WebRtc libjingle_PeerConnection层（一） 显示本地视频

只做本地显示，在PeerConnection层调用流程比较简单。代码由Peerconnection_Client扣出来的。

1. 获得摄像头

cricket::VideoCapturer* OpenVideoCaptureDevice()

2. 设置Render

StartLocalRenderer(video_track);

3. 取并显示

//#include "talk/examples/peerconnection/client/conductor.h"#include <utility>#include <vector>#ifdef WIN32#include <Windows.h>#endif//#include "opencv2\opencv.hpp"#include "talk/app/webrtc/videosourceinterface.h"#include "talk/app/webrtc/mediastreaminterface.h"#include "talk/app/webrtc/peerconnectioninterface.h"#include "talk/media/devices/devicemanager.h"//#include "talk/app/webrtc/test/fakeconstraints.h"#include "talk/media/base/videorenderer.h"#include "talk/media/base/videoframe.h"#include "webrtc/base/common.h"#include "webrtc/base/json.h"#include "webrtc/base/logging.h"//#pragma comment(lib, "opencv_world300d.lib")#define DTLS_ON  true#define DTLS_OFF false// Names used for a IceCandidate JSON object.const char kCandidateSdpMidName[] = "sdpMid";const char kCandidateSdpMlineIndexName[] = "sdpMLineIndex";const char kCandidateSdpName[] = "candidate";// Names used for a SessionDescription JSON object.const char kSessionDescriptionTypeName[] = "type";const char kSessionDescriptionSdpName[] = "sdp";const char kAudioLabel[] = "audio_label";const char kVideoLabel[] = "video_label";const char kStreamLabel[] = "stream_label";// A little helper class to make sure we always to proper locking and// unlocking when working with VideoRenderer buffers.template <typename T>class AutoLock {public:explicit AutoLock(T* obj) : obj_(obj) { obj_->Lock(); }~AutoLock() { obj_->Unlock(); }protected:T* obj_;};class VideoRenderer : public webrtc::VideoRendererInterface {public:VideoRenderer(HWND wnd, int width, int height,webrtc::VideoTrackInterface* track_to_render);virtual ~VideoRenderer();void Lock() {::EnterCriticalSection(&buffer_lock_);}void Unlock() {::LeaveCriticalSection(&buffer_lock_);}// VideoRendererInterface implementationvirtual void SetSize(int width, int height);virtual void RenderFrame(const cricket::VideoFrame* frame);const BITMAPINFO& bmi() const { return bmi_; }const uint8* image() const { return image_.get(); }protected:enum {SET_SIZE,RENDER_FRAME,};HWND wnd_;BITMAPINFO bmi_;rtc::scoped_ptr<uint8[]> image_;CRITICAL_SECTION buffer_lock_;rtc::scoped_refptr<webrtc::VideoTrackInterface> rendered_track_;};//// VideoRenderer//VideoRenderer::VideoRenderer(HWND wnd, int width, int height,webrtc::VideoTrackInterface* track_to_render): wnd_(wnd), rendered_track_(track_to_render) {::InitializeCriticalSection(&buffer_lock_);ZeroMemory(&bmi_, sizeof(bmi_));bmi_.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);bmi_.bmiHeader.biPlanes = 1;bmi_.bmiHeader.biBitCount = 32;bmi_.bmiHeader.biCompression = BI_RGB;bmi_.bmiHeader.biWidth = width;bmi_.bmiHeader.biHeight = -height;bmi_.bmiHeader.biSizeImage = width * height *(bmi_.bmiHeader.biBitCount >> 3);rendered_track_->AddRenderer(this);}VideoRenderer::~VideoRenderer() {rendered_track_->RemoveRenderer(this);::DeleteCriticalSection(&buffer_lock_);}void VideoRenderer::SetSize(int width, int height) {AutoLock<VideoRenderer> lock(this);if (width == bmi_.bmiHeader.biWidth && height == bmi_.bmiHeader.biHeight) {return;}bmi_.bmiHeader.biWidth = width;bmi_.bmiHeader.biHeight = -height;bmi_.bmiHeader.biSizeImage = width * height *(bmi_.bmiHeader.biBitCount >> 3);image_.reset(new uint8[bmi_.bmiHeader.biSizeImage]);}int ii = 0;void VideoRenderer::RenderFrame(const cricket::VideoFrame* video_frame) {if (!video_frame)return;{AutoLock<VideoRenderer> lock(this);const cricket::VideoFrame* frame =video_frame->GetCopyWithRotationApplied();SetSize(static_cast<int>(frame->GetWidth()),static_cast<int>(frame->GetHeight()));ASSERT(image_.get() != NULL);frame->ConvertToRgbBuffer(cricket::FOURCC_ARGB,image_.get(),bmi_.bmiHeader.biSizeImage,bmi_.bmiHeader.biWidth *bmi_.bmiHeader.biBitCount / 8);}InvalidateRect(wnd_, NULL, TRUE);}rtc::scoped_refptr<webrtc::PeerConnectionInterface> peer_connection_;rtc::scoped_refptr<webrtc::PeerConnectionFactoryInterface> peer_connection_factory_;rtc::scoped_ptr<VideoRenderer> local_renderer_;HWND wnd = NULL;cricket::VideoCapturer* OpenVideoCaptureDevice() {rtc::scoped_ptr<cricket::DeviceManagerInterface> dev_manager(cricket::DeviceManagerFactory::Create());if (!dev_manager->Init()) {LOG(LS_ERROR) << "Can't create device manager";return NULL;}std::vector<cricket::Device> devs;if (!dev_manager->GetVideoCaptureDevices(&devs)) {LOG(LS_ERROR) << "Can't enumerate video devices";return NULL;}std::vector<cricket::Device>::iterator dev_it = devs.begin();cricket::VideoCapturer* capturer = NULL;for (; dev_it != devs.end(); ++dev_it) {capturer = dev_manager->CreateVideoCapturer(*dev_it);if (capturer != NULL)break;}return capturer;}void StartLocalRenderer(webrtc::VideoTrackInterface* local_video) {local_renderer_.reset(new VideoRenderer(wnd, 1, 1, local_video));}void AddStreams() {rtc::scoped_refptr<webrtc::AudioTrackInterface> audio_track(peer_connection_factory_->CreateAudioTrack(kAudioLabel, peer_connection_factory_->CreateAudioSource(NULL)));rtc::scoped_refptr<webrtc::VideoTrackInterface> video_track(peer_connection_factory_->CreateVideoTrack(kVideoLabel,peer_connection_factory_->CreateVideoSource(OpenVideoCaptureDevice(),NULL)));StartLocalRenderer(video_track);}bool InitializePeerConnection() {ASSERT(peer_connection_factory_.get() == NULL);ASSERT(peer_connection_.get() == NULL);peer_connection_factory_ = webrtc::CreatePeerConnectionFactory();if (!peer_connection_factory_.get()) {return false;}AddStreams();return peer_connection_.get() != NULL;}void Show(){VideoRenderer* local_renderer = local_renderer_.get();if (local_renderer){AutoLock<VideoRenderer> local_lock(local_renderer);const BITMAPINFO& bmi = local_renderer->bmi();const uint8* image = local_renderer->image();//printf("height=%d  width=%d  biSizeImage=%d \n", bmi.bmiHeader.biHeight, bmi.bmiHeader.biWidth, bmi.bmiHeader.biSizeImage);//GetBitmapFromScreen("c:\\aa.bmp", (BITMAPINFO)bmi, (uint8*)image);int rows = abs(bmi.bmiHeader.biHeight);;int cols = bmi.bmiHeader.biWidth;static int i = 0;printf("%d\n", i++);//cv::Mat img(rows, cols, CV_8UC4, (void*)image, 0U);//cv::imshow("Video Capture", img);//cvWaitKey(1);}}void ThreadProc(LPVOID lpParam){while (true){Show();Sleep(33);}}int main(){getchar();//wnd = FindWindow(L"ConsoleWindowClass", NULL);if (!InitializePeerConnection())printf("error\n");DWORD dwThreadId;CreateThread(NULL,//defaultsecurityattributes0,//usedefaultstacksize(LPTHREAD_START_ROUTINE)ThreadProc,//threadfunctionNULL,//argumenttothreadfunction0,//usedefaultcreationflags&dwThreadId);//returnsthethreadidentifiergetchar();return 0;}