static stbi_uc *stbi__readval(stbi__context *s, int channel, stbi_uc *dest)
{
   int mask=0x80, i;

   for (i=0; i<4; ++i, mask>>=1) {
      if (channel & mask) {
         if (stbi__at_eof(s)) return stbi__errpuc("bad file","PIC file too short");
         dest[i]=stbi__get8(s);
      }
   }

   return dest;
}
Unknown