基于Qt的摄像头采集数据和264编码，并写入本地文件，可播放

#include <fcntl.h> #include <unistd.h> #include <malloc.h> #include <sys/stat.h> #include <sys/types.h> #include <time.h> #include <sys/mman.h> #include <sys/ioctl.h> #include <stdlib.h> #include <string.h> #include <linux/videodev2.h> #include "video_capture.h" #include "h264encoder.h" #include <iostream> using namespace std; #define CLEAR(x) memset(&(x),0,sizeof(x)) typedef unsigned char uint8_t; char h264_file_name[100]="/myvideosave/myvideo.h264"; FILE *h264_fp; uint8_t *h264_buf; char yuv_file_name[100]="/myvideosave/myvideo.yuv"; FILE *yuv_fp; unsigned int n_buffers=0; Encoder en; int cnt=0; void open_camera(camera *cam) { cout<<"===>>open camera"<<endl; struct stat st; if(-1==stat(cam->device_name,&st)) { cout<<"Cannot identify device"<<endl; return; } if(!S_ISCHR(st.st_mode)) { cout<<cam->device_name<<" is no a device"<<endl; return; } cam->fd=open(cam->device_name,O_RDWR,0); if(-1==cam->fd) { cout<<"Cannot open "<<cam->device_name<<endl; return; } else cout<<"====>>camera open OK"<<endl; } void close_camera(camera *cam) { if(-1==close(cam->fd)) cout<<"Cannot close camera"<<endl; cam->fd=-1; } void init_file() { cout<<"====>>init file"<<endl; h264_fp=fopen(h264_file_name,"wa+"); yuv_fp=fopen(yuv_file_name,"wa+"); cout<<"====>>init file OK"<<endl; } void close_file() { fclose(h264_fp); fclose(yuv_fp); } void init_encoder(struct camera*cam) { cout<<"====>>init encoder"<<endl; compress_begin(&en,cam->width,cam->height); h264_buf=(uint8_t *)malloc(sizeof(uint8_t)*cam->width*cam->height*3); cout<<"====>>encoder init OK"<<endl; } void close_encoder() { compress_end(&en); free(h264_buf); h264_buf=NULL; } void encode_frame(uint8_t *yuv_frame,size_t yuv_length) { int h264_length=0; if(yuv_frame[0]=='\0') return; else cout<<"OK"<<endl; h264_length=compress_frame(&en,-1,yuv_frame,h264_buf); if(h264_length>0) fwrite(h264_buf,h264_length,1,h264_fp); else cout<<"h264_length error"<<endl; cout<<"h264_length :"<<h264_length<<endl; cout<<"yuv_length :"<<yuv_length<<endl<<endl; fwrite(yuv_frame,yuv_length,1,yuv_fp); } int read_and_encode_frame(camera *cam) { struct v4l2_buffer buf; cout<<"in read a frame"<<endl; CLEAR(buf); buf.type=V4L2_BUF_TYPE_VIDEO_CAPTURE; buf.memory=V4L2_MEMORY_MMAP; if(-1==ioctl(cam->fd,VIDIOC_DQBUF,&buf)) { cout<<"Cannot DQBUF"<<endl; return -1; } encode_frame(cam->buffers[buf.index].start,buf.length); if(-1==ioctl(cam->fd,VIDIOC_QBUF,&buf)) { cout<<"Cannot QBUF"<<endl; return -1; } return 1; } void start_capturing(camera *cam) { cout<<"====>>start capturing"<<endl; unsigned int i; enum v4l2_buf_type type; for(i=0;i<n_buffers;++i) { struct v4l2_buffer buf; CLEAR(buf); buf.type=V4L2_BUF_TYPE_VIDEO_CAPTURE; buf.memory=V4L2_MEMORY_MMAP; buf.index=i; if(-1==ioctl(cam->fd,VIDIOC_QBUF,&buf)) { cout<<"QBUF error"<<endl; return; } } type=V4L2_BUF_TYPE_VIDEO_CAPTURE; if(-1==ioctl(cam->fd,VIDIOC_STREAMON,&type)) { cout<<"Stream on error"<<endl; return; } cout<<"====>>start capturing OK"<<endl; } void stop_capturing(camera *cam) { enum v4l2_buf_type type; type=V4L2_BUF_TYPE_VIDEO_CAPTURE; if(-1==ioctl(cam->fd,VIDIOC_STREAMOFF,&type)) { cout<<"Stream off error"<<endl; return; } } void uninit_camera(camera *cam) { unsigned int i; for(i=0;i<n_buffers;++i) if(-1==munmap(cam->buffers[i].start,cam->buffers[i].length)) { cout<<"Munmap error"<<endl; return; } free(cam->buffers); cam->buffers=NULL; } void init_mmap(camera *cam) { cout<<"====>>init mmap"<<endl; struct v4l2_requestbuffers req; CLEAR(req); req.count=4; req.type=V4L2_BUF_TYPE_VIDEO_CAPTURE; req.memory=V4L2_MEMORY_MMAP; if(-1==ioctl(cam->fd,VIDIOC_REQBUFS,&req)) { cout<<"REQBUF error"<<endl; return; } if(req.count<2) { cout<<"Insufficient buffer memory on "<<cam->device_name<<endl; return; } cam->buffers=NULL; cam->buffers=(buffer *)calloc(req.count,sizeof(*(cam->buffers))); if(!cam->buffers) { cout<<"Out of memory"<<endl; return; } for(n_buffers=0;n_buffers<req.count;++n_buffers) { struct v4l2_buffer buf; CLEAR(buf); buf.type=V4L2_BUF_TYPE_VIDEO_CAPTURE; buf.memory=V4L2_MEMORY_MMAP; buf.index=n_buffers; if(-1==ioctl(cam->fd,VIDIOC_QUERYBUF,&buf)) { cout<<"mmap querybuf error"<<endl; return; } cam->buffers[n_buffers].length=buf.length; cam->buffers[n_buffers].start=(unsigned char *)mmap(NULL,buf.length,PROT_READ | PROT_WRITE,MAP_SHARED,cam->fd,buf.m.offset); if(MAP_FAILED==cam->buffers[n_buffers].start) { cout<<"mmap error"<<endl; return; } } cout<<"====>>init mmap OK"<<endl; } void init_camera(camera *cam) { cout<<"====>>init camera"<<endl; struct v4l2_capability *cap = &(cam->v4l2_cap); struct v4l2_cropcap *cropcap = &(cam->v4l2_cropcap); struct v4l2_crop *crop = &(cam->crop); struct v4l2_format *fmt = &(cam->v4l2_fmt); unsigned int min; if(-1==ioctl(cam->fd,VIDIOC_QUERYCAP,cap)) { cout<<"Cannot querycap"<<endl; return; } if((cap->capabilities & V4L2_CAP_VIDEO_CAPTURE)==0) { cout<<cam->device_name<<" is no video capture device"<<endl; return; } if(!(cap->capabilities & V4L2_CAP_STREAMING)) { cout<<cam->device_name<<" does not support streaming i/o"<<endl; return; } cout<<"VIDOOC_QUERYCAP information :"<<endl; cout<<"the camera driver is"<<cap->driver<<endl; cout<<"the camera card is "<<cap->card<<endl; cout<<"the camera bus info is "<<cap->bus_info<<endl; cout<<"the version is "<<cap->version<<endl; CLEAR(*cropcap); cropcap->type = V4L2_BUF_TYPE_VIDEO_CAPTURE; crop->c.width = cam->width; crop->c.height = cam->height; crop->c.left = 0; crop->c.top = 0; crop->type = V4L2_BUF_TYPE_VIDEO_CAPTURE; CLEAR(*fmt); fmt->type = V4L2_BUF_TYPE_VIDEO_CAPTURE; fmt->fmt.pix.width = cam->width; fmt->fmt.pix.height = cam->height; fmt->fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV; //yuv422 fmt->fmt.pix.field=V4L2_FIELD_INTERLACED; if(-1==ioctl(cam->fd,VIDIOC_S_FMT,fmt)) { cout<<"set fromat error"<<endl; return; } min=fmt->fmt.pix.width*2; if(fmt->fmt.pix.bytesperline<min) fmt->fmt.pix.bytesperline=min; min=fmt->fmt.pix.bytesperline*fmt->fmt.pix.height; if(fmt->fmt.pix.sizeimage<min) fmt->fmt.pix.sizeimage=min; init_mmap(cam); cout<<"====>>init camera OK"<<endl; } void v4l2_init(camera *cam) { cout<<"====>>v4l2 init"<<endl; open_camera(cam); init_camera(cam); start_capturing(cam); init_encoder(cam); init_file(); cout<<"====>>v4l2_init OK"<<endl; } void v4l2_close(camera *cam) { cout<<"===>>v4l2_closing"<<endl; stop_capturing(cam); uninit_camera(cam); close_camera(cam); free(cam); close_file(); close_encoder(); cout<<"v4l2 close completed"<<endl; }