基于v4l2视频采集和传输

#include "my.h" int main() { char buff[1024]; client_fd = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP); if(client_fd < 0){ perror("socket"); exit(EXIT_FAILURE); } struct sockaddr_in server_addr; memset(&server_addr,0,sizeof(server_addr)); server_addr.sin_family = AF_INET; server_addr.sin_port = htons(7777); server_addr.sin_addr.s_addr = inet_addr("10.5.19.10"); int ret = connect(client_fd,(struct sockaddr *)&server_addr,sizeof(struct sockaddr)); if(ret < 0){ perror("connect"); exit(EXIT_FAILURE); } pthread_mutex_init(&mut,NULL); pthread_cond_init(&image_cond,NULL); pthread_cond_init(&info_cond,NULL); memset(&recv_thread,0,sizeof(image_thread)); if((ret = pthread_create(&recv_thread,NULL,recv_thread_function,(void *)&client_fd)) != 0) printf("revb_thread create error\n"); else printf("recv_thread create success\n"); memset(&image_thread,0,sizeof(image_thread)); if((ret = pthread_create(&image_thread,NULL,image_thread_function,(void *)&client_fd)) != 0) printf("image_thread create error\n"); else printf("image_thread create success\n"); memset(&info_thread,0,sizeof(image_thread)); if((ret = pthread_create(&info_thread,NULL,info_thread_function,(void *)&client_fd)) != 0) printf("info_thread create error\n"); else printf("info_thread create success\n"); pthread_join(recv_thread,NULL); pthread_join(image_thread,NULL); pthread_join(info_thread,NULL); close(client_fd); } void *recv_thread_function(void *arg) { int fd = *(int *)arg; char buff[1024]; struct sockaddr_in server_addr; memset(&server_addr,0,sizeof(server_addr)); int len = sizeof(struct sockaddr); while(1){ FD_ZERO(&read_fds); FD_SET(client_fd,&read_fds); max_fds = client_fd + 1; if((select(max_fds,&read_fds,NULL,NULL,NULL))<0){ perror("select"); exit(EXIT_FAILURE); } if(FD_ISSET(client_fd,&read_fds)){ memset(buff,0,sizeof(buff)); recv(client_fd,buff,sizeof(buff),0); if(strcmp(buff,"image_start") == 0){ pthread_mutex_lock(&mut); image_flag = 1; pthread_cond_signal(&image_cond); pthread_mutex_unlock(&mut); } else if(strcmp(buff,"image_end") == 0){ image_flag = 0; v4l2_video_off(); v4l2_munmap(); } else if(strcmp(buff,"cpu_info") == 0){ pthread_mutex_lock(&mut); info_flag = 1; pthread_cond_signal(&info_cond); pthread_mutex_unlock(&mut); } } } } void *image_thread_function(void *arg) { int fd = *(int *)arg; v4l2_open(); v4l2_get_capability(); v4l2_support_format(); set_v4l2_format(); set_v4l2_streamparm(); v4l2_init_mmap(); v4l2_video_on(); while(1){ pthread_mutex_lock(&mut); if(image_flag != 1) pthread_cond_wait(&image_cond,&mut); else{ //采集视频并传输 grap_video_loop(); image_flag = 0; } pthread_mutex_unlock(&mut); } } void *info_thread_function(void *arg) { int fd = *(int *)arg; struct dev_info dev; while(1){ memset(&dev,0,sizeof(dev)); pthread_mutex_lock(&mut); if(info_flag != 1) pthread_cond_wait(&info_cond,&mut); else{ //采集设备信息 get_devinfo(&dev); //send 设备信息 send(client_fd,(char *)&dev,sizeof(dev),0); info_flag = 0; } pthread_mutex_unlock(&mut); } } void v4l2_open() { if((fd = open("/dev/video0",O_RDWR)) < 0){ perror("v4l2 open error\n"); exit(EXIT_FAILURE); } } void v4l2_get_capability() { struct v4l2_capability cap; if(ioctl(fd,VIDIOC_QUERYCAP,&cap)<0){ perror("v4l2 get capability error\n"); exit(EXIT_FAILURE); } // printf("drive name %s\n",cap.driver); // printf("dev name %s\n",cap.card); } void v4l2_support_format() { struct v4l2_fmtdesc fmtdesc; memset(&fmtdesc,0,sizeof(fmtdesc)); fmtdesc.index = 0; fmtdesc.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; while((ioctl(fd,VIDIOC_ENUM_FMT,&fmtdesc)) == 0) fmtdesc.index++; // printf("pixelformat = %c%c%c%c\n",fmtdesc.pixelformat & 0xff,(fmtdesc.pixelformat >> 8)&0xff,(fmtdesc.pixelformat >> 16)&0xff,(fmtdesc.pixelformat >> 24)&0xff); // printf("description %s\n",fmtdesc.description); } int set_v4l2_streamparm() { struct v4l2_streamparm parm; memset(&parm,0,sizeof(parm)); parm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; if(ioctl(fd,VIDIOC_G_PARM,&parm)<0){ perror("v4l2 get parm error\n"); exit(EXIT_FAILURE); } printf("denominator %d\n",parm.parm.capture.timeperframe.denominator); parm.parm.capture.timeperframe.numerator = 1; parm.parm.capture.timeperframe.denominator = 30; parm.parm.capture.capturemode = 0; //设置为高清 if(ioctl(fd,VIDIOC_S_PARM,&parm)<0){ perror("v4l2 set parm error\n"); exit(EXIT_FAILURE); } return 0; } int set_v4l2_format() { struct v4l2_format fmt; memset(&fmt,0,sizeof(fmt)); fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; if(ioctl(fd,VIDIOC_G_FMT,&fmt)<0){ perror("v4l2 get format error\n"); exit(EXIT_FAILURE); } fmt.fmt.pix.width = 320; fmt.fmt.pix.height = 240; fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_MJPEG; fmt.fmt.pix.field = V4L2_FIELD_INTERLACED; if(ioctl(fd,VIDIOC_S_FMT,&fmt)<0){ perror("v4l2 set format error\n"); exit(EXIT_FAILURE); } if(ioctl(fd,VIDIOC_G_FMT,&fmt)<0){ perror("v4l2 get format error\n"); exit(EXIT_FAILURE); } return 0; } int v4l2_init_mmap() { struct v4l2_requestbuffers req; struct v4l2_buffer buf; memset(&req,0,sizeof(req)); req.count = 4; req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; req.memory = V4L2_MEMORY_MMAP; if(ioctl(fd,VIDIOC_REQBUFS,&req) < 0){ perror("v4l2 local memory error\n"); exit(EXIT_FAILURE); } buffers = calloc(req.count,sizeof(VideoBuffer)); for(numBufs=0;numBufs<req.count;numBufs++) { memset(&buf,0,sizeof(buf)); buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; buf.memory = V4L2_MEMORY_MMAP; buf.index = numBufs; //读取缓存 if(ioctl(fd,VIDIOC_QUERYBUF,&buf) < 0){ perror("v4l2 VIDIOC_QUERYBUF error\n"); exit(EXIT_FAILURE); } buffers[numBufs].length = buf.length; //转换成相对地址 buffers[numBufs].start = mmap(NULL,buf.length,PROT_READ|PROT_WRITE,MAP_SHARED,fd,buf.m.offset); } return 0; } int v4l2_grab_frame() { struct v4l2_buffer buf; memset(&buf,0,sizeof(buf)); buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; buf.memory = V4L2_MEMORY_MMAP; //读取缓存 if(ioctl(fd,VIDIOC_DQBUF,&buf) < 0){ perror("v4l2 VIDIOC_DQBUF error\n"); exit(EXIT_FAILURE); } assert(buf.index < numBufs); process_video_image(buffers[buf.index].start,buffers[buf.index].length); //重新加入缓存队列 if(ioctl(fd,VIDIOC_QBUF,&buf) < 0){ perror("v4l2 VIDIOC_QBUF error\n"); exit(EXIT_FAILURE); } return 1; } int v4l2_video_on() { unsigned int i; enum v4l2_buf_type type; for(i=0;i<4;i++){ struct v4l2_buffer buf; memset(&buf,0,sizeof(buf)); buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; buf.memory = V4L2_MEMORY_MMAP; buf.index = i; if(ioctl(fd,VIDIOC_QBUF,&buf) < 0){ perror("v4l2 VIDIOC_QBUF error\n"); exit(EXIT_FAILURE); } } type = V4L2_BUF_TYPE_VIDEO_CAPTURE; if(ioctl(fd,VIDIOC_STREAMON,&type) < 0){ perror("v4l2 VIDIOC_STREAMON error\n"); exit(EXIT_FAILURE); } printf("video on\n"); return 0; } void process_video_image(void *p,unsigned int size) { //发送给服务器 int nsendbytes = send(client_fd,p,size,0); printf("send ok\n"); } void grap_video_loop() { while(1){ fd_set fds; struct timeval tv; int ret; FD_ZERO(&fds); FD_SET(fd,&fds); if((ret=select(fd+1,&fds,NULL,NULL,NULL))<0){ perror("select\n"); exit(EXIT_FAILURE); } if(v4l2_grab_frame()) break; } } int v4l2_video_off() { enum v4l2_buf_type type; type = V4L2_BUF_TYPE_VIDEO_CAPTURE; if(ioctl(fd,VIDIOC_STREAMOFF,&type) < 0){ perror("v4l2 VIDIOC_STREAMON error\n"); exit(EXIT_FAILURE); } } void v4l2_munmap() { for(numBufs=0;numBufs<4;numBufs++) { munmap(buffers[numBufs].start,buffers[numBufs].length); } close(fd); } void get_devinfo(struct dev_info *dev) { float