Controlling fps?

jersmi's picture

Looking for ways to optimize. MAybe I'm missing something obvious -- is there a way to force a movie clip, Render in Image, etc., to skip frames to play at a specific fps? For ex., play a HD/30fps movie at 15fps? And if possible to build, would this have a significant effect on performance? Though it's apples and oranges, I'm thinking about how After Effects can skip frames when rendering for playback.

cwright's picture
Re: Controlling fps?

Some you can skip trivially, others are more difficult. RII can be gated by toggling the "Render" input each frame. This will almost certainly save you some rendering time on the off frames.

Skipping movie frames isn't likely to be a win for many codecs - anything h.264-based (or b-frame based, generally) will still need to actually decode the "skipped" frames for subsequent frame requests; you can save the draw-to-screen cost, but that's usually not too significant (it's the decode that costs). PNG, MJPEG, and "editing" codecs that don't make use of bframes can save time by skipping some frames, but you have to know the codec in advance to make this decision correctly.

jersmi's picture
Re: Controlling fps?

Thank you, Chris. I usually export or transcode to pro res, photo-jpeg, png, or other progressive codec, so that is good to know.

jersmi's picture
Re: Controlling fps?

Definitely see the difference. Here's the utility I put together. Basic but useful. Along with skipping frames, this is also set up to easily reduce the resolution of the Render in Image.

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RIIOptimization.qtz15.27 KB

idlefon's picture
Re: Controlling fps?

Cheers for this great macro jersmi! Very useful indeed ;)