DVDA won't transcode 24P MPEG2 to AVC

Richard V. wrote on 4/18/2012, 8:27 PM

I have been using Vegas and DVDA for years almost always with 60i source material. For simplicity I usually render from Vegas as HDV (which requires no recompression on 60i material). Then I use DVDA to create a Blu-ray project with menus, and prepare this as an AVC iso file. Finally I copy the project, change its properties to DVD, and prepare it as a DVD folder. This simplifies the workflow and has produced excellent results.

Occasionally I have used 24P HDV for reasons of low-light capability. Right now I have a 24P movie of just under 2 hours. Vegas refused to smart-render either with the "HDV 1080-24P" template or the "Blu-ray 1440 x 1080 25Mbps video stream" template, so I used the latter and rendered the project without smart rendering (although it didn't take too long). The file was some 27GB in size but I counted on being able to recompress from DVDA into a smaller AVC file. However, when I tried to prepare the Blu-ray AVC file from DVDA, it insisted on leaving the MPEG2 file unchanged, which is of course too large for a 25GB disc. No matter what bitrate I selected for the AVC, it would only affect the projected size of the menus and not the main timeline. I went ahead with the preparation anyway, hoping that it was just the file size prediction that was incorrect, but after a short rendering session the system produced an ISO image of more than 27GB.

My question is, what box have I failed to check, or what procedure should I follow to get DVDA to render the menus plus timeline into a 24P AVC file?

Thanks,

Richard Vaughan

Comments

Steve Mann wrote on 4/18/2012, 9:25 PM

You do not want DVDA to re-encode your files. Anytime DVDA re-encodes the file, you did something wrong in Vegas. (And you compromise the quality a bit).

Go back into Vegas and re-encode the HDV file with a lower bitrate to get to the target size.

Richard V. wrote on 4/20/2012, 7:49 PM

I certainly don't want two transcodes. But with other files I have smart-rendered from Vegas with no recompression required, making a .m2t file that DVDA can render either for DVD or for Blu-ray. So each finished product involves just one recompression, and the process of preparing output in multiple formats is very simple. Also, I usually use AVC for the Blu-ray and DVDA seems to do an excellent job with this, even though the only available control is the bitrate.

The problems with this particular 24P project are (a) that I couldn't smart-render out of Vegas (so I did the next best thing, using a format that matched the source material) and (b) that DVDA refused to convert the MPEG-2 file to AVC. It is this second problem that is most puzzling. DVDA made DVD's from the same file just fine. Of course I can go back to Vegas and re-render for Blu-ray and that's what I'll probably do, but I'd also like to know what causes DVDA not to want to render the file as AVC.

Thanks,

Richard V.