import quality in Imovie HD

Discussion in 'Digital Video' started by scanline, Apr 1, 2009.

  1. scanline macrumors newbie

    Mar 9, 2009
    I'm trying to edit some dvd clips together for a demo reel but I'm having trouble getting decent quality in Imovie HD. I'm converting the vob's into DV clips with mpeg streamclip and the apple mpeg2 component. This seems to maintain the most quality that I've found so far. The problem I am having is when I import these clips into Imovie, the low end has significant clamping and compression artifacts. I was under the impression Imovie used DV as its underlying format. Why would it be recompressing the clips and is there any way around it? I tried importing the same clip in a trial version of Premiere and it looks wonderful. Import into Imovie, crap. It seems like imovie should be able to handle it and I'm just not getting the correct order or pressing the correct buttons or something. My project is set to full 1920. Any help or insight is greatly appreciated!
  2. huntercr macrumors 65816

    Jun 6, 2006
    Yes, your converting it to DV is correct.

    Pardon my ignorance, but what is clamping?

    And what do you mean your project is set to "1920". Are you saying it's 1080i? Your DV is only SD resolution, so not sure why you're doing that if you are.

    You should not be seeing any compression artifacts.
  3. scanline thread starter macrumors newbie

    Mar 9, 2009
    Sorry, yes, I meant 1080i. The higher of the two options in iMovie for the project resolution (1920 being the horizontal resolution). By clamping, I mean I'm losing detail in the lower color values. Instead of a nice smooth change in color values, they harsh and change abrubtly and don't have the detail that is in the original movie.

    I'll try the lower quality setting in Imovie. Also, iMovie seems to want to scale everything up to fit the screen by default. Maybe I have to pad the movie size to fit into 16:9 first?
  4. scanline thread starter macrumors newbie

    Mar 9, 2009
    I'm still not having any luck. Has anybody successfully edited dvd footage in iMovie with good quality? Also, I guess iMovie doesn't have a project resolution, you can just select one when you import movies, but iMovie says that has no effect for DV clips being imported. Which leads me to believe it is supposed to be importing the DV clip as-is. Perhaps iMovie lacks the mpeg2 support necessary to view and export these clips at full quality? I don't know, I'm grasping at straws here and I don't fully understand all the pieces of the video editing puzzle. Does anybody think there is a way to do this in iMovie or am I going to have to bite the bullet and get Premiere or FCE?
  5. scanline thread starter macrumors newbie

    Mar 9, 2009
  6. huntercr macrumors 65816

    Jun 6, 2006
    When you converted it to DV, you should specify that you want 16:9 DV, Also... why are you using 1080i for a DVD? You're upscaling considerably.

    If you are seeing your color values diminish, you could try converting the MPEG2 files into AIC format and see if that helps.
  7. scanline thread starter macrumors newbie

    Mar 9, 2009
    Further research seems to point to an inherent problem with iMovie '09 and DV footage. It doesn't matter what options I pick, iMovie does the same thing no matter what with DV footage, which is throw away half of your data.

    I found this thread on the apple support forums:

    longwinded and quite the process of discovery, but the short answer seems to be use iMovie '06 or, use iMovie '09 to edit and export the xml data into FCE or, convert to AIC and deal with the changes in color. Further testing to commence this evening....
  8. huntercr macrumors 65816

    Jun 6, 2006
    Very interesting. I'd never heard this. That's sad to read because its a major step back in quality.
  9. kidthomson macrumors newbie

    Jun 30, 2009
    Scaling issues as well.

    I'm having the same issue. I'm trying to create a movie that has both HD and SD components. And every time I import something that's not HD it scales it up so it's blurry and unwatchable.

    Is there a workaround for this??

    I would really appreciate any advice you guys might have.


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