基于QCamera, QTcpServer实现网络视频监控

/* author: blog.csdn.net/jklinux */ #include "mywin.h" #include "ui_mywin.h" #include <QMessageBox> #include <QScreen> #include <QBuffer> #define W 640 #define H 480 #define LEN (W*H*2) #define P_LEN 1380 class Data { public: char data[LEN]; //图像数据 int len; //图像大小 int len_sent; //已发出的数据长度 int stats; //工作状态, 0表示空闲(图像数据可以更新), 1表示图像数据传输中(还不可以更新图像数据), 2表示需要发出图像数据的第一部分 Data() { len_sent = 0; stats = 0; } }; MyWin::MyWin(QWidget *parent) : QWidget(parent), ui(new Ui::MyWin) { ui->setupUi(this); server = new QTcpServer(this); if (!server->listen(QHostAddress::Any, 12345)) { QMessageBox::critical(this, "error", "listen port failed"); exit(0); } connect(server, SIGNAL(newConnection()), this, SLOT(new_client())); cam = new QCamera; view = new QCameraViewfinder(this); view->setGeometry(0, 0, W, H); view->show(); cam->setViewfinder(view); cam->start(); timer = new QTimer(this); connect(timer, SIGNAL(timeout()), this, SLOT(timer_slot())); timer->start(100); resize(640, 600); } MyWin::~MyWin() { delete ui; cam->stop(); delete cam; delete view; delete server; } void MyWin::timer_slot() { QString s("newImage:%1"); QScreen *screen = QApplication::primaryScreen(); QPixmap map = screen->grabWindow(view->winId()); //只截view窗口对象上的图像，也就是摄像头的数据 //再编码成jpg图像 QByteArray ba; QBuffer bf(&ba); map.save(&bf, "jpg", 50); //给每个QTcpSocket对象更新图像数据 for (int i = 0; i < clients.size(); i++) { Data *d = (Data*)clients.at(i)->userData(0); if (d->stats != 1) // 1表示传输中 { memcpy(d->data, ba.data(), ba.size()); d->len = ba.size(); if (d->stats == 2) { d->stats = 1; //改为传输中的状态 d->len_sent = 0; clients.at(i)->write(s.arg(d->len).toUtf8()); } } } } void MyWin::read_data() { QTcpSocket *client = qobject_cast<QTcpSocket *>(sender()); QString str = client->readAll(); Data *d = (Data*)client->userData(0); QString s("newImage:%1"); if (str == "new_request") { if ((d->len) && (d->stats==0)) //图像大小不为0，表示已更新图像数据了 { d->stats = 1; client->write(s.arg(d->len).toUtf8()); d->len_sent = 0; } else //图像数据还没有更新 d->stats = 2; //在定时器的槽函数里发出"newImage..." } if (str == "ack") { int len_send = P_LEN; if (d->len_sent >= d->len) //如果图像已传输完毕 return; if ((d->len_sent + P_LEN) > d->len) len_send = d->len - d->len_sent; d->len_sent += client->write(d->data+d->len_sent, len_send); if (d->len_sent >= d->len) { d->stats = 0; //传输完毕后，把状态改为可更新 d->len = 0; } } } void MyWin::distconnect_client() { QTcpSocket *client = qobject_cast<QTcpSocket *>(sender()); Data *d = (Data*)client->userData(0); clients.removeOne(client); } void MyWin::new_client() { QTcpSocket *client = server->nextPendingConnection(); connect(client, SIGNAL(disconnected()), this, SLOT(distconnect_client())); connect(client, SIGNAL(readyRead()), this, SLOT(read_data())); client->setUserData(0, (QObjectUserData *)new Data); clients.append(client); }