What TMPGenc bitrate to use?

[Almost Human]

When I capture from my cable box the average bitrate captured at 352x480 in VirtualDub is around 4000 on letter-boxed movies. When I encode to MPEG-2 (352x480) 2-Pass VBR, is it a waste of resources to use a 5000 bitrate? Will it make any difference at or above what it was captured at? Thanks.

[holistic]

Last time i used VirtualDub , it didn't capture in MPEG2 so i will (go out on a limb here) and guess you used some form of *.avi codec . Sooooooo 4000 of WHAT ?!

Again ! (and i am not a mind reader) , looking at the res of 352*480 i am also going to have to guess you are making cvd (1/2 DVD). Therefore a mpeg2 bitrate of 5000 is more than sufficient for your needs --- BUT --- If this is going on a CD , IT WON'T FIT - for DVD, it should depending on length (time) of movie.

In order to get the answers you seek you must ask the right questions .(or at least supply more info)

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[Almost Human]

OOPS!

Capturing AVI at 352x480 using Huffyvu 2.1.1 in VDub, average bitrate observed is around 4000. I want to use TMPGEnc to encode to 1/2D1 for DVD burning. Would using anything over 4000 average bitrate in TMPGEne be a waste of time or resources?

[ZippyP.]

I think that you're trying to compare the bitrate in your avi and the bitrate of the mpeg. The compression schemes of the two are quite different so you cannot equate the bitrates, at least not 1:1. A 4,000 average bitrate for a 1/2 dvd mpeg does seem pretty high, but I think you will have to decide how low you are willing to go. I have encoded at 1/2 dvd resolution from a dvd rip with an average at less than 2,000 and it looks pretty good to me.

[DJRumpy]

Just use one of the bitrate calculators in the TOOLS section (I'd suggest you try the one owned by this site, as it's easy to understand).

Since your going to DVD, and you know the length of your video in Hours, Minutes, and seconds, you simply plug in the length, the type of media (DVD in your case), and it will tell you what Average bitrate to use. Using too much bitrate will not hurt you in any way. It's rather wasteful, but not harmful.

If you plan to place multiple videos onto the same DVD, then bitrate becomes more of an issue. Again, you should use the bitrate calculator to get the highest possible Average bitrate for the combined length of your videos, while keeping your output small enough to fit onto your DVD.

[Almost Human]

Thanks ZippyP and DJRumpy.

So there is not any direct correlation between the captured AVI bitrate and the MPEG encoding bitrate. I usually just use whatever encoding bitrate will fit on the DVD.

Through trial and error, I found that if I raise the MAX bitrate to at least 2000 above the AVERAGE, the resultant output produces less pixelation during rapid movement. On someones recomendation I was using 5000-4000-1000, now I use 6500-4000-300. After burning the same movie to DVD+RW using both, the 6500-4000-300 was noticably cleaner (smoother).

Thanks again.

[ZippyP.]

I usually just use whatever encoding bitrate will fit on the DVD.

That's the best way to go, of course what looks good to you is the determining factor! 8)

[DJRumpy]

Correct. There is no correlation between bitrate for say, Divx (MPEG-4), and bitrate for MPEG-2. They are very different, with different capabilities, compression ratios, etc. Apples to Oranges. Huffman doesn't utilize a bitrate setting in the normal sense. It just captures the video in uncompressed format and then compresses using ZIP compression methods (gives about a 2:1 compression ratio)

Since your using half D1, anything above 4000 should look good, assuming your source is decent. You should also use Multipass VBR, rather than CBR. It will allow the full range of bitrate for DVD ( 0-9.8Mb/second ), improving your quality.

The bitrate calculator will remove any guesswork on what Average bitrate to use, as it will allow you to use the highest possible, without creating an MPEG that's too large to fit on your DVD.

Your MIN setting is fine. I would bump your MAX at least up to 9000. No reason to cap it at 6500. It's doubtful that Half D1 would ever need to go that high, but if there was enough motion, and enough noise in your video it could easily need more. 9000 is well within DVD specification.