Bug with 1080p 60 fps .mp4 output

[Natal]

It is possible that this bug may already be known, but if not.....

I recently upgraded my camcorder to a Canon Vixia HF G30. One of the features of this model is that it can produce AVCHD clips up to 28 mbps and MP4 clips up to 35 mbps (both at 60 fps progressive). H.264 is the codec used in both cases.

So, I have been doing a fair bit of test footage the last few days, and the quality is noticeably better than the output from my old HF S10.

Nowdays I do most of my editing with Premier Pro, but I loaded a few clips into VS6 to see if it could deal with the new footage.

Unfortunately the answer was no. I set output using the "same as first clip" option to preserve the properties of the footage. The problem was even though the output was roughly the expected size and showed up as having the correct properties, it was a lot jerkier than the original.

Inspecting the output frame by frame in PP showed that although the output was 60 fps and about the right bit rate, VS6 was actually outputting 30 fps, but duplicating every 2nd frame to make up 60 fps. This is what was causing the jerking effect.

So, if you are shooting at 60 fps progressive with a modern camera, VS6 is not going to satisfy. IMO the encoder portion of the program needs a major revision.

[Ken Berry]

That's odd. I do a fair bit of editing of my GoPro mp4 1080p -- though at PAL's 50 fps -- and the results are smooth. However, I don't use "Same as first clip". Instead I have made my own Custom template using Make Movie Template Manager > Add, then navigating to one of my 50p original clips. I give the template a name, and thereafter use Share > Create Video File > Custom and select my 50p template.

I assume you had ticked 'Enable 50/60p editing' under Settings?

[Natal]

Ticking the enable 50/60 fps editing didn't appear to make any difference. I think that is just for editing properties, not the actual rendering.

[Kingston]

Did you remember to set the project to 60? If you don't, it will treat the video on the timeline like it's 30.