bitrates on it. Use a CD-RW or a DVDRW to test on your standalone DVD player as well. We can suggest what we have used with success in the past, but our standards could be different to yours.

[tgc225]

Thanks How do the formats compare anyway? How does an 8000kbps MPEG2 video look compared to the original AVI or something like a PICVideo MJPEG 19 quality video? And how do high bitrate DivX/Xvid encoded files look? I'm just curious as to how much the quality changes when coverting these formats, since I haven't found anything online.

[mmasw]

... whether or not your authoring application will accept that file depends on which authoring software you use. (TDA wants its source material as M2V+WAV).

what makes you say that?

TDA will certainly accept those as source material. But it will take other files as well. It will take multiplexed MPG1 & MPG2; it will accept mp2 and even AC3 audio; it will accept dvd folders, re-jigged vob's; it will accept vcd-compliant mpg1. You can throw a lot more at TDA then M2V+WAV.

you shouldn't make such a declarative statement if you're not certain of the facts.

[mmasw]

Thanks How do the formats compare anyway? How does an 8000kbps MPEG2 video look compared to the original AVI or something like a PICVideo MJPEG 19 quality video? And how do high bitrate DivX/Xvid encoded files look? I'm just curious as to how much the quality changes when coverting these formats, since I haven't found anything online.

you started with an analog source, and even though you have a massive 1.3gb/min bitrate there will most likely be some video noise in your source. If you run the avi through TMPGEnc without filters and at CBR you'll have less quality then multipass VBR with filters. In other words there are a lot of variables inherent to your question.

With that kind of source bitrate, and if you tinker with the MPEG2 encode, you should get minimal quality loss during compression.

Divx/Xvid are designed for compression, so if you used VDub, for instance, to convert your source to an 8000Kbs DivX file, it would most likely look better then the MPG2. As a matter of fact, with a good use of VDub's filters you might make a DivX/XVid encode look slightly better on your computer then the source, and at a bitrate less then 8000Kbs.

Instruct yourself: make a 1 minute clip from your 40GB avi by using VDub. I'd cut it so you have some high motion, light transitions, color transitions etc. (very easy to do with VDub). And then experiment with various encoding to see what suits you.

[tgc225]

Thanks, I'll be sure to play around with VDub and XVid/Divx and see what I come up with,