C++24位图转换成1位位图源码

以下是C语言实现24位图转换成1位位图的源代码：

#include<stdio.h>
#include<stdlib.h>

#pragma pack(2)
typedef struct tagBITMAPFILEHEADER 
{
    unsigned short    bfType;
    unsigned int      bfSize;
    unsigned short    bfReserved1;
    unsigned short    bfReserved2;
    unsigned int      bfOffBits;
}BITMAPFILEHEADER;

#pragma pack(2)
typedef struct tagBITMAPINFOHEADER 
{
    unsigned int      biSize;
    int               biWidth;
    int               biHeight;
    unsigned short    biPlanes;
    unsigned short    biBitCount;
    unsigned int      biCompression;
    unsigned int      biSizeImage;
    int               biXPelsPerMeter;
    int               biYPelsPerMeter;
    unsigned int      biClrUsed;
    unsigned int      biClrImportant;
}BITMAPINFOHEADER;

typedef struct tagRGBQUAD 
{
    unsigned char    rgbBlue;
    unsigned char    rgbGreen;
    unsigned char    rgbRed;
    unsigned char    rgbReserved;
}RGBQUAD;

typedef struct tagRGBTRIPLE 
{
    unsigned char    rgbtBlue;
    unsigned char    rgbtGreen;
    unsigned char    rgbtRed;
}RGBTRIPLE;

int main(int argc,char *argv[])
{
    if(argc!=3)
    {
        printf("Usage:%s <input_file> <output_file>\n",argv[0]);
        return -1;
    }

    char *input_file=argv[1];
    char *output_file=argv[2];

    FILE *fp_in=fopen(input_file,"rb");
    if(fp_in==NULL)
    {
        printf("Open input file error!\n");
        return -1;
    }

    BITMAPFILEHEADER file_header;
    BITMAPINFOHEADER info_header;
    RGBTRIPLE *p_rgb_buffer=NULL;//24位色图像缓冲区
    unsigned char *p_mono_buffer=NULL;//1位色图像缓冲区

    fread(&file_header,sizeof(BITMAPFILEHEADER),1,fp_in);
    fread(&info_header,sizeof(BITMAPINFOHEADER),1,fp_in);

    //判断位图类型是否为24位色图像
    if(info_header.biBitCount!=24)
    {
        printf("Input file is not a 24-bit color bitmap!\n");
        fclose(fp_in);
        return -1;
    }

    //计算24位色图像每行的字节数
    int row_size=(info_header.biWidth*info_header.biBitCount+31)/32*4;

    //分配24位色图像缓冲区
    p_rgb_buffer=(RGBTRIPLE*)malloc(row_size*info_header.biHeight);
    if(p_rgb_buffer==NULL)
    {
        printf("Allocate memory error!\n");
        fclose(fp_in);
        return -1;
    }

    //读取24位色图像数据
    fseek(fp_in,file_header.bfOffBits,SEEK_SET);
    fread(p_rgb_buffer,row_size*info_header.biHeight,1,fp_in);

    //计算1位色图像每行的字节数
    int mono_row_size=(info_header.biWidth+31)/32*4;

    //分配1位色图像缓冲区
    p_mono_buffer=(unsigned char*)malloc(mono_row_size*info_header.biHeight);
    if(p_mono_buffer==NULL)
    {
        printf("Allocate memory error!\n");
        fclose(fp_in);
        free(p_rgb_buffer);
        return -1;
    }

    //将24位色图像数据转换成1位色图像数据
    for(int i=0;i<info_header.biHeight;i++)
    {
        for(int j=0;j<info_header.biWidth;j++)
        {
            int index=(i*mono_row_size+j/8);
            p_mono_buffer[index]|=((p_rgb_buffer[i*row_size+j].rgbtRed>128)?(1<<(7-j%8)):0);
        }
    }

    //将1位色图像数据写入输出文件
    FILE *fp_out=fopen(output_file,"wb");
    if(fp_out==NULL)
    {
        printf("Open output file error!\n");
        fclose(fp_in);
        free(p_rgb_buffer);
        free(p_mono_buffer);
        return -1;
    }

    fwrite(&file_header,sizeof(BITMAPFILEHEADER),1,fp_out);
    fwrite(&info_header,sizeof(BITMAPINFOHEADER),1,fp_out);
    fwrite(p_mono_buffer,mono_row_size*info_header.biHeight,1,fp_out);

    fclose(fp_in);
    fclose(fp_out);
    free(p_rgb_buffer);
    free(p_mono_buffer);

    return 0;
}

该程序实现了以下功能：

1. 读取24位色位图文件头和信息头信息。
2. 分配24位色图像缓冲区，并读取24位色图像数据。
3. 分配1位色图像缓冲区，将24位色图像数据转换成1位色图像数据。
4. 将1位色图像数据写入输出文件中。
5. 释放分配的内存，关闭文件句柄。