Cutting avi leads to distorted video

[headless chicken]

I'm new to Mac OS, and so I know next to nothing about video editing on OS X. I have Quicktime Pro, MPEG Streamclip, Avidemux, and Cinematize 2 all installed, but I can't seem to acheive the results I want.

I ripped a chapter from a DVD with Handbrake and now want to trim that avi into an even smaller selection to upload on youtube. I used Quicktime Pro to trim and resave the new file (although it saves as mov, I think that does not matter because mov and avi is only a container). Anyway, although these new files work fine on my Intel Mac, they playback very strangely upon startup once uploaded to youtube.

To see what I mean, check out:
http://www.youtube.com/watch?v=KQz4zorM1Sk
and
http://www.youtube.com/watch?v=ex_fhd6O9jc

(I ripped the first clip, but the second was already an avi file that I trimmed down)

Could this be an issue with keyframes and correctly reindexing? On a PC I would use VirtualDub and TMPGEnc. I'm lost though, and have no idea what's causing the first few seconds of the video to distort.

I'd appreciate it if some more experienced Mac folks could chime in.

[rumplestiltskin]

The start of each of the videos shows what you would expect when cutting between keyframes; you get just the changes to the keyframe until the next keyframe comes along.

I do see the first video as 4:3 with the second letterboxed. Is this what you intended?

[headless chicken]

The two samples are from 2 different sources. I believe the aspect ratio for the second clip should actually be 4:3, but I don't know how to resample it on a Mac. I could use VisualHub, but that would degrade the clip by reencoding the whole thing.

How do I fix this issue of cutting between keyframes? I've used Quicktime Pro before to cut wmv content packaged in a mov container (which was then converted to avi to upload to youtube), and I had no problems with the beginning of the clips when played on youtube.

[rumplestiltskin]

In MPEG Streamclip, before you set your "I" point, use the "Go to Keyframe" command from the Edit menu. Repeat with the "O" point. This should set the keyframes properly. (It may not even be necessary to end at a keyframe.) Then "save as".

If the ratio comes out bad, you can always do an "Export to AVI..." and set the proper ratio there.

Let us know how it goes.

[headless chicken]

That seems to have done the trick. There's a slight clicking noise in the new youtube video of the identical clip, but the video is flawless. Thanks rumplestiltskin.

Oddly enough, I couldn't use the avi I ripped from the original source because it wouldn't register in MPEG Streamclip. There was no video, and the audio only went until 1:50. However, the clips I created by trimming the avi with Quicktime Pro *did* register in Streamedit, although I don't understand why.

What's unfortunate is that I can't use the VOB on the DVD directly in Streamedit because the DVD seems to be encrypted. That's the same reason why I can't open it in Cinematize 2 either. Handbrake does allow me to rip from the DVD, but only by chapter. I wish there was another utility that would allow me to rip just selected portions. It would eliminate the need to cut the file in Quicktime, import to Streamedit and then sort out keyframes.

[rumplestiltskin]

Try Mac the Ripper to put the VIDEO_TS folder on your HD.

I also keep a copy of MPEG Streamclip set to open in Rosetta simply because there are a few codecs that work in Rosetta but are not yet fully compatible with the Intel/OSX version of QT. Some AVI's that won't open properly in the native version will work in the Rosetta version.

Also ffmpegX is handy to have around for some AVIs that MPEG Streamclip (or even QT Player) won't handle at all. It also produces excellent quality.

Let us know how it goes.