这种 1 位单色黑白 bmp 图像的二进制表示有什么问题？

如何解决这种 1 位单色黑白 bmp 图像的二进制表示有什么问题？

我编写了一个 ANSI C 代码来构建一个简单的单色 BMP 图像（仅限黑白），每个像素用 1 位表示。

图像像素数为 16*16（32 字节），我选择此大小以避免填充作为可被 4 整除的字节数，然后我用 0xff 填充所有 32 字节以显示白色图像。

这是我的 Ubuntu 终端上的二进制输出

00000000  42 4d 5e 00 00 00 00 00  00 00 3e 00 00 00 28 00  |BM^.......>...(.|
00000010  00 00 10 00 00 00 10 00  00 00 01 00 01 00 00 00  |................|
00000020  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00000030  00 00 00 00 00 00 00 00  00 00 00 00 ff 00 ff ff  |................|
00000040  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|
*
0000005e

我的代码：

#include "stdio.h"
#include "stdint.h"
#include "stdlib.h"

struct bmpHeader{

    unsigned char Signature[2];
    unsigned char FileSize[4];
    unsigned char reserved[4];
    unsigned char  DataOffset[4];
}__attribute__( (packed) );

struct bmpInfoHeader{
    unsigned char Size[4];
    unsigned char Width[4];
    unsigned char Height[4];
    unsigned char Planes[2];
    unsigned char BitsPerPixel[2];
    unsigned char Compression[4];
    unsigned char ImageSize[4];
    unsigned char XpixelsPerM[4];
    unsigned char YpixelsPerM[4];
    unsigned char ColorsUsed[4];
    unsigned char ImportantColors[4];


}__attribute__( (packed) );



int main(void)
{
    uint32_t QR_width = 16; uint32_t QR_height = 16;

    unsigned char palette_data[8] = {0x00,0x00,0xff,0x00};
    uint32_t size = ( ((QR_width*QR_height)/8)+ ( ((QR_width*QR_height) % 8 )? 1 : 0  ) + 54 + sizeof(palette_data));

    struct bmpHeader a;
    struct bmpInfoHeader b;


    unsigned char headerSize = sizeof(a) + sizeof(b) + sizeof(pallete_data);

    printf(" size of struct is %d\n",sizeof(a) + sizeof(b));
    printf(" size of image data in bytes = %d\n",size-54-8);
    printf(" size of file in bytes = %d\n",size);

    a.Signature[0] = 0x42; a.Signature[1] = 0x4d; //'BM'
    a.FileSize[0] = (unsigned char) size;   a.FileSize[1] = (unsigned char) size>>8;    a.FileSize[2] = (unsigned char) size>>16;   a.FileSize[3] = (unsigned char) size>>24;
    a.reserved[0] = 0;  a.reserved[1] = 0;  a.reserved[2] = 0;  a.reserved[3] = 0;
    a.DataOffset[0] = headerSize;   a.DataOffset[1] = headerSize>>8;    a.DataOffset[2] = headerSize>>16;   a.DataOffset[3] = headerSize>>24;
    
    b.Size[0]=40;b.Size[1]=0;b.Size[2]=0;b.Size[3]=0;

    b.Width[0]=QR_width;    b.Width[1]=QR_width >> 8;   b.Width[2]=QR_width >> 16;  b.Width[3]=QR_width >> 24;
    b.Height[0]=QR_height;  b.Height[1]=QR_height>>8;   b.Height[2]=QR_height>>16;  b.Height[3]=QR_height>>24;
    b.Planes[0] = 1; b.Planes[1] = 0;
    b.BitsPerPixel[0] = 1; b.BitsPerPixel[1] = 0;
    b.Compression[0]=0; b.Compression[1]=0; b.Compression[2]=0; b.Compression[3]=0; 
    b.ImageSize[0]=0;   b.ImageSize[1]=0;   b.ImageSize[2]=0;   b.ImageSize[3]=0;   
    
    b.XpixelsPerM[0]=0; b.XpixelsPerM[1]=0; b.XpixelsPerM[2]=0; b.XpixelsPerM[3]=0; 
    b.YpixelsPerM[0]=0; b.YpixelsPerM[1]=0; b.YpixelsPerM[2]=0; b.YpixelsPerM[3]=0; 
    b.ColorsUsed[0]=0;  b.ColorsUsed[1]=0;  b.ColorsUsed[2]=0;  b.ColorsUsed[3]=0;  
    b.ImportantColors[0]=0; b.ImportantColors[1]=0; b.ImportantColors[2]=0; b.ImportantColors[3]=0;

    int i=0;
    char* img = calloc( (QR_width*QR_height)/8,sizeof(unsigned char));
    for(i=0; i<32; i++)
        img[i] = 0xff;


    FILE *fptr = fopen("QRcode.bmp","wb");
    if(fptr != NULL)
    {
        fwrite(&a,sizeof(struct bmpHeader),1,fptr);
        fwrite(&b,sizeof(struct bmpInfoHeader),fptr);
        fwrite(palette_data,sizeof(palette_data),fptr);
        fwrite(img,32,fptr);
        fclose(fptr);
    }   

    free(img);


    return 0;
}

预期结果是一个小的白色 bmp 图像，但我没有正确理解。这里出了什么问题？