BitmapFuncs.h

   1 #ifndef BITMAPFUNCS_H
   2 #define BITMAPFUNCS_H
   3
   4 #include "Bitmap.h"
   5 #include "ImageData.h"
   6 #include "endianness.h"
   7 #include <stdlib.h>
   8 #include <stdio.h>
   9
  10 static int pad_bmp(ImageData *d) {
  11         unsigned stride = ((((d->width * d->bytesperpixel*8) + 31) & ~31) >> 3);
  12         if(stride == d->width * d->bytesperpixel) return -1;
  13         unsigned x,y;
  14         unsigned outsz = d->height * stride;
  15         unsigned char *out = malloc(outsz), *p = d->data, *q = out;
  16         if(!out) return 0;
  17         for(y = 0; y < d->height; ++y) {
  18                 for(x = 0; x < d->width*d->bytesperpixel; ++x)
  19                         *(q++) = *(p++);
  20                 for(; x < stride; ++x)
  21                         *(q++) = 0;
  22         }
  23         free(d->data);
  24         d->data = out;
  25         d->data_size = outsz;
  26         return 1;
  27 }
  28 static void write_bmp(char *name, ImageData *d) {
  29         FILE *f = fopen(name, "wb");
  30         if(f) {
  31                 struct BITMAPINFOHEADER_X hdr = {
  32                         .bfType = end_htole16(0x4D42),
  33                         .bfSize = end_htole32(sizeof(hdr) + d->data_size),
  34                         .bfOffsetBits = end_htole32(sizeof(hdr)),
  35                         .biSize = end_htole32(sizeof(hdr)-14),
  36                         .biWidth = end_htole32(d->width),
  37                         /* negative height means bmp is stored from top to bottom */
  38                         .biHeight = end_htole32( - d->height),
  39                         .biPlanes = end_htole32(1),
  40                         .biBitCount = end_htole32(d->bytesperpixel * 8),
  41                         .biCompression = 0,
  42                         .biSizeImage = 0,
  43                         .biXPelsPerMeter = end_htole32(0xb11),
  44                         .biYPelsPerMeter = end_htole32(0xb11),
  45                 };
  46                 fwrite(&hdr, 1, sizeof hdr, f);
  47                 pad_bmp(d);
  48                 fwrite(d->data, 1, d->data_size, f);
  49                 fclose(f);
  50         } else {
  51                 fprintf(stderr, "error opening %s\n", name);
  52         }
  53 }
  54
  55 #endif
  56