tools/bmp_logo.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3
   4 #if defined(__linux__)
   5 #include <stdint.h>
   6 #else
   7 #ifdef __CYGWIN__
   8 #include "elf.h"
   9 #else
  10 #include <inttypes.h>
  11 #endif
  12 #endif
  13
  14 typedef struct bitmap_s {               /* bitmap description */
  15         uint16_t width;
  16         uint16_t height;
  17         uint8_t palette[256*3];
  18         uint8_t *data;
  19 } bitmap_t;
  20
  21 #define DEFAULT_CMAP_SIZE       16      /* size of default color map    */
  22
  23 /*
  24  * Neutralize little endians.
  25  */
  26 uint16_t le_short(uint16_t x)
  27 {
  28     uint16_t val;
  29     uint8_t *p = (uint8_t *)(&x);
  30
  31     val =  (*p++ & 0xff) << 0;
  32     val |= (*p & 0xff) << 8;
  33
  34     return val;
  35 }
  36
  37 void skip_bytes (FILE *fp, int n)
  38 {
  39         while (n-- > 0)
  40                 fgetc (fp);
  41 }
  42
  43 int main (int argc, char *argv[])
  44 {
  45         int     i, x;
  46         FILE    *fp;
  47         bitmap_t bmp;
  48         bitmap_t *b = &bmp;
  49         uint16_t data_offset, n_colors;
  50
  51         if (argc < 2) {
  52                 fprintf (stderr, "Usage: %s file\n", argv[0]);
  53                 exit (EXIT_FAILURE);
  54         }
  55
  56         if ((fp = fopen (argv[1], "rb")) == NULL) {
  57                 perror (argv[1]);
  58                 exit (EXIT_FAILURE);
  59         }
  60
  61         if (fgetc (fp) != 'B' || fgetc (fp) != 'M') {
  62                 fprintf (stderr, "%s is not a bitmap file.\n", argv[1]);
  63                 exit (EXIT_FAILURE);
  64         }
  65
  66         /*
  67          * read width and height of the image, and the number of colors used;
  68          * ignore the rest
  69          */
  70         skip_bytes (fp, 8);
  71         fread (&data_offset, sizeof (uint16_t), 1, fp);
  72         skip_bytes (fp, 6);
  73         fread (&b->width,   sizeof (uint16_t), 1, fp);
  74         skip_bytes (fp, 2);
  75         fread (&b->height,  sizeof (uint16_t), 1, fp);
  76         skip_bytes (fp, 22);
  77         fread (&n_colors, sizeof (uint16_t), 1, fp);
  78         skip_bytes (fp, 6);
  79
  80         /*
  81          * Repair endianess.
  82          */
  83         data_offset = le_short(data_offset);
  84         b->width = le_short(b->width);
  85         b->height = le_short(b->height);
  86         n_colors = le_short(n_colors);
  87
  88         /* assume we are working with an 8-bit file */
  89         if ((n_colors == 0) || (n_colors > 256 - DEFAULT_CMAP_SIZE)) {
  90                 /* reserve DEFAULT_CMAP_SIZE color map entries for default map */
  91                 n_colors = 256 - DEFAULT_CMAP_SIZE;
  92         }
  93
  94         printf ("/*\n"
  95                 " * Automatically generated by \"tools/bmp_logo\"\n"
  96                 " *\n"
  97                 " * DO NOT EDIT\n"
  98                 " *\n"
  99                 " */\n\n\n"
 100                 "#ifndef __BMP_LOGO_H__\n"
 101                 "#define __BMP_LOGO_H__\n\n"
 102                 "#define BMP_LOGO_WIDTH\t\t%d\n"
 103                 "#define BMP_LOGO_HEIGHT\t\t%d\n"
 104                 "#define BMP_LOGO_COLORS\t\t%d\n"
 105                 "#define BMP_LOGO_OFFSET\t\t%d\n"
 106                 "\n",
 107                 b->width, b->height, n_colors,
 108                 DEFAULT_CMAP_SIZE);
 109
 110         /* allocate memory */
 111         if ((b->data = (uint8_t *)malloc(b->width * b->height)) == NULL) {
 112                 fclose (fp);
 113                 printf ("Error allocating memory for file %s.\n", argv[1]);
 114                 exit (EXIT_FAILURE);
 115         }
 116
 117         /* read and print the palette information */
 118         printf ("unsigned short bmp_logo_palette[] = {\n");
 119
 120         for (i=0; i<n_colors; ++i) {
 121                 b->palette[(int)(i*3+2)] = fgetc(fp);
 122                 b->palette[(int)(i*3+1)] = fgetc(fp);
 123                 b->palette[(int)(i*3+0)] = fgetc(fp);
 124                 x=fgetc(fp);
 125
 126                 printf ("%s0x0%X%X%X,%s",
 127                         ((i%8) == 0) ? "\t" : "  ",
 128                         (b->palette[(int)(i*3+0)] >> 4) & 0x0F,
 129                         (b->palette[(int)(i*3+1)] >> 4) & 0x0F,
 130                         (b->palette[(int)(i*3+2)] >> 4) & 0x0F,
 131                         ((i%8) == 7) ? "\n" : ""
 132                 );
 133         }
 134
 135         /* seek to offset indicated by file header */
 136         fseek(fp, (long)data_offset, SEEK_SET);
 137
 138         /* read the bitmap; leave room for default color map */
 139         printf ("\n");
 140         printf ("};\n");
 141         printf ("\n");
 142         printf ("unsigned char bmp_logo_bitmap[] = {\n");
 143         for (i=(b->height-1)*b->width; i>=0; i-=b->width) {
 144                 for (x = 0; x < b->width; x++) {
 145                         b->data[(uint16_t) i + x] = (uint8_t) fgetc (fp) \
 146                                                 + DEFAULT_CMAP_SIZE;
 147                 }
 148         }
 149         fclose (fp);
 150
 151         for (i=0; i<(b->height*b->width); ++i) {
 152                 if ((i%8) == 0)
 153                         putchar ('\t');
 154                 printf ("0x%02X,%c",
 155                         b->data[i],
 156                         ((i%8) == 7) ? '\n' : ' '
 157                 );
 158         }
 159         printf ("\n"
 160                 "};\n\n"
 161                 "#endif /* __BMP_LOGO_H__ */\n"
 162         );
 163
 164         return (0);
 165 }