Tweaking settings in TMPGEnc

[jyeh74]

I am burning music videos onto a dvd-r. Total time is about 6.5 hrs. When I use the bitrate calculator, it says my bitrate for this particular compilation is about 1323 kbit/s. I heard from some members that vcs is about 2000 kbit/s.

So my question is, on my output settings, can't I just make bitrate = 2000 and then DVD shrink it to make it fit? Or will it be the same poor quality if I use 13023 kbit/s without having to shrink it?

Thanks!

[redwudz]

If you made it 2000 and used Shrink it would likely look a lot worse. Your bitrate is not much above the VCD standard of 1150kbps. You should be using 1/2 D1 to get the most from that low of a bitrate for MPEG-2 on a DVD.

See 'What is' DVD for the 1/2 D1 settings. With that long of a video, it won't look too great anyway, but 1/2 D1 will help make the best use of the available bitrate. You didn't mention your audio format, but you might use AC3 instead if you are using MPEG-1 Layer2. That might make a a little more video bitrate available.

[jyeh74]

Redwudz,

I only have MPEG-1 Audio Layer II or Linear PCM. I dont have a AC3, and frankly dont wish to have to go thru the hassle of using additional s/w. What is 1/2 D1? I know I am using a 4.7 dvd-r (Ritek)

VCD standard is 1150? I guess I heard wrong when someone said 2000.
Why would using 1300 be better than using 2000 then dvd shrink-ing it?

Thanks a lot.

[kschang]

jyeh... You didn't follow the advice! Redwudz said to look in DVD definition (look to the upper left!) and you'll find the definition there.

[jyeh74]

One more question, using the bitrate calculator, it says for my length I should use 1307 bitrate. But when I use TMPDEnc, used at 100% of my capacity, it shows 1231 bitrate. IF I use 1307, then it jumps to 105%. If I follow the bitrate calculator, then I will have to DVD Shrink it?

Does TMPGEnc just underestimate bitrate? Should I just leave it at 100% and use 1231 instead of 1307? I know it probably won't make THAT big of a difference, but I was just curious to the technicalities behind it. Thank you!

[redwudz]

Sorry, I left out the part about the DVD spec being on the upper left, but here is what you would want to look at:

720 x 480 pixels MPEG2 (Called Full-D1)
704 x 480 pixels MPEG2
352 x 480 pixels MPEG2 (Called Half-D1, same as the CVD Standard)
352 x 240 pixels MPEG2
352 x 240 pixels MPEG1 (Same as the VCD Standard)

If you are presently using full D1, changing to 1/2 D1 will make much better use of your lower bitrate, likely with less quality loss than full D1 with your bitrate of 1323. And it should look better than a VCD.

Shrink is a transcoder. It removes what it thinks you won't miss. You don't have enough to start with to risk removing any more. The better method is to encode to a lower bitrate in the first place, then you don't need to remove anything.

[jyeh74]

Redwuz,

I thought 720 x 480 pixels MPEG2 would be best since most of my mpg videos are that resolution. Wont using 352 x 480 pixels MPEG2 cut it in half in terms of quality?

Thanks!

[jyeh74]

The 352 x 480 , looks like it kinda squished it, so I am worried it might not maximize my viewing area. The 720 x 480 seems more stretched out. Not sure - what do u guys think?

[manono]

It'll cut it in half in terms of resolution. Although it's going to look softer, it'll work to double it in terms of quality, because the same bitrate is divided among half as many pixels. Also, although no one has mentioned this yet, you should definitely reencode the ones with PCM audio, even if you leave the MP2 ones alone. Your bitrate is so low that it's going to look like crap no matter what you do. It'll just look slightly less crappy at the lower resolution.

Not sure - what do u guys think?

I think you don't know what you're doing, and aren't resizing properly. Either that or your player isn't resizing it properly. You haven't really given many details, so it's hard to know.

[jyeh74]

I am just trying to maximize my quality at the given length on a dvd-r. When it cuts in in half in terms of resolution, will it look full screen? I am trying to maximize it to my dvd player in the car (4 by 3) but the 352 x 480 looks like it will make it smaller than 4 by 3.

[manono]

Yes, it's DVD compliant, as redwudz pointed out earlier. This means, among other things, that it'll get resized properly by your DVD player, assuming you resized it properly for DVD in the first place. Just as a 720x480 full res DVD gets resized correctly for display, so will a 352x480 half res DVD be resized correctly.