Vegas "best" render quality causes DVDA to recompress my progressive file

[Jamie Hellmich]

I'm just beginning to dabble in progressive video, in DVD and Blu-Ray format. I'm looking forward to V8.0c/DVDA 5.0 for the Blu-Ray authoring.

An issue I've discovered, is that whenever I drop a 480-24p or a 480-30p .mpg rendered with "best" "video rendering quality" into DVDA and go to burn, it shows up in the "notification" window as a .m2t file, and DVDA wants to recompress it.

I checked the file properties in Vista, and it shows as a .mpg, as I thought it should. It also shows as a MPEG-2 file in the DVDA explorer window.

I went back to Vegas and re-rendered the same movie with "good" setting, and did not get the message.

Any ideas why?

I wouldn't think it makes a difference, but the original capture files are 1080-60i.


Jamie

[Richard Hunter]

Hi Jamie. I thought that if you rendered as mpg it would have to recompress the audio to ac3, no matter which render quality you select. If the video is not too long, I would render the audio as a wav file, and bring that into DVDA to replace the mp2 audio track.

Richard

[Jamie Hellmich]

Richard, yes it does always recompress the audio, however...

In addition to the notice that the audio will be recompressed, it states " the video {filename}.m2t will be recompressed".

As stated, the video shows up as an .m2t in this dialog box, when in fact it was rendered as and shows up everywhere else as .mpg.

It apparently has to do with rendering to "best" quality in V8.

I've authored probably 75-100 DVD's rendered in 480-60i "best" which DVDA never gave this notice wanting to recompress the video.


Jamie

[Seth Bloombaum]

"Best" is the correct choice for rendering an HDV project to SD MPEG2 for DVD-Architect.

What *should* be happening is that DVDA only rerenders MPEG2 if the video a) does not fit on the disk with a good allowance for audio and menues or b) exceeds the permissable data rate for the DVD standard.

If you're not familiar with planning for disk capacity and datarate, Edward Troxel has an excellent short article in Volume 1 Number 7 of his newsletters.

If all this is old hat to you and you're doing proper disk planning... well, it's still hard to believe that clicking "best" makes a stream that must be rerendered. I always use best when rescaling HD to SD, and I've never had that problem in DVDA.

What exactly are your other render settings? If you're doing some customization of them, you should be starting with Mainconcept MPEG-2 on one of the DVD Architect NTSC templates.

Hey, one problem could be if you've selected 24p. I think you need to select 23.976 with 3:2 pulldown to conform to the DVD spec. DVDA will definately rerender if you're not giving it a spec-compliant file. Here's way more than you ever wanted to know about the DVD spec.

[Jamie Hellmich]

Seth, you nailed it! Framerate. I was not using the framerate with pulldown.

One note though, the linked document you provided specifies "23,976 fps with 3:2 pulldown" (cut and pasted from the document), and the Vegas selection reads "23.976 + 2-3 pulldown". I know the comma is a typo, but I'm not sure of the 3:2 versus 2-3 difference.

I also notice when the framerate with pulldown is selected in the dialog box, the field order sets hard (grays out) to progressive. I was selecting 23.976 (no pulldown), then selecting progressive field order...wrong method it appears. I would assume the same applies to 30p, and the high definition files as well, paying attention to the default formats. I've still much to learn.

Part of my "problem" may lay in the fact that I use my pc and a PS3 for review of the files. That PS3 will play darn near any file format (even written as a data disk) I throw in it, and very well. And, I was using other authoring software for test DVD disks, as it did not recompress the files like DVDA did.

Now I know why DVDA wanted to recompress, and perhaps why the disk authored by "other" stuttered on my mom's player the other night and didn't look very good.

It's still a little puzzling though, that when just changing the quality setting to "good", DVDA didn't need to recompress. That was the only change to the template.

Believe me, I need all the info I can get. And will also check out Edward's newsletters, as well as continue foraging through these forums.

A new V1u is in hand now and I want to take full advantage of it, and take some steps forward in my "filming and production".

This progressive shooting and post is a little different animal. Now if I could just figure out.....

Thanks so much for your answer Seth.