rh9 环境下实现linux视频的捕获，并存为bmp格式。
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| /****************************************************/ /* */ /* v4lgrab.h */ /* */ /****************************************************/
#ifndef __V4LGRAB_H__ #define __V4LGRAB_H__
#include <stdio.h>
//typedef enum { FALSE = 0, TRUE = 1, OK = 2} BOOL;
//#define SWAP_HL_WORD(x) {(x) = ((x)<<8) | ((x)>>8);} //#define SWAP_HL_DWORD(x) {(x) = ((x)<<24) | ((x)>>24) | (((x)&0xff0000)>>8) | (((x)&0xff00)<<8);}
#define FREE(x) if((x)){free((x));(x)=NULL;}
typedef unsigned char BYTE; typedef unsigned shortWORD; typedef unsigned long DWORD; /* #pragma pack(1) typedef struct tagBITMAPFILEHEADER{ WORDbfType; // the flag of bmp, value is "BM" DWORD bfSize; // size BMP file ,unit is bytes DWORD bfReserved; // 0 DWORD bfOffBits; // must be 54 }BITMAPFILEHEADER;
typedef struct tagBITMAPINFOHEADER{ DWORD biSize; // must be 0x28 DWORD biWidth; // DWORD biHeight; // WORDbiPlanes; // must be 1 WORDbiBitCount; // DWORD biCompression; // DWORD biSizeImage; // DWORD biXPelsPerMeter; // DWORD biYPelsPerMeter; // DWORD biClrUsed; // DWORD biClrImportant; // }BITMAPINFOHEADER;
typedef struct tagRGBQUAD{ BYTE rgbBlue; BYTErgbGreen; BYTErgbRed; BYTErgbReserved; }RGBQUAD; */
#if defined(__cplusplus) extern "C" { /* Make sure we have C-declarations in C++ programs */ #endif
//if successful return 1,or else return 0 int openVideo(); int closeVideo();
//data 用来存储数据的空间, size空间大小 void getVideoData(unsigned char *data, int size);
#if defined(__cplusplus) } #endif
#endif //__V4LGRAB_H___
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/****************************************************/ /* */ /* v4lgrab.c */ /* */ /****************************************************/ #include <unistd.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <stdio.h> #include <sys/ioctl.h> #include <stdlib.h>
#include <linux/types.h> #include <linux/videodev.h>
#include "v4lgrab.h"
#define TRUE 1 #define FALSE 0
#define WIDTHBYTES(i) ((i+31)/32*4) #define FILE_VIDEO"/dev/video0" //#define BMP "image.bmp" #define IMAGEWIDTH 176 #define IMAGEHEIGHT 144
static int fd; static struct video_capability cap; static struct video_window win; static struct video_picture vpic;
int openVideo() { //Open video device fd = open(FILE_VIDEO, O_RDONLY); if (fd < 0) { perror(FILE_VIDEO); return (FALSE); }
//Get capabilities if (ioctl(fd, VIDIOCGCAP, &cap) < 0) { perror("VIDIOGCAP"); printf("(" FILE_VIDEO " not a video4linux device?)/n"); close(fd); return (FALSE); }
//Get the video overlay window if (ioctl(fd, VIDIOCGWIN, &win) < 0) { perror("VIDIOCGWIN"); close(fd); return (FALSE); }
//Set the video overlay window win.width = IMAGEWIDTH; win.height = IMAGEHEIGHT; if(ioctl(fd, VIDIOCSWIN, &win) <0) { perror("VIDIOCSWIN"); close(fd); return (FALSE);; }
//Get picture properties if (ioctl(fd, VIDIOCGPICT, &vpic) < 0) { perror("VIDIOCGPICT"); close(fd); return (FALSE); }
// if (cap.type & VID_TYPE_MONOCHROME) { // } else { vpic.depth=24; vpic.palette=VIDEO_PALETTE_RGB24;
if(ioctl(fd, VIDIOCSPICT, &vpic) < 0) { printf("Unable to find a supported capture format./n"); return (FALSE); } // }
return (TRUE); }
int closeVideo() { if(fd != -1) { close(fd); return (TRUE); } return (FALSE); }
void getVideoData(unsigned char *data, int size) { size = read(fd, data, size); } /* int main(int argc, char ** argv) { FILE * fp;
BITMAPFILEHEADER bf; BITMAPINFOHEADER bi;
unsigned char * buffer; int i;
fp = fopen(BMP, "wb"); if(!fp){ perror(BMP); exit(1); }
if(openVideo() == FALSE) { return(-1); }
//Set BITMAPINFOHEADER bi.biSize = 40; bi.biWidth = win.width; bi.biHeight = win.height; bi.biPlanes = 1; bi.biBitCount = 24; bi.biCompression = 0; bi.biSizeImage = WIDTHBYTES(bi.biWidth * bi.biBitCount) * bi.biHeight; bi.biXPelsPerMeter = 0; bi.biYPelsPerMeter = 0; bi.biClrUsed = 0; bi.biClrImportant = 0;
//Set BITMAPFILEHEADER bf.bfType = 0x4d42; bf.bfSize = 54 + bi.biSizeImage; bf.bfReserved = 0; bf.bfOffBits = 54;
buffer = malloc(bi.biSizeImage); if (!buffer) { printf("Out of memory./n"); exit(1); }
for(i=0; i<20; i++) getVideoData(buffer, bi.biSizeImage);
fwrite(&bf, 14, 1, fp); fwrite(&bi, 40, 1, fp); fwrite(buffer, bi.biSizeImage, 1, fp);
printf("get bmp form video/t[OK]/n");
fclose(fp); closeVideo(); return 0; } */ |
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