talk/session/phone/testutils.cc - vendor/opensource/libjingle - Git at Google

 /*
  * libjingle
  * Copyright 2004 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *  1. Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright notice,
  *     this list of conditions and the following disclaimer in the documentation
  *     and/or other materials provided with the distribution.
  *  3. The name of the author may not be used to endorse or promote products
  *     derived from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
  * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 #include "talk/session/phone/testutils.h"

 #include <math.h>

 #ifdef HAVE_YUV
 #include "libyuv/compare.h"
 #endif
 #include "talk/base/bytebuffer.h"
 #include "talk/base/fileutils.h"
 #include "talk/base/gunit.h"
 #include "talk/base/pathutils.h"
 #include "talk/base/stream.h"
 #include "talk/base/stringutils.h"
 #include "talk/session/phone/rtpdump.h"
 #include "talk/session/phone/videocapturer.h"
 #include "talk/session/phone/videoframe.h"

 namespace cricket {

 /////////////////////////////////////////////////////////////////////////
 // Implementation of RawRtpPacket
 /////////////////////////////////////////////////////////////////////////
 void RawRtpPacket::WriteToByteBuffer(
     uint32 in_ssrc, talk_base::ByteBuffer *buf) const {
   if (!buf) return;

   buf->WriteUInt8(ver_to_cc);
   buf->WriteUInt8(m_to_pt);
   buf->WriteUInt16(sequence_number);
   buf->WriteUInt32(timestamp);
   buf->WriteUInt32(in_ssrc);
   buf->WriteBytes(payload, sizeof(payload));
 }

 bool RawRtpPacket::ReadFromByteBuffer(talk_base::ByteBuffer* buf) {
   if (!buf) return false;

   bool ret = true;
   ret &= buf->ReadUInt8(&ver_to_cc);
   ret &= buf->ReadUInt8(&m_to_pt);
   ret &= buf->ReadUInt16(&sequence_number);
   ret &= buf->ReadUInt32(&timestamp);
   ret &= buf->ReadUInt32(&ssrc);
   ret &= buf->ReadBytes(payload, sizeof(payload));
   return ret;
 }

 bool RawRtpPacket::SameExceptSeqNumTimestampSsrc(
     const RawRtpPacket& packet, uint16 seq, uint32 ts, uint32 ssc) const {
   return sequence_number == seq &&
       timestamp == ts &&
       ver_to_cc == packet.ver_to_cc &&
       m_to_pt == packet.m_to_pt &&
       ssrc == ssc &&
       0 == memcmp(payload, packet.payload, sizeof(payload));
 }

 /////////////////////////////////////////////////////////////////////////
 // Implementation of RawRtcpPacket
 /////////////////////////////////////////////////////////////////////////
 void RawRtcpPacket::WriteToByteBuffer(talk_base::ByteBuffer *buf) const {
   if (!buf) return;

   buf->WriteUInt8(ver_to_count);
   buf->WriteUInt8(type);
   buf->WriteUInt16(length);
   buf->WriteBytes(payload, sizeof(payload));
 }

 bool RawRtcpPacket::ReadFromByteBuffer(talk_base::ByteBuffer* buf) {
   if (!buf) return false;

   bool ret = true;
   ret &= buf->ReadUInt8(&ver_to_count);
   ret &= buf->ReadUInt8(&type);
   ret &= buf->ReadUInt16(&length);
   ret &= buf->ReadBytes(payload, sizeof(payload));
   return ret;
 }

 bool RawRtcpPacket::EqualsTo(const RawRtcpPacket& packet) const {
   return ver_to_count == packet.ver_to_count &&
       type == packet.type &&
       length == packet.length &&
       0 == memcmp(payload, packet.payload, sizeof(payload));
 }

 /////////////////////////////////////////////////////////////////////////
 // Implementation of class RtpTestUtility
 /////////////////////////////////////////////////////////////////////////
 const RawRtpPacket RtpTestUtility::kTestRawRtpPackets[] = {
     {0x80, 0, 0, 0,  RtpTestUtility::kDefaultSsrc, "RTP frame 0"},
     {0x80, 0, 1, 30, RtpTestUtility::kDefaultSsrc, "RTP frame 1"},
     {0x80, 0, 2, 30, RtpTestUtility::kDefaultSsrc, "RTP frame 1"},
     {0x80, 0, 3, 60, RtpTestUtility::kDefaultSsrc, "RTP frame 2"}
 };
 const RawRtcpPacket RtpTestUtility::kTestRawRtcpPackets[] = {
     // The Version is 2, the Length is 2, and the payload has 8 bytes.
     {0x80, 0, 2, "RTCP0000"},
     {0x80, 0, 2, "RTCP0001"},
     {0x80, 0, 2, "RTCP0002"},
     {0x80, 0, 2, "RTCP0003"},
 };

 size_t RtpTestUtility::GetTestPacketCount() {
   return talk_base::_min(
       ARRAY_SIZE(kTestRawRtpPackets),
       ARRAY_SIZE(kTestRawRtcpPackets));
 }

 bool RtpTestUtility::WriteTestPackets(
     size_t count, bool rtcp, uint32 rtp_ssrc, RtpDumpWriter* writer) {
   if (!writer || count > GetTestPacketCount()) return false;

   bool result = true;
   uint32 elapsed_time_ms = 0;
   for (size_t i = 0; i < count && result; ++i) {
     talk_base::ByteBuffer buf;
     if (rtcp) {
       kTestRawRtcpPackets[i].WriteToByteBuffer(&buf);
     } else {
       kTestRawRtpPackets[i].WriteToByteBuffer(rtp_ssrc, &buf);
     }

     RtpDumpPacket dump_packet(buf.Data(), buf.Length(), elapsed_time_ms, rtcp);
     elapsed_time_ms += kElapsedTimeInterval;
     result &= (talk_base::SR_SUCCESS == writer->WritePacket(dump_packet));
   }
   return result;
 }

 bool RtpTestUtility::VerifyTestPacketsFromStream(
     size_t count, talk_base::StreamInterface* stream, uint32 ssrc) {
   if (!stream) return false;

   uint32 prev_elapsed_time = 0;
   bool result = true;
   stream->Rewind();
   RtpDumpLoopReader reader(stream);
   for (size_t i = 0; i < count && result; ++i) {
     // Which loop and which index in the loop are we reading now.
     size_t loop = i / GetTestPacketCount();
     size_t index = i % GetTestPacketCount();

     RtpDumpPacket packet;
     result &= (talk_base::SR_SUCCESS == reader.ReadPacket(&packet));
     // Check the elapsed time of the dump packet.
     result &= (packet.elapsed_time >= prev_elapsed_time);
     prev_elapsed_time = packet.elapsed_time;

     // Check the RTP or RTCP packet.
     talk_base::ByteBuffer buf(reinterpret_cast<const char*>(&packet.data[0]),
                               packet.data.size());
     if (packet.is_rtcp) {
       // RTCP packet.
       RawRtcpPacket rtcp_packet;
       result &= rtcp_packet.ReadFromByteBuffer(&buf);
       result &= rtcp_packet.EqualsTo(kTestRawRtcpPackets[index]);
     } else {
       // RTP packet.
       RawRtpPacket rtp_packet;
       result &= rtp_packet.ReadFromByteBuffer(&buf);
       result &= rtp_packet.SameExceptSeqNumTimestampSsrc(
           kTestRawRtpPackets[index],
           kTestRawRtpPackets[index].sequence_number +
               loop * GetTestPacketCount(),
           kTestRawRtpPackets[index].timestamp + loop * kRtpTimestampIncrease,
           ssrc);
     }
   }

   stream->Rewind();
   return result;
 }

 bool RtpTestUtility::VerifyPacket(const RtpDumpPacket* dump,
                                   const RawRtpPacket* raw,
                                   bool header_only) {
   if (!dump || !raw) return false;

   talk_base::ByteBuffer buf;
   raw->WriteToByteBuffer(RtpTestUtility::kDefaultSsrc, &buf);

   if (header_only) {
     size_t header_len = 0;
     dump->GetRtpHeaderLen(&header_len);
     return header_len == dump->data.size() &&
         buf.Length() > dump->data.size() &&
         0 == memcmp(buf.Data(), &dump->data[0], dump->data.size());
   } else {
     return buf.Length() == dump->data.size() &&
         0 == memcmp(buf.Data(), &dump->data[0], dump->data.size());
   }
 }

 // Implementation of VideoCaptureListener.
 VideoCapturerListener::VideoCapturerListener(VideoCapturer* capturer)
     : start_result_(CR_PENDING),
       frame_count_(0),
       frame_fourcc_(0),
       frame_width_(0),
       frame_height_(0),
       frame_size_(0),
       resolution_changed_(false) {
   capturer->SignalStartResult.connect(this,
       &VideoCapturerListener::OnStartResult);
   capturer->SignalFrameCaptured.connect(this,
       &VideoCapturerListener::OnFrameCaptured);
   capturer->SignalCaptureEvent.connect(this,
       &VideoCapturerListener::OnCaptureEvent);
 }

 void VideoCapturerListener::OnStartResult(VideoCapturer* capturer,
                                           CaptureResult result) {
   start_result_ = result;
 }

 void VideoCapturerListener::OnFrameCaptured(VideoCapturer* capturer,
                                             const CapturedFrame* frame) {
   ++frame_count_;
   if (1 == frame_count_) {
     frame_fourcc_ = frame->fourcc;
     frame_width_ = frame->width;
     frame_height_ = frame->height;
     frame_size_ = frame->data_size;
   } else if (frame_width_ != frame->width || frame_height_ != frame->height) {
     resolution_changed_ = true;
   }
 }

 void VideoCapturerListener::OnCaptureEvent(VideoCapturer* capturer,
                                            CaptureEvent ev) {
 }


 // Returns the absolute path to a file in the testdata/ directory.
 std::string GetTestFilePath(const std::string& filename) {
   // Locate test data directory.
   talk_base::Pathname path = GetTalkDirectory();
   EXPECT_FALSE(path.empty());  // must be run from inside "talk"
   path.AppendFolder("session");
   path.AppendFolder("phone");
   path.AppendFolder("testdata");
   path.SetFilename(filename);
   return path.pathname();
 }

 // PSNR formula: psnr = 10 * log10 (Peak Signal^2 / mse)
 // sse is set to a small number for identical frames or sse == 0
 double ComputePSNR(double sse, double size) {
   if (sse <= 0.)
     sse = 65025.0 * size / pow(10., 128./10.);  // produces max PSNR of 128
   return 10.0 * log10(65025.0 * size / sse);
 }

 double ComputeSumSquareError(const uint8 *org, const uint8 *rec, int size) {
 #ifdef HAVE_YUV
   return static_cast<double>(libyuv::ComputeSumSquareError(org, rec, size));
 #else
   double sse = 0.;
   for (int j = 0; j < size; ++j) {
     const int diff = static_cast<int>(org[j]) - static_cast<int>(rec[j]);
     sse += static_cast<double>(diff * diff);
   }
   return sse;
 #endif
 }

 // Loads the image with the specified prefix and size into |out|.
 bool LoadPlanarYuvTestImage(const std::string& prefix,
                             int width, int height, uint8* out) {
   std::stringstream ss;
   ss << prefix << "." << width << "x" << height << "_P420.yuv";

   talk_base::scoped_ptr<talk_base::FileStream> stream(
       talk_base::Filesystem::OpenFile(talk_base::Pathname(
           GetTestFilePath(ss.str())), "rb"));
   if (!stream.get()) {
     return false;
   }

   talk_base::StreamResult res =
       stream->ReadAll(out, I420_SIZE(width, height), NULL, NULL);
   return (res == talk_base::SR_SUCCESS);
 }

 // Dumps the YUV image out to a file, for visual inspection.
 // PYUV tool can be used to view dump files.
 void DumpPlanarYuvTestImage(const std::string& prefix, const uint8* img,
                             int w, int h) {
   talk_base::FileStream fs;
   char filename[256];
   talk_base::sprintfn(filename, sizeof(filename), "%s.%dx%d_P420.yuv",
                       prefix.c_str(), w, h);
   fs.Open(filename, "wb", NULL);
   fs.Write(img, I420_SIZE(w, h), NULL, NULL);
 }

 // Dumps the ARGB image out to a file, for visual inspection.
 // ffplay tool can be used to view dump files.
 void DumpPlanarArgbTestImage(const std::string& prefix, const uint8* img,
                              int w, int h) {
   talk_base::FileStream fs;
   char filename[256];
   talk_base::sprintfn(filename, sizeof(filename), "%s.%dx%d_ARGB.raw",
                       prefix.c_str(), w, h);
   fs.Open(filename, "wb", NULL);
   fs.Write(img, ARGB_SIZE(w, h), NULL, NULL);
 }

 bool VideoFrameEqual(const VideoFrame* frame0, const VideoFrame* frame1) {
   const uint8* y0 = frame0->GetYPlane();
   const uint8* u0 = frame0->GetUPlane();
   const uint8* v0 = frame0->GetVPlane();
   const uint8* y1 = frame1->GetYPlane();
   const uint8* u1 = frame1->GetUPlane();
   const uint8* v1 = frame1->GetVPlane();

   for (size_t i = 0; i < frame0->GetHeight(); ++i) {
     if (0 != memcmp(y0, y1, frame0->GetWidth())) {
       return false;
     }
     y0 += frame0->GetYPitch();
     y1 += frame1->GetYPitch();
   }

   for (size_t i = 0; i < frame0->GetChromaHeight(); ++i) {
     if (0 != memcmp(u0, u1, frame0->GetChromaWidth())) {
       return false;
     }
     if (0 != memcmp(v0, v1, frame0->GetChromaWidth())) {
       return false;
     }
     u0 += frame0->GetUPitch();
     v0 += frame0->GetVPitch();
     u1 += frame1->GetUPitch();
     v1 += frame1->GetVPitch();
   }

   return true;
 }

 }  // namespace cricket
	/*
	* libjingle
	* Copyright 2004 Google Inc.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are met:
	*
	* 1. Redistributions of source code must retain the above copyright notice,
	* this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright notice,
	* this list of conditions and the following disclaimer in the documentation
	* and/or other materials provided with the distribution.
	* 3. The name of the author may not be used to endorse or promote products
	* derived from this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
	* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
	* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
	* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
	* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
	* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
	* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#include "talk/session/phone/testutils.h"

	#include <math.h>

	#ifdef HAVE_YUV
	#include "libyuv/compare.h"
	#endif
	#include "talk/base/bytebuffer.h"
	#include "talk/base/fileutils.h"
	#include "talk/base/gunit.h"
	#include "talk/base/pathutils.h"
	#include "talk/base/stream.h"
	#include "talk/base/stringutils.h"
	#include "talk/session/phone/rtpdump.h"
	#include "talk/session/phone/videocapturer.h"
	#include "talk/session/phone/videoframe.h"

	namespace cricket {

	/////////////////////////////////////////////////////////////////////////
	// Implementation of RawRtpPacket
	/////////////////////////////////////////////////////////////////////////
	void RawRtpPacket::WriteToByteBuffer(
	uint32 in_ssrc, talk_base::ByteBuffer *buf) const {
	if (!buf) return;

	buf->WriteUInt8(ver_to_cc);
	buf->WriteUInt8(m_to_pt);
	buf->WriteUInt16(sequence_number);
	buf->WriteUInt32(timestamp);
	buf->WriteUInt32(in_ssrc);
	buf->WriteBytes(payload, sizeof(payload));
	}

	bool RawRtpPacket::ReadFromByteBuffer(talk_base::ByteBuffer* buf) {
	if (!buf) return false;

	bool ret = true;
	ret &= buf->ReadUInt8(&ver_to_cc);
	ret &= buf->ReadUInt8(&m_to_pt);
	ret &= buf->ReadUInt16(&sequence_number);
	ret &= buf->ReadUInt32(&timestamp);
	ret &= buf->ReadUInt32(&ssrc);
	ret &= buf->ReadBytes(payload, sizeof(payload));
	return ret;
	}

	bool RawRtpPacket::SameExceptSeqNumTimestampSsrc(
	const RawRtpPacket& packet, uint16 seq, uint32 ts, uint32 ssc) const {
	return sequence_number == seq &&
	timestamp == ts &&
	ver_to_cc == packet.ver_to_cc &&
	m_to_pt == packet.m_to_pt &&
	ssrc == ssc &&
	0 == memcmp(payload, packet.payload, sizeof(payload));
	}

	/////////////////////////////////////////////////////////////////////////
	// Implementation of RawRtcpPacket
	/////////////////////////////////////////////////////////////////////////
	void RawRtcpPacket::WriteToByteBuffer(talk_base::ByteBuffer *buf) const {
	if (!buf) return;

	buf->WriteUInt8(ver_to_count);
	buf->WriteUInt8(type);
	buf->WriteUInt16(length);
	buf->WriteBytes(payload, sizeof(payload));
	}

	bool RawRtcpPacket::ReadFromByteBuffer(talk_base::ByteBuffer* buf) {
	if (!buf) return false;

	bool ret = true;
	ret &= buf->ReadUInt8(&ver_to_count);
	ret &= buf->ReadUInt8(&type);
	ret &= buf->ReadUInt16(&length);
	ret &= buf->ReadBytes(payload, sizeof(payload));
	return ret;
	}

	bool RawRtcpPacket::EqualsTo(const RawRtcpPacket& packet) const {
	return ver_to_count == packet.ver_to_count &&
	type == packet.type &&
	length == packet.length &&
	0 == memcmp(payload, packet.payload, sizeof(payload));
	}

	/////////////////////////////////////////////////////////////////////////
	// Implementation of class RtpTestUtility
	/////////////////////////////////////////////////////////////////////////
	const RawRtpPacket RtpTestUtility::kTestRawRtpPackets[] = {
	{0x80, 0, 0, 0, RtpTestUtility::kDefaultSsrc, "RTP frame 0"},
	{0x80, 0, 1, 30, RtpTestUtility::kDefaultSsrc, "RTP frame 1"},
	{0x80, 0, 2, 30, RtpTestUtility::kDefaultSsrc, "RTP frame 1"},
	{0x80, 0, 3, 60, RtpTestUtility::kDefaultSsrc, "RTP frame 2"}
	};
	const RawRtcpPacket RtpTestUtility::kTestRawRtcpPackets[] = {
	// The Version is 2, the Length is 2, and the payload has 8 bytes.
	{0x80, 0, 2, "RTCP0000"},
	{0x80, 0, 2, "RTCP0001"},
	{0x80, 0, 2, "RTCP0002"},
	{0x80, 0, 2, "RTCP0003"},
	};

	size_t RtpTestUtility::GetTestPacketCount() {
	return talk_base::_min(
	ARRAY_SIZE(kTestRawRtpPackets),
	ARRAY_SIZE(kTestRawRtcpPackets));
	}

	bool RtpTestUtility::WriteTestPackets(
	size_t count, bool rtcp, uint32 rtp_ssrc, RtpDumpWriter* writer) {
	if (!writer \|\| count > GetTestPacketCount()) return false;

	bool result = true;
	uint32 elapsed_time_ms = 0;
	for (size_t i = 0; i < count && result; ++i) {
	talk_base::ByteBuffer buf;
	if (rtcp) {
	kTestRawRtcpPackets[i].WriteToByteBuffer(&buf);
	} else {
	kTestRawRtpPackets[i].WriteToByteBuffer(rtp_ssrc, &buf);
	}

	RtpDumpPacket dump_packet(buf.Data(), buf.Length(), elapsed_time_ms, rtcp);
	elapsed_time_ms += kElapsedTimeInterval;
	result &= (talk_base::SR_SUCCESS == writer->WritePacket(dump_packet));
	}
	return result;
	}

	bool RtpTestUtility::VerifyTestPacketsFromStream(
	size_t count, talk_base::StreamInterface* stream, uint32 ssrc) {
	if (!stream) return false;

	uint32 prev_elapsed_time = 0;
	bool result = true;
	stream->Rewind();
	RtpDumpLoopReader reader(stream);
	for (size_t i = 0; i < count && result; ++i) {
	// Which loop and which index in the loop are we reading now.
	size_t loop = i / GetTestPacketCount();
	size_t index = i % GetTestPacketCount();

	RtpDumpPacket packet;
	result &= (talk_base::SR_SUCCESS == reader.ReadPacket(&packet));
	// Check the elapsed time of the dump packet.
	result &= (packet.elapsed_time >= prev_elapsed_time);
	prev_elapsed_time = packet.elapsed_time;

	// Check the RTP or RTCP packet.
	talk_base::ByteBuffer buf(reinterpret_cast<const char*>(&packet.data[0]),
	packet.data.size());
	if (packet.is_rtcp) {
	// RTCP packet.
	RawRtcpPacket rtcp_packet;
	result &= rtcp_packet.ReadFromByteBuffer(&buf);
	result &= rtcp_packet.EqualsTo(kTestRawRtcpPackets[index]);
	} else {
	// RTP packet.
	RawRtpPacket rtp_packet;
	result &= rtp_packet.ReadFromByteBuffer(&buf);
	result &= rtp_packet.SameExceptSeqNumTimestampSsrc(
	kTestRawRtpPackets[index],
	kTestRawRtpPackets[index].sequence_number +
	loop * GetTestPacketCount(),
	kTestRawRtpPackets[index].timestamp + loop * kRtpTimestampIncrease,
	ssrc);
	}
	}

	stream->Rewind();
	return result;
	}

	bool RtpTestUtility::VerifyPacket(const RtpDumpPacket* dump,
	const RawRtpPacket* raw,
	bool header_only) {
	if (!dump \|\| !raw) return false;

	talk_base::ByteBuffer buf;
	raw->WriteToByteBuffer(RtpTestUtility::kDefaultSsrc, &buf);

	if (header_only) {
	size_t header_len = 0;
	dump->GetRtpHeaderLen(&header_len);
	return header_len == dump->data.size() &&
	buf.Length() > dump->data.size() &&
	0 == memcmp(buf.Data(), &dump->data[0], dump->data.size());
	} else {
	return buf.Length() == dump->data.size() &&
	0 == memcmp(buf.Data(), &dump->data[0], dump->data.size());
	}
	}

	// Implementation of VideoCaptureListener.
	VideoCapturerListener::VideoCapturerListener(VideoCapturer* capturer)
	: start_result_(CR_PENDING),
	frame_count_(0),
	frame_fourcc_(0),
	frame_width_(0),
	frame_height_(0),
	frame_size_(0),
	resolution_changed_(false) {
	capturer->SignalStartResult.connect(this,
	&VideoCapturerListener::OnStartResult);
	capturer->SignalFrameCaptured.connect(this,
	&VideoCapturerListener::OnFrameCaptured);
	capturer->SignalCaptureEvent.connect(this,
	&VideoCapturerListener::OnCaptureEvent);
	}

	void VideoCapturerListener::OnStartResult(VideoCapturer* capturer,
	CaptureResult result) {
	start_result_ = result;
	}

	void VideoCapturerListener::OnFrameCaptured(VideoCapturer* capturer,
	const CapturedFrame* frame) {
	++frame_count_;
	if (1 == frame_count_) {
	frame_fourcc_ = frame->fourcc;
	frame_width_ = frame->width;
	frame_height_ = frame->height;
	frame_size_ = frame->data_size;
	} else if (frame_width_ != frame->width \|\| frame_height_ != frame->height) {
	resolution_changed_ = true;
	}
	}

	void VideoCapturerListener::OnCaptureEvent(VideoCapturer* capturer,
	CaptureEvent ev) {
	}


	// Returns the absolute path to a file in the testdata/ directory.
	std::string GetTestFilePath(const std::string& filename) {
	// Locate test data directory.
	talk_base::Pathname path = GetTalkDirectory();
	EXPECT_FALSE(path.empty()); // must be run from inside "talk"
	path.AppendFolder("session");
	path.AppendFolder("phone");
	path.AppendFolder("testdata");
	path.SetFilename(filename);
	return path.pathname();
	}

	// PSNR formula: psnr = 10 * log10 (Peak Signal^2 / mse)
	// sse is set to a small number for identical frames or sse == 0
	double ComputePSNR(double sse, double size) {
	if (sse <= 0.)
	sse = 65025.0 * size / pow(10., 128./10.); // produces max PSNR of 128
	return 10.0 * log10(65025.0 * size / sse);
	}

	double ComputeSumSquareError(const uint8 org, const uint8 rec, int size) {
	#ifdef HAVE_YUV
	return static_cast<double>(libyuv::ComputeSumSquareError(org, rec, size));
	#else
	double sse = 0.;
	for (int j = 0; j < size; ++j) {
	const int diff = static_cast<int>(org[j]) - static_cast<int>(rec[j]);
	sse += static_cast<double>(diff * diff);
	}
	return sse;
	#endif
	}

	// Loads the image with the specified prefix and size into \|out\|.
	bool LoadPlanarYuvTestImage(const std::string& prefix,
	int width, int height, uint8* out) {
	std::stringstream ss;
	ss << prefix << "." << width << "x" << height << "_P420.yuv";

	talk_base::scoped_ptr<talk_base::FileStream> stream(
	talk_base::Filesystem::OpenFile(talk_base::Pathname(
	GetTestFilePath(ss.str())), "rb"));
	if (!stream.get()) {
	return false;
	}

	talk_base::StreamResult res =
	stream->ReadAll(out, I420_SIZE(width, height), NULL, NULL);
	return (res == talk_base::SR_SUCCESS);
	}

	// Dumps the YUV image out to a file, for visual inspection.
	// PYUV tool can be used to view dump files.
	void DumpPlanarYuvTestImage(const std::string& prefix, const uint8* img,
	int w, int h) {
	talk_base::FileStream fs;
	char filename[256];
	talk_base::sprintfn(filename, sizeof(filename), "%s.%dx%d_P420.yuv",
	prefix.c_str(), w, h);
	fs.Open(filename, "wb", NULL);
	fs.Write(img, I420_SIZE(w, h), NULL, NULL);
	}

	// Dumps the ARGB image out to a file, for visual inspection.
	// ffplay tool can be used to view dump files.
	void DumpPlanarArgbTestImage(const std::string& prefix, const uint8* img,
	int w, int h) {
	talk_base::FileStream fs;
	char filename[256];
	talk_base::sprintfn(filename, sizeof(filename), "%s.%dx%d_ARGB.raw",
	prefix.c_str(), w, h);
	fs.Open(filename, "wb", NULL);
	fs.Write(img, ARGB_SIZE(w, h), NULL, NULL);
	}

	bool VideoFrameEqual(const VideoFrame* frame0, const VideoFrame* frame1) {
	const uint8* y0 = frame0->GetYPlane();
	const uint8* u0 = frame0->GetUPlane();
	const uint8* v0 = frame0->GetVPlane();
	const uint8* y1 = frame1->GetYPlane();
	const uint8* u1 = frame1->GetUPlane();
	const uint8* v1 = frame1->GetVPlane();

	for (size_t i = 0; i < frame0->GetHeight(); ++i) {
	if (0 != memcmp(y0, y1, frame0->GetWidth())) {
	return false;
	}
	y0 += frame0->GetYPitch();
	y1 += frame1->GetYPitch();
	}

	for (size_t i = 0; i < frame0->GetChromaHeight(); ++i) {
	if (0 != memcmp(u0, u1, frame0->GetChromaWidth())) {
	return false;
	}
	if (0 != memcmp(v0, v1, frame0->GetChromaWidth())) {
	return false;
	}
	u0 += frame0->GetUPitch();
	v0 += frame0->GetVPitch();
	u1 += frame1->GetUPitch();
	v1 += frame1->GetVPitch();
	}

	return true;
	}

	} // namespace cricket