Merge pull request #1 from octu0/fix-32x2-64x1

minor tune wavelethash

README.md

@@ -31,26 +31,26 @@ pkg: github.com/octu0/fastimagehash
 cpu: Intel(R) Core(TM) i5-8210Y CPU @ 1.60GHz
 BenchmarkAverageHash
 BenchmarkAverageHash/goimagehash/8x8
-BenchmarkAverageHash/goimagehash/8x8-4         	    2772	    432437 ns/op
+BenchmarkAverageHash/goimagehash/8x8-4         	    2707	    424327 ns/op
 BenchmarkAverageHash/goimagehash/32x32
-BenchmarkAverageHash/goimagehash/32x32-4       	    1951	    567546 ns/op
+BenchmarkAverageHash/goimagehash/32x32-4       	    1836	    570279 ns/op
 BenchmarkAverageHash/fastimagehash/32x32
-BenchmarkAverageHash/fastimagehash/32x32-4     	   39063	     32761 ns/op
+BenchmarkAverageHash/fastimagehash/32x32-4     	   39634	     29911 ns/op
 BenchmarkDifferenceHash
 BenchmarkDifferenceHash/goimagehash/9x8
-BenchmarkDifferenceHash/goimagehash/9x8-4      	    2305	    522748 ns/op
+BenchmarkDifferenceHash/goimagehash/9x8-4      	    2277	    456987 ns/op
 BenchmarkDifferenceHash/goimagehash/33x32
-BenchmarkDifferenceHash/goimagehash/33x32-4    	    1864	    790872 ns/op
+BenchmarkDifferenceHash/goimagehash/33x32-4    	    1874	    592438 ns/op
 BenchmarkDifferenceHash/fastimagehash/33x32
-BenchmarkDifferenceHash/fastimagehash/33x32-4  	   27858	     43084 ns/op
+BenchmarkDifferenceHash/fastimagehash/33x32-4  	   33601	     34354 ns/op
 BenchmarkPerceptionHash
 BenchmarkPerceptionHash/goimagehash/64x64
-BenchmarkPerceptionHash/goimagehash/64x64-4    	    1240	    883755 ns/op
+BenchmarkPerceptionHash/goimagehash/64x64-4    	    1311	    813998 ns/op
 BenchmarkPerceptionHash/fastimagehash/64x64
-BenchmarkPerceptionHash/fastimagehash/64x64-4  	    6826	    164496 ns/op
+BenchmarkPerceptionHash/fastimagehash/64x64-4  	    7542	    146732 ns/op
 BenchmarkWaveletHash
 BenchmarkWaveletHash/fastimagehash/64x64
-BenchmarkWaveletHash/fastimagehash/64x64-4     	    5572	    206503 ns/op
+BenchmarkWaveletHash/fastimagehash/64x64-4     	    6045	    191712 ns/op
 ```
 
 # License

version.go

@@ -2,5 +2,5 @@ package fastimagehash
 
 const (
 	AppName string = "fastimagehash"
-	Version string = "0.0.2"
+	Version string = "0.0.3"
 )

wavelethash.go

@@ -31,44 +31,36 @@ func WaveletHash(in image.Image) (Hash1024, error) {
 		return Hash1024{}, errors.WithStack(err)
 	}
 	median := pickMedian(hi)
-	return wavelethash32x32(hi, median), nil
+	return wavelethash64x16(hi, median), nil
 }
 
-func wavelethash32x32(hi []float32, median float32) Hash1024 {
+func wavelethash64x16(hi []float32, median float32) Hash1024 {
 	return [16]uint64{
-		wavelethash32x2(hi[0:32], hi[32:64], median),
-		wavelethash32x2(hi[64:96], hi[96:128], median),
-		wavelethash32x2(hi[128:160], hi[160:192], median),
-		wavelethash32x2(hi[192:224], hi[224:256], median),
-		wavelethash32x2(hi[256:288], hi[288:320], median),
-		wavelethash32x2(hi[320:352], hi[352:384], median),
-		wavelethash32x2(hi[384:416], hi[416:448], median),
-		wavelethash32x2(hi[448:480], hi[480:512], median),
-		wavelethash32x2(hi[512:544], hi[544:576], median),
-		wavelethash32x2(hi[576:608], hi[608:640], median),
-		wavelethash32x2(hi[640:672], hi[672:704], median),
-		wavelethash32x2(hi[704:736], hi[736:768], median),
-		wavelethash32x2(hi[768:800], hi[800:832], median),
-		wavelethash32x2(hi[832:864], hi[864:896], median),
-		wavelethash32x2(hi[896:928], hi[928:960], median),
-		wavelethash32x2(hi[960:992], hi[992:1024], median),
+		wavelethash64x1(hi[0:64], median),
+		wavelethash64x1(hi[64:128], median),
+		wavelethash64x1(hi[128:192], median),
+		wavelethash64x1(hi[192:256], median),
+		wavelethash64x1(hi[256:320], median),
+		wavelethash64x1(hi[320:384], median),
+		wavelethash64x1(hi[384:448], median),
+		wavelethash64x1(hi[448:512], median),
+		wavelethash64x1(hi[512:576], median),
+		wavelethash64x1(hi[576:640], median),
+		wavelethash64x1(hi[640:704], median),
+		wavelethash64x1(hi[704:768], median),
+		wavelethash64x1(hi[768:832], median),
+		wavelethash64x1(hi[832:896], median),
+		wavelethash64x1(hi[896:960], median),
+		wavelethash64x1(hi[960:1024], median),
 	}
 }
 
-func wavelethash32x2(a, b []float32, median float32) uint64 {
+func wavelethash64x1(signal []float32, median float32) uint64 {
 	index := uint64(0)
-	pos := 0
-	for i := 0; i < 32; i += 1 {
-		if median < a[i] {
-			index |= 1 << (64 - pos - 1)
+	for i := 0; i < 64; i += 1 {
+		if median < signal[i] {
+			index |= 1 << (64 - i - 1)
 		}
-		pos += 1
-	}
-	for i := 0; i < 32; i += 1 {
-		if median < b[i] {
-			index |= 1 << (64 - pos - 1)
-		}
-		pos += 1
 	}
 	return index
 }