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Fixed ignoring frequencies in pHash#13
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artyom-razinov wants to merge 1 commit intoameingast:masterfrom
Closed
Fixed ignoring frequencies in pHash#13artyom-razinov wants to merge 1 commit intoameingast:masterfrom
artyom-razinov wants to merge 1 commit intoameingast:masterfrom
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15 of lowest 64 frequencies were ignored instead of suggested 1. This caused images with low details produce 0 hash (e.g.: screenshots of UI). Note that this breaks compatibility with previously generated values of pHash. I've added tests that check future possible regression of values. My references of algorithm were: http://www.hackerfactor.com/blog/index.php?/archives/432-Looks-Like-It.html#c1410
Author
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It seems that calculation is platform-dependent: tests fail on a different platform (it reproduces locally as well). |
Author
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This test fails on 32-bit iPhone 4S (iOS 9.3): testResizedRGBABitmapDataScanline
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Owner
Absolutely, but I don't want to break backwards compatibility. If you provide a new hash-type (.pHashNoFrequencies ? - I can't think of a better name) we can talk about merging this in. |
Owner
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Closing due to inactivity. |
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15 of lowest 64 frequencies were ignored instead of suggested 1. This caused images with low details produce 0 hash (e.g.: screenshots of UI).
Note that this breaks compatibility with previously generated values of pHash. I've added tests that check future possible regression of values.
My reference to the algorithm was: http://www.hackerfactor.com/blog/index.php?/archives/432-Looks-Like-It.html#c1410