Changeset 5633 for pjproject/trunk/third_party/yuv/source/compare_common.cc

Timestamp:

Jul 28, 2017 2:51:44 AM (7 years ago)

Author:

nanang

Message:

Re #2004: Update libyuv version from libyuv git master repo dated 27 July 2017, the compile errors on old gcc versions issue persists though.

File:

• pjproject/trunk/third_party/yuv/source/compare_common.cc (modified) (1 diff)

pjproject/trunk/third_party/yuv/source/compare_common.cc

@@ -17 +17 @@
 extern "C" {
 #endif
+
+#if ORIGINAL_OPT
+uint32 HammingDistance_C(const uint8* src_a, const uint8* src_b, int count) {
+  uint32 diff = 0u;
+
+  int i;
+  for (i = 0; i < count; ++i) {
+    int x = src_a[i] ^ src_b[i];
+    if (x & 1)
+      ++diff;
+    if (x & 2)
+      ++diff;
+    if (x & 4)
+      ++diff;
+    if (x & 8)
+      ++diff;
+    if (x & 16)
+      ++diff;
+    if (x & 32)
+      ++diff;
+    if (x & 64)
+      ++diff;
+    if (x & 128)
+      ++diff;
+  }
+  return diff;
+}
+#endif
+
+// Hakmem method for hamming distance.
+uint32 HammingDistance_C(const uint8* src_a, const uint8* src_b, int count) {
+  uint32 diff = 0u;
+
+  int i;
+  for (i = 0; i < count - 3; i += 4) {
+    uint32 x = *((uint32*)src_a) ^ *((uint32*)src_b);
+    uint32 u = x - ((x >> 1) & 0x55555555);
+    u = ((u >> 2) & 0x33333333) + (u & 0x33333333);
+    diff += ((((u + (u >> 4)) & 0x0f0f0f0f) * 0x01010101) >> 24);
+    src_a += 4;
+    src_b += 4;
+  }
+  return diff;
+}
 
 uint32 SumSquareError_C(const uint8* src_a, const uint8* src_b, int count) {