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I'm confused about why this would be a good way to save bandwidth. The same number of pixels are still required to give you a smooth picture. So unless Skype ad
by eurleif 13y ago
I'm confused about why this would be a good way to save bandwidth. The same number of pixels are still required to give you a smooth picture. So unless Skype adds more pixels to the zoomed-in area (which would presumably negate the bandwidth savings), you're still getting reduced resolution. Why not forget the zooming and just reduce resolution?
- JoeAltmaier 13y agoThe camera delivers a fixed resolution. Zooming by necessity reduces resolution of the displayed image, you could probably notice if you were looking for it. Net number of bits crossing the wire is reduced so its a win.
- Dylan16807 13y ago>The camera delivers a fixed resolution. I think you misunderstood the question. Cropping and scaling are both software choices for reducing resolution, so the question is why crop specifically?
- baddox 13y agoI assume the heuristic they're using is that single faces are the primary use case, and will tend to be in the center of the frame. If I'm right, their solution would use more of the available bandwidth resolving the user's face rather than anything which may be in the background.
- jloughry 13y agoThat's how the human eye works; there are denser "pixels" in the foveal (central) region of the retina.
- georgemcbay 13y agoOTOH, things in the background are unlikely to move much which is ideal for frame-to-frame compression, so getting rid of those areas is unlikely to really buy you much.
- jloughry 13y agoI am certain the camera on the remote end was incapable of optically zooming. Skype evidently took the HD frame from the camera on that end, cropped it to something like VGA size, and sent only those pixels across the wire. On my end, it was re-sampled and displayed full-size. The picture on my end did not change physical size; it looked as if the camera zoomed in. Mainly, I was impressed by how smoothly and seamlessly it was done.
- huxley 13y agoAdding a Gaussian blur to images can significantly increase their compressability (for many codecs), perhaps that is what's happening here?