853x480 results in black bars

ojpt wrote on 12/15/2009, 2:32 PM
When I playback my DVD in InterVideo WinDVD there are small black bars to the left and right of the frame.

My workflow: The show is 2 hrs long. I'm using VMS Platinum Pro 9.0b; source footage is Panasonic SD-9 1920x1080 at 23.976p. I transcoded the footage to 853x480 23.976p uncompressed (no resampling; deinterlace none). I then burned a 29.97 widescreen DVD using DVD Archictect Studio 4.5. MPEG-2 compression was done in DVDA (in order to get the file size correct).

The black bars are present in the DVD Architect Studio preview window -- leading me to believe that 853x480 was a bad choice for image dimensions. However, playback on my HD plasma screen and DVD player looked fine, no black bars on the sides and the image quality is excellent.

I suppose I should test some differnt SD frame sizes myself. Anyone else have workflow suggestions when taking full HD down to SD widescreen for the purpose of making a DVD?

As a follow up: In VMS, how do I make a SD 16:9 anamorphic uncompressed master that DVDA Studio recognizes as a widescreen program?


thanks!

Comments

musicvid10 wrote on 12/15/2009, 4:20 PM
That is because NTSC Widescreen is not exactly 16x9 aspect.

NTSC Widescreen is 720x480 at 1.21212 PAR
720 x 1.21212 = ~873

So if you must use square pixels, make it 873x480. That will fill in the black bars.
ojpt wrote on 12/16/2009, 11:43 AM
that explains a lot! thanks for your help.

Based on your suggestion I found that DVDA will fill the entire screen using 874x480 square pixel as a source. There is no cropping and no letterbox (at least in the preview). Problem solved.

I also found that the MPEG-2 Widescreen DVD Architect template in VMS rendered a compliant image size (720x480 anamorphic) by cropping the original 1920x1080 frame slightly.

Finally, I could not produce an uncompressed anamorphic render that DVDA Studio recognizes as widescreen.
musicvid10 wrote on 12/16/2009, 12:21 PM
I also found that the MPEG-2 Widescreen DVD Architect template in VMS rendered a compliant image size (720x480 anamorphic) by cropping the original 1920x1080 frame slightly.

That is correct. 1920 x 1080 (1.0 PAR) is exactly 16:9 SAR. To fit NTSC Widescreen dimensions, it would crop the top and bottom slightly. The alternative is to stretch the image aspect horizontally.

Finally, I could not produce an uncompressed anamorphic render that DVDA Studio recognizes as widescreen.

Uncompressed AVI VFW is square pixels.
Uncompressed takes up a lot of disc space, and there are other intermediate options that are visually lossless. However, since you are starting with 1.0 PAR, you may want to choose to stick with it.