#99 framebuffer producer appears to use wrong _speed

[Anonymous]

When using the framebuffer producer to slow down a clip, the frame rate that is calculated seems to be based on the frame rate of the consumer profile (or maybe a default frame rate?), not the frame rate of the actual source.

For example, if i have a 50fps video, and slow it down with the following melt command line:

melt -profile hdv_720_25p framebuffer:50fps_video_file.mov?0.5

The resulting playback of the video appears to be at 12.5fps, not 25fps. However, if i change the output profile to be 50p (with the following command line):

melt -profile hdv_720_50p framebuffer:50fps_video_file.mov?0.5

The resulting playback of the video appears to be correct at 25fps (half of the source videos 50fps).

At a rough guess (I've only had a quick look through the code), it seems that it uses the profiles frame rate to calculate the frame position of the source video, truncating it, rather than using the source videos actual frame rate to get the frame from the producer. Or maybe its using a default frame rate rather than the source videos.

This bug should be reproducible with any 50 or 60fps video, but if you need a example clip, let me know (I didnt attach one as my broadband is not very broad at about 128kbps upload speed).

[Dan Dennedy]

This is the behaviour by design.

[Dan Dennedy]

With that said, I understand the motivation, and we need a way to accommodate it. So, I'll re-open this. hmm... maybe this should be design. However, a change in default behavior would affect existing projects.