Ulead's AVI files frame rate is not to NTSC Specification

[Lamont Cranston]

If you are capturing video with AVI_IO or VirtuaDub and are planning on editing with Ulead's Media Studio Pro or DVD MovieFactory and frameserving the captured and edited AVI files to TMPGEnc you may run into problems. The frame rate in Ulead's NTSC AVI files does no meet the NTSC spec. The rate and scale for a NTSC AVI file is Rate = 30000 and Scale = 1001. Ulead uses a Rate = 2997 and Scale = 100. Close but not correct. The slight difference only amounts to a ~1 frame loss per hour and is insignificant by itself. The difference does cause problems when you try to combine MSP AVI edited files with AVI files from other sources outside of MSP. If you frameserve with VirtualDub it reject the files because of the difference in frame rate.

[Spicuzza]

Lamont Cranston,

I've also noticed that Ulead defaults to a frame rate of 29.97 frames per second. I'm not fully understanding your post. Could you help me understand why the default is 29.97 and not 30 as I believe that is what your saying it should be in your post.

Looking forward to your answer.

Thank you,

Gary

[Lamont Cranston]

When I ran into the incompatability problem and I found out that in the NTSC AVI file header the DataRate and TimeScale are specified. The frame rate = data rate/time scale. For NTSC, from what I have netted out, the data rate = 30000 abd the time scale = 1001 which is a frame rate of 29.97003 not 29.97000.

I believe the 29.97 (drop frame) vs 30 is based on American TV.