http://yshblog.com/blog/44
DCT images and his, is poor hamming distance is too far away,,
Who has the DELPHI version PHASH provide? Thank you, all give you,
CodePudding user response:
Phash algorithm,1. The input image, if it is an RGB image is converted into gray image
2. The scaling, the image zooming is 32 x32 image size, note that at this point is not 8 by 8
3. DCT transform, the above 32 x32 image DCT transform
4. Low frequency, the image size is 32 x32 after transformation, if as the fingerprint image will waste too much space, so I only take low frequency part, after the transformation of the upper left 8 by 8 pieces of
5. Average, calculated the 8 by 8 pieces of all pixels of average
6. Quantitative comparison of 8 by 8 pieces of each pixel in the relationship between average size, if is greater than the average, the fingerprints on the corresponding value is 1; Otherwise, is 0,
Combination, the 64 - bit 0 and 1 of the image of the fingerprint (for hamming distance calculation),
CodePudding user response:
Did not know some player?