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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 17:32:43 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 17:32:43 +0000
commit6bf0a5cb5034a7e684dcc3500e841785237ce2dd (patch)
treea68f146d7fa01f0134297619fbe7e33db084e0aa /media/libyuv/libyuv/source/compare_common.cc
parentInitial commit. (diff)
downloadthunderbird-6bf0a5cb5034a7e684dcc3500e841785237ce2dd.tar.xz
thunderbird-6bf0a5cb5034a7e684dcc3500e841785237ce2dd.zip
Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'media/libyuv/libyuv/source/compare_common.cc')
-rw-r--r--media/libyuv/libyuv/source/compare_common.cc74
1 files changed, 74 insertions, 0 deletions
diff --git a/media/libyuv/libyuv/source/compare_common.cc b/media/libyuv/libyuv/source/compare_common.cc
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+++ b/media/libyuv/libyuv/source/compare_common.cc
@@ -0,0 +1,74 @@
+/*
+ * Copyright 2012 The LibYuv Project Authors. All rights reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "libyuv/basic_types.h"
+
+#include "libyuv/compare_row.h"
+
+#ifdef __cplusplus
+namespace libyuv {
+extern "C" {
+#endif
+
+// Hakmem method for hamming distance.
+uint32_t HammingDistance_C(const uint8_t* src_a,
+ const uint8_t* src_b,
+ int count) {
+ uint32_t diff = 0u;
+
+ int i;
+ for (i = 0; i < count - 3; i += 4) {
+ uint32_t x = *((const uint32_t*)src_a) ^ *((const uint32_t*)src_b);
+ uint32_t u = x - ((x >> 1) & 0x55555555);
+ u = ((u >> 2) & 0x33333333) + (u & 0x33333333);
+ diff += ((((u + (u >> 4)) & 0x0f0f0f0f) * 0x01010101) >> 24);
+ src_a += 4;
+ src_b += 4;
+ }
+
+ for (; i < count; ++i) {
+ uint32_t x = *src_a ^ *src_b;
+ uint32_t u = x - ((x >> 1) & 0x55);
+ u = ((u >> 2) & 0x33) + (u & 0x33);
+ diff += (u + (u >> 4)) & 0x0f;
+ src_a += 1;
+ src_b += 1;
+ }
+
+ return diff;
+}
+
+uint32_t SumSquareError_C(const uint8_t* src_a,
+ const uint8_t* src_b,
+ int count) {
+ uint32_t sse = 0u;
+ int i;
+ for (i = 0; i < count; ++i) {
+ int diff = src_a[i] - src_b[i];
+ sse += (uint32_t)(diff * diff);
+ }
+ return sse;
+}
+
+// hash seed of 5381 recommended.
+// Internal C version of HashDjb2 with int sized count for efficiency.
+uint32_t HashDjb2_C(const uint8_t* src, int count, uint32_t seed) {
+ uint32_t hash = seed;
+ int i;
+ for (i = 0; i < count; ++i) {
+ hash += (hash << 5) + src[i];
+ }
+ return hash;
+}
+
+#ifdef __cplusplus
+} // extern "C"
+} // namespace libyuv
+#endif