image-read.zip_像素开始位置

//function definition void ImageRead(AnsiString name,int &width,int &height,int *r,int *g,int *b) { //read image FILE *fp; if((fp=fopen(name.c_str(),"rb"))==NULL) { printf("cannot open bmp.name\n"); return ; } fread(&bfType,sizeof(WORD),1,fp); if(bfType!=0x4d42) {//该值必需是0x4D42，也就是字符'BM' printf("the input map is not bmp type"); return ; } fread(&bfSize,sizeof(DWORD),1,fp); fread(&bfReserved1,sizeof(WORD),1,fp); fread(&bfReserved2,sizeof(WORD),1,fp); fread(&bfOffBits,sizeof(DWORD),1,fp); fread(&bih,sizeof(BITMAPINFOHEADER),1,fp); width=bih.biWidth ; height=bih.biHeight; if(width % 4 !=0) width=width+ (4-width % 4); DWORD size=width*(bih.biBitCount/8)*height; unsigned char* pData=new unsigned char[size]; fread(pData,size,1,fp); int bmWidthBytes=width*bih.biBitCount /8; int bmBitsPixel=bih.biBitCount ; int nBit=bmBitsPixel/8; int z; for (int y=0; y<height; y++) { for (int x=0; x<width; x++) { z=height-y-1; *(r+(y*width+x))=pData[x*nBit+2+z*bmWidthBytes]; *(g+(y*width+x))=pData[x*nBit+1+z*bmWidthBytes]; *(b+(y*width+x))=pData[x*nBit+z*bmWidthBytes]; } } } void ImageWrite(AnsiString name1,int *r,int *g,int *b) { //read image FILE *fw; fw=fopen(name1.c_str(),"wb"); fwrite(&bfType,sizeof(WORD),1,fw); fwrite(&bfSize,sizeof(DWORD),1,fw); fwrite(&bfReserved1,sizeof(WORD),1,fw); fwrite(&bfReserved2,sizeof(WORD),1,fw); fwrite(&bfOffBits,sizeof(DWORD),1,fw); fwrite(&bih,sizeof(BITMAPINFOHEADER),1,fw); int width=bih.biWidth ; int height=bih.biHeight; if(width % 4 !=0) width=width+ (4-width % 4); DWORD size=width*(bih.biBitCount/8)*height; unsigned char* pData=new unsigned char[size]; int bmWidthBytes=width*bih.biBitCount /8; int bmBitsPixel=bih.biBitCount ; int nBit=bmBitsPixel/8; int z; for (int y=0; y<height; y++) { for (int x=0; x<width; x++) { z=height-y-1; pData[x*nBit+2+z*bmWidthBytes]=*(r+(y*width+x)); pData[x*nBit+1+z*bmWidthBytes]=*(g+(y*width+x)); pData[x*nBit+z*bmWidthBytes]=*(b+(y*width+x)); } } fwrite(pData,size,1,fw); }