5 ms·
The image that they show reminds me of the way that the 2D discrete cosine transform works. http://openi.nlm.nih.gov/imgs/512/312/2680596/2680596_pone.0005594.
by oakwhiz 13y ago
The image that they show reminds me of the way that the 2D discrete cosine transform works.
http://openi.nlm.nih.gov/imgs/512/312/2680596/2680596_pone.0005594.g002.png http://openi.nlm.nih.gov/imgs/512/312/2680596/2680596_pone.0...
It looks similar to this:
https://upload.wikimedia.org/wikipedia/commons/2/23/Dctjpeg.png https://upload.wikimedia.org/wikipedia/commons/2/23/Dctjpeg....
- mistercow 13y agoIt's called a "Gabor patch", and it's constructed by multiplying a 1D sine wave by a 2D gaussian window (it's the sine wave that's reminding you of the basis functions of the 2D DCT). You'll see these all over the place if you read studies about vision. The (highly oversimplified) reason is that if you imagine the edge-detection processes of a mammalian brain as a set of filters, the impulse response of one of those filters would be a Gabor patch. This is related to why the DCT is so effective for vision applications, although perhaps less significantly than you might imagine just by looking at the patterns.
- TTPrograms 13y agoEven more closely related would be a wavelet transform with windowed sine packet wavelets.
- eru 13y agoReminds me of the game Frequon Invaders. (https://duckduckgo.com/?q=!i+frequon+invaders https://duckduckgo.com/?q=!i+frequon+invaders)