[Ffmpeg-devel] [RFC, Request for testing, PATCH] snow wavelet fliping

Stefan de Konink skinkie
Tue Jan 2 19:47:38 CET 2007

On Tue, 2 Jan 2007, Michael Niedermayer wrote:

> -> some signals simply can be represented much more compactly in the
>    wavelet domain if they are shifted a little
> if we now always encode images with the same shift then there is a much
> higher chance that some signals will be always hard to store, if OTOH
> we flip the wavelet after each frame then what cannot easily be stored
> (= gets quantized to 0) in the even frames can with some luck more easily
> be stored in the odd frames

So if I get this right; if this is tied to a local motion predictor which
results a local direction. It could find the optimal local shift?

Or wouldn't this be possible because the wavelet will be rotated and
cannot be applied to the image in decoding. I'm surprised a fixed 180
degree turn 'just' works better.

Yours Sincerely,

Stefan de Konink

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