capturebmp.c

EGui是一个开源的图形系统软件,类似于QT/Embedded、GTK-FB、MicroWindow。目标是嵌入式平台整合解 决方案。基于Linux Framebuffer 设备驱动上实现。有完

#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <string.h>

#include <Egui.h>
#include "bmp.h"

EGui_FBinfo Efbinfo;

int
write_file (const char* filename, size_t length,char * buffer)
{
  int fd;

 
  /* Open the file.  */
  fd = open (filename, O_CREAT|O_RDWR|S_IRWXU);
  if (fd < 0)
    {
      printf ("create a new BMP %s file error\n",filename);
      return -1;
    }

  write (fd, buffer, length);

  /* Finish up.  */
  close (fd);
  return 0;
}

int
main(int argc, char **argv)
{
  char * rgbbuf;
  int width,height;
  Ecolor * bgcolor;
  EGui_Window * ewindow;
  
  if (argc <2)
    {
      printf (" A 24 bits BMP capture program for Egui\n");
      printf ("usage : %s filename\n",argv[0]);
      return;
    }


  if (Egui_open (&Efbinfo))
    return ;

  bgcolor = malloc (sizeof ( Ecolor));
  if (bgcolor == NULL)
    {
      printf ("malloc color ERROR\n");
      return -1;
    }

  bgcolor->r = bgcolor->g = bgcolor->b = 0xcc;
  /* create window will initial color's pixel. 
   */
  ewindow = Egui_CreateWindow (&Efbinfo,0,0,Efbinfo.screen_width - 1,
			       Efbinfo.screen_height - 1,bgcolor,EGUI_WINDOW_NORMAL);

  if (ewindow == NULL)
    {
      printf ("New windows failed\n");
      Egui_close ();
      return 1;
    }
  /*do display windows*/
  width  = Efbinfo.screen_width  ;
  height = Efbinfo.screen_height ;

  rgbbuf = (char *) malloc ( width * height * 3);

  if (rgbbuf == NULL)
    {
      printf ("Get a buffer for RGB error!\n");
      return ;
    }

  Egui_getrgb (0,0,width,height,rgbbuf,ewindow);

  save_bmpbuf (width,height,rgbbuf,argv[1]);

  free(rgbbuf);
  Egui_CloseWindow (ewindow);
  free (bgcolor);
  Egui_close ();
}

int 
save_bmpbuf(int width,int height,char * rgbbuf, char * filename)
{
  char *buffer;
  size_t length;
  int i,j;
  char pad_num;
  char *aBitmapBits;
  int tmpwidth;
  int head_size;
  BITMAPFILEHEADER bmfh;
  BITMAPINFOHEADER bmih;
 
  pad_num = width * 3 %4==0? 0 : 4 - width * 3 %4;


  head_size = sizeof (BITMAPFILEHEADER) + sizeof (BITMAPINFOHEADER);

  length = (width * 3 + pad_num ) * height + head_size ;
 /* new head */
  bmfh.bfType      = 0x4D42; 	/* BM */
  bmfh.bfSize      = length;
  bmfh.bfReserved1 = 0;
  bmfh.bfReserved2 = 0;
  bmfh.bfOffBits   = head_size;

  bmih.biSize      = 0x28 	;	/* windows x BMP */
  bmih.biWidth     = width;
  bmih.biHeight    = height;
  bmih.biPlanes    = 1;
  bmih.biBitCount  = 24;         /* 24bits */
  bmih.biCompression = 0; 	/*  */
  bmih.biSizeImage   = (width * 3 + pad_num ) * height;
  //bmih.biXPelsPerMeter = ;
  //  bmih.biYPelsPerMeter;
  bmih.biClrUsed = 0x1000000; 	/* 24bits */

  buffer = (char * )malloc (length);
  if (buffer == NULL)
    {
      printf ("malloc file buffer error\n");
      return -1;
    }

  memcpy (buffer,(void *)&bmfh,sizeof (BITMAPFILEHEADER));
  memcpy (buffer + sizeof (BITMAPFILEHEADER),(void *)&bmih,sizeof (BITMAPINFOHEADER));
  aBitmapBits = (char *)(buffer + head_size);  

  for (j=0,i=height-1; j < height; j ++,i--)
    {
    //line copy
       memcpy(aBitmapBits + i * (width * 3 + pad_num), rgbbuf + j * width * 3,width * 3);	
    }
 
  write_file(filename, length,buffer);

  free(buffer);
  
  return 0;
}