.MTS video clips randomly rendering with faster frame rates

Hello everyone!

First I am a new guy who just got blender a week or so ago and have watch many video series in an effort at learning some it’s functionality. Specifically I want to use it mostly as a video editor and find it works very well. In fact, so far I absolutely love the program which is why I am trying SO hard to make it work for my use.

I take video with an HD camera that records clips in .MTS format. I have it set to record at 29 FPS with a 1920 resolution. The properties for the clips shows it as a 29 FPS clip. Blender however reads it as a 59 FPS clip.

When I load the clips at their correct FR it has the video half the length of the audio. To make it match I have to change the FR to 59 in blender. It then matches perfectly. I also found I have to deinterlace each clip or it’s a giant mess. So far so good. It seems to edit fine and I then try to render the finished product. Unfortunately the yield ends up with a random clip or two that runs at super speed as if the FR change to 59 did no apply to that particular clip for some reason.

The final two clips in this image both rendered super fast The original clips are all exactly the same. Does anyone have an idea what might be causing this?

The image insertion is not working. If necessary I can upload it later.

I will continue to try different things and change one thing then render until something fixes the problem or reveals what is causing it. If anyone has any ideas on why might cause this I would be willing to test it. My main concern is:

  1. Why does Blender see the clips as 59 FPS when the properties of the clip on my computer show it as 29?
  2. Why is the video in the clip displayed by blender at a different length than the audio unless I change the FR to 59? I suppose this is because blender sees the clip as a 59 FR clip but then why is not displaying the audio at that rate?
  3. Why are some clips rendering fine while others render at super speed? As if the clip does not recognize that I changed the FR to 59.

Today I will put one of the clip that is not rendering properly in by itself and see if it renders O.K. If it renders ok then it’s not the clip but how Blender sees it after I edited another clip or put another clip in front of it. Perhaps when I do something like this it messes up blender’s recognition of the clip in question.

Well, I put the clip that was not rendering properly in the sequencer alone and did not edit the clip at all and it still rendered at super speed as if it did not recognize my change of frame rate in the settings. So it looks like some clips are randomly read differently by Blender. Keep in mind that no change was made to the camera from one clip to the next and no change was made to the clips after they were transferred to the computer. The properties of the clips have nothing different other than minor data rate changes. I am stumped.

I am guessing the only work around for me here is to find a good converter to change the .MTS into something that Blender is not having trouble with. I will search for one now. Does anyone have a suggestion for the best format for the clips and converter?

I am narrowing the problem down. If I do NOT deinterlace the clip it renders at the correct speed. The problem is it looks horrid with all the weird wrinkles in it. So deinterlacing makes it look better but somehow screws up random clips.

OK, I have found the problem and a work around. When highlighting the clips using the “b” hotkey the interlace option does not activate on all the clips only the first one. Nor does it deinterlace the audio portion of the clip. If I manually select the audio portion first and then the video portion it allows me to deinterlace and apparently does both because that solved the problem.

I will keep you guys informed if I find any other issues with it.

Well, I rendered a 20+ clip piece and three or four of the clip ran fast. I guess I am running out of energy diagnosing the problem/solution through I still believe it has something to do with the dinterlacing. I got the Freemake video converter which is pretty good if you can avoid getting their crapware installed during installation. Converting now to h264 and will then try to render the clips again.

I am hopeful this works as I really like Blender and am willing to even go the extra step of converting before editing. But it would be nice if this got fixed because it seems so very close to working right now. Anyhow I will keep you guys updated on the h264.

After converting the files in Freemake the preview was horrid at about 2 or three FPS so I did a proxy/timecode which bumped it to 30 fps. Going to finish editing and let you know how it goes but I am optimistic.

So my steps in movie creation will be as follows:

  1. Convert .mts to .avi in Freemake
  2. Put in Blender
  3. Create proxy in blender.
  4. Make liberal use of Sequence Update button (or it does not use the proxy after an edit)
  5. Render in h264

It worked :slight_smile: