题目：对于一个".bmp"图片，获取其像素值的大小和个数

解析：废话不多说，直接上已经调试好的程序

#define _CRT_SECURE_NO_WARNINGS#include <iostream>using namespace std;#include <windows.h>#include <stdlib.h>#include<math.h>#include <iomanip> #include <fstream>//以下模块是完成BMP图像(彩色图像是24bit RGB各8bit)的像素获取，并存在文件名为xiang_su_zhi.txt中unsigned char *pBmpBuf;//读入图像数据的指针int bmpWidth;//图像的宽int bmpHeight;//图像的高RGBQUAD *pColorTable;//颜色表指针int biBitCount;//图像类型，每像素位数 //读图像的位图数据、宽、高、颜色表及每像素位数等数据进内存，存放在相应的全局变量中bool readBmp(char *bmpName){ FILE *fp = fopen(bmpName, "rb");//二进制读方式打开指定的图像文件 if (fp == 0)  return 0; //跳过位图文件头结构BITMAPFILEHEADER fseek(fp, sizeof(BITMAPFILEHEADER), 0); //定义位图信息头结构变量，读取位图信息头进内存，存放在变量head中 BITMAPINFOHEADER head; fread(&head, sizeof(BITMAPINFOHEADER), 1, fp); //获取图像宽、高、每像素所占位数等信息 bmpWidth = head.biWidth; bmpHeight = head.biHeight; biBitCount = head.biBitCount;//定义变量，计算图像每行像素所占的字节数（必须是4的倍数） int lineByte = (bmpWidth * biBitCount / 8 + 3) / 4 * 4;//灰度图像有颜色表，且颜色表表项为256 if (biBitCount == 8) {  //申请颜色表所需要的空间，读颜色表进内存  pColorTable = new RGBQUAD[256];  fread(pColorTable, sizeof(RGBQUAD), 256, fp); } //申请位图数据所需要的空间，读位图数据进内存 pBmpBuf = new unsigned char[lineByte * bmpHeight]; fread(pBmpBuf, 1, lineByte * bmpHeight, fp); fclose(fp);//关闭文件 return 1;//读取文件成功}//给定一个图像位图数据、宽、高、颜色表指针及每像素所占的位数等信息,将其写到指定文件中bool saveBmp(char *bmpName, unsigned char *imgBuf, int width, int height, int biBitCount, RGBQUAD *pColorTable){ //如果位图数据指针为0，则没有数据传入，函数返回 if (!imgBuf)  return 0; //颜色表大小，以字节为单位，灰度图像颜色表为1024字节，彩色图像颜色表大小为0 int colorTablesize = 0; if (biBitCount == 8)  colorTablesize = 1024; //待存储图像数据每行字节数为4的倍数 int lineByte = (width * biBitCount / 8 + 3) / 4 * 4; //以二进制写的方式打开文件 FILE *fp = fopen(bmpName, "wb"); if (fp == 0)  return 0; //申请位图文件头结构变量，填写文件头信息 BITMAPFILEHEADER fileHead; fileHead.bfType = 0x4D42;//bmp类型   //bfSize是图像文件4个组成部分之和 fileHead.bfSize = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) + colorTablesize + lineByte*height; fileHead.bfReserved1 = 0; fileHead.bfReserved2 = 0; //bfOffBits是图像文件前3个部分所需空间之和 fileHead.bfOffBits = 54 + colorTablesize; //写文件头进文件 fwrite(&fileHead, sizeof(BITMAPFILEHEADER), 1, fp); //申请位图信息头结构变量，填写信息头信息 BITMAPINFOHEADER head; head.biBitCount = biBitCount; head.biClrImportant = 0; head.biClrUsed = 0; head.biCompression = 0; head.biHeight = height; head.biPlanes = 1; head.biSize = 40; head.biSizeImage = lineByte*height; head.biWidth = width; head.biXPelsPerMeter = 0; head.biYPelsPerMeter = 0; //写位图信息头进内存 fwrite(&head, sizeof(BITMAPINFOHEADER), 1, fp); //如果灰度图像，有颜色表，写入文件  if (biBitCount == 8)  fwrite(pColorTable, sizeof(RGBQUAD), 256, fp); //写位图数据进文件 fwrite(imgBuf, height*lineByte, 1, fp); //关闭文件 fclose(fp); return 1;}//以下为像素的读取函数void doIt(){ //读入指定BMP文件进内存，注意要将"nv.BMP"文件和“源.cpp"代码放在同一个文件夹下 char readPath[] = "nv.BMP"; readBmp(readPath); //输出图像的信息 cout << "width=" << bmpWidth << " height=" << bmpHeight << " biBitCount=" << biBitCount << endl; //循环变量，图像的坐标 //每行字节数 int lineByte = (bmpWidth*biBitCount / 8 + 3) / 4 * 4; //循环变量，针对彩色图像，遍历每像素的三个分量 int m = 0, n = 0, count_xiang_su = 0; //将图像左下角1/4部分置成黑色 ofstream outfile("图像像素.txt", ios::in | ios::trunc); if (biBitCount == 8) //对于灰度图像 {  //以下完成图像的分割成8*8小单元，并把像素值存储到指定文本中。由于BMP图像的像素数据是从  //左下角：由左往右，由上往下逐行扫描的  int L1 = 0;  int hang = 63;  int lie = 0;  //int L2=0;  //int fen_ge=8;  for (int fen_ge_hang = 0; fen_ge_hang<8; fen_ge_hang++)//64*64矩阵行循环  {   for (int fen_ge_lie = 0; fen_ge_lie<8; fen_ge_lie++)//64*64列矩阵循环   {    for (L1 = hang; L1>hang - 8; L1--)//8*8矩阵行    {     for (int L2 = lie; L2<lie + 8; L2++)//8*8矩阵列     {      m = *(pBmpBuf + L1*lineByte + L2);      outfile << m << " ";      count_xiang_su++;      if (count_xiang_su % 8 == 0)//每8*8矩阵读入文本文件      {       outfile << endl;      }     }    }        hang = 63 - fen_ge_hang * 8;//64*64矩阵行变换    lie += 8;//64*64矩阵列变换,该一行（64）由8个8*8矩阵的行组成   }   hang -= 8;//64*64矩阵的列变换   lie = 0;//64*64juzhen  } } //double xiang_su[2048]; //ofstream outfile("xiang_su_zhi.txt",ios::in|ios::trunc); if (!outfile) {  cout << "open error!" << endl;  exit(1); } else if (biBitCount == 24) {   //彩色图像  for (int i = 0; i<bmpHeight; i++)  {   for (int j = 0; j<bmpWidth; j++)   {    for (int k = 0; k<3; k++)//每像素RGB三个分量分别置0才变成黑色    {     //*(pBmpBuf+i*lineByte+j*3+k)-=40;     m = *(pBmpBuf + i*lineByte + j * 3 + k);     outfile << m << " ";     count_xiang_su++;     if (count_xiang_su % 8 == 0)     {      outfile << endl;     }         }    n++;   }  }  cout << "总的像素个素为(即大小):" << n << endl;   } //将图像数据存盘 char writePath[] = "nvcpy.BMP";//图片处理后再存储 saveBmp(writePath, pBmpBuf, bmpWidth, bmpHeight, biBitCount, pColorTable); //清除缓冲区，pBmpBuf和pColorTable是全局变量，在文件读入时申请的空间 delete[]pBmpBuf; if (biBitCount == 8)  delete[]pColorTable;}void main(){ doIt(); system("pause");}