C++中依像素读取BMP文件并显示，显示的有关问题

C++中依像素读取BMP文件并显示，显示的问题
在此先行谢谢帮助我的大侠了！
我在C++中用自定义的BITMAPFILEHEADER和BITMAPINFOHEADER读取BMP，然后用SetPixel()显示出来。为了清楚地解释我遇到的问题，请看下面的图：

这是256*256的lena.bmp。左边是原图，右边是我程序的输出。请您看最左边有一个长条矩形，本来这一条应该是图的最右侧才对。

还有另外一个问题，请看：

这个图是146*146的bmp，是我随便截屏来的。下面这幅图是程序输出，不仅仍是最右侧的一条跑到最左侧来了，而且颜色也变得很奇怪。这如果是程序的问题的话，为什么lena里没有出现呢？如果是图片本身的问题，那么应该是什么问题呢？
我的代码如下，可以直接跑的：

C/C++ code


/*****BMP.h*****/
#include <fstream>
#include <Windows.h>
#define N 384
using namespace std;

typedef struct {
   WORD bfType;                 /* Magic identifier            */
   DWORD bfSize;                       /* File size in bytes          */
   WORD bfReserved1;
   WORD bfReserved2;
   DWORD bfOffBits;                     /* Offset to image data, bytes */
} HEADER;

typedef struct {
   DWORD biSize;               /* Header size in bytes      */
   LONG biWidth;                /* Width and height of image */
   LONG biHeight;
   WORD biPlanes;       /* Number of colour planes   */
   WORD biBitCount;         /* Bits per pixel            */
   DWORD biCompression;        /* Compression type          */
   DWORD biSizeImage;          /* Image size in bytes       */
   LONG biXPelsPerMeter;     /* Pixels per meter          */
   LONG biYPelsPerMeter;
   DWORD biClrUsed;           /* Number of colours         */
   DWORD biClrImportant;   /* Important colours         */
} INFOHEADER;

C/C++ code


#include "BMP.h"

HEADER bmfh;        //bitmap file header
INFOHEADER bmih;    //bitmap info header
BYTE R[N][N], G[N][N], B[N][N];                        //RGB value of every pixel
COLORREF color[N][N];    //color
extern "C" WINBASEAPI HWND WINAPI GetConsoleWindow ();    //initialize the screen
void ReadBmp(char *BmpFileName);
void GetColor(int i, int j);

void main()
{
    HWND hwnd;    //handlers HWND and HDC
    HDC hdc;
    char BmpFileName[10];
    int i, j;
    
    hwnd = GetConsoleWindow();    //initialize the screen
    hdc = GetDC(hwnd);  
    scanf("%s", BmpFileName);
    ReadBmp(BmpFileName);    //read the BMP file
    for(i = 0; i < bmih.biHeight; i++)
        for(j = 0; j < bmih.biWidth; j++)
            SetPixel(hdc, i, j, color[bmih.biWidth - j][i]);    //draw the BMP image
    ReleaseDC(hwnd,hdc);
}

void ReadBmp(char *BmpFileName)        //read the BMP file
{
    int patch;    //number of 0s for complement in every row
    ifstream in(BmpFileName, ios_base::binary);        //open the BMP file
    in.read((char *)(&bmfh), sizeof(bmfh) - 2);        //read in BITMAPFILEHEADER. Here sizeof returns a value larger than struct size, so "-2"
    if(bmfh.bfType != 0x4d42)                        //if not BMP, exit
    {
        printf("File type is not BMP!\n");
        exit(1);
    }
    in.read((char *)(&bmih),sizeof(bmih));        //read in BITMAPINFOHEADER
    in.seekg(bmfh.bfOffBits, ios_base::beg);    //seek bitmap data
    patch = (4 - (bmih.biWidth * 3) % 4) % 4;    //calculate number of 0s for complement in every row
    for(int i = 0; i < abs(bmih.biHeight); i++)    
    {
        for(int j = 0; j < abs(bmih.biWidth); j++)
        {
            in.read((char *)(&R[i][j]), 1);        //read in data pixel by pixel
            in.read((char *)(&G[i][j]), 1);
            in.read((char *)(&B[i][j]), 1);
            GetColor(i, j);        //obtain the original and greyscaled color
        }
        in.seekg(patch, ios_base::cur);    //skip 0s for complement in every row
    }
}

void GetColor(int i, int j)        //obtain the original and greyscaled color
{
    int iB, iG, iR;
    iB = (int)(B[i][j]);
    iG = (int)(G[i][j]);
    iR = (int)(R[i][j]);
    color[i][j] = RGB(iB, iG, iR);    //original color
}

C++中依像素读取BMP文件并显示，显示的有关问题

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