Synchronisation between Video and UI/Image editor I am a  fresh Blender user. I started collecting training videos and some of them are very explanatory indeed. So I guessed, following their instructions I could manage. The problem I describe here is a problem I have with all the videos I shot with my Panasonic Camcorder  HC-VX870.

In this video, wanted to blur the ship floating on the river Seine.

System imformation :
Computer ASUS Desktop PC P30AD
Processor 4 Intel Core i3-4160 CPU @ 3,60 Ghz
Memory : 3914 MB
OS : Ubuntu 16.04.2 LTS

Specs of the video :
Duration :  1 minute 24 seconds
Container : Quicktime

Video :
Dimensions : 3840 x 2160
Codec : H.264 (High profile)
Frame rate : 25 fps
Bit rate : 61128 kbps

Audio :
Codec : MPEG4-AAC
Channels : Stereo
Sample rate : 48000 Hz
Bit rate : 256 kbps

Media details
Demuxer : lavfpref

Let us now take a look at  the process itself.

Step 1 : I add the video. It appears in the upper-right side window. Everything works fine.

Step 2 :  I open the UV Image Editor in the upper-left side window . OK.

Step 3 : I create my mask (upper-ledt side window). I call it Blur_01. OK.

Step 4 : In the Upper-left side window, I open the video. It appears. No sinc yet, but so far, so good. 

Step 5 : In the Upper-left side window, I select View/Properties, in order to sync the left side and right side.


Step 6 :   In the Upper-left side window, I now tick  the Match movie length and Auto Refresh boxes… and the video disappears.


I have been trying hard over the past week to solve this problem, to little avail, so I am turning to you now. 

I also tried on Blender 2,76. I managed to move my mask around in the UV Image Editor, then I ended up with two cases :


If I start from image 1 (say image 1 to image 50), everything seems t work fine and I manage to get full sync (i.e. the mask  moves around nicely in both windows).
If I start from another image (say image 51 to 100), then I cannot get the sync and, while the mask moves around in the Upper-left side window, it stays stuck at image 51 in the Upper -right side window.


I hope I clearly stated the nature of my problem. Thanking you in advance for your time and efforts.
I recommend you to convert the video to an image secuence, you can do it with Blender if you want, render the video without changes to a series of images. Anyway I prefer using ffmpeg to do this job, is free and you have lots of examples on Internet. 

I think the problem could be that, as the video is encoded, a frame in the middle could not exist (completely) and this is why it can't show the image.