-
Avid/Sorenson issues
I’ve authored DVD after DVD with no problems, but I’ve recently run into one. I’m working in Avid with video at DV25 411, and graphics at 1:1 (in the same timeline). Since I need the graphics to stay at 1:1 to match as close as possible to the stills in my menu, I mixed down my video layers in 1:1. When I export the file (reference or self-contained movie) and try to squeeze in Sorenson, I get jitter in my video, especially during white flashes. I know it’s not an interlacing issue because I’ve tried all possible interlacing options in Avid and Sorenson. Anyone have any insight? This was never an issue when I was working only with DV 25.
-
8 Replies
-
check or change the field order and try again. See if the problem goes away.
-Alex
-
Thanks for the quick response!
I exported the video as an uncompressed Quicktime Movie, Upper field first, from Avid. Then, I Squeezed it in sorenson as upper field first (Auto remove interlacing off) and brought it into Encore. The video clip looks crisp when I preview it in Encore, but when I burn the DVD and view the disc on a set-top player, that’s when the artifacting/jitteryness shows up. I would assume it isn’t a field order issue because I’ve got text at the top of the video that is super crisp around the edges.
-
Try a test of say five minutes from the same timeline, reverse the fields, and burn the DVD with nothing else, and see if it goes away. Will take just a few minutes, and might solve your issue.
-Alex
-
NTSC DV is lower field first, so try re-exporting with lower. If you’re on the same machine, save some time and drive space by exporting a QT reference, then encode from that in Sorenson.
-
Usually I encode with a QT Ref – that’s the first thing I did with these clips – I brought the refs into Squeeze and encoded them with the correct field order. All field orders were unsuccessful, so I exported a clip as a self-contained quicktime movie, because Avid gives you more options, including compression type, field order, etc. Still looks like I’m getting banding – and jumpy playback. The next thing I’m going to try is different settings in that QT movie export dialogue box in avid – perhaps trying different types of compression could solve the issue.
Thanks again, everyone, for helping me troubleshoot.
-Tom
-
Here’s a still out of Sorenson that represents the issue I’m having. Squeeze doesn’t normally represent the final product very well, but in this case it does; the areas with more defined lines look choppy during quick movement when I play back the DVD (My A/V combined bitrate is 8500k). This is odd, right?
-
Okay, I’m having another thought here. NTSC DV and NTSC MPEG-2 for DVD share the same pixel size – 720×480, whereas 1:1 Avid is D1 height – 720×486.
You’ve probably never had any issues like this before due to that similarity. Since the mixdown was done to 1:1 in Avid, I’d assume its pixel size to be D1 – unless in your general settings > effect aperture you have it set for DV 480. Since a mixdown is an effect it’s possible that the aperture setting was adhered to and your video was scaled up to D1 height, stretching the DV 480 interlaced fields and causing all kinds of havoc. I’ve had similar results in AE when i’ve forgotten to adjust my comp size and rendered out.
Of course if Avid simply adds the extra 4 black lines at the top and 2 at the bottom (or 2top 4bot – don’t want 3 top and bottom or the field order is changed) then my theory would be wrong.
I’m not sure what the solution is, but it may be a point in the right direction. -
I had a simular issue with 1:1 titles and DV25 video but Avid fixed the bug. However it does require that you check the “Use Avid DV codec” box under options. Hope that helps.
MArk
Reply to this Discussion! Login or Sign Up