[C] 讀取和寫出一個24bit的bmp圖片

#include <iostream>
#include <fstream>
#include <windows.h>

typedef unsigned char   BYTE;
typedef unsigned short  WORD;
typedef unsigned long   DWORD;
typedef long            LONG;

//#define MAXPIX 512

using namespace std;


struct RGBDATA{
        BYTE rgbtRed;  
		BYTE rgbtGreen;
		BYTE rgbtBlue;
    };

void main(){

   BITMAPFILEHEADER	FileHeader;
	 BITMAPINFOHEADER	InfoHeader;
	 RGBTRIPLE color[345][300];
	 int ImageX, ImageY;

	 BYTE   ByteBuf;
	 int fix;
	 int i, j, n;
	 FILE *fp;
	 FILE *out;
	 char filename[20];

  /* 開啟檔案 */
  scanf("%s", filename);
  fp = fopen(filename, "rb");
  out = fopen("out.bmp", "wb");

  /* 先讀取檔頭資訊 */
  fread(&FileHeader, sizeof(BITMAPFILEHEADER), 1, fp);
  fread(&InfoHeader, sizeof(BITMAPINFOHEADER), 1, fp);

  fwrite (&FileHeader , 1 , sizeof(BITMAPFILEHEADER) , out );
  fwrite (&InfoHeader , 1 , sizeof(BITMAPINFOHEADER) , out );

  /* 確定格式 */
  if( FileHeader.bfType != 'MB' )
     return;
  if( InfoHeader.biCompression != 0 )
     return;
  if( InfoHeader.biBitCount != 24 )
     return;

  /* 取得圖寬及圖高 */
  ImageX = InfoHeader.biWidth;
  ImageY = InfoHeader.biHeight;

  printf("ImageX:%d\n",ImageX);
  printf("ImageY:%d\n",ImageY);

  /* 計算每列需略過的 bytes 數 */
  if( (ImageX*3)%4 != 0)
     fix = 4 - ((ImageX*3)%4);
  else
     fix = 0;

  /* 圖入各像素資訊 */
  RGBDATA rgb;

  for( i=ImageY-1; i>=0; i-- )
  {
     for( j=0; j<ImageX; j++ )
     {
		  
          fread(&rgb, sizeof(RGBTRIPLE), 1, fp);
          color[j][i].rgbtBlue = rgb.rgbtBlue;
          color[j][i].rgbtGreen = rgb.rgbtGreen;
          color[j][i].rgbtRed = rgb.rgbtRed;
     }
     /* 略過各列多餘的資訊 */
	 for( n=0; n<fix; n++ ){
          fread(&ByteBuf, sizeof(BYTE), 1, fp);
		  //fwrite(&ByteBuf , 1 , sizeof(ByteBuf) , out);
	 }
  }

  for( i=ImageY-1; i>=0; i-- )
  {
     for( j=ImageX-1; j>= 0 ; j-- )
     {
		  
          rgb.rgbtBlue = color[j][i].rgbtBlue;
          rgb.rgbtGreen = color[j][i].rgbtGreen;
          rgb.rgbtRed = color[j][i].rgbtRed;
		  fwrite (&rgb , 1 , sizeof(RGBTRIPLE) , out);
     }
     /* 略過各列多餘的資訊 */
	 for( n=0; n<fix; n++ ){
 		  fwrite(&ByteBuf , 1 , sizeof(ByteBuf) , out);
	 }
  }
	fclose(fp);
	fclose(out);

	system("pause");
}