AverageHash

AverageHash

Algorithm: Reduce size. Remove high frequencies and detail by shrinking to 8x8 so that there are 64 total pixels. Reduce color. The tiny 8x8 picture is converted to a grayscale. Average the colors. Compute the mean value of the 64 colors. Compute the bits. Each bit is simply set based on whether the color value is above or below the mean. Construct the hash. Set the 64 bits into a 64-bit integer. The order does not matter, just as long as you are consistent.

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