v4l_lin.c

这是一个通过video4linux的支持

/******************************林启俊_V4L_采集************************************************
****                                      *
***作者: 林启俊                         *      *
***日期:  2006-11-30                 *             *
***                               *                   *
***                             *  ALL RIGHTS Reserved  *
***   
***版本: 1.0                        *                 *
***环境: Linux                         *         *
***                                         *
***目的: 为3G手机的现场直播而准备    
***申明: 一切解释权本人作解释;不得修改(除非经本人同意),不得发表!
***
*** e_mail:   [e-mail]
*******************************************************************************************
***人生格言:   为人生理想而战斗,不怕辛苦!! 为报答父母而奋斗,不怕劳累!!                     ********************

********************************************************************************************
**说明: 此程序尽力让V4L简单而写,采用调用函数来实现;希望对学习V4L的朋友有所帮助                         **********
**     我的摄像头只支持两贞采集,我的想法是,每采集一贞就保存了一个图像;所以我设了两个图像文件           *********
****      /home/linzi.jpeg和/home/linzicheng.jpeg;用的时候可以随便保存到任何地方的                  *******************
***
***   Please email to me if you have some problems or advices to me to modify! than you !!                    ***********/
 

#include "v4l_linqijun.h"


 int  lin_get_open(char *p)
 
  {   
    if( (fd=open(p,O_RDWR,0666))<0)
          return -1;
      else 
          return 0;
 }

   

int   lin_get_capability(int fd, cap* capability)
  
  {  if ( ioctl(fd ,VIDIOCGCAP, capability)<0)
  
          return -1;
   else  
             return 0;
}

int  lin_get_picture(int fd, pic* pic)
{ 
    if(ioctl(fd,VIDIOCGPICT,pic)<0)
        return -1;
    else 
        return 0;

}

int lin_set_picture(int fd,pic* pic)
  
 { 
      pic->colour=50000;                   //没有颜色,黑白的;
      pic->hue=0;                     //灰度为0;
    //  pic->whiteness=65535;
      // pic->contrast=2000;
   if(ioctl(fd,VIDIOCSPICT,pic)<0)
          return -1;
  else 
       return 0;
}


int lin_set_window(int fd, win* win)

{        win->x =0;
        win->y =0 ;
        win->width = 320;
        win->height =240;
      
        
    if(ioctl(fd,VIDIOCSWIN, win)==-1)
         
          return -1;
   
   else
            return 0;
}

int lin_get_mbuf(int fd,mb *mbuf)
{
     
    if(ioctl(fd,VIDIOCGMBUF,mbuf)<0)
      return -1;
    else  
        return 0;
}
    
int lin_set_mmap(mm* mmap)
 
{     mmap->width=window.width;
      mmap->height=window.height;
      mmap->format =picture.palette; 

      mmap->frame=0;
      return 0;
}
      

int lin_memory_map(int fd,int size)

 { 
     map=mmap(NULL,size,PROT_READ|PROT_WRITE,MAP_SHARED,fd,0);
    if(map==MAP_FAILED)
         return -1;
    else  
         
             { printf("map address is %p\n",map);
                return 0; 
             }
}
int lin_start_capture(int fd, mm* mmap)

{     int j=0;
      int frame=0;

  if(ioctl(fd,VIDIOCMCAPTURE,mmap)<0)                     //这一定要是mmap,它就是地址了;呵呵
       {  
         perror("\t\n DIOCMCAPTURE\n");
          return -1;
         }
else  
        printf("\t\nCAPTURE SUCCESS \n");
 



 while(j<mbuf.frames)
  { 
    if (ioctl(fd, VIDIOCSYNC, &frame) < 0) 
         
           
       {  perror("\t v4l_grab_sync\n"); return -1;}
      
    else 
         printf(" \t SYNC  success!\n");

      frame=(frame+1)%2;
     
      mmap->frame=frame;

    if(ioctl(fd,VIDIOCMCAPTURE,mmap)<0)
       
        {perror(" \t\nVIDIOCMCAPTURE\n"); return -1;}
       
    else 
       printf("\t\n next frame capture sucess\n");
    
j++;

}

return 0;

}
     
char* lin_get_mapaddress(int frame)

 {    
     char *frameaddress="";
     frameaddress=map+mbuf.offsets[frame];
     if(frameaddress>0)
     {
      printf("frameadress is %p\n",frameaddress);
      return  frameaddress;
     }
   else 
       return NULL;
}