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Level 1

87 points

Adding Transitions freezes and stutters playback in Preview.

I'm posting this as a new issue. Since I've narrowed down my "stuttering/freezing on playback" problem while in Preview/Edit mode.

This begins to happen as SOON as I add a transition. Whether I add it automatically, or manually.

The clips play fine without transitions in the project and the Event window. These are clips from a Kodak Zi6, I believe shot HD at 60fps, and I'm using NTSC 30fps to create the project. When I "get info" on my clips, the codecs listed are H.264 and AAC, dimensions 1280x720.

When the Movie Project is exported & viewed in QuickTime, it plays smoothly.

Any ideas are greatly appreciated, as I'd like to preview my work as I go!
This movie is LESS than one minute long!

IMac 3.06 4GG, 1TB, Mac OS X (10.5.6), Kodak Zi6, Casio EXZ850

Posted on Mar 24, 2009 7:56 AM

31 replies

JBK Author

Level 1

87 points

Mar 25, 2009 7:07 AM in response to tjworld

tjworld,
I just checked the file (for my Kodak zi6) size...for a 9 second clip, before conversion was 10.1mb, after conversion (using your method) was 48.4mb.
This is far superior to the MPEG Streamclip method, which took a 22 second file from 33mb to a whopping 415mb converted!

This is GENIUS, I can do this without additional software, and not bloat my hard drive with duplicate gigantic files!

p.s. I mentioned above that it "changed" the file to a QuickTime movie, forgive me, the Kodak Zi6 already was a QuickTime .mov file, just changed the Codecs from H.264 to the AIC.

tjworld

Level 1

14 points

Mar 25, 2009 8:40 AM in response to JBK

At last a workaround that works..!!

as far as I can tell you just need to convert a section of each file in the event window - the conversion works on the whole event clip even if you just select a small portion

so, if your event contained say 10 separate .mov files then convert each one. Once you've done this before you start work editing everything is smooth.

I think the apple iMovie should auto do this as you import the files but clearly it does NOT.

keep me informed - I'm editing tomorrow and will try it more but I believe this is an easy workaround that has solved all the problems.

If you find this too then lets post a new thread - I think theres a lot of frustrated users out there who would appreciate it!

I hope apple fixes the problem as well but for now this gets us working smoothly. Fingers crossed it stays working OK - it feels like it should once you have everything in apple codec AIC. Remember you'll know by checking the "clip" of any sections in the project window and applying the "Convert" if needed.

Hope this saves us some frustrating time....

keep me posted if you find any problems/ degredation of footage etc - should be OK though.

good luck - I will do more tests tomorrow.

thanks
tj

JBK Author

Level 1

87 points

Mar 25, 2009 10:11 AM in response to tjworld

tjworld,
Since you're the GENIUS that came up with a SIMPLE solution, I'll give you the honor of creating a new thread, so we can help others!

Maybe it could be titled "MPEG Streamclip ALTERNATIVE!" Clearly easier than additional software!!!!!

tjworld

Level 1

14 points

Mar 25, 2009 11:11 AM in response to JBK

Thanks - I'll draft something later then

keep me posted in case we find some glaring error!

tj

JBK Author

Level 1

87 points

Mar 25, 2009 11:50 AM in response to tjworld

tj,
Do you see any change in the clarity of your clips after using the "conversion" in Imovie? Mine appear much less "sharp." When I used the MPEG Streamclip, I was able to dial the quality up to 100%, but there's no adjustment for quality in the simple conversion in IMovie....so, I have a feeling that we're losing quality with the Apple AIC conversion, especially, since the file size is considerably smaller than the Streamclip method.

JBK Author

Level 1

87 points

Mar 25, 2009 12:40 PM in response to JBK

I'm sorry that this post is getting carried away, it's just such trial & error...

Actually what I meant to say, is the files that are encoded "AIC" whether through Apple Imovie or Streamclip are definitely less "sharp." Makes no difference as to the 100% "quality" slider, I thought had an effect.

Anything encoded H.264, whether my original Zi6 footage (60fps HD 1280x720) or Streamclip to Mpeg, keeping the H.264, is MUCH sharper.

Only problem...is the H.264 causes it to stutter, as SOON as transitions are applied. So....do I live with fuzziness, or stutter? Which I could have clear & smooth.

Mar 25, 2009 1:19 PM in response to JBK

AIC should be clearer than h.264. If it is not, you might try deinterlacing with Streamclip as you convert to AIC.

JBK Author

Level 1

87 points

Mar 25, 2009 1:39 PM in response to AppleMan1958

Thank you. I'm not very good at figuring out Streamclip's settings.

Should I choose: "Export to Quicktime", AIC for Compression, at 100% quality using slider, then "deinterlace video"?

Are there any other settings I have to alter??
Thank you so much for helping me.

tjworld

Level 1

14 points

Mar 25, 2009 1:42 PM in response to AppleMan1958

phew - The footage Im editing is inside a studio so no natural light - I have not noticed any loss of sharpness. I only recorded at 30fps anyway but I cannot see any difference yet with conversion. maybe need to run some hard comparison tests with same footage...? did you export final edit to quicktime?

iMovie forces you to convert the files for special effects anyway...Hmmm.

I would like to hear from others their feeling on this Workaround. Its impossible to edit properly with stuttering footage as you loose the rhythm of the piece so I would rather have it working smoothly like this...

anyone else tried this out and found quality loss?

the program should just work without any of this! grrrrr

JBK Author

Level 1

87 points

Mar 25, 2009 1:55 PM in response to AppleMan1958

I just compared....and unless I'm missing something other than Export to QT, 100%, AIC, Deinterlace, the quality is DEFINITELY sharper with my original H.264 QT .mov file. And drastically smaller as well. Too bad it stutters with transitions.

Welcome to more ideas!

Mar 25, 2009 1:58 PM in response to JBK

Don't know if this helps but I have taken out all transitions and 15 minutes of Caribbean Cruise plays without a stutter or freeze in sight at 25fps.

tjworld

Level 1

14 points

Mar 27, 2009 5:24 AM in response to JBK

At Last! Just installed the iMovie update - hope it cures the issues we're all having..

will try later

tj

tjworld

Level 1

14 points

Mar 27, 2009 5:41 AM in response to oldmovieguy

Has apple fixed our problems?? I just added clips from the Zi6 without conversion and they are working smoothly!!!! even threw in a few fade to blacks/transitions and still working - fingers crossed its working .....

JBK - hows it working for you?

anybody else?

JBK Author

Level 1

87 points

Mar 27, 2009 7:01 AM in response to tjworld

Hi tj,
I was hopeful! I started a new project with the original footage from the zi6, and as SOON as I added the transitions, it stuttered & froze.
It cannot handle the more "complicated" transitions. It can do the simple ones..like "fade to black", but chokes on anything more "involved."
Oh well...would have been nice to have a fix from Apple with the update!

tjworld

Level 1

14 points

Mar 27, 2009 9:31 AM in response to JBK

I'm working on my one now.. and its better...but still not 100% - may still try my "Convert to AIC" workaround. I've been doing green screen filming which works but is difficult to get the green screen to start at the same time as the underneath footage. It also seems to "trip up" iMovie still. May try editing small sections, exporting and then assembling "these finished pieces" in a second project.

I so want it all to work seamlessly! I guess Apple still has work to do! ..but it IS closer.

tj

Adding Transitions freezes and stutters playback in Preview.