Line data    Source code

       1             : /*
       2             :  *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
       3             :  *
       4             :  *  Use of this source code is governed by a BSD-style license
       5             :  *  that can be found in the LICENSE file in the root of the source
       6             :  *  tree. An additional intellectual property rights grant can be found
       7             :  *  in the file PATENTS.  All contributing project authors may
       8             :  *  be found in the AUTHORS file in the root of the source tree.
       9             :  */
      10             : 
      11             : #include "webrtc/modules/desktop_capture/differ_block.h"
      12             : 
      13             : #include <string.h>
      14             : 
      15             : #include "webrtc/typedefs.h"
      16             : #include "webrtc/modules/desktop_capture/differ_vector_sse2.h"
      17             : #include "webrtc/system_wrappers/include/cpu_features_wrapper.h"
      18             : 
      19             : namespace webrtc {
      20             : 
      21             : namespace {
      22             : 
      23           0 : bool VectorDifference_C(const uint8_t* image1, const uint8_t* image2) {
      24           0 :   return memcmp(image1, image2, kBlockSize * kBytesPerPixel) != 0;
      25             : }
      26             : 
      27             : }  // namespace
      28             : 
      29           0 : bool VectorDifference(const uint8_t* image1, const uint8_t* image2) {
      30             :   static bool (*diff_proc)(const uint8_t*, const uint8_t*) = nullptr;
      31             : 
      32           0 :   if (!diff_proc) {
      33             : #if !defined(WEBRTC_ARCH_X86_FAMILY)
      34             :     // For ARM and MIPS processors, always use C version.
      35             :     // TODO(hclam): Implement a NEON version.
      36             :     diff_proc = &VectorDifference_C;
      37             : #else
      38           0 :     bool have_sse2 = WebRtc_GetCPUInfo(kSSE2) != 0;
      39             :     // For x86 processors, check if SSE2 is supported.
      40           0 :     if (have_sse2 && kBlockSize == 32) {
      41           0 :       diff_proc = &VectorDifference_SSE2_W32;
      42             :     } else if (have_sse2 && kBlockSize == 16) {
      43             :       diff_proc = &VectorDifference_SSE2_W16;
      44             :     } else {
      45           0 :       diff_proc = &VectorDifference_C;
      46             :     }
      47             : #endif
      48             :   }
      49             : 
      50           0 :   return diff_proc(image1, image2);
      51             : }
      52             : 
      53           0 : bool BlockDifference(const uint8_t* image1,
      54             :                      const uint8_t* image2,
      55             :                      int height,
      56             :                      int stride) {
      57           0 :   for (int i = 0; i < height; i++) {
      58           0 :     if (VectorDifference(image1, image2)) {
      59           0 :       return true;
      60             :     }
      61           0 :     image1 += stride;
      62           0 :     image2 += stride;
      63             :   }
      64           0 :   return false;
      65             : }
      66             : 
      67           0 : bool BlockDifference(const uint8_t* image1, const uint8_t* image2, int stride) {
      68           0 :   return BlockDifference(image1, image2, kBlockSize, stride);
      69             : }
      70             : 
      71             : }  // namespace webrtc