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The Case for VP9

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Bad math (Score: 1)

by fnj@pipedot.org on 2015-06-13 21:41 (#B6Q9)

The VP9 codec can reduce the bandwidth needed to play a video by up to 35 percent, according to Google. This means that a user who was previously relegated to watching 480p video should now be able to watch 720p, for example.
No, it means no such thing. 480p -> 640x480 -> 307,200 px; 720p -> 1280x720 -> 921,600 px. Both are the same framerate. So 480p is not 65% of the bandwidth of 720p, it is 33.3%.

Re: Bad math (Score: 2, Informative)

by evilviper@pipedot.org on 2015-06-14 01:09 (#B718)

480p is not 65% of the bandwidth of 720p, it is 33.3%.
You're mistaken... You're using uncompressed numbers, while video compression does NOT scale-up linearly like that, at all. It does NOT take 4X the bandwidth just because the picture has 4X as many pixels. I generally ballpark a doubling of frame-rate or resolution as a 50% increase in bandwidth, and it's quite possible to do better.

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2015-06-14 01:09
480p is not 65% of the bandwidth of 720p, it is 33.3%.
You're mistaken... You're using uncompressed numbers, while video compression does NOT scale-up linearly like that, at all. It does NOT take 4X the bandwidth just because the picture has 4X as many pixels. I generally ballpark a doubling of frame-rate or resolution as a 33% increase in bandwidth, and it's quite possible to do better.
2015-06-14 01:09
480p is not 65% of the bandwidth of 720p, it is 33.3%.
You're mistaken... You're using uncompressed numbers, while video compression does NOT scale-up linearly like that, at all. It does NOT take 4X the bandwidth just because the picture has 4X as many pixels. I generally ballpark a doubling of frame-rate or resolution as a 3350% increase in bandwidth, and it's quite possible to do better.

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2015-06-22 17:50 Informative +1 renevith@pipedot.org

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