5 Replies Latest reply: Feb 4, 2013 5:25 PM by Dan Thomas (DAGWare)
Dan Thomas (DAGWare) Level 1 Level 1 (105 points)

I have some videos which were converted to 30fps from a lower frame count. It was obviously a simple conversion that duplicated frames as needed.

 

The problem is, when I use these videos for slow motion, the duplicated frames cause the slow motion to "pause". In order to fix this, I have to remove the duplicated frames (obviously I don't care about sound, and I don't care about time sync). Once the duplicated frames are removed, the slow motion is nice and smooth.

 

In the past, I've always done this with very short clips, so I can do it manually. I open the video in QTP, advance one frame at a time, and when I see a duplicate, I delete it. Since there's always a pattern, depending on what the lower frame rate was, this can be done reasonably quickly, for very small clips. But it's obviously a tedious process.

 

I was wondering a few things:

 

1) Can Compressor 4 fix this issue for me? I've tried a few things in Compressor, but no help yet. I'm just a relative newbie, so that's not surprising.

 

2) Are there any other utilities that might help? Something that removes duplicate frames, for example?

 

3) These clips were already converted when I received them. However, in the future, when I convert a lower fps to 30fps for the purposes of doing slow motion, how should I do this in Compressor so as to have smooth slow motion at 30fps? Again, I don't care about audio.

 

I've done a few days worth of searching, but I still havent found the answers. Any help will be appreciated.

 

Thanks!

 

Dan


iMac (21.5-inch, Late 2012), OS X Mountain Lion (10.8.2)
  • 1. Re: Can Compressor 4 remove duplicate frames?
    Russ H Level 6 Level 6 (14,270 points)

    So do we take it that the original clips were 15 fps?

     

    Russ

  • 2. Re: Can Compressor 4 remove duplicate frames?
    Dan Thomas (DAGWare) Level 1 Level 1 (105 points)

    Some clips are different than others, but most of them seem to be converted from 25 to 30, since every 5th frame is a dup (if I've got my math right).

     

    Dan

  • 3. Re: Can Compressor 4 remove duplicate frames?
    Russ H Level 6 Level 6 (14,270 points)

    Turn on Frame Controls and try Reverse Telecine (in the De-interlace box) on a test clip. Dependig on how they got to 30 (29.97?), it might get rid of the extra frame.

     

    BTW, how much do you want to slow this down?

     

    Compressor can do slo–mo (also in Frame Controls), but FCP (and Motion(does a pretty good job, depending on the content, and gives several options.

     

    Russ

  • 4. Re: Can Compressor 4 remove duplicate frames?
    Dan Thomas (DAGWare) Level 1 Level 1 (105 points)

    Thanks. I'll try that.

     

    Generally, I want to slow them down to 1/4 speed. Depends on the clip, though.

     

    Yes, I've been experimenting with the differences between doing it in FCP and Compressor. Sometimes FCP is fine, sometimes I need to use Compessor. I'm sure I'll learn as I go on.

     

    Thanks for the help. I'll report back on whether this solves the issue or not.

     

    Dan

  • 5. Re: Can Compressor 4 remove duplicate frames?
    Dan Thomas (DAGWare) Level 1 Level 1 (105 points)

    The Reverse Telecine didn't remove the extra frames. Who knows - maybe the frames aren't exact duplicates, although for the most part, they look it to the naked eye, which I realize doesn't mean much.

     

    Oh well, doing it by hand isn't the end of the world. I've probably spent more time trying to figure out an automatic method, than it would have taken to do it by hand. But of course, I'm sure I'm not the only one who's ever done that... 

     

    Thanks for trying. As I've been searching for help on other things, it's amazing how many times one of your posts helps. So you've helped me plenty, for which I thank you.

     

    Dan