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diff --git a/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jquant1.c b/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jquant1.c new file mode 100644 index 0000000..1c482bc --- /dev/null +++ b/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jquant1.c | |||
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1 | /* | ||
2 | * jquant1.c | ||
3 | * | ||
4 | * Copyright (C) 1991-1996, Thomas G. Lane. | ||
5 | * Modified 2011 by Guido Vollbeding. | ||
6 | * This file is part of the Independent JPEG Group's software. | ||
7 | * For conditions of distribution and use, see the accompanying README file. | ||
8 | * | ||
9 | * This file contains 1-pass color quantization (color mapping) routines. | ||
10 | * These routines provide mapping to a fixed color map using equally spaced | ||
11 | * color values. Optional Floyd-Steinberg or ordered dithering is available. | ||
12 | */ | ||
13 | |||
14 | #define JPEG_INTERNALS | ||
15 | #include "jinclude.h" | ||
16 | #include "jpeglib.h" | ||
17 | |||
18 | #ifdef QUANT_1PASS_SUPPORTED | ||
19 | |||
20 | |||
21 | /* | ||
22 | * The main purpose of 1-pass quantization is to provide a fast, if not very | ||
23 | * high quality, colormapped output capability. A 2-pass quantizer usually | ||
24 | * gives better visual quality; however, for quantized grayscale output this | ||
25 | * quantizer is perfectly adequate. Dithering is highly recommended with this | ||
26 | * quantizer, though you can turn it off if you really want to. | ||
27 | * | ||
28 | * In 1-pass quantization the colormap must be chosen in advance of seeing the | ||
29 | * image. We use a map consisting of all combinations of Ncolors[i] color | ||
30 | * values for the i'th component. The Ncolors[] values are chosen so that | ||
31 | * their product, the total number of colors, is no more than that requested. | ||
32 | * (In most cases, the product will be somewhat less.) | ||
33 | * | ||
34 | * Since the colormap is orthogonal, the representative value for each color | ||
35 | * component can be determined without considering the other components; | ||
36 | * then these indexes can be combined into a colormap index by a standard | ||
37 | * N-dimensional-array-subscript calculation. Most of the arithmetic involved | ||
38 | * can be precalculated and stored in the lookup table colorindex[]. | ||
39 | * colorindex[i][j] maps pixel value j in component i to the nearest | ||
40 | * representative value (grid plane) for that component; this index is | ||
41 | * multiplied by the array stride for component i, so that the | ||
42 | * index of the colormap entry closest to a given pixel value is just | ||
43 | * sum( colorindex[component-number][pixel-component-value] ) | ||
44 | * Aside from being fast, this scheme allows for variable spacing between | ||
45 | * representative values with no additional lookup cost. | ||
46 | * | ||
47 | * If gamma correction has been applied in color conversion, it might be wise | ||
48 | * to adjust the color grid spacing so that the representative colors are | ||
49 | * equidistant in linear space. At this writing, gamma correction is not | ||
50 | * implemented by jdcolor, so nothing is done here. | ||
51 | */ | ||
52 | |||
53 | |||
54 | /* Declarations for ordered dithering. | ||
55 | * | ||
56 | * We use a standard 16x16 ordered dither array. The basic concept of ordered | ||
57 | * dithering is described in many references, for instance Dale Schumacher's | ||
58 | * chapter II.2 of Graphics Gems II (James Arvo, ed. Academic Press, 1991). | ||
59 | * In place of Schumacher's comparisons against a "threshold" value, we add a | ||
60 | * "dither" value to the input pixel and then round the result to the nearest | ||
61 | * output value. The dither value is equivalent to (0.5 - threshold) times | ||
62 | * the distance between output values. For ordered dithering, we assume that | ||
63 | * the output colors are equally spaced; if not, results will probably be | ||
64 | * worse, since the dither may be too much or too little at a given point. | ||
65 | * | ||
66 | * The normal calculation would be to form pixel value + dither, range-limit | ||
67 | * this to 0..MAXJSAMPLE, and then index into the colorindex table as usual. | ||
68 | * We can skip the separate range-limiting step by extending the colorindex | ||
69 | * table in both directions. | ||
70 | */ | ||
71 | |||
72 | #define ODITHER_SIZE 16 /* dimension of dither matrix */ | ||
73 | /* NB: if ODITHER_SIZE is not a power of 2, ODITHER_MASK uses will break */ | ||
74 | #define ODITHER_CELLS (ODITHER_SIZE*ODITHER_SIZE) /* # cells in matrix */ | ||
75 | #define ODITHER_MASK (ODITHER_SIZE-1) /* mask for wrapping around counters */ | ||
76 | |||
77 | typedef int ODITHER_MATRIX[ODITHER_SIZE][ODITHER_SIZE]; | ||
78 | typedef int (*ODITHER_MATRIX_PTR)[ODITHER_SIZE]; | ||
79 | |||
80 | static const UINT8 base_dither_matrix[ODITHER_SIZE][ODITHER_SIZE] = { | ||
81 | /* Bayer's order-4 dither array. Generated by the code given in | ||
82 | * Stephen Hawley's article "Ordered Dithering" in Graphics Gems I. | ||
83 | * The values in this array must range from 0 to ODITHER_CELLS-1. | ||
84 | */ | ||
85 | { 0,192, 48,240, 12,204, 60,252, 3,195, 51,243, 15,207, 63,255 }, | ||
86 | { 128, 64,176,112,140, 76,188,124,131, 67,179,115,143, 79,191,127 }, | ||
87 | { 32,224, 16,208, 44,236, 28,220, 35,227, 19,211, 47,239, 31,223 }, | ||
88 | { 160, 96,144, 80,172,108,156, 92,163, 99,147, 83,175,111,159, 95 }, | ||
89 | { 8,200, 56,248, 4,196, 52,244, 11,203, 59,251, 7,199, 55,247 }, | ||
90 | { 136, 72,184,120,132, 68,180,116,139, 75,187,123,135, 71,183,119 }, | ||
91 | { 40,232, 24,216, 36,228, 20,212, 43,235, 27,219, 39,231, 23,215 }, | ||
92 | { 168,104,152, 88,164,100,148, 84,171,107,155, 91,167,103,151, 87 }, | ||
93 | { 2,194, 50,242, 14,206, 62,254, 1,193, 49,241, 13,205, 61,253 }, | ||
94 | { 130, 66,178,114,142, 78,190,126,129, 65,177,113,141, 77,189,125 }, | ||
95 | { 34,226, 18,210, 46,238, 30,222, 33,225, 17,209, 45,237, 29,221 }, | ||
96 | { 162, 98,146, 82,174,110,158, 94,161, 97,145, 81,173,109,157, 93 }, | ||
97 | { 10,202, 58,250, 6,198, 54,246, 9,201, 57,249, 5,197, 53,245 }, | ||
98 | { 138, 74,186,122,134, 70,182,118,137, 73,185,121,133, 69,181,117 }, | ||
99 | { 42,234, 26,218, 38,230, 22,214, 41,233, 25,217, 37,229, 21,213 }, | ||
100 | { 170,106,154, 90,166,102,150, 86,169,105,153, 89,165,101,149, 85 } | ||
101 | }; | ||
102 | |||
103 | |||
104 | /* Declarations for Floyd-Steinberg dithering. | ||
105 | * | ||
106 | * Errors are accumulated into the array fserrors[], at a resolution of | ||
107 | * 1/16th of a pixel count. The error at a given pixel is propagated | ||
108 | * to its not-yet-processed neighbors using the standard F-S fractions, | ||
109 | * ... (here) 7/16 | ||
110 | * 3/16 5/16 1/16 | ||
111 | * We work left-to-right on even rows, right-to-left on odd rows. | ||
112 | * | ||
113 | * We can get away with a single array (holding one row's worth of errors) | ||
114 | * by using it to store the current row's errors at pixel columns not yet | ||
115 | * processed, but the next row's errors at columns already processed. We | ||
116 | * need only a few extra variables to hold the errors immediately around the | ||
117 | * current column. (If we are lucky, those variables are in registers, but | ||
118 | * even if not, they're probably cheaper to access than array elements are.) | ||
119 | * | ||
120 | * The fserrors[] array is indexed [component#][position]. | ||
121 | * We provide (#columns + 2) entries per component; the extra entry at each | ||
122 | * end saves us from special-casing the first and last pixels. | ||
123 | * | ||
124 | * Note: on a wide image, we might not have enough room in a PC's near data | ||
125 | * segment to hold the error array; so it is allocated with alloc_large. | ||
126 | */ | ||
127 | |||
128 | #if BITS_IN_JSAMPLE == 8 | ||
129 | typedef INT16 FSERROR; /* 16 bits should be enough */ | ||
130 | typedef int LOCFSERROR; /* use 'int' for calculation temps */ | ||
131 | #else | ||
132 | typedef INT32 FSERROR; /* may need more than 16 bits */ | ||
133 | typedef INT32 LOCFSERROR; /* be sure calculation temps are big enough */ | ||
134 | #endif | ||
135 | |||
136 | typedef FSERROR FAR *FSERRPTR; /* pointer to error array (in FAR storage!) */ | ||
137 | |||
138 | |||
139 | /* Private subobject */ | ||
140 | |||
141 | #define MAX_Q_COMPS 4 /* max components I can handle */ | ||
142 | |||
143 | typedef struct { | ||
144 | struct jpeg_color_quantizer pub; /* public fields */ | ||
145 | |||
146 | /* Initially allocated colormap is saved here */ | ||
147 | JSAMPARRAY sv_colormap; /* The color map as a 2-D pixel array */ | ||
148 | int sv_actual; /* number of entries in use */ | ||
149 | |||
150 | JSAMPARRAY colorindex; /* Precomputed mapping for speed */ | ||
151 | /* colorindex[i][j] = index of color closest to pixel value j in component i, | ||
152 | * premultiplied as described above. Since colormap indexes must fit into | ||
153 | * JSAMPLEs, the entries of this array will too. | ||
154 | */ | ||
155 | boolean is_padded; /* is the colorindex padded for odither? */ | ||
156 | |||
157 | int Ncolors[MAX_Q_COMPS]; /* # of values alloced to each component */ | ||
158 | |||
159 | /* Variables for ordered dithering */ | ||
160 | int row_index; /* cur row's vertical index in dither matrix */ | ||
161 | ODITHER_MATRIX_PTR odither[MAX_Q_COMPS]; /* one dither array per component */ | ||
162 | |||
163 | /* Variables for Floyd-Steinberg dithering */ | ||
164 | FSERRPTR fserrors[MAX_Q_COMPS]; /* accumulated errors */ | ||
165 | boolean on_odd_row; /* flag to remember which row we are on */ | ||
166 | } my_cquantizer; | ||
167 | |||
168 | typedef my_cquantizer * my_cquantize_ptr; | ||
169 | |||
170 | |||
171 | /* | ||
172 | * Policy-making subroutines for create_colormap and create_colorindex. | ||
173 | * These routines determine the colormap to be used. The rest of the module | ||
174 | * only assumes that the colormap is orthogonal. | ||
175 | * | ||
176 | * * select_ncolors decides how to divvy up the available colors | ||
177 | * among the components. | ||
178 | * * output_value defines the set of representative values for a component. | ||
179 | * * largest_input_value defines the mapping from input values to | ||
180 | * representative values for a component. | ||
181 | * Note that the latter two routines may impose different policies for | ||
182 | * different components, though this is not currently done. | ||
183 | */ | ||
184 | |||
185 | |||
186 | LOCAL(int) | ||
187 | select_ncolors (j_decompress_ptr cinfo, int Ncolors[]) | ||
188 | /* Determine allocation of desired colors to components, */ | ||
189 | /* and fill in Ncolors[] array to indicate choice. */ | ||
190 | /* Return value is total number of colors (product of Ncolors[] values). */ | ||
191 | { | ||
192 | int nc = cinfo->out_color_components; /* number of color components */ | ||
193 | int max_colors = cinfo->desired_number_of_colors; | ||
194 | int total_colors, iroot, i, j; | ||
195 | boolean changed; | ||
196 | long temp; | ||
197 | static const int RGB_order[3] = { RGB_GREEN, RGB_RED, RGB_BLUE }; | ||
198 | |||
199 | /* We can allocate at least the nc'th root of max_colors per component. */ | ||
200 | /* Compute floor(nc'th root of max_colors). */ | ||
201 | iroot = 1; | ||
202 | do { | ||
203 | iroot++; | ||
204 | temp = iroot; /* set temp = iroot ** nc */ | ||
205 | for (i = 1; i < nc; i++) | ||
206 | temp *= iroot; | ||
207 | } while (temp <= (long) max_colors); /* repeat till iroot exceeds root */ | ||
208 | iroot--; /* now iroot = floor(root) */ | ||
209 | |||
210 | /* Must have at least 2 color values per component */ | ||
211 | if (iroot < 2) | ||
212 | ERREXIT1(cinfo, JERR_QUANT_FEW_COLORS, (int) temp); | ||
213 | |||
214 | /* Initialize to iroot color values for each component */ | ||
215 | total_colors = 1; | ||
216 | for (i = 0; i < nc; i++) { | ||
217 | Ncolors[i] = iroot; | ||
218 | total_colors *= iroot; | ||
219 | } | ||
220 | /* We may be able to increment the count for one or more components without | ||
221 | * exceeding max_colors, though we know not all can be incremented. | ||
222 | * Sometimes, the first component can be incremented more than once! | ||
223 | * (Example: for 16 colors, we start at 2*2*2, go to 3*2*2, then 4*2*2.) | ||
224 | * In RGB colorspace, try to increment G first, then R, then B. | ||
225 | */ | ||
226 | do { | ||
227 | changed = FALSE; | ||
228 | for (i = 0; i < nc; i++) { | ||
229 | j = (cinfo->out_color_space == JCS_RGB ? RGB_order[i] : i); | ||
230 | /* calculate new total_colors if Ncolors[j] is incremented */ | ||
231 | temp = total_colors / Ncolors[j]; | ||
232 | temp *= Ncolors[j]+1; /* done in long arith to avoid oflo */ | ||
233 | if (temp > (long) max_colors) | ||
234 | break; /* won't fit, done with this pass */ | ||
235 | Ncolors[j]++; /* OK, apply the increment */ | ||
236 | total_colors = (int) temp; | ||
237 | changed = TRUE; | ||
238 | } | ||
239 | } while (changed); | ||
240 | |||
241 | return total_colors; | ||
242 | } | ||
243 | |||
244 | |||
245 | LOCAL(int) | ||
246 | output_value (j_decompress_ptr cinfo, int ci, int j, int maxj) | ||
247 | /* Return j'th output value, where j will range from 0 to maxj */ | ||
248 | /* The output values must fall in 0..MAXJSAMPLE in increasing order */ | ||
249 | { | ||
250 | /* We always provide values 0 and MAXJSAMPLE for each component; | ||
251 | * any additional values are equally spaced between these limits. | ||
252 | * (Forcing the upper and lower values to the limits ensures that | ||
253 | * dithering can't produce a color outside the selected gamut.) | ||
254 | */ | ||
255 | return (int) (((INT32) j * MAXJSAMPLE + maxj/2) / maxj); | ||
256 | } | ||
257 | |||
258 | |||
259 | LOCAL(int) | ||
260 | largest_input_value (j_decompress_ptr cinfo, int ci, int j, int maxj) | ||
261 | /* Return largest input value that should map to j'th output value */ | ||
262 | /* Must have largest(j=0) >= 0, and largest(j=maxj) >= MAXJSAMPLE */ | ||
263 | { | ||
264 | /* Breakpoints are halfway between values returned by output_value */ | ||
265 | return (int) (((INT32) (2*j + 1) * MAXJSAMPLE + maxj) / (2*maxj)); | ||
266 | } | ||
267 | |||
268 | |||
269 | /* | ||
270 | * Create the colormap. | ||
271 | */ | ||
272 | |||
273 | LOCAL(void) | ||
274 | create_colormap (j_decompress_ptr cinfo) | ||
275 | { | ||
276 | my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; | ||
277 | JSAMPARRAY colormap; /* Created colormap */ | ||
278 | int total_colors; /* Number of distinct output colors */ | ||
279 | int i,j,k, nci, blksize, blkdist, ptr, val; | ||
280 | |||
281 | /* Select number of colors for each component */ | ||
282 | total_colors = select_ncolors(cinfo, cquantize->Ncolors); | ||
283 | |||
284 | /* Report selected color counts */ | ||
285 | if (cinfo->out_color_components == 3) | ||
286 | TRACEMS4(cinfo, 1, JTRC_QUANT_3_NCOLORS, | ||
287 | total_colors, cquantize->Ncolors[0], | ||
288 | cquantize->Ncolors[1], cquantize->Ncolors[2]); | ||
289 | else | ||
290 | TRACEMS1(cinfo, 1, JTRC_QUANT_NCOLORS, total_colors); | ||
291 | |||
292 | /* Allocate and fill in the colormap. */ | ||
293 | /* The colors are ordered in the map in standard row-major order, */ | ||
294 | /* i.e. rightmost (highest-indexed) color changes most rapidly. */ | ||
295 | |||
296 | colormap = (*cinfo->mem->alloc_sarray) | ||
297 | ((j_common_ptr) cinfo, JPOOL_IMAGE, | ||
298 | (JDIMENSION) total_colors, (JDIMENSION) cinfo->out_color_components); | ||
299 | |||
300 | /* blksize is number of adjacent repeated entries for a component */ | ||
301 | /* blkdist is distance between groups of identical entries for a component */ | ||
302 | blkdist = total_colors; | ||
303 | |||
304 | for (i = 0; i < cinfo->out_color_components; i++) { | ||
305 | /* fill in colormap entries for i'th color component */ | ||
306 | nci = cquantize->Ncolors[i]; /* # of distinct values for this color */ | ||
307 | blksize = blkdist / nci; | ||
308 | for (j = 0; j < nci; j++) { | ||
309 | /* Compute j'th output value (out of nci) for component */ | ||
310 | val = output_value(cinfo, i, j, nci-1); | ||
311 | /* Fill in all colormap entries that have this value of this component */ | ||
312 | for (ptr = j * blksize; ptr < total_colors; ptr += blkdist) { | ||
313 | /* fill in blksize entries beginning at ptr */ | ||
314 | for (k = 0; k < blksize; k++) | ||
315 | colormap[i][ptr+k] = (JSAMPLE) val; | ||
316 | } | ||
317 | } | ||
318 | blkdist = blksize; /* blksize of this color is blkdist of next */ | ||
319 | } | ||
320 | |||
321 | /* Save the colormap in private storage, | ||
322 | * where it will survive color quantization mode changes. | ||
323 | */ | ||
324 | cquantize->sv_colormap = colormap; | ||
325 | cquantize->sv_actual = total_colors; | ||
326 | } | ||
327 | |||
328 | |||
329 | /* | ||
330 | * Create the color index table. | ||
331 | */ | ||
332 | |||
333 | LOCAL(void) | ||
334 | create_colorindex (j_decompress_ptr cinfo) | ||
335 | { | ||
336 | my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; | ||
337 | JSAMPROW indexptr; | ||
338 | int i,j,k, nci, blksize, val, pad; | ||
339 | |||
340 | /* For ordered dither, we pad the color index tables by MAXJSAMPLE in | ||
341 | * each direction (input index values can be -MAXJSAMPLE .. 2*MAXJSAMPLE). | ||
342 | * This is not necessary in the other dithering modes. However, we | ||
343 | * flag whether it was done in case user changes dithering mode. | ||
344 | */ | ||
345 | if (cinfo->dither_mode == JDITHER_ORDERED) { | ||
346 | pad = MAXJSAMPLE*2; | ||
347 | cquantize->is_padded = TRUE; | ||
348 | } else { | ||
349 | pad = 0; | ||
350 | cquantize->is_padded = FALSE; | ||
351 | } | ||
352 | |||
353 | cquantize->colorindex = (*cinfo->mem->alloc_sarray) | ||
354 | ((j_common_ptr) cinfo, JPOOL_IMAGE, | ||
355 | (JDIMENSION) (MAXJSAMPLE+1 + pad), | ||
356 | (JDIMENSION) cinfo->out_color_components); | ||
357 | |||
358 | /* blksize is number of adjacent repeated entries for a component */ | ||
359 | blksize = cquantize->sv_actual; | ||
360 | |||
361 | for (i = 0; i < cinfo->out_color_components; i++) { | ||
362 | /* fill in colorindex entries for i'th color component */ | ||
363 | nci = cquantize->Ncolors[i]; /* # of distinct values for this color */ | ||
364 | blksize = blksize / nci; | ||
365 | |||
366 | /* adjust colorindex pointers to provide padding at negative indexes. */ | ||
367 | if (pad) | ||
368 | cquantize->colorindex[i] += MAXJSAMPLE; | ||
369 | |||
370 | /* in loop, val = index of current output value, */ | ||
371 | /* and k = largest j that maps to current val */ | ||
372 | indexptr = cquantize->colorindex[i]; | ||
373 | val = 0; | ||
374 | k = largest_input_value(cinfo, i, 0, nci-1); | ||
375 | for (j = 0; j <= MAXJSAMPLE; j++) { | ||
376 | while (j > k) /* advance val if past boundary */ | ||
377 | k = largest_input_value(cinfo, i, ++val, nci-1); | ||
378 | /* premultiply so that no multiplication needed in main processing */ | ||
379 | indexptr[j] = (JSAMPLE) (val * blksize); | ||
380 | } | ||
381 | /* Pad at both ends if necessary */ | ||
382 | if (pad) | ||
383 | for (j = 1; j <= MAXJSAMPLE; j++) { | ||
384 | indexptr[-j] = indexptr[0]; | ||
385 | indexptr[MAXJSAMPLE+j] = indexptr[MAXJSAMPLE]; | ||
386 | } | ||
387 | } | ||
388 | } | ||
389 | |||
390 | |||
391 | /* | ||
392 | * Create an ordered-dither array for a component having ncolors | ||
393 | * distinct output values. | ||
394 | */ | ||
395 | |||
396 | LOCAL(ODITHER_MATRIX_PTR) | ||
397 | make_odither_array (j_decompress_ptr cinfo, int ncolors) | ||
398 | { | ||
399 | ODITHER_MATRIX_PTR odither; | ||
400 | int j,k; | ||
401 | INT32 num,den; | ||
402 | |||
403 | odither = (ODITHER_MATRIX_PTR) | ||
404 | (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, | ||
405 | SIZEOF(ODITHER_MATRIX)); | ||
406 | /* The inter-value distance for this color is MAXJSAMPLE/(ncolors-1). | ||
407 | * Hence the dither value for the matrix cell with fill order f | ||
408 | * (f=0..N-1) should be (N-1-2*f)/(2*N) * MAXJSAMPLE/(ncolors-1). | ||
409 | * On 16-bit-int machine, be careful to avoid overflow. | ||
410 | */ | ||
411 | den = 2 * ODITHER_CELLS * ((INT32) (ncolors - 1)); | ||
412 | for (j = 0; j < ODITHER_SIZE; j++) { | ||
413 | for (k = 0; k < ODITHER_SIZE; k++) { | ||
414 | num = ((INT32) (ODITHER_CELLS-1 - 2*((int)base_dither_matrix[j][k]))) | ||
415 | * MAXJSAMPLE; | ||
416 | /* Ensure round towards zero despite C's lack of consistency | ||
417 | * about rounding negative values in integer division... | ||
418 | */ | ||
419 | odither[j][k] = (int) (num<0 ? -((-num)/den) : num/den); | ||
420 | } | ||
421 | } | ||
422 | return odither; | ||
423 | } | ||
424 | |||
425 | |||
426 | /* | ||
427 | * Create the ordered-dither tables. | ||
428 | * Components having the same number of representative colors may | ||
429 | * share a dither table. | ||
430 | */ | ||
431 | |||
432 | LOCAL(void) | ||
433 | create_odither_tables (j_decompress_ptr cinfo) | ||
434 | { | ||
435 | my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; | ||
436 | ODITHER_MATRIX_PTR odither; | ||
437 | int i, j, nci; | ||
438 | |||
439 | for (i = 0; i < cinfo->out_color_components; i++) { | ||
440 | nci = cquantize->Ncolors[i]; /* # of distinct values for this color */ | ||
441 | odither = NULL; /* search for matching prior component */ | ||
442 | for (j = 0; j < i; j++) { | ||
443 | if (nci == cquantize->Ncolors[j]) { | ||
444 | odither = cquantize->odither[j]; | ||
445 | break; | ||
446 | } | ||
447 | } | ||
448 | if (odither == NULL) /* need a new table? */ | ||
449 | odither = make_odither_array(cinfo, nci); | ||
450 | cquantize->odither[i] = odither; | ||
451 | } | ||
452 | } | ||
453 | |||
454 | |||
455 | /* | ||
456 | * Map some rows of pixels to the output colormapped representation. | ||
457 | */ | ||
458 | |||
459 | METHODDEF(void) | ||
460 | color_quantize (j_decompress_ptr cinfo, JSAMPARRAY input_buf, | ||
461 | JSAMPARRAY output_buf, int num_rows) | ||
462 | /* General case, no dithering */ | ||
463 | { | ||
464 | my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; | ||
465 | JSAMPARRAY colorindex = cquantize->colorindex; | ||
466 | register int pixcode, ci; | ||
467 | register JSAMPROW ptrin, ptrout; | ||
468 | int row; | ||
469 | JDIMENSION col; | ||
470 | JDIMENSION width = cinfo->output_width; | ||
471 | register int nc = cinfo->out_color_components; | ||
472 | |||
473 | for (row = 0; row < num_rows; row++) { | ||
474 | ptrin = input_buf[row]; | ||
475 | ptrout = output_buf[row]; | ||
476 | for (col = width; col > 0; col--) { | ||
477 | pixcode = 0; | ||
478 | for (ci = 0; ci < nc; ci++) { | ||
479 | pixcode += GETJSAMPLE(colorindex[ci][GETJSAMPLE(*ptrin++)]); | ||
480 | } | ||
481 | *ptrout++ = (JSAMPLE) pixcode; | ||
482 | } | ||
483 | } | ||
484 | } | ||
485 | |||
486 | |||
487 | METHODDEF(void) | ||
488 | color_quantize3 (j_decompress_ptr cinfo, JSAMPARRAY input_buf, | ||
489 | JSAMPARRAY output_buf, int num_rows) | ||
490 | /* Fast path for out_color_components==3, no dithering */ | ||
491 | { | ||
492 | my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; | ||
493 | register int pixcode; | ||
494 | register JSAMPROW ptrin, ptrout; | ||
495 | JSAMPROW colorindex0 = cquantize->colorindex[0]; | ||
496 | JSAMPROW colorindex1 = cquantize->colorindex[1]; | ||
497 | JSAMPROW colorindex2 = cquantize->colorindex[2]; | ||
498 | int row; | ||
499 | JDIMENSION col; | ||
500 | JDIMENSION width = cinfo->output_width; | ||
501 | |||
502 | for (row = 0; row < num_rows; row++) { | ||
503 | ptrin = input_buf[row]; | ||
504 | ptrout = output_buf[row]; | ||
505 | for (col = width; col > 0; col--) { | ||
506 | pixcode = GETJSAMPLE(colorindex0[GETJSAMPLE(*ptrin++)]); | ||
507 | pixcode += GETJSAMPLE(colorindex1[GETJSAMPLE(*ptrin++)]); | ||
508 | pixcode += GETJSAMPLE(colorindex2[GETJSAMPLE(*ptrin++)]); | ||
509 | *ptrout++ = (JSAMPLE) pixcode; | ||
510 | } | ||
511 | } | ||
512 | } | ||
513 | |||
514 | |||
515 | METHODDEF(void) | ||
516 | quantize_ord_dither (j_decompress_ptr cinfo, JSAMPARRAY input_buf, | ||
517 | JSAMPARRAY output_buf, int num_rows) | ||
518 | /* General case, with ordered dithering */ | ||
519 | { | ||
520 | my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; | ||
521 | register JSAMPROW input_ptr; | ||
522 | register JSAMPROW output_ptr; | ||
523 | JSAMPROW colorindex_ci; | ||
524 | int * dither; /* points to active row of dither matrix */ | ||
525 | int row_index, col_index; /* current indexes into dither matrix */ | ||
526 | int nc = cinfo->out_color_components; | ||
527 | int ci; | ||
528 | int row; | ||
529 | JDIMENSION col; | ||
530 | JDIMENSION width = cinfo->output_width; | ||
531 | |||
532 | for (row = 0; row < num_rows; row++) { | ||
533 | /* Initialize output values to 0 so can process components separately */ | ||
534 | FMEMZERO((void FAR *) output_buf[row], | ||
535 | (size_t) (width * SIZEOF(JSAMPLE))); | ||
536 | row_index = cquantize->row_index; | ||
537 | for (ci = 0; ci < nc; ci++) { | ||
538 | input_ptr = input_buf[row] + ci; | ||
539 | output_ptr = output_buf[row]; | ||
540 | colorindex_ci = cquantize->colorindex[ci]; | ||
541 | dither = cquantize->odither[ci][row_index]; | ||
542 | col_index = 0; | ||
543 | |||
544 | for (col = width; col > 0; col--) { | ||
545 | /* Form pixel value + dither, range-limit to 0..MAXJSAMPLE, | ||
546 | * select output value, accumulate into output code for this pixel. | ||
547 | * Range-limiting need not be done explicitly, as we have extended | ||
548 | * the colorindex table to produce the right answers for out-of-range | ||
549 | * inputs. The maximum dither is +- MAXJSAMPLE; this sets the | ||
550 | * required amount of padding. | ||
551 | */ | ||
552 | *output_ptr += colorindex_ci[GETJSAMPLE(*input_ptr)+dither[col_index]]; | ||
553 | input_ptr += nc; | ||
554 | output_ptr++; | ||
555 | col_index = (col_index + 1) & ODITHER_MASK; | ||
556 | } | ||
557 | } | ||
558 | /* Advance row index for next row */ | ||
559 | row_index = (row_index + 1) & ODITHER_MASK; | ||
560 | cquantize->row_index = row_index; | ||
561 | } | ||
562 | } | ||
563 | |||
564 | |||
565 | METHODDEF(void) | ||
566 | quantize3_ord_dither (j_decompress_ptr cinfo, JSAMPARRAY input_buf, | ||
567 | JSAMPARRAY output_buf, int num_rows) | ||
568 | /* Fast path for out_color_components==3, with ordered dithering */ | ||
569 | { | ||
570 | my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; | ||
571 | register int pixcode; | ||
572 | register JSAMPROW input_ptr; | ||
573 | register JSAMPROW output_ptr; | ||
574 | JSAMPROW colorindex0 = cquantize->colorindex[0]; | ||
575 | JSAMPROW colorindex1 = cquantize->colorindex[1]; | ||
576 | JSAMPROW colorindex2 = cquantize->colorindex[2]; | ||
577 | int * dither0; /* points to active row of dither matrix */ | ||
578 | int * dither1; | ||
579 | int * dither2; | ||
580 | int row_index, col_index; /* current indexes into dither matrix */ | ||
581 | int row; | ||
582 | JDIMENSION col; | ||
583 | JDIMENSION width = cinfo->output_width; | ||
584 | |||
585 | for (row = 0; row < num_rows; row++) { | ||
586 | row_index = cquantize->row_index; | ||
587 | input_ptr = input_buf[row]; | ||
588 | output_ptr = output_buf[row]; | ||
589 | dither0 = cquantize->odither[0][row_index]; | ||
590 | dither1 = cquantize->odither[1][row_index]; | ||
591 | dither2 = cquantize->odither[2][row_index]; | ||
592 | col_index = 0; | ||
593 | |||
594 | for (col = width; col > 0; col--) { | ||
595 | pixcode = GETJSAMPLE(colorindex0[GETJSAMPLE(*input_ptr++) + | ||
596 | dither0[col_index]]); | ||
597 | pixcode += GETJSAMPLE(colorindex1[GETJSAMPLE(*input_ptr++) + | ||
598 | dither1[col_index]]); | ||
599 | pixcode += GETJSAMPLE(colorindex2[GETJSAMPLE(*input_ptr++) + | ||
600 | dither2[col_index]]); | ||
601 | *output_ptr++ = (JSAMPLE) pixcode; | ||
602 | col_index = (col_index + 1) & ODITHER_MASK; | ||
603 | } | ||
604 | row_index = (row_index + 1) & ODITHER_MASK; | ||
605 | cquantize->row_index = row_index; | ||
606 | } | ||
607 | } | ||
608 | |||
609 | |||
610 | METHODDEF(void) | ||
611 | quantize_fs_dither (j_decompress_ptr cinfo, JSAMPARRAY input_buf, | ||
612 | JSAMPARRAY output_buf, int num_rows) | ||
613 | /* General case, with Floyd-Steinberg dithering */ | ||
614 | { | ||
615 | my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; | ||
616 | register LOCFSERROR cur; /* current error or pixel value */ | ||
617 | LOCFSERROR belowerr; /* error for pixel below cur */ | ||
618 | LOCFSERROR bpreverr; /* error for below/prev col */ | ||
619 | LOCFSERROR bnexterr; /* error for below/next col */ | ||
620 | LOCFSERROR delta; | ||
621 | register FSERRPTR errorptr; /* => fserrors[] at column before current */ | ||
622 | register JSAMPROW input_ptr; | ||
623 | register JSAMPROW output_ptr; | ||
624 | JSAMPROW colorindex_ci; | ||
625 | JSAMPROW colormap_ci; | ||
626 | int pixcode; | ||
627 | int nc = cinfo->out_color_components; | ||
628 | int dir; /* 1 for left-to-right, -1 for right-to-left */ | ||
629 | int dirnc; /* dir * nc */ | ||
630 | int ci; | ||
631 | int row; | ||
632 | JDIMENSION col; | ||
633 | JDIMENSION width = cinfo->output_width; | ||
634 | JSAMPLE *range_limit = cinfo->sample_range_limit; | ||
635 | SHIFT_TEMPS | ||
636 | |||
637 | for (row = 0; row < num_rows; row++) { | ||
638 | /* Initialize output values to 0 so can process components separately */ | ||
639 | FMEMZERO((void FAR *) output_buf[row], | ||
640 | (size_t) (width * SIZEOF(JSAMPLE))); | ||
641 | for (ci = 0; ci < nc; ci++) { | ||
642 | input_ptr = input_buf[row] + ci; | ||
643 | output_ptr = output_buf[row]; | ||
644 | if (cquantize->on_odd_row) { | ||
645 | /* work right to left in this row */ | ||
646 | input_ptr += (width-1) * nc; /* so point to rightmost pixel */ | ||
647 | output_ptr += width-1; | ||
648 | dir = -1; | ||
649 | dirnc = -nc; | ||
650 | errorptr = cquantize->fserrors[ci] + (width+1); /* => entry after last column */ | ||
651 | } else { | ||
652 | /* work left to right in this row */ | ||
653 | dir = 1; | ||
654 | dirnc = nc; | ||
655 | errorptr = cquantize->fserrors[ci]; /* => entry before first column */ | ||
656 | } | ||
657 | colorindex_ci = cquantize->colorindex[ci]; | ||
658 | colormap_ci = cquantize->sv_colormap[ci]; | ||
659 | /* Preset error values: no error propagated to first pixel from left */ | ||
660 | cur = 0; | ||
661 | /* and no error propagated to row below yet */ | ||
662 | belowerr = bpreverr = 0; | ||
663 | |||
664 | for (col = width; col > 0; col--) { | ||
665 | /* cur holds the error propagated from the previous pixel on the | ||
666 | * current line. Add the error propagated from the previous line | ||
667 | * to form the complete error correction term for this pixel, and | ||
668 | * round the error term (which is expressed * 16) to an integer. | ||
669 | * RIGHT_SHIFT rounds towards minus infinity, so adding 8 is correct | ||
670 | * for either sign of the error value. | ||
671 | * Note: errorptr points to *previous* column's array entry. | ||
672 | */ | ||
673 | cur = RIGHT_SHIFT(cur + errorptr[dir] + 8, 4); | ||
674 | /* Form pixel value + error, and range-limit to 0..MAXJSAMPLE. | ||
675 | * The maximum error is +- MAXJSAMPLE; this sets the required size | ||
676 | * of the range_limit array. | ||
677 | */ | ||
678 | cur += GETJSAMPLE(*input_ptr); | ||
679 | cur = GETJSAMPLE(range_limit[cur]); | ||
680 | /* Select output value, accumulate into output code for this pixel */ | ||
681 | pixcode = GETJSAMPLE(colorindex_ci[cur]); | ||
682 | *output_ptr += (JSAMPLE) pixcode; | ||
683 | /* Compute actual representation error at this pixel */ | ||
684 | /* Note: we can do this even though we don't have the final */ | ||
685 | /* pixel code, because the colormap is orthogonal. */ | ||
686 | cur -= GETJSAMPLE(colormap_ci[pixcode]); | ||
687 | /* Compute error fractions to be propagated to adjacent pixels. | ||
688 | * Add these into the running sums, and simultaneously shift the | ||
689 | * next-line error sums left by 1 column. | ||
690 | */ | ||
691 | bnexterr = cur; | ||
692 | delta = cur * 2; | ||
693 | cur += delta; /* form error * 3 */ | ||
694 | errorptr[0] = (FSERROR) (bpreverr + cur); | ||
695 | cur += delta; /* form error * 5 */ | ||
696 | bpreverr = belowerr + cur; | ||
697 | belowerr = bnexterr; | ||
698 | cur += delta; /* form error * 7 */ | ||
699 | /* At this point cur contains the 7/16 error value to be propagated | ||
700 | * to the next pixel on the current line, and all the errors for the | ||
701 | * next line have been shifted over. We are therefore ready to move on. | ||
702 | */ | ||
703 | input_ptr += dirnc; /* advance input ptr to next column */ | ||
704 | output_ptr += dir; /* advance output ptr to next column */ | ||
705 | errorptr += dir; /* advance errorptr to current column */ | ||
706 | } | ||
707 | /* Post-loop cleanup: we must unload the final error value into the | ||
708 | * final fserrors[] entry. Note we need not unload belowerr because | ||
709 | * it is for the dummy column before or after the actual array. | ||
710 | */ | ||
711 | errorptr[0] = (FSERROR) bpreverr; /* unload prev err into array */ | ||
712 | } | ||
713 | cquantize->on_odd_row = (cquantize->on_odd_row ? FALSE : TRUE); | ||
714 | } | ||
715 | } | ||
716 | |||
717 | |||
718 | /* | ||
719 | * Allocate workspace for Floyd-Steinberg errors. | ||
720 | */ | ||
721 | |||
722 | LOCAL(void) | ||
723 | alloc_fs_workspace (j_decompress_ptr cinfo) | ||
724 | { | ||
725 | my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; | ||
726 | size_t arraysize; | ||
727 | int i; | ||
728 | |||
729 | arraysize = (size_t) ((cinfo->output_width + 2) * SIZEOF(FSERROR)); | ||
730 | for (i = 0; i < cinfo->out_color_components; i++) { | ||
731 | cquantize->fserrors[i] = (FSERRPTR) | ||
732 | (*cinfo->mem->alloc_large)((j_common_ptr) cinfo, JPOOL_IMAGE, arraysize); | ||
733 | } | ||
734 | } | ||
735 | |||
736 | |||
737 | /* | ||
738 | * Initialize for one-pass color quantization. | ||
739 | */ | ||
740 | |||
741 | METHODDEF(void) | ||
742 | start_pass_1_quant (j_decompress_ptr cinfo, boolean is_pre_scan) | ||
743 | { | ||
744 | my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; | ||
745 | size_t arraysize; | ||
746 | int i; | ||
747 | |||
748 | /* Install my colormap. */ | ||
749 | cinfo->colormap = cquantize->sv_colormap; | ||
750 | cinfo->actual_number_of_colors = cquantize->sv_actual; | ||
751 | |||
752 | /* Initialize for desired dithering mode. */ | ||
753 | switch (cinfo->dither_mode) { | ||
754 | case JDITHER_NONE: | ||
755 | if (cinfo->out_color_components == 3) | ||
756 | cquantize->pub.color_quantize = color_quantize3; | ||
757 | else | ||
758 | cquantize->pub.color_quantize = color_quantize; | ||
759 | break; | ||
760 | case JDITHER_ORDERED: | ||
761 | if (cinfo->out_color_components == 3) | ||
762 | cquantize->pub.color_quantize = quantize3_ord_dither; | ||
763 | else | ||
764 | cquantize->pub.color_quantize = quantize_ord_dither; | ||
765 | cquantize->row_index = 0; /* initialize state for ordered dither */ | ||
766 | /* If user changed to ordered dither from another mode, | ||
767 | * we must recreate the color index table with padding. | ||
768 | * This will cost extra space, but probably isn't very likely. | ||
769 | */ | ||
770 | if (! cquantize->is_padded) | ||
771 | create_colorindex(cinfo); | ||
772 | /* Create ordered-dither tables if we didn't already. */ | ||
773 | if (cquantize->odither[0] == NULL) | ||
774 | create_odither_tables(cinfo); | ||
775 | break; | ||
776 | case JDITHER_FS: | ||
777 | cquantize->pub.color_quantize = quantize_fs_dither; | ||
778 | cquantize->on_odd_row = FALSE; /* initialize state for F-S dither */ | ||
779 | /* Allocate Floyd-Steinberg workspace if didn't already. */ | ||
780 | if (cquantize->fserrors[0] == NULL) | ||
781 | alloc_fs_workspace(cinfo); | ||
782 | /* Initialize the propagated errors to zero. */ | ||
783 | arraysize = (size_t) ((cinfo->output_width + 2) * SIZEOF(FSERROR)); | ||
784 | for (i = 0; i < cinfo->out_color_components; i++) | ||
785 | FMEMZERO((void FAR *) cquantize->fserrors[i], arraysize); | ||
786 | break; | ||
787 | default: | ||
788 | ERREXIT(cinfo, JERR_NOT_COMPILED); | ||
789 | break; | ||
790 | } | ||
791 | } | ||
792 | |||
793 | |||
794 | /* | ||
795 | * Finish up at the end of the pass. | ||
796 | */ | ||
797 | |||
798 | METHODDEF(void) | ||
799 | finish_pass_1_quant (j_decompress_ptr cinfo) | ||
800 | { | ||
801 | /* no work in 1-pass case */ | ||
802 | } | ||
803 | |||
804 | |||
805 | /* | ||
806 | * Switch to a new external colormap between output passes. | ||
807 | * Shouldn't get to this module! | ||
808 | */ | ||
809 | |||
810 | METHODDEF(void) | ||
811 | new_color_map_1_quant (j_decompress_ptr cinfo) | ||
812 | { | ||
813 | ERREXIT(cinfo, JERR_MODE_CHANGE); | ||
814 | } | ||
815 | |||
816 | |||
817 | /* | ||
818 | * Module initialization routine for 1-pass color quantization. | ||
819 | */ | ||
820 | |||
821 | GLOBAL(void) | ||
822 | jinit_1pass_quantizer (j_decompress_ptr cinfo) | ||
823 | { | ||
824 | my_cquantize_ptr cquantize; | ||
825 | |||
826 | cquantize = (my_cquantize_ptr) | ||
827 | (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, | ||
828 | SIZEOF(my_cquantizer)); | ||
829 | cinfo->cquantize = (struct jpeg_color_quantizer *) cquantize; | ||
830 | cquantize->pub.start_pass = start_pass_1_quant; | ||
831 | cquantize->pub.finish_pass = finish_pass_1_quant; | ||
832 | cquantize->pub.new_color_map = new_color_map_1_quant; | ||
833 | cquantize->fserrors[0] = NULL; /* Flag FS workspace not allocated */ | ||
834 | cquantize->odither[0] = NULL; /* Also flag odither arrays not allocated */ | ||
835 | |||
836 | /* Make sure my internal arrays won't overflow */ | ||
837 | if (cinfo->out_color_components > MAX_Q_COMPS) | ||
838 | ERREXIT1(cinfo, JERR_QUANT_COMPONENTS, MAX_Q_COMPS); | ||
839 | /* Make sure colormap indexes can be represented by JSAMPLEs */ | ||
840 | if (cinfo->desired_number_of_colors > (MAXJSAMPLE+1)) | ||
841 | ERREXIT1(cinfo, JERR_QUANT_MANY_COLORS, MAXJSAMPLE+1); | ||
842 | |||
843 | /* Create the colormap and color index table. */ | ||
844 | create_colormap(cinfo); | ||
845 | create_colorindex(cinfo); | ||
846 | |||
847 | /* Allocate Floyd-Steinberg workspace now if requested. | ||
848 | * We do this now since it is FAR storage and may affect the memory | ||
849 | * manager's space calculations. If the user changes to FS dither | ||
850 | * mode in a later pass, we will allocate the space then, and will | ||
851 | * possibly overrun the max_memory_to_use setting. | ||
852 | */ | ||
853 | if (cinfo->dither_mode == JDITHER_FS) | ||
854 | alloc_fs_workspace(cinfo); | ||
855 | } | ||
856 | |||
857 | #endif /* QUANT_1PASS_SUPPORTED */ | ||