Mpeg2 render issues

Udi wrote on 7/15/2008, 4:41 AM

Hey

I'm trying to export a DVD out of an HDV M2T project, shot on the Z1, on Vegas pro 8. When I render the timeline to Mpeg2, the resulting image seems higher in contrast compared to the original. Here's what I mean:
http://img225.imageshack.us/my.php?image=mpegrenderdy4.jpg

The change isn't dramatic, but noticeable - the upper image is higher in both saturation and contrast.

My Mpeg render specs:
Video rendering quality: Best
Output type: DVD
720-576 px
16:9
I-frames 12 B-frames 2
progressive scan
video quality 31 (highest)

I used ITU-R Rec. 709 (1990) on Transfer, Matrix coefficients and Color primaries in the Advanced Video tab.

Does anyone have an idea why this happens?

Comments

owlsroost wrote on 7/15/2008, 3:56 PM

It should be ITU-R Rec. 624-4 on Transfer, Matrix coefficients and Color primaries in the Advanced Video tab for SD i.e as per the standard DVD templates.

The Rec 709 colour space is used for HD, Rec 624-4 is used for SD normally.

(AFAIK Vegas uses computer RGB colour space internally, so all the source video will be decoded to this before rendering, then converted by the output codec into whatever colour space is required for that format, so input and output colour spaces don't have to match)

Tony

GlennChan wrote on 7/15/2008, 4:07 PM

Some guesses:

1- Do you have any video preview FX? If you render something out and bring it back in, you'll be looking at video preview FX applied twice.

2- Article on color spaces in Vegas 8:
http://www.glennchan.info/articles/vegas/v8color/v8color.htm