毕设新项目-基于C语言QT+v4l2+OpenCV+sqlite的视频监控系统源码+项目说明.zip

#include "v4l2api.h" #include <QDebug> #include <QImage> #include <jpeglib.h> V4l2Api::V4l2Api(const char *dname, int count) : deviceName(dname), count(count) { this->open(); } V4l2Api::~V4l2Api() { this->close(); } void V4l2Api::open() { video_init(); video_mmap(); #if 1 //开始采集 enum v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE; int ret = ioctl(this->vfd, VIDIOC_STREAMON, &type); if (ret < 0) { perror("start fail"); } #endif } void V4l2Api::close() { enum v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE; int ret = ioctl(this->vfd, VIDIOC_STREAMOFF, &type); if (ret < 0) { perror("stop fail"); } //释放映射 for (int i = 0; i < this->framebuffers.size(); i++) { munmap(framebuffers.at(i).start, framebuffers.at(i).length); } } void V4l2Api::grapImage(char *imageBuffer, int *length) { // select (rfds, wfds, efds, time) struct v4l2_buffer readbuf; readbuf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; readbuf.memory = V4L2_MEMORY_MMAP; // perror("read"); if (ioctl(this->vfd, VIDIOC_DQBUF, &readbuf) < 0) //取一针数据 { perror("read image fail"); } printf("%ld\n", readbuf.length); *length = readbuf.length; memcpy(imageBuffer, framebuffers[readbuf.index].start, framebuffers[readbuf.index].length); //把用完的队列空间放回队列中重复使用 if (ioctl(vfd, VIDIOC_QBUF, &readbuf) < 0) { perror("destroy fail"); exit(1); } } void V4l2Api::video_init() { // 1.打开设备 this->vfd = ::open(deviceName.c_str(), O_RDWR); if (this->vfd < 0) { perror("open fail"); VideoException vexp("open fail"); //创建异常对象 //抛异常 throw vexp; } // 2.配置采集属性 struct v4l2_format vfmt; vfmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; // vfmt.fmt.pix.width = WIDTH; vfmt.fmt.pix.height = HEIGHT; vfmt.fmt.pix.pixelformat = V4L2_PIX_FMT_JPEG; //（设置视频输出格式，但是要摄像头支持4:2:2） //通过ioctl把属性写入设备 int ret = ioctl(this->vfd, VIDIOC_S_FMT, &vfmt); if (ret < 0) { perror("set fail"); // VideoException vexp("set fail");//创建异常对象 // throw vexp; } //通过ioctl从设备获取属性 memset(&vfmt, 0, sizeof(vfmt)); vfmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; ret = ioctl(this->vfd, VIDIOC_G_FMT, &vfmt); if (ret < 0) { perror("get fail"); // VideoException vexp("get fail");//创建异常对象 // throw vexp; } if (vfmt.fmt.pix.width == WIDTH && vfmt.fmt.pix.height == HEIGHT && vfmt.fmt.pix.pixelformat == V4L2_PIX_FMT_JPEG) { } else { // VideoException vexp("set error 2");//创建异常对象 // throw vexp; } } void V4l2Api::video_mmap() { // 1申请缓冲区队列 struct v4l2_requestbuffers reqbuffer; reqbuffer.count = this->count; //申请缓冲区队列长度 reqbuffer.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; reqbuffer.memory = V4L2_MEMORY_MMAP; int ret = ioctl(this->vfd, VIDIOC_REQBUFS, &reqbuffer); if (ret < 0) { perror("req buffer fail"); // VideoException vexp("req buffer fail");//创建异常对象 // throw vexp; } // 2.映射 for (int i = 0; i < this->count; i++) { struct VideoFrame frame; struct v4l2_buffer mapbuffer; mapbuffer.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; mapbuffer.index = i; mapbuffer.memory = V4L2_MEMORY_MMAP; //从队列中拿到内核空间 ret = ioctl(this->vfd, VIDIOC_QUERYBUF, &mapbuffer); if (ret < 0) { perror("query fail"); } //映射 frame.length = mapbuffer.length; frame.start = (char *)mmap(NULL, mapbuffer.length, PROT_READ | PROT_WRITE, MAP_SHARED, this->vfd, mapbuffer.m.offset); //空间放回队列中（内核空间） ret = ioctl(this->vfd, VIDIOC_QBUF, &mapbuffer); //把frame添加到容器framebuffers framebuffers.push_back(frame); } } bool V4l2Api::yuyv_to_rgb888(unsigned char *yuyvdata, unsigned char *rgbdata, int picw, int pich) { int i, j; unsigned char y1, y2, u, v; int r1, g1, b1, r2, g2, b2; //确保所转的数据或要保存的地址有效 if (yuyvdata == NULL || rgbdata == NULL) { return false; } int tmpw = picw / 2; for (i = 0; i < pich; i++) { for (j = 0; j < tmpw; j++) // 640/2 == 320 { // yuv422 // R = 1.164*(Y-16) + 1.159*(V-128); // G = 1.164*(Y-16) - 0.380*(U-128)+ 0.813*(V-128); // B = 1.164*(Y-16) + 2.018*(U-128)); //下面的四个像素为：[Y0 U0 V0] [Y1 U1 V1] -------------[Y2 U2 V2] [Y3 U3 // V3] //存放的码流为： Y0 U0 Y1 V1------------------------Y2 U2 Y3 V3 //映射出像素点为： [Y0 U0 V1] [Y1 U0 V1]--------------[Y2 U2 V3] [Y3 U2 // V3] //获取每个像素yuyv数据 YuYv y1 = *(yuyvdata + (i * tmpw + j) * 4); // yuv像素的Y u = *(yuyvdata + (i * tmpw + j) * 4 + 1); // yuv像素的U y2 = *(yuyvdata + (i * tmpw + j) * 4 + 2); v = *(yuyvdata + (i * tmpw + j) * 4 + 3); //把yuyv数据转换为rgb数据 r1 = y1 + 1.042 * (v - 128); g1 = y1 - 0.34414 * (u - 128); b1 = y1 + 1.772 * (u - 128); r2 = y2 + 1.042 * (v - 128); g2 = y2 - 0.34414 * (u - 128); b2 = y2 + 1.772 * (u - 128); if (r1 > 255) r1 = 255; else if (r1 < 0) r1 = 0; if (g1 > 255) g1 = 255; else if (g1 < 0) g1 = 0; if (b1 > 255) b1 = 255; else if (b1 < 0) b1 = 0; if (r2 > 255) r2 = 255; else if (r2 < 0) r2 = 0; if (g2 > 255) g2 = 255; else if (g2 < 0) g2 = 0; if (b2 > 255) b2 = 255; else if (b2 < 0) b2 = 0; //把rgb值保存于rgb空间 数据为反向 rgbdata[((pich - 1 - i) * tmpw + j) * 6] = (unsigned char)b1; rgbdata[((pich - 1 - i) * tmpw + j) * 6 + 1] = (unsigned char)g1; rgbdata[((pich - 1 - i) * tmpw + j) * 6 + 2] = (unsigned char)r1; rgbdata[((pich - 1 - i) * tmpw + j) * 6 + 3] = (unsigned char)b2; rgbdata[((pich - 1 - i) * tmpw + j) * 6 + 4] = (unsigned char)g2; rgbdata[((pich - 1 - i) * tmpw + j) * 6 + 5] = (unsigned char)r2; } } return true; } void V4l2Api::jpeg_to_rgb888(unsigned char *jpegData, int size, unsigned char *rgbdata) { //解码jpeg图片 // 1.定义解码对象struct jpeg_decompress_struct 错误处理对象struct // jpeg_error_mgr; struct jpeg_decompress_struct cinfo; struct jpeg_error_mgr err; // 2.初始化错误jpeg_std_error(err)，创建初始化解码对象jpeg_create_decompress(); cinfo.err = jpeg_std_error(&err); jpeg_create_decompress(&cinfo); // 3.加载源数据jpeg_mem_src() jpeg_mem_src(&cinfo, jpegData, size); // 4.获取jpeg图片头数据 jpeg_read_header(&cinfo, true); // 5.开始解码 jpeg_start_decompress(&cinfo); // 6.分配存储一行像素所需要的空间//---RGB数据 // 640--cinfo.output_width, 480--cinfo.output_height char *rowFrame = (char *)malloc(cinfo.output_width * 3); int pos = 0; // 7.一行一行循环读取（一次读取一行，要全部读完） while (cinfo.output_scanline < cinfo.output_height) { //读取一行数据--解码一行 jpeg_read_scanlines(&cinfo, (JSAMPARRAY)&rowFrame, 1); //把rgb像素显示在lcd上 mmp memcpy(rgbdata + pos, rowFrame, cinfo.output_width * 3); pos += cinfo.output_width * 3; } free(rowFrame); // 8.解码完成 jpeg_finish_decompress(&cinfo); // 9.销毁解码对象 jpeg_destroy_decompress(&cinfo); } void V4l2Api::run() { isRunning = true; char buffer[WIDTH*HEIGHT*3]; char rgbbuffer[WIDTH*HEIGHT*3]; int times = 0; int len; while(isRunning) { grapImage(buffer, &len); //yuyv_to_rgb888((unsigned char *)buffer, (unsigned char *)rgbbuffer);