Import iphone 4K 30fps movie clip the blender become extrem low

The steps:

  1. Movie Clip ,Open 1 moive capture from iphone 4K,240Frames total only ,30FPS,only 8seconds.
  2. Click Prefetch, Play the movie FPS 24(Its fine)
    2.Track motion the moive,Play the movie FPS 24(Its fine)
    3.Set the floor,etc.
  3. When Click “Setup as Background” and "Setup tracking scene " in the 3D Viewpoint,Press “0” The camera perspective
    Then the movie clip become extrem slow only FPS 2~3,almost can not move ahead. Even you can not pull the timeline because the blender will no respond.
    Only in User Perspective recover FPS 24, but you can not see the movie clip as background its hard to make the animation now.

What can I do to fix the issue,extrem slow.

Any one can save me ?It waste lots of time and almost cannot composite the 3D models at all.
Increase the blender system DRAM to 16GB (AMD 8Core,Nv 1070) even the Proxy 25% quality. But the play FPS only several frame.

When set moive clip as background it become even more slower. Almost can not drag the timeline ,super lag.


Look into proxying your images prior to adding to the viewport. Resize your sequence in another Blender session via the Sequence editor.

Your issue is most likely the drive IO or at least it is one of the issues you have. In that case you can try creating a RAM drive and try loading your sequence from a RAM drive, but that means that you need to have alot of free RAM.

Yeah, resize those videos before putting them into blender. They are so blurry anyway, you aren’t even using that resolution.

I’m using the 1080P taken from iphone only 45MB file now but still the same slow. Dont understand why blender is hard to deal the video.
I create the RAMDISK and put the clip in the disk.The FPS still only 3~4.
Video Sequencer to resize how much? 720P?

If you just need to preview what you are doing, just render an Opengl sequence of the viewport and use Djv or Mr Viewer to do a realtime playback.

Im doing the motion track and composite the 3D model in the movie clip.Not understand the rendering Opengl sequence?

how much ram do you have? and how long is the sequence?

If blender can’t cache the frames, it will run pretty slow…

64GB Mem, Sequence only few minutes usually 3~5min. When set moive clip as background then will changed extrem slowly even in Cache.