AV1 beats x264 and libvpx-vp9 in practical use case

Re:AV1 beats x264 and libvpx-vp9 in practical use case by jd20 on Wednesday April 11, 2018 @04:27AM (#16809101)

The delta encoding will be more efficient with higher frame rate, but also x264 has a tweak which decreases quality factor as frame rate increases. Why? The reasoning was that, since the frame is displayed for less time, you don't have as much time to appreciate the details and hence fewer bits can be used, while still maintaining the same perceptual quality.

I found this out the hard way when encoding time lapses, even if the delta between frames is identical, the final choice of frame rate greatly affects output file size.

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Re:AV1 beats x264 and libvpx-vp9 in practical use case by hnaccy on Wednesday April 11, 2018 @05:39AM (#16809448)

If all frames have lower quality wouldn't it still be perceived regardless of frame rate?

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Re:AV1 beats x264 and libvpx-vp9 in practical use case by mAritz on Wednesday April 11, 2018 @07:12AM (#16809899)

I'm no expert but I would say no. Each frame delta might have less/same information, but since you're applying more deltas/second, it gets better again.

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Re:AV1 beats x264 and libvpx-vp9 in practical use case by vanderZwan on Wednesday April 11, 2018 @07:07PM (#16816606)

Wouldn't this lead to bigger error accumulation? At least, my gut feeling says "less information per delta = larger error accumulation", and on top of that we have more deltas/second

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Re:AV1 beats x264 and libvpx-vp9 in practical use case by vanderZwan on Wednesday April 11, 2018 @05:35AM (#16809429)

Oooooof, now that is a good thing to know.

Speaking from experience with recording 120fps, which inevitably stutters on playback unless shown at half speed, I suppose also that it is a matter of "if the CPU can't keep up decoding, there is no point"

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