VideoHelp Forum
+ Reply to Thread
Results 1 to 13 of 13

Thread: Merging files

Thread
  1. I have looked but almost always "merge" has been synonymous with cut paste and join. Is it possible to truly merge two videos frame by frame. Ie video 1 fame 1 then video 2 frame 1 and so on. Short of frame by frame cut and paste.
    Quote Quote  
  2. Member
    Join Date: Sep 2007
    Location: Canada
    Search Comp PM
    Not without re-encoding, but you can use interleave() in avisynth

    interleave(video1, video2) would return video1 frame 0, video2 frame 0, video1 frame 1, video2 frame 1, etc...



    PS. An end to end join in video terminology is normally called "appending" or "concatenating"
    Quote Quote  
  3. Thank you for your quick response. My goal is to simulate high speed recording. My thought is append (correct?) the same video several times. Thus turning 30fps effectively into 90fps. Then slowing down the fully appended clip by to 33%. Thus slo mo without degradation of quality. Is this a silly way to do it?
    Quote Quote  
  4. aBigMeanie aedipuss's Avatar
    Join Date: Oct 2005
    Location: 666th portal
    Search Comp PM
    appending the same video to itself will only result in replaying the same video at normal speed several times.
    --
    "a lot of people are better dead" - prisoner KSC2-303
    Quote Quote  
  5. Member
    Join Date: Sep 2007
    Location: Canada
    Search Comp PM
    Originally Posted by drtbray View Post
    Thank you for your quick response. My goal is to simulate high speed recording. My thought is append (correct?) the same video several times. Thus turning 30fps effectively into 90fps. Then slowing down the fully appended clip by to 33%. Thus slo mo without degradation of quality. Is this a silly way to do it?

    No that won't give the desired result

    It sounds like you want a slow motion video? But without actually shooting a higher FPS ?

    You have to either play a slower fps, or interpolate new frames (as if you shot a higher FPS in the first place) either by duplicating, blending or synthesizing new frames . There are many disadvantages to either of these methods - the best way is obviously shooting a higher FPS with a better camera
    Quote Quote  
  6. Yes. I've done that with Magix and power director. Too much degradation. Sorry I really am a novice. But if I had 3 frames exactly alike at 30 fps, the total time would be 3x. Played faster would be the same as th original yet slower. As long as the speed was not 3x. I was accurate above when I said slow down final clip. It should be sped up.
    Quote Quote  
  7. Member
    Join Date: Sep 2007
    Location: Canada
    Search Comp PM
    Clarify:

    Did you want something like a timelapse, where only every "nth" frames are displayed (so the video looks very fast)

    Or did you want slow motion video? (video looks smooth and slow)
    Quote Quote  
  8. Again. I think terms are where I am confused. Append may not be correct. I'm not putting two together end to end but inserting the same frames out of phase. To result in v1f1v2f1v1f2v2f2......
    Quote Quote  
  9. Smooth but slow.
    Quote Quote  
  10. Member
    Join Date: Sep 2007
    Location: Canada
    Search Comp PM
    Ok - Slow motion means you have more frames, but usually played back at the same FPS

    So if we have a 1 second, 30 fps clip. There are 30 frames. All those frames are displayed in 1 second.

    If we make it 3x slow motion, the same clip now has 90 frames, but still plays 30fps. Thus the duration is now 3 seconds long

    The problem is how to generate those "extra frames" without using a more expensive camera


    There are 3 principle methods:
    1) duplicating frames - choppy
    2) blending frames - choppy & blurry
    3) motion interpolated frames - smoothest but prone to edge morphing artifacts

    There are pros/cons to each approach

    This has been discussed several times before. Read this thread, and download the examples from vimeo and the attached video for illustration
    http://forum.videohelp.com/threads/340910-looking-for-s-w-that-can-recreate-an-MP4-fil...peed?p=2121826
    Quote Quote  
  11. Thank you. My thought was if you could merge the same clip out of phase then you would be duplicating frames. I'll read the forum on that. Was your suggestion of interleve with avisynth not just that?
    Quote Quote  
  12. Member
    Join Date: Sep 2007
    Location: Canada
    Search Comp PM
    Originally Posted by drtbray View Post
    Thank you. My thought was if you could merge the same clip out of phase then you would be duplicating frames. I'll read the forum on that. Was your suggestion of interleve with avisynth not just that?
    No, Interleave(video1, video2, video3) where video1=video2=video3 (ie. it's the same clip) and then slowing it down using AssumeFPS(30) will give the same results as method above 1) duplicating frames . It will give choppy result

    The problem is how to get those "out of phase" frames. In other words, how do you generate all those extra "in between" frames? Or 3 different clips
    Quote Quote  
  13. Originally Posted by drtbray View Post
    My thought was if you could merge the same clip out of phase then you would be duplicating frames.
    What do you mean out of phase? All you're doing by Interleaving the same video three times is duplicating each frame 3 times. Ie

    Interleave(vid, vid, vid)

    Is the same as:

    SelectEvery(1,0,0,0)

    or:

    ChangeFPS(3x) #where 3x is three times the original frame rate

    It will give you slow but jerky video. I take it what you're looking for is something like this:

    http://www.youtube.com/watch?v=71nURVXXeaM
    http://www.youtube.com/watch?v=zaPKgSSkYm8

    You either have to shoot with a high frame rate camera (they go up to millions of frames per second and costs millions of dollars, there are a lot of consumer level cameras that shoot 120 to 600 fps) then play it back more slowly, or you can try using motion interpolation software which looks at motions in the frame and tries to generate in between frames based on that motion.

    http://forum.videohelp.com/threads/344802-Youtube-videos-with-horrible-frame-rate?p=21...=1#post2150528
    Last edited by jagabo; 13th Apr 2012 at 17:39.
    Quote Quote  



Similar Threads