rh9实现linux视频捕获

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___

 

/****************************************************/

/*                                                  */

/*                      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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