| 1 | /* |
| 2 | // source code for the BMGImage functions |
| 3 | // |
| 4 | // Copyright (C) 2001 Michael S. Heiman |
| 5 | // |
| 6 | // You may use the software for any purpose you see fit. You may modify |
| 7 | // it, incorporate it in a commercial application, use it for school, |
| 8 | // even turn it in as homework. You must keep the Copyright in the |
| 9 | // header and source files. This software is not in the "Public Domain". |
| 10 | // You may use this software at your own risk. I have made a reasonable |
| 11 | // effort to verify that this software works in the manner I expect it to; |
| 12 | // however,... |
| 13 | // |
| 14 | // THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS" AND |
| 15 | // WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE, INCLUDING |
| 16 | // WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A |
| 17 | // PARTICULAR PURPOSE. IN NO EVENT SHALL MICHAEL S. HEIMAN BE LIABLE TO |
| 18 | // YOU OR ANYONE ELSE FOR ANY DIRECT, SPECIAL, INCIDENTAL, INDIRECT OR |
| 19 | // CONSEQUENTIAL DAMAGES OF ANY KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING |
| 20 | // WITHOUT LIMITATION, LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, |
| 21 | // OR THE CLAIMS OF THIRD PARTIES, WHETHER OR NOT MICHAEL S. HEIMAN HAS |
| 22 | // BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON |
| 23 | // ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE |
| 24 | // POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE. |
| 25 | */ |
| 26 | |
| 27 | #include <memory.h> |
| 28 | #include <setjmp.h> |
| 29 | #include <stdlib.h> |
| 30 | |
| 31 | #include "BMGUtils.h" |
| 32 | |
| 33 | /* initializes a BMGImage to default values */ |
| 34 | void InitBMGImage( struct BMGImageStruct *img ) |
| 35 | { |
| 36 | img->width = img->height = 0; |
| 37 | img->bits_per_pixel = 0; |
| 38 | img->palette_size = 0; |
| 39 | img->bytes_per_palette_entry = 0; |
| 40 | img->bits = NULL; |
| 41 | img->palette = NULL; |
| 42 | img->opt_for_bmp = 0; |
| 43 | img->scan_width = 0; |
| 44 | img->transparency_index = -1; |
| 45 | } |
| 46 | |
| 47 | /* frees memory allocated to a BMGImage */ |
| 48 | void FreeBMGImage( struct BMGImageStruct *img ) |
| 49 | { |
| 50 | if ( img->bits != NULL ) |
| 51 | { |
| 52 | free( img->bits ); |
| 53 | img->bits = NULL; |
| 54 | } |
| 55 | if ( img->palette != NULL ) |
| 56 | { |
| 57 | free( img->palette ); |
| 58 | img->palette = NULL; |
| 59 | } |
| 60 | img->bits_per_pixel = 0; |
| 61 | img->palette_size = 0; |
| 62 | img->bytes_per_palette_entry = 0; |
| 63 | img->width = img->height = 0; |
| 64 | img->opt_for_bmp = 0; |
| 65 | img->scan_width = 0; |
| 66 | img->transparency_index = -1; |
| 67 | } |
| 68 | |
| 69 | /* allocates memory for the bits & palette. Assigned values to scan_line |
| 70 | & bits_per_palette_entry as well. Assumes opt_for_bmp has been set before |
| 71 | this function is called. Assumes that all images with bits_per_pixel <= 8 |
| 72 | require a palette. |
| 73 | */ |
| 74 | BMGError AllocateBMGImage( struct BMGImageStruct *img ) |
| 75 | { |
| 76 | unsigned int mempal; |
| 77 | |
| 78 | SetLastBMGError( BMG_OK ); |
| 79 | |
| 80 | /* make sure that all REQUIRED parameters are valid */ |
| 81 | if ( img->width * img->height <= 0 ) |
| 82 | { |
| 83 | SetLastBMGError(errInvalidSize); |
| 84 | return errInvalidSize; |
| 85 | } |
| 86 | |
| 87 | switch( img->bits_per_pixel ) |
| 88 | { |
| 89 | case 1: |
| 90 | case 4: |
| 91 | case 8: |
| 92 | case 16: |
| 93 | case 24: |
| 94 | case 32: |
| 95 | break; |
| 96 | default: |
| 97 | SetLastBMGError( errInvalidPixelFormat ); |
| 98 | return errInvalidPixelFormat; |
| 99 | } |
| 100 | |
| 101 | /* delete old memory */ |
| 102 | if ( img->bits != NULL ) |
| 103 | { |
| 104 | free( img->bits ); |
| 105 | img->bits = NULL; |
| 106 | } |
| 107 | if ( img->palette != NULL ) |
| 108 | { |
| 109 | free( img->palette ); |
| 110 | img->palette = NULL; |
| 111 | } |
| 112 | |
| 113 | /* allocate memory for the palette */ |
| 114 | if ( img->bits_per_pixel <= 8 ) |
| 115 | { |
| 116 | if ( img->opt_for_bmp > 0 ) |
| 117 | img->bytes_per_palette_entry = 4U; |
| 118 | else |
| 119 | { |
| 120 | /* we only support 3-byte and 4-byte palettes */ |
| 121 | if ( img->bytes_per_palette_entry <= 3U ) |
| 122 | img->bytes_per_palette_entry = 3U; |
| 123 | else |
| 124 | img->bytes_per_palette_entry = 4U; |
| 125 | } |
| 126 | /* |
| 127 | use bits_per_pixel to determine palette_size if none was |
| 128 | specified |
| 129 | */ |
| 130 | if ( img->palette_size == 0 ) |
| 131 | img->palette_size = (unsigned short)(1 << img->bits_per_pixel); |
| 132 | |
| 133 | mempal = img->bytes_per_palette_entry * img->palette_size; |
| 134 | img->palette = (unsigned char *)calloc( mempal, sizeof(unsigned char) ); |
| 135 | if ( img->palette == NULL ) |
| 136 | { |
| 137 | SetLastBMGError(errMemoryAllocation); |
| 138 | return errMemoryAllocation; |
| 139 | } |
| 140 | } |
| 141 | else |
| 142 | { |
| 143 | img->bytes_per_palette_entry = 0; |
| 144 | img->palette_size = 0; |
| 145 | } |
| 146 | |
| 147 | /* |
| 148 | set the scan width. Bitmaps optimized for windows have scan widths that |
| 149 | are evenly divisible by 4. |
| 150 | */ |
| 151 | img->scan_width = ( img->bits_per_pixel * img->width + 7 ) / 8; |
| 152 | if ( img->opt_for_bmp && img->scan_width % 4 ) |
| 153 | img->scan_width += 4 - img->scan_width % 4; |
| 154 | |
| 155 | /* allocate memory for the bits */ |
| 156 | mempal = img->scan_width * img->height; |
| 157 | if ( mempal > 0 ) |
| 158 | { |
| 159 | img->bits = (unsigned char *)calloc( mempal, sizeof( unsigned char) ); |
| 160 | if ( img->bits == NULL ) |
| 161 | { |
| 162 | if ( img->palette != NULL ) |
| 163 | { |
| 164 | free( img->palette ); |
| 165 | img->palette = NULL; |
| 166 | } |
| 167 | SetLastBMGError(errMemoryAllocation); |
| 168 | return errMemoryAllocation; |
| 169 | } |
| 170 | } |
| 171 | else |
| 172 | { |
| 173 | SetLastBMGError(errInvalidSize); |
| 174 | return errInvalidSize; |
| 175 | } |
| 176 | |
| 177 | return BMG_OK; |
| 178 | } |
| 179 | |
| 180 | /******************************************************************************* |
| 181 | A utility function for compressing paletted images. Will automatically |
| 182 | convert 8-bit paletted images to 1-bit or 4-bit paletted images based |
| 183 | upon palette_size. Assumes that indices in img->bits are valid. That is, |
| 184 | 0 <= img->bits[i] <= 1 for all i if 1-bit compression is desired, and |
| 185 | 0 <= img->bits[i] <= 15 for all i if 4-bit compression is desired Returns |
| 186 | BMG_OK if successful, or an error code otherwise. |
| 187 | *******************************************************************************/ |
| 188 | BMGError CompressBMGImage( struct BMGImageStruct *img ) |
| 189 | { |
| 190 | unsigned char new_bits_per_pixel; |
| 191 | unsigned int new_scan_width; |
| 192 | unsigned char *new_bits = NULL; |
| 193 | unsigned int new_bit_size; |
| 194 | unsigned char *new_row, *old_row, *p, *q; |
| 195 | unsigned char *end; |
| 196 | unsigned short scale; |
| 197 | |
| 198 | SetLastBMGError( BMG_OK ); |
| 199 | |
| 200 | /* if we cannot compress it then do no harm and return "true" */ |
| 201 | if ( img->palette == NULL || |
| 202 | img->palette_size > 16 || |
| 203 | img->bits_per_pixel != 8 ) |
| 204 | { |
| 205 | return BMG_OK; |
| 206 | } |
| 207 | |
| 208 | /* calculate new dimensions */ |
| 209 | new_bits_per_pixel = img->palette_size <= 2 ? 1U : 4U; |
| 210 | new_scan_width = ( new_bits_per_pixel * img->width + 7 ) / 8; |
| 211 | if ( img->opt_for_bmp > 0 && new_scan_width % 4 ) |
| 212 | new_scan_width += 4 - new_scan_width % 4; |
| 213 | new_bit_size = new_scan_width * img->height; |
| 214 | |
| 215 | /* allocate & test memory */ |
| 216 | new_bits = (unsigned char *)calloc( new_bit_size, sizeof(unsigned char) ); |
| 217 | if ( new_bits == NULL ) |
| 218 | { |
| 219 | SetLastBMGError( errMemoryAllocation ); |
| 220 | return errMemoryAllocation; |
| 221 | } |
| 222 | |
| 223 | old_row = img->bits; |
| 224 | for ( new_row = new_bits; new_row < new_bits + new_bit_size; |
| 225 | new_row += new_scan_width, old_row += img->scan_width ) |
| 226 | { |
| 227 | scale = 8 / new_bits_per_pixel; |
| 228 | end = new_row + img->width / scale; |
| 229 | p = old_row; |
| 230 | if ( new_bits_per_pixel == 1 ) |
| 231 | { |
| 232 | for ( q = new_row; q < end; q++, p += scale ) |
| 233 | { |
| 234 | *q = (unsigned char)( (p[0] << 7) | (p[1] << 6) | |
| 235 | (p[2] << 5) | (p[3] << 4) | |
| 236 | (p[4] << 3) | (p[5] << 2) | |
| 237 | (p[6] << 1) | p[7] ); |
| 238 | } |
| 239 | scale = img->width % scale; |
| 240 | if ( scale-- > 0 ) |
| 241 | { |
| 242 | *q = (unsigned char)(p[0] << 7); |
| 243 | if ( scale-- ) |
| 244 | { |
| 245 | *q |= (unsigned char)(p[1] << 6); |
| 246 | if ( scale-- ) |
| 247 | { |
| 248 | *q |= (unsigned char)(p[2] << 5); |
| 249 | if ( scale-- ) |
| 250 | { |
| 251 | *q |= (unsigned char)(p[3] << 4); |
| 252 | if ( scale-- ) |
| 253 | { |
| 254 | *q |= (unsigned char)(p[4] << 3); |
| 255 | if ( scale-- ) |
| 256 | { |
| 257 | *q |= (unsigned char)(p[5] << 2); |
| 258 | if ( scale-- ) |
| 259 | *q |= (unsigned char)(p[6] << 1); |
| 260 | } |
| 261 | } |
| 262 | } |
| 263 | } |
| 264 | } |
| 265 | } |
| 266 | } |
| 267 | else /* new_bits_per_pixel == 4 */ |
| 268 | { |
| 269 | for ( q = new_row; q < end; q++, p += scale ) |
| 270 | { |
| 271 | *q = (unsigned char)( (p[0] << 4) | (p[1] & 0x0F) ); |
| 272 | } |
| 273 | if ( img->width % scale ) |
| 274 | *q = (unsigned char)(p[0] << 4); |
| 275 | } |
| 276 | } |
| 277 | |
| 278 | /* replace old values with new values */ |
| 279 | free( img->bits ); |
| 280 | img->bits = new_bits; |
| 281 | img->scan_width = new_scan_width; |
| 282 | img->bits_per_pixel = new_bits_per_pixel; |
| 283 | |
| 284 | return BMG_OK; |
| 285 | } |
| 286 | |
| 287 | /* this function simply frees memory that was allocated by any function |
| 288 | in the BMGLib. This was required because acces violations occurred |
| 289 | when I tried to delete memory created by CreateRGBAArray in the demo |
| 290 | applications */ |
| 291 | void FreeBMGMemory( unsigned char *mem ) |
| 292 | { |
| 293 | if ( mem != NULL ) |
| 294 | free( mem ); |
| 295 | } |
| 296 | |
| 297 | /* converts a BGR to a gray scale |
| 298 | // color[0] = blue, color[1] = green, color[2] = red */ |
| 299 | static unsigned char CreateGrayScale( unsigned char *color ) |
| 300 | { |
| 301 | return (unsigned char)( 0.299f * color[2] + 0.587f * color[1] |
| 302 | + 0.114f * color[0] + 0.5f ); |
| 303 | } |
| 304 | |
| 305 | /* |
| 306 | // converts a color image to a gray scale image. If img is a 16 or |
| 307 | // 24-BPP image then it is converted to a 256 color grayscale bitmap. |
| 308 | // If img is a 1, 4, or 8 BPP image, then it will have the same number |
| 309 | // of grayscales as it has palette entries. If it is a 32-BPP bitmap then |
| 310 | // it will remain a 32-BPP bitmap to preserve the alpha channel. |
| 311 | // |
| 312 | // This function returns BMG_OK if successfull, or an error state |
| 313 | // otherwise. |
| 314 | */ |
| 315 | BMGError ConvertToGrayScale( struct BMGImageStruct *img ) |
| 316 | { |
| 317 | unsigned char *p, *q, *r, *end, gray; |
| 318 | |
| 319 | SetLastBMGError( BMG_OK ); |
| 320 | |
| 321 | /* if this is a paletted image then we simply need to convert the |
| 322 | // palette entries */ |
| 323 | switch ( img->bits_per_pixel ) |
| 324 | { |
| 325 | default: |
| 326 | end = img->palette + img->palette_size * img->bytes_per_palette_entry; |
| 327 | for ( p = img->palette; p < end; p += img->bytes_per_palette_entry ) |
| 328 | { |
| 329 | gray = CreateGrayScale( p ); |
| 330 | memset( (void *)p, gray, 3 ); |
| 331 | } |
| 332 | break; |
| 333 | /* 16 BPP image are converted to 24 BPP images */ |
| 334 | case 16: |
| 335 | { |
| 336 | BMGError tmp = Convert16to24( img ); |
| 337 | if ( tmp != BMG_OK ) |
| 338 | { |
| 339 | SetLastBMGError( tmp ); |
| 340 | return tmp; |
| 341 | } |
| 342 | } |
| 343 | case 24: |
| 344 | { |
| 345 | unsigned char *new_bits; |
| 346 | unsigned char *s, *s_end; |
| 347 | unsigned short i; |
| 348 | |
| 349 | /* calculate the new scan width */ |
| 350 | unsigned int new_scan_width = img->width; |
| 351 | if ( new_scan_width % 4 && img->opt_for_bmp ) |
| 352 | new_scan_width += 4 - new_scan_width % 4; |
| 353 | |
| 354 | /* allocate memory for the new pixel values */ |
| 355 | new_bits = (unsigned char *)calloc( new_scan_width * img->height, |
| 356 | sizeof(unsigned char) ); |
| 357 | if ( new_bits == NULL ) |
| 358 | { |
| 359 | SetLastBMGError( errMemoryAllocation ); |
| 360 | return errMemoryAllocation; |
| 361 | } |
| 362 | |
| 363 | /* allocate memory for a 256 gray scale palette */ |
| 364 | img->bytes_per_palette_entry = img->opt_for_bmp == 1 ? 4 : 3; |
| 365 | img->palette_size = 256; |
| 366 | img->palette = |
| 367 | (unsigned char *)calloc(img->bytes_per_palette_entry * |
| 368 | img->palette_size, |
| 369 | sizeof(unsigned char) ); |
| 370 | if ( img->palette == NULL ) |
| 371 | { |
| 372 | free( new_bits ); |
| 373 | img->bytes_per_palette_entry = 0; |
| 374 | img->palette_size = 0; |
| 375 | SetLastBMGError( errMemoryAllocation ); |
| 376 | return errMemoryAllocation; |
| 377 | } |
| 378 | |
| 379 | /* assign values to the gray scale palette */ |
| 380 | for ( i = 0; i < 256; i++ ) |
| 381 | { |
| 382 | p = img->palette + i * img->bytes_per_palette_entry; |
| 383 | memset( (void *)p, i, 3 ); |
| 384 | if ( img->bytes_per_palette_entry == 4 ) |
| 385 | p[3] = 0; |
| 386 | } |
| 387 | |
| 388 | /* cycle through the pixels and convert them to gray scale values */ |
| 389 | q = new_bits; |
| 390 | end = img->bits + img->scan_width * img->height; |
| 391 | |
| 392 | for ( p = img->bits; p < end; p += img->scan_width, q += new_scan_width ) |
| 393 | { |
| 394 | s_end = p + 3 * img->width; |
| 395 | r = q; |
| 396 | for ( s = p; s < s_end; s += 3, r++ ) |
| 397 | *r = CreateGrayScale( s ); |
| 398 | } |
| 399 | |
| 400 | free( img->bits ); |
| 401 | img->bits = new_bits; |
| 402 | img->scan_width = new_scan_width; |
| 403 | img->bits_per_pixel = 8; |
| 404 | |
| 405 | break; |
| 406 | } |
| 407 | case 32: |
| 408 | end = img->bits + img->scan_width * img->height; |
| 409 | for ( p = img->bits; p < end; p += img->scan_width ) |
| 410 | { |
| 411 | r = p + img->scan_width; |
| 412 | for ( q = p; q < r; q += 4 ) |
| 413 | { |
| 414 | gray = CreateGrayScale( q ); |
| 415 | memset( (void *)q, gray, 3 ); |
| 416 | } |
| 417 | } |
| 418 | break; |
| 419 | } |
| 420 | |
| 421 | return BMG_OK; |
| 422 | } |
| 423 | |
| 424 | /* |
| 425 | // converts a color image to a pseudo-gray scale image. This is a implementation |
| 426 | // is based upon the code published by Rich Franzen |
| 427 | // <http://rocq.home.att.net/pseudoGrey.html>. I have "simplified" the 2 functions |
| 428 | // he published into a single function. This implementation creates 1786 gray |
| 429 | // scales from a 24-bit image. 16-BPP images are converted to 24-BPP images. 24 |
| 430 | // and 32-BPP images will keep the same bitdepth. Paletted images and 16-BPP images |
| 431 | // are not supported. |
| 432 | // |
| 433 | // This function returns BMK_OK if successfull, |
| 434 | // errInvalidPixelFormat otherwise |
| 435 | */ |
| 436 | BMGError ConvertToPseudoGrayScale( struct BMGImageStruct *img ) |
| 437 | { |
| 438 | unsigned char *p, *p_end; |
| 439 | unsigned char *q, *q_end; |
| 440 | unsigned char gray; |
| 441 | unsigned int bytes_per_pixel; |
| 442 | |
| 443 | SetLastBMGError( errMemoryAllocation ); |
| 444 | |
| 445 | if ( img->bits_per_pixel <= 16 ) |
| 446 | { |
| 447 | SetLastBMGError( errInvalidPixelFormat ); |
| 448 | return errInvalidPixelFormat; |
| 449 | } |
| 450 | |
| 451 | bytes_per_pixel = img->bits_per_pixel / 8; |
| 452 | p_end = img->bits + img->scan_width * img->height; |
| 453 | |
| 454 | for ( p = img->bits; p < p_end; p += img->scan_width ) |
| 455 | { |
| 456 | q_end = p + bytes_per_pixel * img->width; |
| 457 | for ( q = p; q < q_end; q += bytes_per_pixel ) |
| 458 | { |
| 459 | /* Rich's code has 1 function that converts an RGB triplet to a float |
| 460 | // bounded by 0 and 1. He has a second function that converts a |
| 461 | // float to a pseudo gray value. Pseudo gray values are RGB triplets |
| 462 | // whose red, green and blue values differ by no more than 1. I have |
| 463 | // combined these two functions into a single function that simply |
| 464 | // looks for pseudo gray RGB triplets. If an RGB triplet meets this |
| 465 | // criteria, I leave it unchanged; otherwise, I use the common intensity |
| 466 | // conversion to create a grayscale value */ |
| 467 | unsigned char cmin, cmax; |
| 468 | |
| 469 | cmin = q[0]; |
| 470 | if ( q[1] < cmin ) |
| 471 | cmin = q[1]; |
| 472 | if ( q[2] < cmin ) |
| 473 | cmin = q[2]; |
| 474 | |
| 475 | cmax = q[0]; |
| 476 | if ( q[1] > cmax ) |
| 477 | cmax = q[1]; |
| 478 | if ( q[2] > cmax ) |
| 479 | cmax = q[2]; |
| 480 | |
| 481 | if ( cmax - cmin > 2 ) |
| 482 | { |
| 483 | gray = CreateGrayScale( q ); |
| 484 | memset( (void *)q, gray, 3 ); |
| 485 | } |
| 486 | } |
| 487 | } |
| 488 | |
| 489 | return BMG_OK; |
| 490 | } |
| 491 | |
| 492 | #ifdef _WIN32 |
| 493 | /******************************************************************************* |
| 494 | // extracts the dimensional information, pixel array, and color table from an |
| 495 | // HBITMAP. |
| 496 | // hBitmap can be a handle to a DIB or a DDB. This function assumes that DDBs |
| 497 | // will not have a palette. If you create a DDB on a 256-color graphics card, |
| 498 | // then the DDB will have a palette and this function will fail. |
| 499 | // |
| 500 | // returns BMK_OK if successfull, and error state otherwise. |
| 501 | ********************************************************************************/ |
| 502 | BMGError GetDataFromBitmap( HBITMAP hBitmap, |
| 503 | struct BMGImageStruct *img, |
| 504 | int remove_alpha ) |
| 505 | { |
| 506 | unsigned int DIBScanWidth; |
| 507 | DIBSECTION DS; |
| 508 | HWND hWnd = GetForegroundWindow(); |
| 509 | HDC hDC = NULL; |
| 510 | HDC hMemDC = NULL; |
| 511 | unsigned char red, green, blue; |
| 512 | int FreelpBits = 0; |
| 513 | unsigned int numBytes; |
| 514 | size_t soDIBSECTION = sizeof(DIBSECTION); |
| 515 | size_t soBITMAP = sizeof(BITMAP); |
| 516 | |
| 517 | unsigned char *p, *q, *lpBits, alpha; |
| 518 | |
| 519 | jmp_buf err_jmp; |
| 520 | int error; |
| 521 | BMGError bmgerr; |
| 522 | |
| 523 | /* error handler */ |
| 524 | error = setjmp( err_jmp ); |
| 525 | if ( error != 0 ) |
| 526 | { |
| 527 | if ( hMemDC != NULL ) |
| 528 | DeleteDC( hMemDC ); |
| 529 | if ( hDC != NULL ) |
| 530 | ReleaseDC( hWnd, hDC ); |
| 531 | if ( FreelpBits ) |
| 532 | free( lpBits ); |
| 533 | FreeBMGImage( img ); |
| 534 | SetLastBMGError( (BMGError)error ); |
| 535 | return (BMGError)error; |
| 536 | } |
| 537 | |
| 538 | SetLastBMGError( BMG_OK ); |
| 539 | /* check for valid bitmap*/ |
| 540 | if ( !hBitmap ) |
| 541 | longjmp( err_jmp, (int)errInvalidBitmapHandle ); |
| 542 | |
| 543 | /* Extract DIBSECTION info from the HBITMAP. numBytes will equal |
| 544 | // soDIBSECTION (84) if hBitmap is a handle to a DIBSECTION (DIB). |
| 545 | // numBytes will equal soBITMAP (24) if hBitmap is a handle to a |
| 546 | // BITMAP (DDB). */ |
| 547 | numBytes = GetObject( hBitmap, sizeof(DIBSECTION), &DS ); |
| 548 | if ( numBytes == 0 ) |
| 549 | longjmp( err_jmp, (int)errWindowsAPI ); |
| 550 | |
| 551 | img->opt_for_bmp = 1; |
| 552 | if ( numBytes == soDIBSECTION ) |
| 553 | { |
| 554 | img->width = DS.dsBmih.biWidth; |
| 555 | img->height = DS.dsBmih.biHeight; |
| 556 | img->bits_per_pixel = (unsigned char)DS.dsBmih.biBitCount; |
| 557 | if ( img->bits_per_pixel <= 8 && DS.dsBmih.biClrUsed > 0 ) |
| 558 | img->palette_size = (unsigned short)DS.dsBmih.biClrUsed; |
| 559 | lpBits = (unsigned char *)DS.dsBm.bmBits; |
| 560 | } |
| 561 | /* this may be a DDB which must be handled differently */ |
| 562 | else if ( numBytes == soBITMAP ) |
| 563 | { |
| 564 | BITMAP bm; |
| 565 | BITMAPINFO bmi; |
| 566 | |
| 567 | if ( GetObject( hBitmap, sizeof(BITMAP), &bm ) == 0 ) |
| 568 | longjmp( err_jmp, (int)errWindowsAPI ); |
| 569 | |
| 570 | /* DDB with a palette */ |
| 571 | if ( bm.bmBitsPixel <= 8 ) |
| 572 | longjmp( err_jmp, (int)errInvalidPixelFormat ); |
| 573 | |
| 574 | img->width = bm.bmWidth; |
| 575 | img->height = bm.bmHeight; |
| 576 | img->bits_per_pixel = (unsigned char)bm.bmBitsPixel; |
| 577 | bmi = InternalCreateBMI( bm.bmWidth, bm.bmHeight, bm.bmBitsPixel, |
| 578 | BI_RGB ); |
| 579 | |
| 580 | lpBits = (unsigned char *)calloc( bm.bmHeight * bm.bmWidthBytes, |
| 581 | sizeof(unsigned char) ); |
| 582 | if ( lpBits == 0 ) |
| 583 | longjmp( err_jmp, (int)errMemoryAllocation ); |
| 584 | FreelpBits = 1; |
| 585 | hDC = GetDC( hWnd ); |
| 586 | if ( GetDIBits(hDC, hBitmap, 0, bm.bmHeight, (void *)lpBits, &bmi, |
| 587 | DIB_RGB_COLORS ) == 0 ) |
| 588 | longjmp( err_jmp, (int)errWindowsAPI ); |
| 589 | ReleaseDC( hWnd, hDC ); |
| 590 | hDC = NULL; |
| 591 | } |
| 592 | else /* I have no idea what this is */ |
| 593 | longjmp( err_jmp, (int)errInvalidBitmapHandle ); |
| 594 | |
| 595 | /* allocate memory */ |
| 596 | bmgerr = AllocateBMGImage( img ); |
| 597 | if ( bmgerr != BMG_OK ) |
| 598 | longjmp( err_jmp, (int)bmgerr ); |
| 599 | |
| 600 | /* dimensions */ |
| 601 | DIBScanWidth = ( img->width * img->bits_per_pixel + 7 )/8; |
| 602 | if ( DIBScanWidth % 4 ) |
| 603 | DIBScanWidth += 4 - DIBScanWidth % 4; |
| 604 | |
| 605 | p = img->bits; |
| 606 | for ( q = lpBits; q < lpBits + DIBScanWidth * img->height; |
| 607 | p += img->scan_width, q += DIBScanWidth ) |
| 608 | { |
| 609 | memcpy( (void *)p, (void *)q, DIBScanWidth ); |
| 610 | } |
| 611 | |
| 612 | /* "un-blend" the image if requested. NOTE: unblending only works with |
| 613 | // bland backgrounds */ |
| 614 | if ( remove_alpha > 0 && |
| 615 | img->bits_per_pixel == 32 && |
| 616 | numBytes == soDIBSECTION ) |
| 617 | { |
| 618 | unsigned char *color = GetBackgroundColor(); |
| 619 | red = color[2]; |
| 620 | green = color[1]; |
| 621 | blue = color[0]; |
| 622 | |
| 623 | for ( p = img->bits; p < img->bits + img->scan_width * img->height; |
| 624 | p += 4 ) |
| 625 | { |
| 626 | alpha = p[3]; |
| 627 | p[2] = InverseAlphaComp( p[2], alpha, blue); |
| 628 | p[1] = InverseAlphaComp( p[1], alpha, green); |
| 629 | p[0] = InverseAlphaComp( p[0], alpha, red); |
| 630 | } |
| 631 | } |
| 632 | |
| 633 | /* 32-bit DDBs must have the alpha channel set to 0xFF before they are |
| 634 | // saved to a file. This may not be true for all devices that generate |
| 635 | // 32-bit DDBs. I have only created 32-bit DDBs using an Intense3D Wildcat |
| 636 | // 4110 card. The alpha channel was always 0. */ |
| 637 | if (img->bits_per_pixel == 32 && numBytes == soBITMAP ) |
| 638 | { |
| 639 | for ( p = img->bits + 3; p < img->bits + img->scan_width * img->height; |
| 640 | p += 4 ) |
| 641 | { |
| 642 | *p = 0xFF; |
| 643 | } |
| 644 | } |
| 645 | |
| 646 | /* create palette if necessary */ |
| 647 | if ( img->bits_per_pixel <= 8 ) |
| 648 | { |
| 649 | hDC = GetDC( hWnd ); |
| 650 | hMemDC = CreateCompatibleDC( hDC ); |
| 651 | SelectObject( hMemDC, hBitmap ); |
| 652 | if ( !GetDIBColorTable( hMemDC, 0, img->palette_size, |
| 653 | (RGBQUAD *)img->palette ) ) |
| 654 | { |
| 655 | longjmp( err_jmp, (int)errWindowsAPI ); |
| 656 | } |
| 657 | DeleteDC( hMemDC ); |
| 658 | ReleaseDC( hWnd, hDC ); |
| 659 | } |
| 660 | |
| 661 | if ( FreelpBits ) |
| 662 | free( lpBits ); |
| 663 | |
| 664 | return BMG_OK; |
| 665 | } |
| 666 | |
| 667 | /******************************************************************************* |
| 668 | // this function creates a bitmap from raw data. Returns an HBITMAP if it |
| 669 | // succeeds, otherwise NULL */ |
| 670 | HBITMAP CreateBitmapFromData( struct BMGImageStruct img, |
| 671 | int alpha_blend ) |
| 672 | { |
| 673 | HBITMAP hBitmap = NULL; |
| 674 | HDC hMemDC = NULL; |
| 675 | HWND hWnd = GetForegroundWindow(); |
| 676 | HDC hDC = NULL; |
| 677 | RGBQUAD *pColor = NULL; |
| 678 | BITMAPINFO bmi; |
| 679 | unsigned char *rbits; |
| 680 | unsigned char *bits; |
| 681 | unsigned char *lpBits; |
| 682 | unsigned char alpha; |
| 683 | unsigned int DIBScanWidth; |
| 684 | int i; |
| 685 | |
| 686 | jmp_buf err_jmp; |
| 687 | int error; |
| 688 | |
| 689 | /* error handler */ |
| 690 | error = setjmp( err_jmp ); |
| 691 | if ( error != 0 ) |
| 692 | { |
| 693 | if ( hMemDC != NULL ) |
| 694 | DeleteDC( hMemDC ); |
| 695 | if ( hDC != NULL ) |
| 696 | ReleaseDC( hWnd, hDC ); |
| 697 | if ( pColor != NULL && img.bytes_per_palette_entry == 3U ) |
| 698 | free( pColor ); |
| 699 | SetLastBMGError( (BMGError)error ); |
| 700 | return 0; |
| 701 | } |
| 702 | |
| 703 | SetLastBMGError( BMG_OK ); |
| 704 | |
| 705 | /* create the DIB section that will hold this bitmap */ |
| 706 | bmi = InternalCreateBMI( (unsigned int)img.width, (unsigned int)img.height, |
| 707 | (unsigned short)img.bits_per_pixel, BI_RGB ); |
| 708 | bmi.bmiHeader.biClrUsed = bmi.bmiHeader.biClrImportant = |
| 709 | img.palette_size; |
| 710 | hDC = GetDC( hWnd ); |
| 711 | hBitmap = CreateDIBSection( hDC, &bmi, DIB_RGB_COLORS, |
| 712 | (void **)&lpBits, NULL, 0 ); |
| 713 | |
| 714 | if ( !hBitmap || !lpBits ) |
| 715 | longjmp( err_jmp, (int)errWindowsAPI ); |
| 716 | |
| 717 | /* create a palette if needed */ |
| 718 | if ( img.palette != NULL ) |
| 719 | { |
| 720 | /* copy pixel data to pColor */ |
| 721 | if ( img.bytes_per_palette_entry == 4U ) |
| 722 | pColor = (RGBQUAD *)img.palette; |
| 723 | else /* bytes_per_palette_entry === 3 */ |
| 724 | { |
| 725 | pColor = (RGBQUAD *)calloc(img.palette_size, sizeof(RGBQUAD) ); |
| 726 | if ( pColor == NULL ) |
| 727 | longjmp( err_jmp, (int)errMemoryAllocation ); |
| 728 | |
| 729 | bits = img.palette; |
| 730 | for ( i = 0; i < (int)bmi.bmiHeader.biClrUsed; i++, bits += 3 ) |
| 731 | { |
| 732 | pColor[i].rgbRed = bits[0]; |
| 733 | pColor[i].rgbGreen = bits[1]; |
| 734 | pColor[i].rgbBlue = bits[2]; |
| 735 | } |
| 736 | } |
| 737 | |
| 738 | if ( img.transparency_index > -1 ) |
| 739 | { |
| 740 | unsigned char *color = GetBackgroundColor(); |
| 741 | rbits = img.palette + img.bytes_per_palette_entry * |
| 742 | img.transparency_index; |
| 743 | rbits[0] = color[2]; |
| 744 | rbits[1] = color[1]; |
| 745 | rbits[2] = color[0]; |
| 746 | } |
| 747 | /* save color table in bitmap */ |
| 748 | hMemDC = CreateCompatibleDC( hDC ); |
| 749 | SelectObject( hMemDC, hBitmap ); |
| 750 | if ( !SetDIBColorTable( hMemDC, 0, img.palette_size, pColor ) ) |
| 751 | longjmp( err_jmp, (int)errWindowsAPI ); |
| 752 | |
| 753 | DeleteDC( hMemDC ); |
| 754 | hMemDC = NULL; |
| 755 | if ( img.bytes_per_palette_entry == 3U ) |
| 756 | free( pColor ); |
| 757 | pColor = NULL; |
| 758 | } |
| 759 | |
| 760 | /* calculate the scan line width */ |
| 761 | DIBScanWidth = img.scan_width; |
| 762 | if ( DIBScanWidth % 4 ) |
| 763 | DIBScanWidth += 4 - DIBScanWidth % 4; |
| 764 | |
| 765 | if ( img.opt_for_bmp == 0 ) |
| 766 | { |
| 767 | /* store bits into hBitmap */ |
| 768 | rbits = img.bits; |
| 769 | for ( bits = lpBits; |
| 770 | bits < lpBits + img.height * DIBScanWidth; |
| 771 | bits += DIBScanWidth, rbits += img.scan_width ) |
| 772 | { |
| 773 | memcpy( (void *)bits, (void *)rbits, img.scan_width ); |
| 774 | } |
| 775 | } |
| 776 | else |
| 777 | memcpy( (void *)lpBits, (void *)img.bits, img.scan_width * img.height ); |
| 778 | |
| 779 | /* blend the image with the window background if alpha pixels |
| 780 | // are present */ |
| 781 | if ( img.bits_per_pixel == 32 ) |
| 782 | { |
| 783 | /* blend with a bland background */ |
| 784 | if ( alpha_blend == 1 ) |
| 785 | { |
| 786 | unsigned char *color = GetBackgroundColor(); |
| 787 | unsigned char red = color[2]; |
| 788 | unsigned char green = color[1]; |
| 789 | unsigned char blue = color[0]; |
| 790 | |
| 791 | for ( rbits = lpBits; |
| 792 | rbits < lpBits + img.height*DIBScanWidth; |
| 793 | rbits += DIBScanWidth ) |
| 794 | { |
| 795 | for ( bits = rbits; bits < rbits + DIBScanWidth; bits += 4 ) |
| 796 | { |
| 797 | alpha = bits[3]; |
| 798 | bits[2] = AlphaComp( bits[2], alpha, blue ); |
| 799 | bits[1] = AlphaComp( bits[1], alpha, green ); |
| 800 | bits[0] = AlphaComp( bits[0], alpha, red ); |
| 801 | } |
| 802 | } |
| 803 | } |
| 804 | /* blend with a background image */ |
| 805 | else if ( alpha_blend == 2 ) |
| 806 | { |
| 807 | unsigned char *bg_bits; |
| 808 | unsigned char *bg_bits_2; |
| 809 | unsigned int bg_bytes_per_pixel; |
| 810 | struct BMGImageStruct *bg = GetBackgroundImage(); |
| 811 | |
| 812 | /* make sure we can blend with a background image |
| 813 | // I assume that the background image is invalid if it does not |
| 814 | // have a valid width */ |
| 815 | if ( bg->width <= 0 || bg->height <= 0 ) |
| 816 | longjmp( err_jmp, (int)errUndefinedBGImage ); |
| 817 | |
| 818 | /* I cannot blend a foreground image with a background image that |
| 819 | // is smaller than it */ |
| 820 | if ( bg->width < img.width || bg->height < img.height ) |
| 821 | longjmp( err_jmp, (int)errBGImageTooSmall ); |
| 822 | |
| 823 | /* the background image was forced to be a 24 or 32-BPP image; |
| 824 | // therefore, we can safely divide by 8 to determined the |
| 825 | // bytes per pixel*/ |
| 826 | bg_bytes_per_pixel = bg->bits_per_pixel / 8; |
| 827 | |
| 828 | /* I will assume that the upper left corner of the input image |
| 829 | // must be aligned with the upper left corner of the background |
| 830 | // image. This allows me to have background images that are bigger |
| 831 | // than the input image. */ |
| 832 | bg_bits = bg->bits; |
| 833 | for ( rbits = lpBits; |
| 834 | rbits < lpBits + img.height*DIBScanWidth; |
| 835 | rbits += DIBScanWidth, bg_bits += bg->scan_width ) |
| 836 | { |
| 837 | bg_bits_2 = bg_bits; |
| 838 | for ( bits = rbits; bits < rbits + DIBScanWidth; |
| 839 | bits += 4, bg_bits_2 += bg_bytes_per_pixel ) |
| 840 | { |
| 841 | alpha = bits[3]; |
| 842 | bits[2] = AlphaComp( bits[2], alpha, bg_bits_2[2] ); |
| 843 | bits[1] = AlphaComp( bits[1], alpha, bg_bits_2[1] ); |
| 844 | bits[0] = AlphaComp( bits[0], alpha, bg_bits_2[0] ); |
| 845 | } |
| 846 | } |
| 847 | |
| 848 | } |
| 849 | } |
| 850 | |
| 851 | ReleaseDC( hWnd, hDC ); |
| 852 | |
| 853 | return hBitmap; |
| 854 | } |
| 855 | #endif // _WIN32 |
| 856 | /****************************************************************************** |
| 857 | // ConvertPaletteToRGB converts paletted and 16-BPP images that do not have |
| 858 | // transparent pixels to 24-BPP images. Paletted images with transparent pixels |
| 859 | // are converted to 32-BPP images. 24-BPP and 32-BPP images are simply copied |
| 860 | // to the output structure |
| 861 | // |
| 862 | // INPUTS: |
| 863 | // img_in |
| 864 | // OUTPUTS: |
| 865 | // img_out |
| 866 | // |
| 867 | // returns BMG_OK if no errors occur, an error code otherwise |
| 868 | ******************************************************************************/ |
| 869 | BMGError ConvertPaletteToRGB( struct BMGImageStruct img_in, |
| 870 | struct BMGImageStruct *img_out ) |
| 871 | { |
| 872 | jmp_buf err_jmp; |
| 873 | int error; |
| 874 | |
| 875 | /* error handler */ |
| 876 | error = setjmp( err_jmp ); |
| 877 | if ( error != 0 ) |
| 878 | { |
| 879 | FreeBMGImage( img_out ); |
| 880 | SetLastBMGError( (BMGError)error ); |
| 881 | return (BMGError)error; |
| 882 | } |
| 883 | |
| 884 | SetLastBMGError( BMG_OK ); |
| 885 | |
| 886 | if ( img_in.height == 0 || img_in.width == 0 ) |
| 887 | longjmp( err_jmp, (int)errInvalidSize ); |
| 888 | |
| 889 | InitBMGImage( img_out ); |
| 890 | |
| 891 | // copy 16, 24, and 32-BPP images into the output image |
| 892 | if ( img_in.bits_per_pixel > 8 ) |
| 893 | { |
| 894 | BMGError out; |
| 895 | img_out->bits_per_pixel = img_in.bits_per_pixel; |
| 896 | out = CopyBMGImage( img_in, img_out ); |
| 897 | if ( out != BMG_OK ) |
| 898 | longjmp( err_jmp, (int)out ); |
| 899 | |
| 900 | // 16-BPP are converted to 24-BPP images |
| 901 | if ( img_out->bits_per_pixel == 16 ) |
| 902 | { |
| 903 | out = Convert16to24( img_out ); |
| 904 | if ( out != BMG_OK ) |
| 905 | longjmp( err_jmp, (int)out ); |
| 906 | } |
| 907 | } |
| 908 | else // convert paletted images to 24-BPP BGR or 32-BPP BGRA images |
| 909 | { |
| 910 | BMGError out; |
| 911 | unsigned char *buf; |
| 912 | unsigned int scan_width; |
| 913 | int dealloc; |
| 914 | unsigned char *q0, *q1, *p0, *p1; |
| 915 | unsigned int bpp; |
| 916 | |
| 917 | // allocate memory for the 24-BPP output image |
| 918 | img_out->width = img_in.width; |
| 919 | img_out->height = img_in.height; |
| 920 | img_out->opt_for_bmp = img_in.opt_for_bmp; |
| 921 | img_out->bits_per_pixel = img_in.transparency_index > -1 ? 32 : 24; |
| 922 | |
| 923 | out = AllocateBMGImage( img_out ); |
| 924 | if ( out != BMG_OK ) |
| 925 | longjmp( err_jmp, (int)out ); |
| 926 | |
| 927 | // 1-BPP and 4-BPP images are packed, so we need to unpack them |
| 928 | if ( img_in.bits_per_pixel < 8 ) |
| 929 | { |
| 930 | dealloc = 1; |
| 931 | scan_width = img_in.width; |
| 932 | buf = (unsigned char *)malloc(scan_width * img_in.height); |
| 933 | if ( buf == NULL ) |
| 934 | longjmp( err_jmp, (int)errMemoryAllocation ); |
| 935 | |
| 936 | if ( img_in.bits_per_pixel == 1 ) |
| 937 | Convert1to8( img_in, buf ); |
| 938 | else |
| 939 | Convert4to8( img_in, buf ); |
| 940 | } |
| 941 | else // simply point to the bits array if we have a 8-BPP image |
| 942 | { |
| 943 | dealloc = 0; |
| 944 | buf = img_in.bits; |
| 945 | scan_width = img_in.scan_width; |
| 946 | } |
| 947 | |
| 948 | // convert palette indices to BGR pixels |
| 949 | bpp = img_out->bits_per_pixel / 8; |
| 950 | q0 = img_out->bits; |
| 951 | for ( p0 = buf; p0 < buf + scan_width * img_in.height; |
| 952 | p0 += scan_width, q0 += img_out->scan_width ) |
| 953 | { |
| 954 | q1 = q0; |
| 955 | for ( p1 = p0; p1 < p0 + img_in.width; p1++, q1 += bpp ) |
| 956 | { |
| 957 | memcpy( (void *)q1, |
| 958 | (void *)(img_in.palette + *p1 * img_in.bytes_per_palette_entry), 3 ); |
| 959 | if ( bpp == 4 ) |
| 960 | { |
| 961 | q1[3] = *p1 == img_in.transparency_index ? 0 : 0xFF; |
| 962 | } |
| 963 | } |
| 964 | } |
| 965 | |
| 966 | if ( dealloc == 1 ) |
| 967 | free( buf ); |
| 968 | } |
| 969 | |
| 970 | return BMG_OK; |
| 971 | } |
| 972 | |
| 973 | /****************************************************************************** |
| 974 | // CopyBMG copies the contents of img_in into img_out. |
| 975 | // |
| 976 | // CopyBMG returns BMG_OK if successful, otherwise, it returns an error code |
| 977 | ******************************************************************************/ |
| 978 | BMGError CopyBMGImage( struct BMGImageStruct img_in, |
| 979 | struct BMGImageStruct *img_out ) |
| 980 | { |
| 981 | BMGError out = BMG_OK; |
| 982 | SetLastBMGError( out ); |
| 983 | |
| 984 | FreeBMGImage( img_out ); |
| 985 | |
| 986 | img_out->height = img_in.height; |
| 987 | img_out->width = img_in.width; |
| 988 | img_out->bits_per_pixel = img_in.bits_per_pixel; |
| 989 | img_out->palette_size = img_in.palette_size; |
| 990 | img_out->opt_for_bmp = img_in.opt_for_bmp; |
| 991 | |
| 992 | if ( img_in.width > 0 && img_in.height > 0 ) |
| 993 | { |
| 994 | out = AllocateBMGImage( img_out ); |
| 995 | if ( out == BMG_OK ) |
| 996 | { |
| 997 | memcpy( (void *)img_out->bits, (void *)img_in.bits, |
| 998 | img_in.scan_width * img_in.height ); |
| 999 | if ( img_in.palette_size > 0 ) |
| 1000 | memcpy( (void *)img_out->palette, (void *)img_in.palette, |
| 1001 | img_in.palette_size * img_in.bytes_per_palette_entry ); |
| 1002 | } |
| 1003 | } |
| 1004 | |
| 1005 | return out; |
| 1006 | } |
| 1007 | |
| 1008 | /* sets the background color for alpha blending |
| 1009 | color points to an array of 4 unsigned chars |
| 1010 | color[0] = blue, color[1] = green, color[2] = red, color[3] = unused */ |
| 1011 | void SetBMGBackgroundColor( unsigned char *color ) |
| 1012 | { |
| 1013 | memcpy( (void *)GetBackgroundColor(), (void *)color, |
| 1014 | 4*sizeof(unsigned char) ); |
| 1015 | } |
| 1016 | |
| 1017 | #ifdef _WIN32 |
| 1018 | /* defines the background bitmap that is used for alpha blending & transparent |
| 1019 | pixels */ |
| 1020 | BMGError SetBMGBackgroundBitmap( HBITMAP hBitmap ) |
| 1021 | { |
| 1022 | BMGError out; |
| 1023 | struct BMGImageStruct tmp; |
| 1024 | InitBMGImage( &tmp ); |
| 1025 | |
| 1026 | /* first we extract the data from the HBITMAP */ |
| 1027 | out = GetDataFromBitmap( hBitmap, &tmp, 0 ); |
| 1028 | if ( out == BMG_OK ) |
| 1029 | { |
| 1030 | /* clean up the old background image */ |
| 1031 | FreeBMGImage( GetBackgroundImage() ); |
| 1032 | |
| 1033 | /* next, we convert paletted & 16-BPP images to 24 or 32-BPP images. |
| 1034 | // this will simplify the alpha blending. */ |
| 1035 | out = ConvertPaletteToRGB( tmp, GetBackgroundImage() ); |
| 1036 | } |
| 1037 | |
| 1038 | return out; |
| 1039 | } |
| 1040 | #endif // _WIN32 |
| 1041 | |
| 1042 | /* defines the background image that is used for alpha blending & transparent |
| 1043 | pixels */ |
| 1044 | BMGError SetBMGBackgroundImage( struct BMGImageStruct img ) |
| 1045 | { |
| 1046 | /* clean up the old background image */ |
| 1047 | FreeBMGImage( GetBackgroundImage() ); |
| 1048 | |
| 1049 | /* convert paletted and 16-BPP images to 24-BPP or 32-BPP images. This |
| 1050 | // will simplify the alpha blending logic*/ |
| 1051 | return ConvertPaletteToRGB( img, GetBackgroundImage() ); |
| 1052 | } |
| 1053 | |