读取MP3专辑图片

 #define WIN32_LEAN_AND_MEAN
 #define NOWINRES
 #define NOSERVICE
 #define NOMCX
 #define NOIME
 #include "windows.h"
 
 #include <stdio.h>
 #include <malloc.h>
 
 #define TAG_SIZE(a) (((a)[0]&0x7F)*0x200000 + ((a)[1]&0x7F)*0x4000 + ((a)[2]&0x7F)*0x80 + ((a)[3]&0x7F))
 #define FME_SIZE(a) ((a)[0]*0x1000000 + (a)[1]*0x10000 + (a)[2]*0x100 + (a)[3])
 
 #pragma pack(1)
 
 struct ID3V2Header
 {
     BYTE Header[];
     BYTE Version;
     BYTE reVersion;
     BYTE Flag;
     BYTE Size[];
 };
 
 struct ID3V2Frame
 {
     BYTE FrameID[];
     BYTE Size[];
     BYTE Flag[];
 };
 
 #pragma pack()
 
 BOOL WINAPI ExtractAlbum(const char *inputFile, const char *outputFile)
 {
     FILE *f = fopen(inputFile, "rb");
 
     if (!f)
         return FALSE;
 
     BOOL success = FALSE;
 
     ID3V2Header hdr;
 
     if (fread(&hdr, sizeof(hdr), , f) != )
         goto err;
 
     if (memcmp(hdr.Header, "ID3", ))
         goto err;
 
     while (!feof(f))
     {
         if (ftell(f) - sizeof(hdr) >= TAG_SIZE(hdr.Size))
             break;
 
         ID3V2Frame frame;
 
         if (fread(&frame, sizeof(frame), , f) != )
             break;
 
         if (!memcmp(frame.FrameID, "APIC", ))
         {
             size_t pos = ftell(f);
 
             int ofs = fgetc(f) ?  : ;
 
             while (fgetc(f)) {}
 
             fseek(f, ofs, SEEK_CUR);
 
             size_t len = (pos + FME_SIZE(frame.Size)) - ftell(f);
 
             void *buf = malloc(len);
 
             if (fread(buf, len, , f) == )
             {
                 FILE *fpic = fopen(outputFile, "wb");
 
                 if (fpic)
                 {
                     fwrite(buf, len, , fpic);
                     fclose(fpic);
 
                     success = TRUE;
                 }
             }
 
             free(buf);
 
             continue;
         }
 
         fseek(f, FME_SIZE(frame.Size), SEEK_CUR);
     }
 
 err:
     fclose(f);
 
     return success;
 }