| 1 | /* |
| 2 | // source code for the BMGLib Utility functions |
| 3 | // |
| 4 | // Copyright (C) 2001 M. Scott Heiman |
| 5 | // All Rights Reserved |
| 6 | // |
| 7 | // You may use the software for any purpose you see fit. You may modify |
| 8 | // it, incorporate it in a commercial application, use it for school, |
| 9 | // even turn it in as homework. You must keep the Copyright in the |
| 10 | // header and source files. This software is not in the "Public Domain". |
| 11 | // You may use this software at your own risk. I have made a reasonable |
| 12 | // effort to verify that this software works in the manner I expect it to; |
| 13 | // however,... |
| 14 | // |
| 15 | // THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS" AND |
| 16 | // WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE, INCLUDING |
| 17 | // WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A |
| 18 | // PARTICULAR PURPOSE. IN NO EVENT SHALL MICHAEL S. HEIMAN BE LIABLE TO |
| 19 | // YOU OR ANYONE ELSE FOR ANY DIRECT, SPECIAL, INCIDENTAL, INDIRECT OR |
| 20 | // CONSEQUENTIAL DAMAGES OF ANY KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING |
| 21 | // WITHOUT LIMITATION, LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, |
| 22 | // OR THE CLAIMS OF THIRD PARTIES, WHETHER OR NOT MICHAEL S. HEIMAN HAS |
| 23 | // BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON |
| 24 | // ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE |
| 25 | // POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE. |
| 26 | */ |
| 27 | |
| 28 | #include <stdlib.h> |
| 29 | #include "BMGUtils.h" |
| 30 | |
| 31 | #ifndef _WIN32 |
| 32 | #include <string.h> |
| 33 | #endif // _WIN32 |
| 34 | |
| 35 | /* error strings for all BMG errors */ |
| 36 | static char BMGErrorStrings[17][128] = { |
| 37 | "No Error", |
| 38 | "Corrupted file or invalid file format", |
| 39 | "Invalid bits per pixel for this file format", |
| 40 | "Memory allocation error", |
| 41 | "Invalid requested image size", |
| 42 | "Invalid bitmap handle", |
| 43 | "Windows API Error", /* this will be overwritten */ |
| 44 | "Unable to open file", |
| 45 | "Unsupported file format option", |
| 46 | "Invalid pointer to a BMG image", |
| 47 | "Unsupported file extension", |
| 48 | "Error reading file", |
| 49 | "Error writing to the output file", |
| 50 | "Invalid pointer to a GeoTIFF structure", |
| 51 | "The background image is undefined", |
| 52 | "The background image is too small", |
| 53 | "Corrupt File" |
| 54 | }; |
| 55 | |
| 56 | /* stores last BMG error */ |
| 57 | static BMGError LastBMGError; |
| 58 | |
| 59 | /* sets the last BMG error */ |
| 60 | void SetLastBMGError( BMGError err ) |
| 61 | { |
| 62 | LastBMGError = err; |
| 63 | } |
| 64 | |
| 65 | /* returns the last error state */ |
| 66 | BMGError GetLastBMGError(void) |
| 67 | { |
| 68 | return LastBMGError; |
| 69 | } |
| 70 | /* gets the error message */ |
| 71 | void GetLastBMGErrorMessage( const char **msg ) |
| 72 | { |
| 73 | if ( LastBMGError == errWindowsAPI ) |
| 74 | { |
| 75 | char* lpMsgBuf = "Erreur BMG\n"; |
| 76 | |
| 77 | /* copy the string. */ |
| 78 | strcpy( BMGErrorStrings[(int)LastBMGError], (char *)lpMsgBuf ); |
| 79 | } |
| 80 | |
| 81 | *msg = BMGErrorStrings[(int)LastBMGError]; |
| 82 | } |
| 83 | |
| 84 | /* Global background color variables */ |
| 85 | static unsigned char BackgroundColor[4]; |
| 86 | static struct BMGImageStruct BackgroundImage; |
| 87 | |
| 88 | /* this function simply initializes the background info. It is called from |
| 89 | the DllEntryPoint function */ |
| 90 | void InitBackground(void) |
| 91 | { |
| 92 | memset( (void *)BackgroundColor, 0xFF, 3 ); /* white */ |
| 93 | BackgroundColor[3] = 0; /* ignored */ |
| 94 | InitBMGImage( &BackgroundImage ); |
| 95 | } |
| 96 | |
| 97 | unsigned char *GetBackgroundColor(void) |
| 98 | { |
| 99 | return &BackgroundColor[0]; |
| 100 | } |
| 101 | |
| 102 | struct BMGImageStruct *GetBackgroundImage(void) |
| 103 | { |
| 104 | return &BackgroundImage; |
| 105 | } |
| 106 | |
| 107 | /* converts an array of 1-bit scanlines to 8-bit scanlines */ |
| 108 | void Convert1to8( struct BMGImageStruct img, |
| 109 | unsigned char *out ) |
| 110 | { |
| 111 | unsigned char *p, *q, *r, *s, *end; |
| 112 | int i; |
| 113 | |
| 114 | q = out; |
| 115 | |
| 116 | for ( s = img.bits; s < img.bits + img.scan_width * img.height; |
| 117 | s += img.scan_width, q += img.width ) |
| 118 | { |
| 119 | i = img.width % 8; |
| 120 | end = q + img.width - i; |
| 121 | p = s; |
| 122 | for ( r = q; r < end; p++ ) |
| 123 | { |
| 124 | *r++ = (unsigned char)((*p & 0x80) ? 1 : 0); |
| 125 | *r++ = (unsigned char)((*p & 0x40) ? 1 : 0); |
| 126 | *r++ = (unsigned char)((*p & 0x20) ? 1 : 0); |
| 127 | *r++ = (unsigned char)((*p & 0x10) ? 1 : 0); |
| 128 | *r++ = (unsigned char)((*p & 0x08) ? 1 : 0); |
| 129 | *r++ = (unsigned char)((*p & 0x04) ? 1 : 0); |
| 130 | *r++ = (unsigned char)((*p & 0x02) ? 1 : 0); |
| 131 | *r++ = (unsigned char)(*p & 0x01); |
| 132 | } |
| 133 | |
| 134 | if ( i-- ) |
| 135 | { |
| 136 | *r++ = (unsigned char)((*p & 0x80) ? 1 : 0); |
| 137 | if ( i-- ) |
| 138 | { |
| 139 | *r++ = (unsigned char)((*p & 0x40) ? 1 : 0); |
| 140 | if ( i-- ) |
| 141 | { |
| 142 | *r++ = (unsigned char)((*p & 0x20) ? 1 : 0); |
| 143 | if ( i-- ) |
| 144 | { |
| 145 | *r++ = (unsigned char)((*p & 0x10) ? 1 : 0); |
| 146 | if ( i-- ) |
| 147 | { |
| 148 | *r++ = (unsigned char)((*p & 0x08) ? 1 : 0); |
| 149 | if ( i-- ) |
| 150 | { |
| 151 | *r++ = (unsigned char)((*p & 0x04) ? 1 : 0); |
| 152 | if ( i ) |
| 153 | *r = (unsigned char)((*p & 0x02) ? 1:0); |
| 154 | } |
| 155 | } |
| 156 | } |
| 157 | } |
| 158 | } |
| 159 | } |
| 160 | } |
| 161 | } |
| 162 | |
| 163 | /* converts an array of 4-bit scanlines to 8-bit scanlines */ |
| 164 | void Convert4to8( struct BMGImageStruct img, |
| 165 | unsigned char *out ) |
| 166 | { |
| 167 | unsigned char *p, *q, *r, *s, *end; |
| 168 | int i; |
| 169 | |
| 170 | q = out; |
| 171 | |
| 172 | for ( s = img.bits; s < img.bits + img.scan_width * img.height; |
| 173 | s += img.scan_width, q += img.width ) |
| 174 | { |
| 175 | i = img.width % 2; |
| 176 | end = q + img.width - i; |
| 177 | p = s; |
| 178 | for ( r = q; r < end; p++ ) |
| 179 | { |
| 180 | *r++ = (unsigned char)((*p >> 4) & 0x0F); |
| 181 | *r++ = (unsigned char)(*p & 0x0F); |
| 182 | } |
| 183 | |
| 184 | if ( i ) |
| 185 | *r = (unsigned char)((*p >> 4) & 0x0F); |
| 186 | } |
| 187 | } |
| 188 | |
| 189 | /****************************************************************************/ |
| 190 | /* this function performs alpha blending. It is a variation of a function |
| 191 | that I found in the PNG example code */ |
| 192 | unsigned char AlphaComp( unsigned char fg, |
| 193 | unsigned char alpha, |
| 194 | unsigned char bg ) |
| 195 | { |
| 196 | unsigned char out; |
| 197 | unsigned short temp; |
| 198 | |
| 199 | switch ( alpha ) |
| 200 | { |
| 201 | case 0: |
| 202 | out = bg; |
| 203 | break; |
| 204 | case 255: |
| 205 | out = fg; |
| 206 | break; |
| 207 | default: |
| 208 | temp = ((unsigned short)(fg)*(unsigned short)(alpha) + |
| 209 | (unsigned short)(bg)*(unsigned short)(255 - |
| 210 | (unsigned short)(alpha)) + (unsigned short)128); |
| 211 | out = (unsigned char)((temp + (temp >> 8)) >> 8); |
| 212 | break; |
| 213 | } |
| 214 | return out; |
| 215 | } |
| 216 | |
| 217 | /**************************************************************************** |
| 218 | // Converts a 16 BPP image to a 24 BPP image |
| 219 | // returns 1 if successfull, 0 otherwise */ |
| 220 | BMGError Convert16to24( struct BMGImageStruct *img ) |
| 221 | { |
| 222 | unsigned int i; |
| 223 | unsigned int new_scan_width; |
| 224 | unsigned char *new_bits; |
| 225 | |
| 226 | /* this function will only work with 16 BBP images */ |
| 227 | if ( img->bits_per_pixel != 16 ) |
| 228 | return errInvalidPixelFormat; |
| 229 | |
| 230 | /* calculate the new scan width */ |
| 231 | new_scan_width = 3 * img->width; |
| 232 | if ( new_scan_width % 4 && img->opt_for_bmp ) |
| 233 | new_scan_width += 4 - new_scan_width % 4; |
| 234 | |
| 235 | /* allocate memory for the new pixel values */ |
| 236 | new_bits = (unsigned char *)calloc( new_scan_width * img->height, sizeof(unsigned char) ); |
| 237 | if ( new_bits == NULL ) |
| 238 | return errMemoryAllocation; |
| 239 | |
| 240 | /* convert the 16 BPP pixel values to the equivalent 24 BPP values */ |
| 241 | for ( i = 0; i < img->height; i++ ) |
| 242 | { |
| 243 | unsigned char *p24; |
| 244 | unsigned short *p16 = (unsigned short *)(img->bits + i * img->scan_width); |
| 245 | unsigned char *start = new_bits + i * new_scan_width; |
| 246 | unsigned char *end = start + new_scan_width; |
| 247 | for ( p24 = start; p24 < end; p24 += 3, p16++ ) |
| 248 | { |
| 249 | p24[0] = (unsigned char)( (*p16 & 0x001F) << 3 ); |
| 250 | p24[1] = (unsigned char)( (*p16 & 0x03E0) >> 2 ); |
| 251 | p24[2] = (unsigned char)( (*p16 & 0x7C00) >> 7 ); |
| 252 | } |
| 253 | } |
| 254 | |
| 255 | free( img->bits ); |
| 256 | img->bits = new_bits; |
| 257 | img->scan_width = new_scan_width; |
| 258 | img->bits_per_pixel = 24; |
| 259 | |
| 260 | return BMG_OK; |
| 261 | } |
| 262 | |
| 263 | /****************************************************************************/ |
| 264 | /* this function undoes alpha blending - kind-a-sort-of ;-) */ |
| 265 | unsigned char InverseAlphaComp( unsigned char fg, unsigned char alpha, |
| 266 | unsigned char bg ) |
| 267 | { |
| 268 | unsigned char out; |
| 269 | short temp; |
| 270 | |
| 271 | switch ( alpha ) |
| 272 | { |
| 273 | case 0: |
| 274 | out = bg; |
| 275 | break; |
| 276 | case 255: |
| 277 | out = fg; |
| 278 | break; |
| 279 | default: |
| 280 | temp = (255*fg - bg*(255-alpha))/alpha; |
| 281 | if ( temp < 0 ) |
| 282 | temp = 0; |
| 283 | out = (unsigned char)temp; |
| 284 | break; |
| 285 | } |
| 286 | return out; |
| 287 | } |
| 288 | |
| 289 | /****************************************************************************/ |
| 290 | /* |
| 291 | // Creates a BITMAPINFOHEADER for the given width, height, bit count, and |
| 292 | // compression. Compression must = BI_RGB, BI_BITFIELDS, BI_RLE4, or BI_RLE8. |
| 293 | */ |
| 294 | BITMAPINFO InternalCreateBMI( unsigned int dwWidth, /* width */ |
| 295 | unsigned int dwHeight, /* height */ |
| 296 | unsigned short wBitCount, /* bit count */ |
| 297 | int compression ) /* compression type */ |
| 298 | { |
| 299 | BITMAPINFO bi; /* bitmap header */ |
| 300 | unsigned int dwBytesPerLine; /* Number of bytes per scanline */ |
| 301 | |
| 302 | /* clear the bitmapinfo structure */ |
| 303 | memset(&bi, 0, sizeof(BITMAPINFO)); |
| 304 | |
| 305 | /* Make sure bits per pixel is valid */ |
| 306 | if (wBitCount <= 1) |
| 307 | wBitCount = 1; |
| 308 | else if (wBitCount <= 4) |
| 309 | wBitCount = 4; |
| 310 | else if (wBitCount <= 8) |
| 311 | wBitCount = 8; |
| 312 | else if (wBitCount <= 16) |
| 313 | wBitCount = 16; |
| 314 | else if (wBitCount <= 24) |
| 315 | wBitCount = 24; |
| 316 | else if (wBitCount <= 32) |
| 317 | wBitCount = 32; |
| 318 | else |
| 319 | wBitCount = 8; /* set default value to 8 if parameter is bogus */ |
| 320 | |
| 321 | dwBytesPerLine = (((wBitCount * dwWidth) + 31) / 32 * 4); |
| 322 | |
| 323 | /* initialize BITMAPINFO */ |
| 324 | bi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER); |
| 325 | bi.bmiHeader.biWidth = dwWidth; |
| 326 | bi.bmiHeader.biHeight = dwHeight; |
| 327 | bi.bmiHeader.biPlanes = 1; /* must be 1 */ |
| 328 | bi.bmiHeader.biBitCount = wBitCount; |
| 329 | bi.bmiHeader.biCompression = compression; |
| 330 | bi.bmiHeader.biSizeImage = dwBytesPerLine*dwHeight; |
| 331 | bi.bmiHeader.biXPelsPerMeter = 0; |
| 332 | bi.bmiHeader.biYPelsPerMeter = 0; |
| 333 | bi.bmiHeader.biClrUsed = wBitCount <= 8 ? 1U << wBitCount : 0; |
| 334 | bi.bmiHeader.biClrImportant = bi.bmiHeader.biClrUsed; |
| 335 | |
| 336 | return bi; |
| 337 | } |
| 338 | |
| 339 | short SwapShort( short in ) |
| 340 | { |
| 341 | char sin[2]; |
| 342 | char sout[2]; |
| 343 | |
| 344 | memcpy( (char *)sin, (char *)&in, 2 ); |
| 345 | |
| 346 | sout[0] = sin[1]; |
| 347 | sout[1] = sin[0]; |
| 348 | |
| 349 | return *((short *)sout); |
| 350 | } |
| 351 | |
| 352 | unsigned short SwapUShort( unsigned short in ) |
| 353 | { |
| 354 | char sin[2]; |
| 355 | char sout[2]; |
| 356 | |
| 357 | memcpy( (char *)sin, (char *)&in, 2 ); |
| 358 | |
| 359 | sout[0] = sin[1]; |
| 360 | sout[1] = sin[0]; |
| 361 | |
| 362 | return *((unsigned short *)sout); |
| 363 | } |
| 364 | |
| 365 | int SwapLong( int in ) |
| 366 | { |
| 367 | char sin[4]; |
| 368 | char sout[4]; |
| 369 | |
| 370 | memcpy( (char *)sin, (char *)&in, 4 ); |
| 371 | |
| 372 | sout[0] = sin[3]; |
| 373 | sout[1] = sin[2]; |
| 374 | sout[2] = sin[1]; |
| 375 | sout[3] = sin[0]; |
| 376 | |
| 377 | return *((int *)sout); |
| 378 | } |
| 379 | |
| 380 | unsigned int SwapULong( unsigned int in ) |
| 381 | { |
| 382 | char sin[4]; |
| 383 | char sout[4]; |
| 384 | |
| 385 | memcpy( (char *)sin, (char *)&in, 4 ); |
| 386 | |
| 387 | sout[0] = sin[3]; |
| 388 | sout[1] = sin[2]; |
| 389 | sout[2] = sin[1]; |
| 390 | sout[3] = sin[0]; |
| 391 | |
| 392 | return *((unsigned int *)sout); |
| 393 | } |
| 394 | |