C语言将二进制浮点显示到BMP格式文件（float2bmp.c）

#include <stdio.h>#include <stdlib.h>#include <string.h>#include <math.h>#define BM 19778                    // The ASCII code for BM#define sizeofFILE 14#define sizeofINFO 40float v[2000][2000];typedef struct _tagBMP_FILEHEADER{ unsigned short bfType;        //2Bytes，必须为"BM"，即0x424D 才是Windows位图文件unsigned int   bfSize;         //4Bytes，整个BMP文件的大小unsigned short bfReserved1;  //2Bytes，保留，为0unsigned short bfReserved2;  //2Bytes，保留，为0unsigned int   bfOffBits;     //4Bytes，文件起始位置到图像像素数据的字节偏移量} BMP_FILEHEADER;typedef struct _tagBMP_INFOHEADER{unsigned int     biSize;    //4Bytes，INFOHEADER结构体大小，存在其他版本I NFOHEADER，用作区分unsigned int     biWidth;    //4Bytes，图像宽度（以像素为单位）unsigned int     biHeight;    //4Bytes，图像高度，+：图像存储顺序为Bottom2Top，-：Top2Bottomunsigned short   biPlanes;    //2Bytes，图像数据平面，BMP存储RGB数据，因此总为1unsigned short   biBitCount;         //2Bytes，图像像素位数unsigned int     biCompression;     //4Bytes，0：不压缩，1：RLE8，2：RLE4unsigned int     biSizeImage;       //4Bytes，4字节对齐的图像数据大小unsigned int     biXPelsPerMeter;   //4 Bytes，用象素/米表示的水平分辨率unsigned int     biYPelsPerMeter;   //4 Bytes，用象素/米表示的垂直分辨率unsigned int     biClrUsed;          //4 Bytes，实际使用的调色板索引数，0：使用所有的调色板索引unsigned int     biClrImportant;     //4 Bytes，重要的调色板索引数，0：所有的调色板索引都重要}BMP_INFOHEADER;void write_file(FILE *fp,BMP_FILEHEADER *fileheader){   fseek(fp, 0L, SEEK_SET);   fwrite(&fileheader->bfType, 2L, 1, fp);   fwrite(&fileheader->bfSize, 4L, 1, fp);   fwrite(&fileheader->bfReserved1, 2L, 1, fp);   fwrite(&fileheader->bfReserved2, 2L, 1, fp);   fwrite(&fileheader->bfOffBits, 4L, 1, fp);   fseek(fp, 0L, SEEK_SET);}void write_info(FILE *fp, BMP_INFOHEADER *infoheader){   fseek(fp, sizeofFILE, SEEK_SET);   fwrite(&infoheader->biSize, 4L, 1, fp);   fwrite(&infoheader->biWidth, 4L, 1, fp);   fwrite(&infoheader->biHeight, 4L, 1, fp);   fwrite(&infoheader->biPlanes, 2L, 1, fp);   fwrite(&infoheader->biBitCount, 2L, 1, fp);   fwrite(&infoheader->biCompression, 4L, 1, fp);   fwrite(&infoheader->biSizeImage, 4L, 1, fp);   fwrite(&infoheader->biXPelsPerMeter, 4L, 1, fp);   fwrite(&infoheader->biYPelsPerMeter, 4L, 1, fp);   fwrite(&infoheader->biClrUsed, 4L, 1, fp);   fwrite(&infoheader->biClrImportant, 4L, 1, fp);}void main(int argc, char* argv[]){   int stride,i,j,width,height,nx,nz;   unsigned char* pixout=NULL;   BMP_FILEHEADER fileheader;   BMP_INFOHEADER infoheader;   width=600;    nx=600;   height=300;   nz=300;   FILE *fp,*fpout;   if((fp=fopen("migration.dat","rb"))==NULL){printf("Open file error! \n");exit(0);}   for(i=0;i<nx;i++)      for(j=0;j<nz;j++)          fread(&v[i][j],sizeof(float),1,fp);   fpout=fopen("out.bmp","wb");   fileheader.bfType=19778;   fileheader.bfSize=54+3*width*height;   fileheader.bfReserved1=0;   fileheader.bfReserved2=0;   fileheader.bfOffBits=54;   if (BM != fileheader.bfType){printf("This file is not bmp file.!!!\n");exit(1);}   printf("\nThe BMP picture file header as following:\n");   printf("--Type=%u,\n",fileheader.bfType);   printf("--Size=%d,\n",fileheader.bfSize);   printf("--Reserved1=%u,\n",fileheader.bfReserved1);   printf("--Reserved2=%u,\n",fileheader.bfReserved2);   printf("--bfOffBits=%d,\n",fileheader.bfOffBits);   write_file(fpout,&fileheader);   infoheader.biSize=40;   infoheader.biWidth=width;   infoheader.biHeight=height;   infoheader.biPlanes=1;   infoheader.biBitCount=24;   infoheader.biCompression=0;   infoheader.biSizeImage=3*width*height;   infoheader.biXPelsPerMeter=0;   infoheader.biYPelsPerMeter=0;   infoheader.biClrUsed=0;   infoheader.biClrImportant=0;   printf("\nThe BMP picture information header as following:\n");   printf("--size=%d,\n",infoheader.biSize);   printf("--width=%d,\n",infoheader.biWidth);   printf("--height=%d,\n",infoheader.biHeight);   printf("--planes=%u,\n",infoheader.biPlanes);   printf("--bitcount=%u,\n",infoheader.biBitCount);   printf("--Compression=%d,\n",infoheader.biCompression);   printf("--SizeImage=%d,\n",infoheader.biSizeImage);   printf("--XPelsPerMeter=%d,\n",infoheader.biXPelsPerMeter);   printf("--YPelsPerMeter=%d,\n",infoheader.biYPelsPerMeter);   printf("--ClrUsed=%d,\n",infoheader.biClrUsed);   printf("--ClrImportant=%d,\n",infoheader.biClrImportant);   write_info(fpout,&infoheader);   stride=(24*width+31)/8;   stride=stride/4*4;   pixout=malloc(stride);    fseek(fpout, fileheader.bfOffBits, SEEK_SET);   for( j=0 ; j<height ; j++ )   {      for( i=0 ; i<width ; i++ )       {          pixout[i*3+2]=(unsigned char)v[(int)(i*1.0*nx/width)][(int)((height-1-j)*1.0*nz/height)];          pixout[i*3+1]=(unsigned char)v[(int)(i*1.0*nx/width)][(int)((height-1-j)*1.0*nz/height)];          pixout[i*3]  =(unsigned char)v[(int)(i*1.0*nx/width)][(int)((height-1-j)*1.0*nz/height)];       }      fwrite(pixout, 1, stride, fpout);   }   fclose(fp);}