Nagram/TMessagesProj/jni/libyuv/source/compare_common.cc

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/*
* 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"
#ifdef __cplusplus
namespace libyuv {
extern "C" {
#endif
uint32 SumSquareError_C(const uint8* src_a, const uint8* src_b, int count) {
uint32 sse = 0u;
int i;
for (i = 0; i < count; ++i) {
int diff = src_a[i] - src_b[i];
sse += (uint32)(diff * diff);
}
return sse;
}
// hash seed of 5381 recommended.
// Internal C version of HashDjb2 with int sized count for efficiency.
uint32 HashDjb2_C(const uint8* src, int count, uint32 seed) {
uint32 hash = seed;
int i;
for (i = 0; i < count; ++i) {
hash += (hash << 5) + src[i];
}
return hash;
}
#ifdef __cplusplus
} // extern "C"
} // namespace libyuv
#endif