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Issue 1953443002: Update to libjpeg_turbo 1.4.90 (Closed) Base URL: https://chromium.googlesource.com/chromium/deps/libjpeg_turbo.git@master
Patch Set: Created 4 years, 7 months ago
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1 /* 1 /*
2 * jquant2.c 2 * jquant2.c
3 * 3 *
4 * This file was part of the Independent JPEG Group's software: 4 * This file was part of the Independent JPEG Group's software:
5 * Copyright (C) 1991-1996, Thomas G. Lane. 5 * Copyright (C) 1991-1996, Thomas G. Lane.
6 * libjpeg-turbo Modifications: 6 * libjpeg-turbo Modifications:
7 * Copyright (C) 2009, D. R. Commander. 7 * Copyright (C) 2009, 2014-2015, D. R. Commander.
8 * For conditions of distribution and use, see the accompanying README file. 8 * For conditions of distribution and use, see the accompanying README.ijg
9 * file.
9 * 10 *
10 * This file contains 2-pass color quantization (color mapping) routines. 11 * This file contains 2-pass color quantization (color mapping) routines.
11 * These routines provide selection of a custom color map for an image, 12 * These routines provide selection of a custom color map for an image,
12 * followed by mapping of the image to that color map, with optional 13 * followed by mapping of the image to that color map, with optional
13 * Floyd-Steinberg dithering. 14 * Floyd-Steinberg dithering.
14 * It is also possible to use just the second pass to map to an arbitrary 15 * It is also possible to use just the second pass to map to an arbitrary
15 * externally-given color map. 16 * externally-given color map.
16 * 17 *
17 * Note: ordered dithering is not supported, since there isn't any fast 18 * Note: ordered dithering is not supported, since there isn't any fast
18 * way to compute intercolor distances; it's unclear that ordered dither's 19 * way to compute intercolor distances; it's unclear that ordered dither's
(...skipping 17 matching lines...) Expand all
36 * In the first pass over the image, we accumulate a histogram showing the 37 * In the first pass over the image, we accumulate a histogram showing the
37 * usage count of each possible color. To keep the histogram to a reasonable 38 * usage count of each possible color. To keep the histogram to a reasonable
38 * size, we reduce the precision of the input; typical practice is to retain 39 * size, we reduce the precision of the input; typical practice is to retain
39 * 5 or 6 bits per color, so that 8 or 4 different input values are counted 40 * 5 or 6 bits per color, so that 8 or 4 different input values are counted
40 * in the same histogram cell. 41 * in the same histogram cell.
41 * 42 *
42 * Next, the color-selection step begins with a box representing the whole 43 * Next, the color-selection step begins with a box representing the whole
43 * color space, and repeatedly splits the "largest" remaining box until we 44 * color space, and repeatedly splits the "largest" remaining box until we
44 * have as many boxes as desired colors. Then the mean color in each 45 * have as many boxes as desired colors. Then the mean color in each
45 * remaining box becomes one of the possible output colors. 46 * remaining box becomes one of the possible output colors.
46 * 47 *
47 * The second pass over the image maps each input pixel to the closest output 48 * The second pass over the image maps each input pixel to the closest output
48 * color (optionally after applying a Floyd-Steinberg dithering correction). 49 * color (optionally after applying a Floyd-Steinberg dithering correction).
49 * This mapping is logically trivial, but making it go fast enough requires 50 * This mapping is logically trivial, but making it go fast enough requires
50 * considerable care. 51 * considerable care.
51 * 52 *
52 * Heckbert-style quantizers vary a good deal in their policies for choosing 53 * Heckbert-style quantizers vary a good deal in their policies for choosing
53 * the "largest" box and deciding where to cut it. The particular policies 54 * the "largest" box and deciding where to cut it. The particular policies
54 * used here have proved out well in experimental comparisons, but better ones 55 * used here have proved out well in experimental comparisons, but better ones
55 * may yet be found. 56 * may yet be found.
56 * 57 *
57 * In earlier versions of the IJG code, this module quantized in YCbCr color 58 * In earlier versions of the IJG code, this module quantized in YCbCr color
58 * space, processing the raw upsampled data without a color conversion step. 59 * space, processing the raw upsampled data without a color conversion step.
59 * This allowed the color conversion math to be done only once per colormap 60 * This allowed the color conversion math to be done only once per colormap
60 * entry, not once per pixel. However, that optimization precluded other 61 * entry, not once per pixel. However, that optimization precluded other
61 * useful optimizations (such as merging color conversion with upsampling) 62 * useful optimizations (such as merging color conversion with upsampling)
62 * and it also interfered with desired capabilities such as quantizing to an 63 * and it also interfered with desired capabilities such as quantizing to an
63 * externally-supplied colormap. We have therefore abandoned that approach. 64 * externally-supplied colormap. We have therefore abandoned that approach.
64 * The present code works in the post-conversion color space, typically RGB. 65 * The present code works in the post-conversion color space, typically RGB.
65 * 66 *
66 * To improve the visual quality of the results, we actually work in scaled 67 * To improve the visual quality of the results, we actually work in scaled
67 * RGB space, giving G distances more weight than R, and R in turn more than 68 * RGB space, giving G distances more weight than R, and R in turn more than
68 * B. To do everything in integer math, we must use integer scale factors. 69 * B. To do everything in integer math, we must use integer scale factors.
69 * The 2/3/1 scale factors used here correspond loosely to the relative 70 * The 2/3/1 scale factors used here correspond loosely to the relative
70 * weights of the colors in the NTSC grayscale equation. 71 * weights of the colors in the NTSC grayscale equation.
71 * If you want to use this code to quantize a non-RGB color space, you'll 72 * If you want to use this code to quantize a non-RGB color space, you'll
72 * probably need to change these scale factors. 73 * probably need to change these scale factors.
73 */ 74 */
74 75
75 #define R_SCALE 2» » /* scale R distances by this much */ 76 #define R_SCALE 2 /* scale R distances by this much */
76 #define G_SCALE 3» » /* scale G distances by this much */ 77 #define G_SCALE 3 /* scale G distances by this much */
77 #define B_SCALE 1» » /* and B by this much */ 78 #define B_SCALE 1 /* and B by this much */
78 79
79 static const int c_scales[3]={R_SCALE, G_SCALE, B_SCALE}; 80 static const int c_scales[3]={R_SCALE, G_SCALE, B_SCALE};
80 #define C0_SCALE c_scales[rgb_red[cinfo->out_color_space]] 81 #define C0_SCALE c_scales[rgb_red[cinfo->out_color_space]]
81 #define C1_SCALE c_scales[rgb_green[cinfo->out_color_space]] 82 #define C1_SCALE c_scales[rgb_green[cinfo->out_color_space]]
82 #define C2_SCALE c_scales[rgb_blue[cinfo->out_color_space]] 83 #define C2_SCALE c_scales[rgb_blue[cinfo->out_color_space]]
83 84
84 /* 85 /*
85 * First we have the histogram data structure and routines for creating it. 86 * First we have the histogram data structure and routines for creating it.
86 * 87 *
87 * The number of bits of precision can be adjusted by changing these symbols. 88 * The number of bits of precision can be adjusted by changing these symbols.
88 * We recommend keeping 6 bits for G and 5 each for R and B. 89 * We recommend keeping 6 bits for G and 5 each for R and B.
89 * If you have plenty of memory and cycles, 6 bits all around gives marginally 90 * If you have plenty of memory and cycles, 6 bits all around gives marginally
90 * better results; if you are short of memory, 5 bits all around will save 91 * better results; if you are short of memory, 5 bits all around will save
91 * some space but degrade the results. 92 * some space but degrade the results.
92 * To maintain a fully accurate histogram, we'd need to allocate a "long" 93 * To maintain a fully accurate histogram, we'd need to allocate a "long"
93 * (preferably unsigned long) for each cell. In practice this is overkill; 94 * (preferably unsigned long) for each cell. In practice this is overkill;
94 * we can get by with 16 bits per cell. Few of the cell counts will overflow, 95 * we can get by with 16 bits per cell. Few of the cell counts will overflow,
95 * and clamping those that do overflow to the maximum value will give close- 96 * and clamping those that do overflow to the maximum value will give close-
96 * enough results. This reduces the recommended histogram size from 256Kb 97 * enough results. This reduces the recommended histogram size from 256Kb
97 * to 128Kb, which is a useful savings on PC-class machines. 98 * to 128Kb, which is a useful savings on PC-class machines.
98 * (In the second pass the histogram space is re-used for pixel mapping data; 99 * (In the second pass the histogram space is re-used for pixel mapping data;
99 * in that capacity, each cell must be able to store zero to the number of 100 * in that capacity, each cell must be able to store zero to the number of
100 * desired colors. 16 bits/cell is plenty for that too.) 101 * desired colors. 16 bits/cell is plenty for that too.)
101 * Since the JPEG code is intended to run in small memory model on 80x86 102 * Since the JPEG code is intended to run in small memory model on 80x86
102 * machines, we can't just allocate the histogram in one chunk. Instead 103 * machines, we can't just allocate the histogram in one chunk. Instead
103 * of a true 3-D array, we use a row of pointers to 2-D arrays. Each 104 * of a true 3-D array, we use a row of pointers to 2-D arrays. Each
104 * pointer corresponds to a C0 value (typically 2^5 = 32 pointers) and 105 * pointer corresponds to a C0 value (typically 2^5 = 32 pointers) and
105 * each 2-D array has 2^6*2^5 = 2048 or 2^6*2^6 = 4096 entries. Note that 106 * each 2-D array has 2^6*2^5 = 2048 or 2^6*2^6 = 4096 entries.
106 * on 80x86 machines, the pointer row is in near memory but the actual
107 * arrays are in far memory (same arrangement as we use for image arrays).
108 */ 107 */
109 108
110 #define MAXNUMCOLORS (MAXJSAMPLE+1) /* maximum size of colormap */ 109 #define MAXNUMCOLORS (MAXJSAMPLE+1) /* maximum size of colormap */
111 110
112 /* These will do the right thing for either R,G,B or B,G,R color order, 111 /* These will do the right thing for either R,G,B or B,G,R color order,
113 * but you may not like the results for other color orders. 112 * but you may not like the results for other color orders.
114 */ 113 */
115 #define HIST_C0_BITS 5»» /* bits of precision in R/B histogram */ 114 #define HIST_C0_BITS 5 /* bits of precision in R/B histogram */
116 #define HIST_C1_BITS 6»» /* bits of precision in G histogram */ 115 #define HIST_C1_BITS 6 /* bits of precision in G histogram */
117 #define HIST_C2_BITS 5»» /* bits of precision in B/R histogram */ 116 #define HIST_C2_BITS 5 /* bits of precision in B/R histogram */
118 117
119 /* Number of elements along histogram axes. */ 118 /* Number of elements along histogram axes. */
120 #define HIST_C0_ELEMS (1<<HIST_C0_BITS) 119 #define HIST_C0_ELEMS (1<<HIST_C0_BITS)
121 #define HIST_C1_ELEMS (1<<HIST_C1_BITS) 120 #define HIST_C1_ELEMS (1<<HIST_C1_BITS)
122 #define HIST_C2_ELEMS (1<<HIST_C2_BITS) 121 #define HIST_C2_ELEMS (1<<HIST_C2_BITS)
123 122
124 /* These are the amounts to shift an input value to get a histogram index. */ 123 /* These are the amounts to shift an input value to get a histogram index. */
125 #define C0_SHIFT (BITS_IN_JSAMPLE-HIST_C0_BITS) 124 #define C0_SHIFT (BITS_IN_JSAMPLE-HIST_C0_BITS)
126 #define C1_SHIFT (BITS_IN_JSAMPLE-HIST_C1_BITS) 125 #define C1_SHIFT (BITS_IN_JSAMPLE-HIST_C1_BITS)
127 #define C2_SHIFT (BITS_IN_JSAMPLE-HIST_C2_BITS) 126 #define C2_SHIFT (BITS_IN_JSAMPLE-HIST_C2_BITS)
128 127
129 128
130 typedef UINT16 histcell;» /* histogram cell; prefer an unsigned type */ 129 typedef UINT16 histcell; /* histogram cell; prefer an unsigned type */
131 130
132 typedef histcell FAR * histptr;»/* for pointers to histogram cells */ 131 typedef histcell *histptr; /* for pointers to histogram cells */
133 132
134 typedef histcell hist1d[HIST_C2_ELEMS]; /* typedefs for the array */ 133 typedef histcell hist1d[HIST_C2_ELEMS]; /* typedefs for the array */
135 typedef hist1d FAR * hist2d;» /* type for the 2nd-level pointers */ 134 typedef hist1d *hist2d; /* type for the 2nd-level pointers */
136 typedef hist2d * hist3d;» /* type for top-level pointer */ 135 typedef hist2d *hist3d; /* type for top-level pointer */
137 136
138 137
139 /* Declarations for Floyd-Steinberg dithering. 138 /* Declarations for Floyd-Steinberg dithering.
140 * 139 *
141 * Errors are accumulated into the array fserrors[], at a resolution of 140 * Errors are accumulated into the array fserrors[], at a resolution of
142 * 1/16th of a pixel count. The error at a given pixel is propagated 141 * 1/16th of a pixel count. The error at a given pixel is propagated
143 * to its not-yet-processed neighbors using the standard F-S fractions, 142 * to its not-yet-processed neighbors using the standard F-S fractions,
144 *» » ...» (here)» 7/16 143 * ... (here) 7/16
145 *» » 3/16» 5/16» 1/16 144 * 3/16 5/16 1/16
146 * We work left-to-right on even rows, right-to-left on odd rows. 145 * We work left-to-right on even rows, right-to-left on odd rows.
147 * 146 *
148 * We can get away with a single array (holding one row's worth of errors) 147 * We can get away with a single array (holding one row's worth of errors)
149 * by using it to store the current row's errors at pixel columns not yet 148 * by using it to store the current row's errors at pixel columns not yet
150 * processed, but the next row's errors at columns already processed. We 149 * processed, but the next row's errors at columns already processed. We
151 * need only a few extra variables to hold the errors immediately around the 150 * need only a few extra variables to hold the errors immediately around the
152 * current column. (If we are lucky, those variables are in registers, but 151 * current column. (If we are lucky, those variables are in registers, but
153 * even if not, they're probably cheaper to access than array elements are.) 152 * even if not, they're probably cheaper to access than array elements are.)
154 * 153 *
155 * The fserrors[] array has (#columns + 2) entries; the extra entry at 154 * The fserrors[] array has (#columns + 2) entries; the extra entry at
156 * each end saves us from special-casing the first and last pixels. 155 * each end saves us from special-casing the first and last pixels.
157 * Each entry is three values long, one value for each color component. 156 * Each entry is three values long, one value for each color component.
158 *
159 * Note: on a wide image, we might not have enough room in a PC's near data
160 * segment to hold the error array; so it is allocated with alloc_large.
161 */ 157 */
162 158
163 #if BITS_IN_JSAMPLE == 8 159 #if BITS_IN_JSAMPLE == 8
164 typedef INT16 FSERROR;» » /* 16 bits should be enough */ 160 typedef INT16 FSERROR; /* 16 bits should be enough */
165 typedef int LOCFSERROR;»» /* use 'int' for calculation temps */ 161 typedef int LOCFSERROR; /* use 'int' for calculation temps */
166 #else 162 #else
167 typedef INT32 FSERROR;» » /* may need more than 16 bits */ 163 typedef JLONG FSERROR; /* may need more than 16 bits */
168 typedef INT32 LOCFSERROR;» /* be sure calculation temps are big enough */ 164 typedef JLONG LOCFSERROR; /* be sure calculation temps are big enough */
169 #endif 165 #endif
170 166
171 typedef FSERROR FAR *FSERRPTR;» /* pointer to error array (in FAR storage!) */ 167 typedef FSERROR *FSERRPTR; /* pointer to error array */
172 168
173 169
174 /* Private subobject */ 170 /* Private subobject */
175 171
176 typedef struct { 172 typedef struct {
177 struct jpeg_color_quantizer pub; /* public fields */ 173 struct jpeg_color_quantizer pub; /* public fields */
178 174
179 /* Space for the eventually created colormap is stashed here */ 175 /* Space for the eventually created colormap is stashed here */
180 JSAMPARRAY sv_colormap;» /* colormap allocated at init time */ 176 JSAMPARRAY sv_colormap; /* colormap allocated at init time */
181 int desired;» » » /* desired # of colors = size of colormap */ 177 int desired; /* desired # of colors = size of colormap */
182 178
183 /* Variables for accumulating image statistics */ 179 /* Variables for accumulating image statistics */
184 hist3d histogram;» » /* pointer to the histogram */ 180 hist3d histogram; /* pointer to the histogram */
185 181
186 boolean needs_zeroed;»» /* TRUE if next pass must zero histogram */ 182 boolean needs_zeroed; /* TRUE if next pass must zero histogram */
187 183
188 /* Variables for Floyd-Steinberg dithering */ 184 /* Variables for Floyd-Steinberg dithering */
189 FSERRPTR fserrors;» » /* accumulated errors */ 185 FSERRPTR fserrors; /* accumulated errors */
190 boolean on_odd_row;» » /* flag to remember which row we are on */ 186 boolean on_odd_row; /* flag to remember which row we are on */
191 int * error_limiter;» » /* table for clamping the applied error */ 187 int *error_limiter; /* table for clamping the applied error */
192 } my_cquantizer; 188 } my_cquantizer;
193 189
194 typedef my_cquantizer * my_cquantize_ptr; 190 typedef my_cquantizer *my_cquantize_ptr;
195 191
196 192
197 /* 193 /*
198 * Prescan some rows of pixels. 194 * Prescan some rows of pixels.
199 * In this module the prescan simply updates the histogram, which has been 195 * In this module the prescan simply updates the histogram, which has been
200 * initialized to zeroes by start_pass. 196 * initialized to zeroes by start_pass.
201 * An output_buf parameter is required by the method signature, but no data 197 * An output_buf parameter is required by the method signature, but no data
202 * is actually output (in fact the buffer controller is probably passing a 198 * is actually output (in fact the buffer controller is probably passing a
203 * NULL pointer). 199 * NULL pointer).
204 */ 200 */
205 201
206 METHODDEF(void) 202 METHODDEF(void)
207 prescan_quantize (j_decompress_ptr cinfo, JSAMPARRAY input_buf, 203 prescan_quantize (j_decompress_ptr cinfo, JSAMPARRAY input_buf,
208 » » JSAMPARRAY output_buf, int num_rows) 204 JSAMPARRAY output_buf, int num_rows)
209 { 205 {
210 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; 206 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;
211 register JSAMPROW ptr; 207 register JSAMPROW ptr;
212 register histptr histp; 208 register histptr histp;
213 register hist3d histogram = cquantize->histogram; 209 register hist3d histogram = cquantize->histogram;
214 int row; 210 int row;
215 JDIMENSION col; 211 JDIMENSION col;
216 JDIMENSION width = cinfo->output_width; 212 JDIMENSION width = cinfo->output_width;
217 213
218 for (row = 0; row < num_rows; row++) { 214 for (row = 0; row < num_rows; row++) {
219 ptr = input_buf[row]; 215 ptr = input_buf[row];
220 for (col = width; col > 0; col--) { 216 for (col = width; col > 0; col--) {
221 /* get pixel value and index into the histogram */ 217 /* get pixel value and index into the histogram */
222 histp = & histogram[GETJSAMPLE(ptr[0]) >> C0_SHIFT] 218 histp = & histogram[GETJSAMPLE(ptr[0]) >> C0_SHIFT]
223 » » » [GETJSAMPLE(ptr[1]) >> C1_SHIFT] 219 [GETJSAMPLE(ptr[1]) >> C1_SHIFT]
224 » » » [GETJSAMPLE(ptr[2]) >> C2_SHIFT]; 220 [GETJSAMPLE(ptr[2]) >> C2_SHIFT];
225 /* increment, check for overflow and undo increment if so. */ 221 /* increment, check for overflow and undo increment if so. */
226 if (++(*histp) <= 0) 222 if (++(*histp) <= 0)
227 » (*histp)--; 223 (*histp)--;
228 ptr += 3; 224 ptr += 3;
229 } 225 }
230 } 226 }
231 } 227 }
232 228
233 229
234 /* 230 /*
235 * Next we have the really interesting routines: selection of a colormap 231 * Next we have the really interesting routines: selection of a colormap
236 * given the completed histogram. 232 * given the completed histogram.
237 * These routines work with a list of "boxes", each representing a rectangular 233 * These routines work with a list of "boxes", each representing a rectangular
238 * subset of the input color space (to histogram precision). 234 * subset of the input color space (to histogram precision).
239 */ 235 */
240 236
241 typedef struct { 237 typedef struct {
242 /* The bounds of the box (inclusive); expressed as histogram indexes */ 238 /* The bounds of the box (inclusive); expressed as histogram indexes */
243 int c0min, c0max; 239 int c0min, c0max;
244 int c1min, c1max; 240 int c1min, c1max;
245 int c2min, c2max; 241 int c2min, c2max;
246 /* The volume (actually 2-norm) of the box */ 242 /* The volume (actually 2-norm) of the box */
247 INT32 volume; 243 JLONG volume;
248 /* The number of nonzero histogram cells within this box */ 244 /* The number of nonzero histogram cells within this box */
249 long colorcount; 245 long colorcount;
250 } box; 246 } box;
251 247
252 typedef box * boxptr; 248 typedef box *boxptr;
253 249
254 250
255 LOCAL(boxptr) 251 LOCAL(boxptr)
256 find_biggest_color_pop (boxptr boxlist, int numboxes) 252 find_biggest_color_pop (boxptr boxlist, int numboxes)
257 /* Find the splittable box with the largest color population */ 253 /* Find the splittable box with the largest color population */
258 /* Returns NULL if no splittable boxes remain */ 254 /* Returns NULL if no splittable boxes remain */
259 { 255 {
260 register boxptr boxp; 256 register boxptr boxp;
261 register int i; 257 register int i;
262 register long maxc = 0; 258 register long maxc = 0;
263 boxptr which = NULL; 259 boxptr which = NULL;
264 260
265 for (i = 0, boxp = boxlist; i < numboxes; i++, boxp++) { 261 for (i = 0, boxp = boxlist; i < numboxes; i++, boxp++) {
266 if (boxp->colorcount > maxc && boxp->volume > 0) { 262 if (boxp->colorcount > maxc && boxp->volume > 0) {
267 which = boxp; 263 which = boxp;
268 maxc = boxp->colorcount; 264 maxc = boxp->colorcount;
269 } 265 }
270 } 266 }
271 return which; 267 return which;
272 } 268 }
273 269
274 270
275 LOCAL(boxptr) 271 LOCAL(boxptr)
276 find_biggest_volume (boxptr boxlist, int numboxes) 272 find_biggest_volume (boxptr boxlist, int numboxes)
277 /* Find the splittable box with the largest (scaled) volume */ 273 /* Find the splittable box with the largest (scaled) volume */
278 /* Returns NULL if no splittable boxes remain */ 274 /* Returns NULL if no splittable boxes remain */
279 { 275 {
280 register boxptr boxp; 276 register boxptr boxp;
281 register int i; 277 register int i;
282 register INT32 maxv = 0; 278 register JLONG maxv = 0;
283 boxptr which = NULL; 279 boxptr which = NULL;
284 280
285 for (i = 0, boxp = boxlist; i < numboxes; i++, boxp++) { 281 for (i = 0, boxp = boxlist; i < numboxes; i++, boxp++) {
286 if (boxp->volume > maxv) { 282 if (boxp->volume > maxv) {
287 which = boxp; 283 which = boxp;
288 maxv = boxp->volume; 284 maxv = boxp->volume;
289 } 285 }
290 } 286 }
291 return which; 287 return which;
292 } 288 }
293 289
294 290
295 LOCAL(void) 291 LOCAL(void)
296 update_box (j_decompress_ptr cinfo, boxptr boxp) 292 update_box (j_decompress_ptr cinfo, boxptr boxp)
297 /* Shrink the min/max bounds of a box to enclose only nonzero elements, */ 293 /* Shrink the min/max bounds of a box to enclose only nonzero elements, */
298 /* and recompute its volume and population */ 294 /* and recompute its volume and population */
299 { 295 {
300 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; 296 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;
301 hist3d histogram = cquantize->histogram; 297 hist3d histogram = cquantize->histogram;
302 histptr histp; 298 histptr histp;
303 int c0,c1,c2; 299 int c0,c1,c2;
304 int c0min,c0max,c1min,c1max,c2min,c2max; 300 int c0min,c0max,c1min,c1max,c2min,c2max;
305 INT32 dist0,dist1,dist2; 301 JLONG dist0,dist1,dist2;
306 long ccount; 302 long ccount;
307 303
308 c0min = boxp->c0min; c0max = boxp->c0max; 304 c0min = boxp->c0min; c0max = boxp->c0max;
309 c1min = boxp->c1min; c1max = boxp->c1max; 305 c1min = boxp->c1min; c1max = boxp->c1max;
310 c2min = boxp->c2min; c2max = boxp->c2max; 306 c2min = boxp->c2min; c2max = boxp->c2max;
311 307
312 if (c0max > c0min) 308 if (c0max > c0min)
313 for (c0 = c0min; c0 <= c0max; c0++) 309 for (c0 = c0min; c0 <= c0max; c0++)
314 for (c1 = c1min; c1 <= c1max; c1++) { 310 for (c1 = c1min; c1 <= c1max; c1++) {
315 » histp = & histogram[c0][c1][c2min]; 311 histp = & histogram[c0][c1][c2min];
316 » for (c2 = c2min; c2 <= c2max; c2++) 312 for (c2 = c2min; c2 <= c2max; c2++)
317 » if (*histp++ != 0) { 313 if (*histp++ != 0) {
318 » boxp->c0min = c0min = c0; 314 boxp->c0min = c0min = c0;
319 » goto have_c0min; 315 goto have_c0min;
320 » } 316 }
321 } 317 }
322 have_c0min: 318 have_c0min:
323 if (c0max > c0min) 319 if (c0max > c0min)
324 for (c0 = c0max; c0 >= c0min; c0--) 320 for (c0 = c0max; c0 >= c0min; c0--)
325 for (c1 = c1min; c1 <= c1max; c1++) { 321 for (c1 = c1min; c1 <= c1max; c1++) {
326 » histp = & histogram[c0][c1][c2min]; 322 histp = & histogram[c0][c1][c2min];
327 » for (c2 = c2min; c2 <= c2max; c2++) 323 for (c2 = c2min; c2 <= c2max; c2++)
328 » if (*histp++ != 0) { 324 if (*histp++ != 0) {
329 » boxp->c0max = c0max = c0; 325 boxp->c0max = c0max = c0;
330 » goto have_c0max; 326 goto have_c0max;
331 » } 327 }
332 } 328 }
333 have_c0max: 329 have_c0max:
334 if (c1max > c1min) 330 if (c1max > c1min)
335 for (c1 = c1min; c1 <= c1max; c1++) 331 for (c1 = c1min; c1 <= c1max; c1++)
336 for (c0 = c0min; c0 <= c0max; c0++) { 332 for (c0 = c0min; c0 <= c0max; c0++) {
337 » histp = & histogram[c0][c1][c2min]; 333 histp = & histogram[c0][c1][c2min];
338 » for (c2 = c2min; c2 <= c2max; c2++) 334 for (c2 = c2min; c2 <= c2max; c2++)
339 » if (*histp++ != 0) { 335 if (*histp++ != 0) {
340 » boxp->c1min = c1min = c1; 336 boxp->c1min = c1min = c1;
341 » goto have_c1min; 337 goto have_c1min;
342 » } 338 }
343 } 339 }
344 have_c1min: 340 have_c1min:
345 if (c1max > c1min) 341 if (c1max > c1min)
346 for (c1 = c1max; c1 >= c1min; c1--) 342 for (c1 = c1max; c1 >= c1min; c1--)
347 for (c0 = c0min; c0 <= c0max; c0++) { 343 for (c0 = c0min; c0 <= c0max; c0++) {
348 » histp = & histogram[c0][c1][c2min]; 344 histp = & histogram[c0][c1][c2min];
349 » for (c2 = c2min; c2 <= c2max; c2++) 345 for (c2 = c2min; c2 <= c2max; c2++)
350 » if (*histp++ != 0) { 346 if (*histp++ != 0) {
351 » boxp->c1max = c1max = c1; 347 boxp->c1max = c1max = c1;
352 » goto have_c1max; 348 goto have_c1max;
353 » } 349 }
354 } 350 }
355 have_c1max: 351 have_c1max:
356 if (c2max > c2min) 352 if (c2max > c2min)
357 for (c2 = c2min; c2 <= c2max; c2++) 353 for (c2 = c2min; c2 <= c2max; c2++)
358 for (c0 = c0min; c0 <= c0max; c0++) { 354 for (c0 = c0min; c0 <= c0max; c0++) {
359 » histp = & histogram[c0][c1min][c2]; 355 histp = & histogram[c0][c1min][c2];
360 » for (c1 = c1min; c1 <= c1max; c1++, histp += HIST_C2_ELEMS) 356 for (c1 = c1min; c1 <= c1max; c1++, histp += HIST_C2_ELEMS)
361 » if (*histp != 0) { 357 if (*histp != 0) {
362 » boxp->c2min = c2min = c2; 358 boxp->c2min = c2min = c2;
363 » goto have_c2min; 359 goto have_c2min;
364 » } 360 }
365 } 361 }
366 have_c2min: 362 have_c2min:
367 if (c2max > c2min) 363 if (c2max > c2min)
368 for (c2 = c2max; c2 >= c2min; c2--) 364 for (c2 = c2max; c2 >= c2min; c2--)
369 for (c0 = c0min; c0 <= c0max; c0++) { 365 for (c0 = c0min; c0 <= c0max; c0++) {
370 » histp = & histogram[c0][c1min][c2]; 366 histp = & histogram[c0][c1min][c2];
371 » for (c1 = c1min; c1 <= c1max; c1++, histp += HIST_C2_ELEMS) 367 for (c1 = c1min; c1 <= c1max; c1++, histp += HIST_C2_ELEMS)
372 » if (*histp != 0) { 368 if (*histp != 0) {
373 » boxp->c2max = c2max = c2; 369 boxp->c2max = c2max = c2;
374 » goto have_c2max; 370 goto have_c2max;
375 » } 371 }
376 } 372 }
377 have_c2max: 373 have_c2max:
378 374
379 /* Update box volume. 375 /* Update box volume.
380 * We use 2-norm rather than real volume here; this biases the method 376 * We use 2-norm rather than real volume here; this biases the method
381 * against making long narrow boxes, and it has the side benefit that 377 * against making long narrow boxes, and it has the side benefit that
382 * a box is splittable iff norm > 0. 378 * a box is splittable iff norm > 0.
383 * Since the differences are expressed in histogram-cell units, 379 * Since the differences are expressed in histogram-cell units,
384 * we have to shift back to JSAMPLE units to get consistent distances; 380 * we have to shift back to JSAMPLE units to get consistent distances;
385 * after which, we scale according to the selected distance scale factors. 381 * after which, we scale according to the selected distance scale factors.
386 */ 382 */
387 dist0 = ((c0max - c0min) << C0_SHIFT) * C0_SCALE; 383 dist0 = ((c0max - c0min) << C0_SHIFT) * C0_SCALE;
388 dist1 = ((c1max - c1min) << C1_SHIFT) * C1_SCALE; 384 dist1 = ((c1max - c1min) << C1_SHIFT) * C1_SCALE;
389 dist2 = ((c2max - c2min) << C2_SHIFT) * C2_SCALE; 385 dist2 = ((c2max - c2min) << C2_SHIFT) * C2_SCALE;
390 boxp->volume = dist0*dist0 + dist1*dist1 + dist2*dist2; 386 boxp->volume = dist0*dist0 + dist1*dist1 + dist2*dist2;
391 387
392 /* Now scan remaining volume of box and compute population */ 388 /* Now scan remaining volume of box and compute population */
393 ccount = 0; 389 ccount = 0;
394 for (c0 = c0min; c0 <= c0max; c0++) 390 for (c0 = c0min; c0 <= c0max; c0++)
395 for (c1 = c1min; c1 <= c1max; c1++) { 391 for (c1 = c1min; c1 <= c1max; c1++) {
396 histp = & histogram[c0][c1][c2min]; 392 histp = & histogram[c0][c1][c2min];
397 for (c2 = c2min; c2 <= c2max; c2++, histp++) 393 for (c2 = c2min; c2 <= c2max; c2++, histp++)
398 » if (*histp != 0) { 394 if (*histp != 0) {
399 » ccount++; 395 ccount++;
400 » } 396 }
401 } 397 }
402 boxp->colorcount = ccount; 398 boxp->colorcount = ccount;
403 } 399 }
404 400
405 401
406 LOCAL(int) 402 LOCAL(int)
407 median_cut (j_decompress_ptr cinfo, boxptr boxlist, int numboxes, 403 median_cut (j_decompress_ptr cinfo, boxptr boxlist, int numboxes,
408 » int desired_colors) 404 int desired_colors)
409 /* Repeatedly select and split the largest box until we have enough boxes */ 405 /* Repeatedly select and split the largest box until we have enough boxes */
410 { 406 {
411 int n,lb; 407 int n,lb;
412 int c0,c1,c2,cmax; 408 int c0,c1,c2,cmax;
413 register boxptr b1,b2; 409 register boxptr b1,b2;
414 410
415 while (numboxes < desired_colors) { 411 while (numboxes < desired_colors) {
416 /* Select box to split. 412 /* Select box to split.
417 * Current algorithm: by population for first half, then by volume. 413 * Current algorithm: by population for first half, then by volume.
418 */ 414 */
419 if (numboxes*2 <= desired_colors) { 415 if (numboxes*2 <= desired_colors) {
420 b1 = find_biggest_color_pop(boxlist, numboxes); 416 b1 = find_biggest_color_pop(boxlist, numboxes);
421 } else { 417 } else {
422 b1 = find_biggest_volume(boxlist, numboxes); 418 b1 = find_biggest_volume(boxlist, numboxes);
423 } 419 }
424 if (b1 == NULL)» » /* no splittable boxes left! */ 420 if (b1 == NULL) /* no splittable boxes left! */
425 break; 421 break;
426 b2 = &boxlist[numboxes];» /* where new box will go */ 422 b2 = &boxlist[numboxes]; /* where new box will go */
427 /* Copy the color bounds to the new box. */ 423 /* Copy the color bounds to the new box. */
428 b2->c0max = b1->c0max; b2->c1max = b1->c1max; b2->c2max = b1->c2max; 424 b2->c0max = b1->c0max; b2->c1max = b1->c1max; b2->c2max = b1->c2max;
429 b2->c0min = b1->c0min; b2->c1min = b1->c1min; b2->c2min = b1->c2min; 425 b2->c0min = b1->c0min; b2->c1min = b1->c1min; b2->c2min = b1->c2min;
430 /* Choose which axis to split the box on. 426 /* Choose which axis to split the box on.
431 * Current algorithm: longest scaled axis. 427 * Current algorithm: longest scaled axis.
432 * See notes in update_box about scaling distances. 428 * See notes in update_box about scaling distances.
433 */ 429 */
434 c0 = ((b1->c0max - b1->c0min) << C0_SHIFT) * C0_SCALE; 430 c0 = ((b1->c0max - b1->c0min) << C0_SHIFT) * C0_SCALE;
435 c1 = ((b1->c1max - b1->c1min) << C1_SHIFT) * C1_SCALE; 431 c1 = ((b1->c1max - b1->c1min) << C1_SHIFT) * C1_SCALE;
436 c2 = ((b1->c2max - b1->c2min) << C2_SHIFT) * C2_SCALE; 432 c2 = ((b1->c2max - b1->c2min) << C2_SHIFT) * C2_SCALE;
(...skipping 51 matching lines...) Expand 10 before | Expand all | Expand 10 after
488 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; 484 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;
489 hist3d histogram = cquantize->histogram; 485 hist3d histogram = cquantize->histogram;
490 histptr histp; 486 histptr histp;
491 int c0,c1,c2; 487 int c0,c1,c2;
492 int c0min,c0max,c1min,c1max,c2min,c2max; 488 int c0min,c0max,c1min,c1max,c2min,c2max;
493 long count; 489 long count;
494 long total = 0; 490 long total = 0;
495 long c0total = 0; 491 long c0total = 0;
496 long c1total = 0; 492 long c1total = 0;
497 long c2total = 0; 493 long c2total = 0;
498 494
499 c0min = boxp->c0min; c0max = boxp->c0max; 495 c0min = boxp->c0min; c0max = boxp->c0max;
500 c1min = boxp->c1min; c1max = boxp->c1max; 496 c1min = boxp->c1min; c1max = boxp->c1max;
501 c2min = boxp->c2min; c2max = boxp->c2max; 497 c2min = boxp->c2min; c2max = boxp->c2max;
502 498
503 for (c0 = c0min; c0 <= c0max; c0++) 499 for (c0 = c0min; c0 <= c0max; c0++)
504 for (c1 = c1min; c1 <= c1max; c1++) { 500 for (c1 = c1min; c1 <= c1max; c1++) {
505 histp = & histogram[c0][c1][c2min]; 501 histp = & histogram[c0][c1][c2min];
506 for (c2 = c2min; c2 <= c2max; c2++) { 502 for (c2 = c2min; c2 <= c2max; c2++) {
507 » if ((count = *histp++) != 0) { 503 if ((count = *histp++) != 0) {
508 » total += count; 504 total += count;
509 » c0total += ((c0 << C0_SHIFT) + ((1<<C0_SHIFT)>>1)) * count; 505 c0total += ((c0 << C0_SHIFT) + ((1<<C0_SHIFT)>>1)) * count;
510 » c1total += ((c1 << C1_SHIFT) + ((1<<C1_SHIFT)>>1)) * count; 506 c1total += ((c1 << C1_SHIFT) + ((1<<C1_SHIFT)>>1)) * count;
511 » c2total += ((c2 << C2_SHIFT) + ((1<<C2_SHIFT)>>1)) * count; 507 c2total += ((c2 << C2_SHIFT) + ((1<<C2_SHIFT)>>1)) * count;
512 » } 508 }
513 } 509 }
514 } 510 }
515 511
516 cinfo->colormap[0][icolor] = (JSAMPLE) ((c0total + (total>>1)) / total); 512 cinfo->colormap[0][icolor] = (JSAMPLE) ((c0total + (total>>1)) / total);
517 cinfo->colormap[1][icolor] = (JSAMPLE) ((c1total + (total>>1)) / total); 513 cinfo->colormap[1][icolor] = (JSAMPLE) ((c1total + (total>>1)) / total);
518 cinfo->colormap[2][icolor] = (JSAMPLE) ((c2total + (total>>1)) / total); 514 cinfo->colormap[2][icolor] = (JSAMPLE) ((c2total + (total>>1)) / total);
519 } 515 }
520 516
521 517
522 LOCAL(void) 518 LOCAL(void)
523 select_colors (j_decompress_ptr cinfo, int desired_colors) 519 select_colors (j_decompress_ptr cinfo, int desired_colors)
524 /* Master routine for color selection */ 520 /* Master routine for color selection */
525 { 521 {
526 boxptr boxlist; 522 boxptr boxlist;
527 int numboxes; 523 int numboxes;
528 int i; 524 int i;
529 525
530 /* Allocate workspace for box list */ 526 /* Allocate workspace for box list */
531 boxlist = (boxptr) (*cinfo->mem->alloc_small) 527 boxlist = (boxptr) (*cinfo->mem->alloc_small)
532 ((j_common_ptr) cinfo, JPOOL_IMAGE, desired_colors * SIZEOF(box)); 528 ((j_common_ptr) cinfo, JPOOL_IMAGE, desired_colors * sizeof(box));
533 /* Initialize one box containing whole space */ 529 /* Initialize one box containing whole space */
534 numboxes = 1; 530 numboxes = 1;
535 boxlist[0].c0min = 0; 531 boxlist[0].c0min = 0;
536 boxlist[0].c0max = MAXJSAMPLE >> C0_SHIFT; 532 boxlist[0].c0max = MAXJSAMPLE >> C0_SHIFT;
537 boxlist[0].c1min = 0; 533 boxlist[0].c1min = 0;
538 boxlist[0].c1max = MAXJSAMPLE >> C1_SHIFT; 534 boxlist[0].c1max = MAXJSAMPLE >> C1_SHIFT;
539 boxlist[0].c2min = 0; 535 boxlist[0].c2min = 0;
540 boxlist[0].c2max = MAXJSAMPLE >> C2_SHIFT; 536 boxlist[0].c2max = MAXJSAMPLE >> C2_SHIFT;
541 /* Shrink it to actually-used volume and set its statistics */ 537 /* Shrink it to actually-used volume and set its statistics */
542 update_box(cinfo, & boxlist[0]); 538 update_box(cinfo, & boxlist[0]);
(...skipping 26 matching lines...) Expand all
569 * sorted search" idea described by Heckbert and on the incremental distance 565 * sorted search" idea described by Heckbert and on the incremental distance
570 * calculation described by Spencer W. Thomas in chapter III.1 of Graphics 566 * calculation described by Spencer W. Thomas in chapter III.1 of Graphics
571 * Gems II (James Arvo, ed. Academic Press, 1991). Thomas points out that 567 * Gems II (James Arvo, ed. Academic Press, 1991). Thomas points out that
572 * the distances from a given colormap entry to each cell of the histogram can 568 * the distances from a given colormap entry to each cell of the histogram can
573 * be computed quickly using an incremental method: the differences between 569 * be computed quickly using an incremental method: the differences between
574 * distances to adjacent cells themselves differ by a constant. This allows a 570 * distances to adjacent cells themselves differ by a constant. This allows a
575 * fairly fast implementation of the "brute force" approach of computing the 571 * fairly fast implementation of the "brute force" approach of computing the
576 * distance from every colormap entry to every histogram cell. Unfortunately, 572 * distance from every colormap entry to every histogram cell. Unfortunately,
577 * it needs a work array to hold the best-distance-so-far for each histogram 573 * it needs a work array to hold the best-distance-so-far for each histogram
578 * cell (because the inner loop has to be over cells, not colormap entries). 574 * cell (because the inner loop has to be over cells, not colormap entries).
579 * The work array elements have to be INT32s, so the work array would need 575 * The work array elements have to be JLONGs, so the work array would need
580 * 256Kb at our recommended precision. This is not feasible in DOS machines. 576 * 256Kb at our recommended precision. This is not feasible in DOS machines.
581 * 577 *
582 * To get around these problems, we apply Thomas' method to compute the 578 * To get around these problems, we apply Thomas' method to compute the
583 * nearest colors for only the cells within a small subbox of the histogram. 579 * nearest colors for only the cells within a small subbox of the histogram.
584 * The work array need be only as big as the subbox, so the memory usage 580 * The work array need be only as big as the subbox, so the memory usage
585 * problem is solved. Furthermore, we need not fill subboxes that are never 581 * problem is solved. Furthermore, we need not fill subboxes that are never
586 * referenced in pass2; many images use only part of the color gamut, so a 582 * referenced in pass2; many images use only part of the color gamut, so a
587 * fair amount of work is saved. An additional advantage of this 583 * fair amount of work is saved. An additional advantage of this
588 * approach is that we can apply Heckbert's locality criterion to quickly 584 * approach is that we can apply Heckbert's locality criterion to quickly
589 * eliminate colormap entries that are far away from the subbox; typically 585 * eliminate colormap entries that are far away from the subbox; typically
(...skipping 31 matching lines...) Expand 10 before | Expand all | Expand 10 after
621 /* 617 /*
622 * The next three routines implement inverse colormap filling. They could 618 * The next three routines implement inverse colormap filling. They could
623 * all be folded into one big routine, but splitting them up this way saves 619 * all be folded into one big routine, but splitting them up this way saves
624 * some stack space (the mindist[] and bestdist[] arrays need not coexist) 620 * some stack space (the mindist[] and bestdist[] arrays need not coexist)
625 * and may allow some compilers to produce better code by registerizing more 621 * and may allow some compilers to produce better code by registerizing more
626 * inner-loop variables. 622 * inner-loop variables.
627 */ 623 */
628 624
629 LOCAL(int) 625 LOCAL(int)
630 find_nearby_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2, 626 find_nearby_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2,
631 » » JSAMPLE colorlist[]) 627 JSAMPLE colorlist[])
632 /* Locate the colormap entries close enough to an update box to be candidates 628 /* Locate the colormap entries close enough to an update box to be candidates
633 * for the nearest entry to some cell(s) in the update box. The update box 629 * for the nearest entry to some cell(s) in the update box. The update box
634 * is specified by the center coordinates of its first cell. The number of 630 * is specified by the center coordinates of its first cell. The number of
635 * candidate colormap entries is returned, and their colormap indexes are 631 * candidate colormap entries is returned, and their colormap indexes are
636 * placed in colorlist[]. 632 * placed in colorlist[].
637 * This routine uses Heckbert's "locally sorted search" criterion to select 633 * This routine uses Heckbert's "locally sorted search" criterion to select
638 * the colors that need further consideration. 634 * the colors that need further consideration.
639 */ 635 */
640 { 636 {
641 int numcolors = cinfo->actual_number_of_colors; 637 int numcolors = cinfo->actual_number_of_colors;
642 int maxc0, maxc1, maxc2; 638 int maxc0, maxc1, maxc2;
643 int centerc0, centerc1, centerc2; 639 int centerc0, centerc1, centerc2;
644 int i, x, ncolors; 640 int i, x, ncolors;
645 INT32 minmaxdist, min_dist, max_dist, tdist; 641 JLONG minmaxdist, min_dist, max_dist, tdist;
646 INT32 mindist[MAXNUMCOLORS];» /* min distance to colormap entry i */ 642 JLONG mindist[MAXNUMCOLORS]; /* min distance to colormap entry i */
647 643
648 /* Compute true coordinates of update box's upper corner and center. 644 /* Compute true coordinates of update box's upper corner and center.
649 * Actually we compute the coordinates of the center of the upper-corner 645 * Actually we compute the coordinates of the center of the upper-corner
650 * histogram cell, which are the upper bounds of the volume we care about. 646 * histogram cell, which are the upper bounds of the volume we care about.
651 * Note that since ">>" rounds down, the "center" values may be closer to 647 * Note that since ">>" rounds down, the "center" values may be closer to
652 * min than to max; hence comparisons to them must be "<=", not "<". 648 * min than to max; hence comparisons to them must be "<=", not "<".
653 */ 649 */
654 maxc0 = minc0 + ((1 << BOX_C0_SHIFT) - (1 << C0_SHIFT)); 650 maxc0 = minc0 + ((1 << BOX_C0_SHIFT) - (1 << C0_SHIFT));
655 centerc0 = (minc0 + maxc0) >> 1; 651 centerc0 = (minc0 + maxc0) >> 1;
656 maxc1 = minc1 + ((1 << BOX_C1_SHIFT) - (1 << C1_SHIFT)); 652 maxc1 = minc1 + ((1 << BOX_C1_SHIFT) - (1 << C1_SHIFT));
(...skipping 21 matching lines...) Expand all
678 max_dist = tdist*tdist; 674 max_dist = tdist*tdist;
679 } else if (x > maxc0) { 675 } else if (x > maxc0) {
680 tdist = (x - maxc0) * C0_SCALE; 676 tdist = (x - maxc0) * C0_SCALE;
681 min_dist = tdist*tdist; 677 min_dist = tdist*tdist;
682 tdist = (x - minc0) * C0_SCALE; 678 tdist = (x - minc0) * C0_SCALE;
683 max_dist = tdist*tdist; 679 max_dist = tdist*tdist;
684 } else { 680 } else {
685 /* within cell range so no contribution to min_dist */ 681 /* within cell range so no contribution to min_dist */
686 min_dist = 0; 682 min_dist = 0;
687 if (x <= centerc0) { 683 if (x <= centerc0) {
688 » tdist = (x - maxc0) * C0_SCALE; 684 tdist = (x - maxc0) * C0_SCALE;
689 » max_dist = tdist*tdist; 685 max_dist = tdist*tdist;
690 } else { 686 } else {
691 » tdist = (x - minc0) * C0_SCALE; 687 tdist = (x - minc0) * C0_SCALE;
692 » max_dist = tdist*tdist; 688 max_dist = tdist*tdist;
693 } 689 }
694 } 690 }
695 691
696 x = GETJSAMPLE(cinfo->colormap[1][i]); 692 x = GETJSAMPLE(cinfo->colormap[1][i]);
697 if (x < minc1) { 693 if (x < minc1) {
698 tdist = (x - minc1) * C1_SCALE; 694 tdist = (x - minc1) * C1_SCALE;
699 min_dist += tdist*tdist; 695 min_dist += tdist*tdist;
700 tdist = (x - maxc1) * C1_SCALE; 696 tdist = (x - maxc1) * C1_SCALE;
701 max_dist += tdist*tdist; 697 max_dist += tdist*tdist;
702 } else if (x > maxc1) { 698 } else if (x > maxc1) {
703 tdist = (x - maxc1) * C1_SCALE; 699 tdist = (x - maxc1) * C1_SCALE;
704 min_dist += tdist*tdist; 700 min_dist += tdist*tdist;
705 tdist = (x - minc1) * C1_SCALE; 701 tdist = (x - minc1) * C1_SCALE;
706 max_dist += tdist*tdist; 702 max_dist += tdist*tdist;
707 } else { 703 } else {
708 /* within cell range so no contribution to min_dist */ 704 /* within cell range so no contribution to min_dist */
709 if (x <= centerc1) { 705 if (x <= centerc1) {
710 » tdist = (x - maxc1) * C1_SCALE; 706 tdist = (x - maxc1) * C1_SCALE;
711 » max_dist += tdist*tdist; 707 max_dist += tdist*tdist;
712 } else { 708 } else {
713 » tdist = (x - minc1) * C1_SCALE; 709 tdist = (x - minc1) * C1_SCALE;
714 » max_dist += tdist*tdist; 710 max_dist += tdist*tdist;
715 } 711 }
716 } 712 }
717 713
718 x = GETJSAMPLE(cinfo->colormap[2][i]); 714 x = GETJSAMPLE(cinfo->colormap[2][i]);
719 if (x < minc2) { 715 if (x < minc2) {
720 tdist = (x - minc2) * C2_SCALE; 716 tdist = (x - minc2) * C2_SCALE;
721 min_dist += tdist*tdist; 717 min_dist += tdist*tdist;
722 tdist = (x - maxc2) * C2_SCALE; 718 tdist = (x - maxc2) * C2_SCALE;
723 max_dist += tdist*tdist; 719 max_dist += tdist*tdist;
724 } else if (x > maxc2) { 720 } else if (x > maxc2) {
725 tdist = (x - maxc2) * C2_SCALE; 721 tdist = (x - maxc2) * C2_SCALE;
726 min_dist += tdist*tdist; 722 min_dist += tdist*tdist;
727 tdist = (x - minc2) * C2_SCALE; 723 tdist = (x - minc2) * C2_SCALE;
728 max_dist += tdist*tdist; 724 max_dist += tdist*tdist;
729 } else { 725 } else {
730 /* within cell range so no contribution to min_dist */ 726 /* within cell range so no contribution to min_dist */
731 if (x <= centerc2) { 727 if (x <= centerc2) {
732 » tdist = (x - maxc2) * C2_SCALE; 728 tdist = (x - maxc2) * C2_SCALE;
733 » max_dist += tdist*tdist; 729 max_dist += tdist*tdist;
734 } else { 730 } else {
735 » tdist = (x - minc2) * C2_SCALE; 731 tdist = (x - minc2) * C2_SCALE;
736 » max_dist += tdist*tdist; 732 max_dist += tdist*tdist;
737 } 733 }
738 } 734 }
739 735
740 mindist[i] = min_dist;» /* save away the results */ 736 mindist[i] = min_dist; /* save away the results */
741 if (max_dist < minmaxdist) 737 if (max_dist < minmaxdist)
742 minmaxdist = max_dist; 738 minmaxdist = max_dist;
743 } 739 }
744 740
745 /* Now we know that no cell in the update box is more than minmaxdist 741 /* Now we know that no cell in the update box is more than minmaxdist
746 * away from some colormap entry. Therefore, only colors that are 742 * away from some colormap entry. Therefore, only colors that are
747 * within minmaxdist of some part of the box need be considered. 743 * within minmaxdist of some part of the box need be considered.
748 */ 744 */
749 ncolors = 0; 745 ncolors = 0;
750 for (i = 0; i < numcolors; i++) { 746 for (i = 0; i < numcolors; i++) {
751 if (mindist[i] <= minmaxdist) 747 if (mindist[i] <= minmaxdist)
752 colorlist[ncolors++] = (JSAMPLE) i; 748 colorlist[ncolors++] = (JSAMPLE) i;
753 } 749 }
754 return ncolors; 750 return ncolors;
755 } 751 }
756 752
757 753
758 LOCAL(void) 754 LOCAL(void)
759 find_best_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2, 755 find_best_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2,
760 » » int numcolors, JSAMPLE colorlist[], JSAMPLE bestcolor[]) 756 int numcolors, JSAMPLE colorlist[], JSAMPLE bestcolor[])
761 /* Find the closest colormap entry for each cell in the update box, 757 /* Find the closest colormap entry for each cell in the update box,
762 * given the list of candidate colors prepared by find_nearby_colors. 758 * given the list of candidate colors prepared by find_nearby_colors.
763 * Return the indexes of the closest entries in the bestcolor[] array. 759 * Return the indexes of the closest entries in the bestcolor[] array.
764 * This routine uses Thomas' incremental distance calculation method to 760 * This routine uses Thomas' incremental distance calculation method to
765 * find the distance from a colormap entry to successive cells in the box. 761 * find the distance from a colormap entry to successive cells in the box.
766 */ 762 */
767 { 763 {
768 int ic0, ic1, ic2; 764 int ic0, ic1, ic2;
769 int i, icolor; 765 int i, icolor;
770 register INT32 * bptr;» /* pointer into bestdist[] array */ 766 register JLONG *bptr; /* pointer into bestdist[] array */
771 JSAMPLE * cptr;» » /* pointer into bestcolor[] array */ 767 JSAMPLE *cptr; /* pointer into bestcolor[] array */
772 INT32 dist0, dist1;» » /* initial distance values */ 768 JLONG dist0, dist1; /* initial distance values */
773 register INT32 dist2;»» /* current distance in inner loop */ 769 register JLONG dist2; /* current distance in inner loop */
774 INT32 xx0, xx1;» » /* distance increments */ 770 JLONG xx0, xx1; /* distance increments */
775 register INT32 xx2; 771 register JLONG xx2;
776 INT32 inc0, inc1, inc2;» /* initial values for increments */ 772 JLONG inc0, inc1, inc2; /* initial values for increments */
777 /* This array holds the distance to the nearest-so-far color for each cell */ 773 /* This array holds the distance to the nearest-so-far color for each cell */
778 INT32 bestdist[BOX_C0_ELEMS * BOX_C1_ELEMS * BOX_C2_ELEMS]; 774 JLONG bestdist[BOX_C0_ELEMS * BOX_C1_ELEMS * BOX_C2_ELEMS];
779 775
780 /* Initialize best-distance for each cell of the update box */ 776 /* Initialize best-distance for each cell of the update box */
781 bptr = bestdist; 777 bptr = bestdist;
782 for (i = BOX_C0_ELEMS*BOX_C1_ELEMS*BOX_C2_ELEMS-1; i >= 0; i--) 778 for (i = BOX_C0_ELEMS*BOX_C1_ELEMS*BOX_C2_ELEMS-1; i >= 0; i--)
783 *bptr++ = 0x7FFFFFFFL; 779 *bptr++ = 0x7FFFFFFFL;
784 780
785 /* For each color selected by find_nearby_colors, 781 /* For each color selected by find_nearby_colors,
786 * compute its distance to the center of each cell in the box. 782 * compute its distance to the center of each cell in the box.
787 * If that's less than best-so-far, update best distance and color number. 783 * If that's less than best-so-far, update best distance and color number.
788 */ 784 */
789 785
790 /* Nominal steps between cell centers ("x" in Thomas article) */ 786 /* Nominal steps between cell centers ("x" in Thomas article) */
791 #define STEP_C0 ((1 << C0_SHIFT) * C0_SCALE) 787 #define STEP_C0 ((1 << C0_SHIFT) * C0_SCALE)
792 #define STEP_C1 ((1 << C1_SHIFT) * C1_SCALE) 788 #define STEP_C1 ((1 << C1_SHIFT) * C1_SCALE)
793 #define STEP_C2 ((1 << C2_SHIFT) * C2_SCALE) 789 #define STEP_C2 ((1 << C2_SHIFT) * C2_SCALE)
794 790
795 for (i = 0; i < numcolors; i++) { 791 for (i = 0; i < numcolors; i++) {
796 icolor = GETJSAMPLE(colorlist[i]); 792 icolor = GETJSAMPLE(colorlist[i]);
797 /* Compute (square of) distance from minc0/c1/c2 to this color */ 793 /* Compute (square of) distance from minc0/c1/c2 to this color */
798 inc0 = (minc0 - GETJSAMPLE(cinfo->colormap[0][icolor])) * C0_SCALE; 794 inc0 = (minc0 - GETJSAMPLE(cinfo->colormap[0][icolor])) * C0_SCALE;
799 dist0 = inc0*inc0; 795 dist0 = inc0*inc0;
800 inc1 = (minc1 - GETJSAMPLE(cinfo->colormap[1][icolor])) * C1_SCALE; 796 inc1 = (minc1 - GETJSAMPLE(cinfo->colormap[1][icolor])) * C1_SCALE;
801 dist0 += inc1*inc1; 797 dist0 += inc1*inc1;
802 inc2 = (minc2 - GETJSAMPLE(cinfo->colormap[2][icolor])) * C2_SCALE; 798 inc2 = (minc2 - GETJSAMPLE(cinfo->colormap[2][icolor])) * C2_SCALE;
803 dist0 += inc2*inc2; 799 dist0 += inc2*inc2;
804 /* Form the initial difference increments */ 800 /* Form the initial difference increments */
805 inc0 = inc0 * (2 * STEP_C0) + STEP_C0 * STEP_C0; 801 inc0 = inc0 * (2 * STEP_C0) + STEP_C0 * STEP_C0;
806 inc1 = inc1 * (2 * STEP_C1) + STEP_C1 * STEP_C1; 802 inc1 = inc1 * (2 * STEP_C1) + STEP_C1 * STEP_C1;
807 inc2 = inc2 * (2 * STEP_C2) + STEP_C2 * STEP_C2; 803 inc2 = inc2 * (2 * STEP_C2) + STEP_C2 * STEP_C2;
808 /* Now loop over all cells in box, updating distance per Thomas method */ 804 /* Now loop over all cells in box, updating distance per Thomas method */
809 bptr = bestdist; 805 bptr = bestdist;
810 cptr = bestcolor; 806 cptr = bestcolor;
811 xx0 = inc0; 807 xx0 = inc0;
812 for (ic0 = BOX_C0_ELEMS-1; ic0 >= 0; ic0--) { 808 for (ic0 = BOX_C0_ELEMS-1; ic0 >= 0; ic0--) {
813 dist1 = dist0; 809 dist1 = dist0;
814 xx1 = inc1; 810 xx1 = inc1;
815 for (ic1 = BOX_C1_ELEMS-1; ic1 >= 0; ic1--) { 811 for (ic1 = BOX_C1_ELEMS-1; ic1 >= 0; ic1--) {
816 » dist2 = dist1; 812 dist2 = dist1;
817 » xx2 = inc2; 813 xx2 = inc2;
818 » for (ic2 = BOX_C2_ELEMS-1; ic2 >= 0; ic2--) { 814 for (ic2 = BOX_C2_ELEMS-1; ic2 >= 0; ic2--) {
819 » if (dist2 < *bptr) { 815 if (dist2 < *bptr) {
820 » *bptr = dist2; 816 *bptr = dist2;
821 » *cptr = (JSAMPLE) icolor; 817 *cptr = (JSAMPLE) icolor;
822 » } 818 }
823 » dist2 += xx2; 819 dist2 += xx2;
824 » xx2 += 2 * STEP_C2 * STEP_C2; 820 xx2 += 2 * STEP_C2 * STEP_C2;
825 » bptr++; 821 bptr++;
826 » cptr++; 822 cptr++;
827 » } 823 }
828 » dist1 += xx1; 824 dist1 += xx1;
829 » xx1 += 2 * STEP_C1 * STEP_C1; 825 xx1 += 2 * STEP_C1 * STEP_C1;
830 } 826 }
831 dist0 += xx0; 827 dist0 += xx0;
832 xx0 += 2 * STEP_C0 * STEP_C0; 828 xx0 += 2 * STEP_C0 * STEP_C0;
833 } 829 }
834 } 830 }
835 } 831 }
836 832
837 833
838 LOCAL(void) 834 LOCAL(void)
839 fill_inverse_cmap (j_decompress_ptr cinfo, int c0, int c1, int c2) 835 fill_inverse_cmap (j_decompress_ptr cinfo, int c0, int c1, int c2)
840 /* Fill the inverse-colormap entries in the update box that contains */ 836 /* Fill the inverse-colormap entries in the update box that contains */
841 /* histogram cell c0/c1/c2. (Only that one cell MUST be filled, but */ 837 /* histogram cell c0/c1/c2. (Only that one cell MUST be filled, but */
842 /* we can fill as many others as we wish.) */ 838 /* we can fill as many others as we wish.) */
843 { 839 {
844 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; 840 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;
845 hist3d histogram = cquantize->histogram; 841 hist3d histogram = cquantize->histogram;
846 int minc0, minc1, minc2;» /* lower left corner of update box */ 842 int minc0, minc1, minc2; /* lower left corner of update box */
847 int ic0, ic1, ic2; 843 int ic0, ic1, ic2;
848 register JSAMPLE * cptr;» /* pointer into bestcolor[] array */ 844 register JSAMPLE *cptr; /* pointer into bestcolor[] array */
849 register histptr cachep;» /* pointer into main cache array */ 845 register histptr cachep; /* pointer into main cache array */
850 /* This array lists the candidate colormap indexes. */ 846 /* This array lists the candidate colormap indexes. */
851 JSAMPLE colorlist[MAXNUMCOLORS]; 847 JSAMPLE colorlist[MAXNUMCOLORS];
852 int numcolors;» » /* number of candidate colors */ 848 int numcolors; /* number of candidate colors */
853 /* This array holds the actually closest colormap index for each cell. */ 849 /* This array holds the actually closest colormap index for each cell. */
854 JSAMPLE bestcolor[BOX_C0_ELEMS * BOX_C1_ELEMS * BOX_C2_ELEMS]; 850 JSAMPLE bestcolor[BOX_C0_ELEMS * BOX_C1_ELEMS * BOX_C2_ELEMS];
855 851
856 /* Convert cell coordinates to update box ID */ 852 /* Convert cell coordinates to update box ID */
857 c0 >>= BOX_C0_LOG; 853 c0 >>= BOX_C0_LOG;
858 c1 >>= BOX_C1_LOG; 854 c1 >>= BOX_C1_LOG;
859 c2 >>= BOX_C2_LOG; 855 c2 >>= BOX_C2_LOG;
860 856
861 /* Compute true coordinates of update box's origin corner. 857 /* Compute true coordinates of update box's origin corner.
862 * Actually we compute the coordinates of the center of the corner 858 * Actually we compute the coordinates of the center of the corner
863 * histogram cell, which are the lower bounds of the volume we care about. 859 * histogram cell, which are the lower bounds of the volume we care about.
864 */ 860 */
865 minc0 = (c0 << BOX_C0_SHIFT) + ((1 << C0_SHIFT) >> 1); 861 minc0 = (c0 << BOX_C0_SHIFT) + ((1 << C0_SHIFT) >> 1);
866 minc1 = (c1 << BOX_C1_SHIFT) + ((1 << C1_SHIFT) >> 1); 862 minc1 = (c1 << BOX_C1_SHIFT) + ((1 << C1_SHIFT) >> 1);
867 minc2 = (c2 << BOX_C2_SHIFT) + ((1 << C2_SHIFT) >> 1); 863 minc2 = (c2 << BOX_C2_SHIFT) + ((1 << C2_SHIFT) >> 1);
868 864
869 /* Determine which colormap entries are close enough to be candidates 865 /* Determine which colormap entries are close enough to be candidates
870 * for the nearest entry to some cell in the update box. 866 * for the nearest entry to some cell in the update box.
871 */ 867 */
872 numcolors = find_nearby_colors(cinfo, minc0, minc1, minc2, colorlist); 868 numcolors = find_nearby_colors(cinfo, minc0, minc1, minc2, colorlist);
873 869
874 /* Determine the actually nearest colors. */ 870 /* Determine the actually nearest colors. */
875 find_best_colors(cinfo, minc0, minc1, minc2, numcolors, colorlist, 871 find_best_colors(cinfo, minc0, minc1, minc2, numcolors, colorlist,
876 » » bestcolor); 872 bestcolor);
877 873
878 /* Save the best color numbers (plus 1) in the main cache array */ 874 /* Save the best color numbers (plus 1) in the main cache array */
879 c0 <<= BOX_C0_LOG;» » /* convert ID back to base cell indexes */ 875 c0 <<= BOX_C0_LOG; /* convert ID back to base cell indexes */
880 c1 <<= BOX_C1_LOG; 876 c1 <<= BOX_C1_LOG;
881 c2 <<= BOX_C2_LOG; 877 c2 <<= BOX_C2_LOG;
882 cptr = bestcolor; 878 cptr = bestcolor;
883 for (ic0 = 0; ic0 < BOX_C0_ELEMS; ic0++) { 879 for (ic0 = 0; ic0 < BOX_C0_ELEMS; ic0++) {
884 for (ic1 = 0; ic1 < BOX_C1_ELEMS; ic1++) { 880 for (ic1 = 0; ic1 < BOX_C1_ELEMS; ic1++) {
885 cachep = & histogram[c0+ic0][c1+ic1][c2]; 881 cachep = & histogram[c0+ic0][c1+ic1][c2];
886 for (ic2 = 0; ic2 < BOX_C2_ELEMS; ic2++) { 882 for (ic2 = 0; ic2 < BOX_C2_ELEMS; ic2++) {
887 » *cachep++ = (histcell) (GETJSAMPLE(*cptr++) + 1); 883 *cachep++ = (histcell) (GETJSAMPLE(*cptr++) + 1);
888 } 884 }
889 } 885 }
890 } 886 }
891 } 887 }
892 888
893 889
894 /* 890 /*
895 * Map some rows of pixels to the output colormapped representation. 891 * Map some rows of pixels to the output colormapped representation.
896 */ 892 */
897 893
898 METHODDEF(void) 894 METHODDEF(void)
899 pass2_no_dither (j_decompress_ptr cinfo, 895 pass2_no_dither (j_decompress_ptr cinfo,
900 » » JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows) 896 JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows)
901 /* This version performs no dithering */ 897 /* This version performs no dithering */
902 { 898 {
903 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; 899 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;
904 hist3d histogram = cquantize->histogram; 900 hist3d histogram = cquantize->histogram;
905 register JSAMPROW inptr, outptr; 901 register JSAMPROW inptr, outptr;
906 register histptr cachep; 902 register histptr cachep;
907 register int c0, c1, c2; 903 register int c0, c1, c2;
908 int row; 904 int row;
909 JDIMENSION col; 905 JDIMENSION col;
910 JDIMENSION width = cinfo->output_width; 906 JDIMENSION width = cinfo->output_width;
911 907
912 for (row = 0; row < num_rows; row++) { 908 for (row = 0; row < num_rows; row++) {
913 inptr = input_buf[row]; 909 inptr = input_buf[row];
914 outptr = output_buf[row]; 910 outptr = output_buf[row];
915 for (col = width; col > 0; col--) { 911 for (col = width; col > 0; col--) {
916 /* get pixel value and index into the cache */ 912 /* get pixel value and index into the cache */
917 c0 = GETJSAMPLE(*inptr++) >> C0_SHIFT; 913 c0 = GETJSAMPLE(*inptr++) >> C0_SHIFT;
918 c1 = GETJSAMPLE(*inptr++) >> C1_SHIFT; 914 c1 = GETJSAMPLE(*inptr++) >> C1_SHIFT;
919 c2 = GETJSAMPLE(*inptr++) >> C2_SHIFT; 915 c2 = GETJSAMPLE(*inptr++) >> C2_SHIFT;
920 cachep = & histogram[c0][c1][c2]; 916 cachep = & histogram[c0][c1][c2];
921 /* If we have not seen this color before, find nearest colormap entry */ 917 /* If we have not seen this color before, find nearest colormap entry */
922 /* and update the cache */ 918 /* and update the cache */
923 if (*cachep == 0) 919 if (*cachep == 0)
924 » fill_inverse_cmap(cinfo, c0,c1,c2); 920 fill_inverse_cmap(cinfo, c0,c1,c2);
925 /* Now emit the colormap index for this cell */ 921 /* Now emit the colormap index for this cell */
926 *outptr++ = (JSAMPLE) (*cachep - 1); 922 *outptr++ = (JSAMPLE) (*cachep - 1);
927 } 923 }
928 } 924 }
929 } 925 }
930 926
931 927
932 METHODDEF(void) 928 METHODDEF(void)
933 pass2_fs_dither (j_decompress_ptr cinfo, 929 pass2_fs_dither (j_decompress_ptr cinfo,
934 » » JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows) 930 JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows)
935 /* This version performs Floyd-Steinberg dithering */ 931 /* This version performs Floyd-Steinberg dithering */
936 { 932 {
937 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; 933 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;
938 hist3d histogram = cquantize->histogram; 934 hist3d histogram = cquantize->histogram;
939 register LOCFSERROR cur0, cur1, cur2;»/* current error or pixel value */ 935 register LOCFSERROR cur0, cur1, cur2; /* current error or pixel value */
940 LOCFSERROR belowerr0, belowerr1, belowerr2; /* error for pixel below cur */ 936 LOCFSERROR belowerr0, belowerr1, belowerr2; /* error for pixel below cur */
941 LOCFSERROR bpreverr0, bpreverr1, bpreverr2; /* error for below/prev col */ 937 LOCFSERROR bpreverr0, bpreverr1, bpreverr2; /* error for below/prev col */
942 register FSERRPTR errorptr;» /* => fserrors[] at column before current */ 938 register FSERRPTR errorptr; /* => fserrors[] at column before current */
943 JSAMPROW inptr;» » /* => current input pixel */ 939 JSAMPROW inptr; /* => current input pixel */
944 JSAMPROW outptr;» » /* => current output pixel */ 940 JSAMPROW outptr; /* => current output pixel */
945 histptr cachep; 941 histptr cachep;
946 int dir;» » » /* +1 or -1 depending on direction */ 942 int dir; /* +1 or -1 depending on direction */
947 int dir3;» » » /* 3*dir, for advancing inptr & errorptr */ 943 int dir3; /* 3*dir, for advancing inptr & errorptr */
948 int row; 944 int row;
949 JDIMENSION col; 945 JDIMENSION col;
950 JDIMENSION width = cinfo->output_width; 946 JDIMENSION width = cinfo->output_width;
951 JSAMPLE *range_limit = cinfo->sample_range_limit; 947 JSAMPLE *range_limit = cinfo->sample_range_limit;
952 int *error_limit = cquantize->error_limiter; 948 int *error_limit = cquantize->error_limiter;
953 JSAMPROW colormap0 = cinfo->colormap[0]; 949 JSAMPROW colormap0 = cinfo->colormap[0];
954 JSAMPROW colormap1 = cinfo->colormap[1]; 950 JSAMPROW colormap1 = cinfo->colormap[1];
955 JSAMPROW colormap2 = cinfo->colormap[2]; 951 JSAMPROW colormap2 = cinfo->colormap[2];
956 SHIFT_TEMPS 952 SHIFT_TEMPS
957 953
958 for (row = 0; row < num_rows; row++) { 954 for (row = 0; row < num_rows; row++) {
959 inptr = input_buf[row]; 955 inptr = input_buf[row];
960 outptr = output_buf[row]; 956 outptr = output_buf[row];
961 if (cquantize->on_odd_row) { 957 if (cquantize->on_odd_row) {
962 /* work right to left in this row */ 958 /* work right to left in this row */
963 inptr += (width-1) * 3;» /* so point to rightmost pixel */ 959 inptr += (width-1) * 3; /* so point to rightmost pixel */
964 outptr += width-1; 960 outptr += width-1;
965 dir = -1; 961 dir = -1;
966 dir3 = -3; 962 dir3 = -3;
967 errorptr = cquantize->fserrors + (width+1)*3; /* => entry after last colum n */ 963 errorptr = cquantize->fserrors + (width+1)*3; /* => entry after last colum n */
968 cquantize->on_odd_row = FALSE; /* flip for next time */ 964 cquantize->on_odd_row = FALSE; /* flip for next time */
969 } else { 965 } else {
970 /* work left to right in this row */ 966 /* work left to right in this row */
971 dir = 1; 967 dir = 1;
972 dir3 = 3; 968 dir3 = 3;
973 errorptr = cquantize->fserrors; /* => entry before first real column */ 969 errorptr = cquantize->fserrors; /* => entry before first real column */
(...skipping 31 matching lines...) Expand 10 before | Expand all | Expand 10 after
1005 cur1 += GETJSAMPLE(inptr[1]); 1001 cur1 += GETJSAMPLE(inptr[1]);
1006 cur2 += GETJSAMPLE(inptr[2]); 1002 cur2 += GETJSAMPLE(inptr[2]);
1007 cur0 = GETJSAMPLE(range_limit[cur0]); 1003 cur0 = GETJSAMPLE(range_limit[cur0]);
1008 cur1 = GETJSAMPLE(range_limit[cur1]); 1004 cur1 = GETJSAMPLE(range_limit[cur1]);
1009 cur2 = GETJSAMPLE(range_limit[cur2]); 1005 cur2 = GETJSAMPLE(range_limit[cur2]);
1010 /* Index into the cache with adjusted pixel value */ 1006 /* Index into the cache with adjusted pixel value */
1011 cachep = & histogram[cur0>>C0_SHIFT][cur1>>C1_SHIFT][cur2>>C2_SHIFT]; 1007 cachep = & histogram[cur0>>C0_SHIFT][cur1>>C1_SHIFT][cur2>>C2_SHIFT];
1012 /* If we have not seen this color before, find nearest colormap */ 1008 /* If we have not seen this color before, find nearest colormap */
1013 /* entry and update the cache */ 1009 /* entry and update the cache */
1014 if (*cachep == 0) 1010 if (*cachep == 0)
1015 » fill_inverse_cmap(cinfo, cur0>>C0_SHIFT,cur1>>C1_SHIFT,cur2>>C2_SHIFT); 1011 fill_inverse_cmap(cinfo, cur0>>C0_SHIFT,cur1>>C1_SHIFT,cur2>>C2_SHIFT);
1016 /* Now emit the colormap index for this cell */ 1012 /* Now emit the colormap index for this cell */
1017 { register int pixcode = *cachep - 1; 1013 { register int pixcode = *cachep - 1;
1018 » *outptr = (JSAMPLE) pixcode; 1014 *outptr = (JSAMPLE) pixcode;
1019 » /* Compute representation error for this pixel */ 1015 /* Compute representation error for this pixel */
1020 » cur0 -= GETJSAMPLE(colormap0[pixcode]); 1016 cur0 -= GETJSAMPLE(colormap0[pixcode]);
1021 » cur1 -= GETJSAMPLE(colormap1[pixcode]); 1017 cur1 -= GETJSAMPLE(colormap1[pixcode]);
1022 » cur2 -= GETJSAMPLE(colormap2[pixcode]); 1018 cur2 -= GETJSAMPLE(colormap2[pixcode]);
1023 } 1019 }
1024 /* Compute error fractions to be propagated to adjacent pixels. 1020 /* Compute error fractions to be propagated to adjacent pixels.
1025 * Add these into the running sums, and simultaneously shift the 1021 * Add these into the running sums, and simultaneously shift the
1026 * next-line error sums left by 1 column. 1022 * next-line error sums left by 1 column.
1027 */ 1023 */
1028 { register LOCFSERROR bnexterr, delta; 1024 { register LOCFSERROR bnexterr;
1029 1025
1030 » bnexterr = cur0;» /* Process component 0 */ 1026 bnexterr = cur0; /* Process component 0 */
1031 » delta = cur0 * 2; 1027 errorptr[0] = (FSERROR) (bpreverr0 + cur0 * 3);
1032 » cur0 += delta;» » /* form error * 3 */ 1028 bpreverr0 = belowerr0 + cur0 * 5;
1033 » errorptr[0] = (FSERROR) (bpreverr0 + cur0); 1029 belowerr0 = bnexterr;
1034 » cur0 += delta;» » /* form error * 5 */ 1030 cur0 *= 7;
1035 » bpreverr0 = belowerr0 + cur0; 1031 bnexterr = cur1; /* Process component 1 */
1036 » belowerr0 = bnexterr; 1032 errorptr[1] = (FSERROR) (bpreverr1 + cur1 * 3);
1037 » cur0 += delta;» » /* form error * 7 */ 1033 bpreverr1 = belowerr1 + cur1 * 5;
1038 » bnexterr = cur1;» /* Process component 1 */ 1034 belowerr1 = bnexterr;
1039 » delta = cur1 * 2; 1035 cur1 *= 7;
1040 » cur1 += delta;» » /* form error * 3 */ 1036 bnexterr = cur2; /* Process component 2 */
1041 » errorptr[1] = (FSERROR) (bpreverr1 + cur1); 1037 errorptr[2] = (FSERROR) (bpreverr2 + cur2 * 3);
1042 » cur1 += delta;» » /* form error * 5 */ 1038 bpreverr2 = belowerr2 + cur2 * 5;
1043 » bpreverr1 = belowerr1 + cur1; 1039 belowerr2 = bnexterr;
1044 » belowerr1 = bnexterr; 1040 cur2 *= 7;
1045 » cur1 += delta;» » /* form error * 7 */
1046 » bnexterr = cur2;» /* Process component 2 */
1047 » delta = cur2 * 2;
1048 » cur2 += delta;» » /* form error * 3 */
1049 » errorptr[2] = (FSERROR) (bpreverr2 + cur2);
1050 » cur2 += delta;» » /* form error * 5 */
1051 » bpreverr2 = belowerr2 + cur2;
1052 » belowerr2 = bnexterr;
1053 » cur2 += delta;» » /* form error * 7 */
1054 } 1041 }
1055 /* At this point curN contains the 7/16 error value to be propagated 1042 /* At this point curN contains the 7/16 error value to be propagated
1056 * to the next pixel on the current line, and all the errors for the 1043 * to the next pixel on the current line, and all the errors for the
1057 * next line have been shifted over. We are therefore ready to move on. 1044 * next line have been shifted over. We are therefore ready to move on.
1058 */ 1045 */
1059 inptr += dir3;» » /* Advance pixel pointers to next column */ 1046 inptr += dir3; /* Advance pixel pointers to next column */
1060 outptr += dir; 1047 outptr += dir;
1061 errorptr += dir3;»» /* advance errorptr to current column */ 1048 errorptr += dir3; /* advance errorptr to current column */
1062 } 1049 }
1063 /* Post-loop cleanup: we must unload the final error values into the 1050 /* Post-loop cleanup: we must unload the final error values into the
1064 * final fserrors[] entry. Note we need not unload belowerrN because 1051 * final fserrors[] entry. Note we need not unload belowerrN because
1065 * it is for the dummy column before or after the actual array. 1052 * it is for the dummy column before or after the actual array.
1066 */ 1053 */
1067 errorptr[0] = (FSERROR) bpreverr0; /* unload prev errs into array */ 1054 errorptr[0] = (FSERROR) bpreverr0; /* unload prev errs into array */
1068 errorptr[1] = (FSERROR) bpreverr1; 1055 errorptr[1] = (FSERROR) bpreverr1;
1069 errorptr[2] = (FSERROR) bpreverr2; 1056 errorptr[2] = (FSERROR) bpreverr2;
1070 } 1057 }
1071 } 1058 }
(...skipping 14 matching lines...) Expand all
1086 * A simple clamping of the error values to about +- MAXJSAMPLE/8 works pretty 1073 * A simple clamping of the error values to about +- MAXJSAMPLE/8 works pretty
1087 * well, but the smoother transfer function used below is even better. Thanks 1074 * well, but the smoother transfer function used below is even better. Thanks
1088 * to Aaron Giles for this idea. 1075 * to Aaron Giles for this idea.
1089 */ 1076 */
1090 1077
1091 LOCAL(void) 1078 LOCAL(void)
1092 init_error_limit (j_decompress_ptr cinfo) 1079 init_error_limit (j_decompress_ptr cinfo)
1093 /* Allocate and fill in the error_limiter table */ 1080 /* Allocate and fill in the error_limiter table */
1094 { 1081 {
1095 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; 1082 my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;
1096 int * table; 1083 int *table;
1097 int in, out; 1084 int in, out;
1098 1085
1099 table = (int *) (*cinfo->mem->alloc_small) 1086 table = (int *) (*cinfo->mem->alloc_small)
1100 ((j_common_ptr) cinfo, JPOOL_IMAGE, (MAXJSAMPLE*2+1) * SIZEOF(int)); 1087 ((j_common_ptr) cinfo, JPOOL_IMAGE, (MAXJSAMPLE*2+1) * sizeof(int));
1101 table += MAXJSAMPLE;» » /* so can index -MAXJSAMPLE .. +MAXJSAMPLE */ 1088 table += MAXJSAMPLE; /* so can index -MAXJSAMPLE .. +MAXJSAMPLE */
1102 cquantize->error_limiter = table; 1089 cquantize->error_limiter = table;
1103 1090
1104 #define STEPSIZE ((MAXJSAMPLE+1)/16) 1091 #define STEPSIZE ((MAXJSAMPLE+1)/16)
1105 /* Map errors 1:1 up to +- MAXJSAMPLE/16 */ 1092 /* Map errors 1:1 up to +- MAXJSAMPLE/16 */
1106 out = 0; 1093 out = 0;
1107 for (in = 0; in < STEPSIZE; in++, out++) { 1094 for (in = 0; in < STEPSIZE; in++, out++) {
1108 table[in] = out; table[-in] = -out; 1095 table[in] = out; table[-in] = -out;
1109 } 1096 }
1110 /* Map errors 1:2 up to +- 3*MAXJSAMPLE/16 */ 1097 /* Map errors 1:2 up to +- 3*MAXJSAMPLE/16 */
1111 for (; in < STEPSIZE*3; in++, out += (in&1) ? 0 : 1) { 1098 for (; in < STEPSIZE*3; in++, out += (in&1) ? 0 : 1) {
(...skipping 62 matching lines...) Expand 10 before | Expand all | Expand 10 after
1174 1161
1175 /* Make sure color count is acceptable */ 1162 /* Make sure color count is acceptable */
1176 i = cinfo->actual_number_of_colors; 1163 i = cinfo->actual_number_of_colors;
1177 if (i < 1) 1164 if (i < 1)
1178 ERREXIT1(cinfo, JERR_QUANT_FEW_COLORS, 1); 1165 ERREXIT1(cinfo, JERR_QUANT_FEW_COLORS, 1);
1179 if (i > MAXNUMCOLORS) 1166 if (i > MAXNUMCOLORS)
1180 ERREXIT1(cinfo, JERR_QUANT_MANY_COLORS, MAXNUMCOLORS); 1167 ERREXIT1(cinfo, JERR_QUANT_MANY_COLORS, MAXNUMCOLORS);
1181 1168
1182 if (cinfo->dither_mode == JDITHER_FS) { 1169 if (cinfo->dither_mode == JDITHER_FS) {
1183 size_t arraysize = (size_t) ((cinfo->output_width + 2) * 1170 size_t arraysize = (size_t) ((cinfo->output_width + 2) *
1184 » » » » (3 * SIZEOF(FSERROR))); 1171 (3 * sizeof(FSERROR)));
1185 /* Allocate Floyd-Steinberg workspace if we didn't already. */ 1172 /* Allocate Floyd-Steinberg workspace if we didn't already. */
1186 if (cquantize->fserrors == NULL) 1173 if (cquantize->fserrors == NULL)
1187 » cquantize->fserrors = (FSERRPTR) (*cinfo->mem->alloc_large) 1174 cquantize->fserrors = (FSERRPTR) (*cinfo->mem->alloc_large)
1188 » ((j_common_ptr) cinfo, JPOOL_IMAGE, arraysize); 1175 ((j_common_ptr) cinfo, JPOOL_IMAGE, arraysize);
1189 /* Initialize the propagated errors to zero. */ 1176 /* Initialize the propagated errors to zero. */
1190 jzero_far((void FAR *) cquantize->fserrors, arraysize); 1177 jzero_far((void *) cquantize->fserrors, arraysize);
1191 /* Make the error-limit table if we didn't already. */ 1178 /* Make the error-limit table if we didn't already. */
1192 if (cquantize->error_limiter == NULL) 1179 if (cquantize->error_limiter == NULL)
1193 » init_error_limit(cinfo); 1180 init_error_limit(cinfo);
1194 cquantize->on_odd_row = FALSE; 1181 cquantize->on_odd_row = FALSE;
1195 } 1182 }
1196 1183
1197 } 1184 }
1198 /* Zero the histogram or inverse color map, if necessary */ 1185 /* Zero the histogram or inverse color map, if necessary */
1199 if (cquantize->needs_zeroed) { 1186 if (cquantize->needs_zeroed) {
1200 for (i = 0; i < HIST_C0_ELEMS; i++) { 1187 for (i = 0; i < HIST_C0_ELEMS; i++) {
1201 jzero_far((void FAR *) histogram[i], 1188 jzero_far((void *) histogram[i],
1202 » » HIST_C1_ELEMS*HIST_C2_ELEMS * SIZEOF(histcell)); 1189 HIST_C1_ELEMS*HIST_C2_ELEMS * sizeof(histcell));
1203 } 1190 }
1204 cquantize->needs_zeroed = FALSE; 1191 cquantize->needs_zeroed = FALSE;
1205 } 1192 }
1206 } 1193 }
1207 1194
1208 1195
1209 /* 1196 /*
1210 * Switch to a new external colormap between output passes. 1197 * Switch to a new external colormap between output passes.
1211 */ 1198 */
1212 1199
(...skipping 12 matching lines...) Expand all
1225 */ 1212 */
1226 1213
1227 GLOBAL(void) 1214 GLOBAL(void)
1228 jinit_2pass_quantizer (j_decompress_ptr cinfo) 1215 jinit_2pass_quantizer (j_decompress_ptr cinfo)
1229 { 1216 {
1230 my_cquantize_ptr cquantize; 1217 my_cquantize_ptr cquantize;
1231 int i; 1218 int i;
1232 1219
1233 cquantize = (my_cquantize_ptr) 1220 cquantize = (my_cquantize_ptr)
1234 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, 1221 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
1235 » » » » SIZEOF(my_cquantizer)); 1222 sizeof(my_cquantizer));
1236 cinfo->cquantize = (struct jpeg_color_quantizer *) cquantize; 1223 cinfo->cquantize = (struct jpeg_color_quantizer *) cquantize;
1237 cquantize->pub.start_pass = start_pass_2_quant; 1224 cquantize->pub.start_pass = start_pass_2_quant;
1238 cquantize->pub.new_color_map = new_color_map_2_quant; 1225 cquantize->pub.new_color_map = new_color_map_2_quant;
1239 cquantize->fserrors = NULL;» /* flag optional arrays not allocated */ 1226 cquantize->fserrors = NULL; /* flag optional arrays not allocated */
1240 cquantize->error_limiter = NULL; 1227 cquantize->error_limiter = NULL;
1241 1228
1242 /* Make sure jdmaster didn't give me a case I can't handle */ 1229 /* Make sure jdmaster didn't give me a case I can't handle */
1243 if (cinfo->out_color_components != 3) 1230 if (cinfo->out_color_components != 3)
1244 ERREXIT(cinfo, JERR_NOTIMPL); 1231 ERREXIT(cinfo, JERR_NOTIMPL);
1245 1232
1246 /* Allocate the histogram/inverse colormap storage */ 1233 /* Allocate the histogram/inverse colormap storage */
1247 cquantize->histogram = (hist3d) (*cinfo->mem->alloc_small) 1234 cquantize->histogram = (hist3d) (*cinfo->mem->alloc_small)
1248 ((j_common_ptr) cinfo, JPOOL_IMAGE, HIST_C0_ELEMS * SIZEOF(hist2d)); 1235 ((j_common_ptr) cinfo, JPOOL_IMAGE, HIST_C0_ELEMS * sizeof(hist2d));
1249 for (i = 0; i < HIST_C0_ELEMS; i++) { 1236 for (i = 0; i < HIST_C0_ELEMS; i++) {
1250 cquantize->histogram[i] = (hist2d) (*cinfo->mem->alloc_large) 1237 cquantize->histogram[i] = (hist2d) (*cinfo->mem->alloc_large)
1251 ((j_common_ptr) cinfo, JPOOL_IMAGE, 1238 ((j_common_ptr) cinfo, JPOOL_IMAGE,
1252 HIST_C1_ELEMS*HIST_C2_ELEMS * SIZEOF(histcell)); 1239 HIST_C1_ELEMS*HIST_C2_ELEMS * sizeof(histcell));
1253 } 1240 }
1254 cquantize->needs_zeroed = TRUE; /* histogram is garbage now */ 1241 cquantize->needs_zeroed = TRUE; /* histogram is garbage now */
1255 1242
1256 /* Allocate storage for the completed colormap, if required. 1243 /* Allocate storage for the completed colormap, if required.
1257 * We do this now since it is FAR storage and may affect 1244 * We do this now since it may affect the memory manager's space
1258 * the memory manager's space calculations. 1245 * calculations.
1259 */ 1246 */
1260 if (cinfo->enable_2pass_quant) { 1247 if (cinfo->enable_2pass_quant) {
1261 /* Make sure color count is acceptable */ 1248 /* Make sure color count is acceptable */
1262 int desired = cinfo->desired_number_of_colors; 1249 int desired = cinfo->desired_number_of_colors;
1263 /* Lower bound on # of colors ... somewhat arbitrary as long as > 0 */ 1250 /* Lower bound on # of colors ... somewhat arbitrary as long as > 0 */
1264 if (desired < 8) 1251 if (desired < 8)
1265 ERREXIT1(cinfo, JERR_QUANT_FEW_COLORS, 8); 1252 ERREXIT1(cinfo, JERR_QUANT_FEW_COLORS, 8);
1266 /* Make sure colormap indexes can be represented by JSAMPLEs */ 1253 /* Make sure colormap indexes can be represented by JSAMPLEs */
1267 if (desired > MAXNUMCOLORS) 1254 if (desired > MAXNUMCOLORS)
1268 ERREXIT1(cinfo, JERR_QUANT_MANY_COLORS, MAXNUMCOLORS); 1255 ERREXIT1(cinfo, JERR_QUANT_MANY_COLORS, MAXNUMCOLORS);
1269 cquantize->sv_colormap = (*cinfo->mem->alloc_sarray) 1256 cquantize->sv_colormap = (*cinfo->mem->alloc_sarray)
1270 ((j_common_ptr) cinfo,JPOOL_IMAGE, (JDIMENSION) desired, (JDIMENSION) 3); 1257 ((j_common_ptr) cinfo,JPOOL_IMAGE, (JDIMENSION) desired, (JDIMENSION) 3);
1271 cquantize->desired = desired; 1258 cquantize->desired = desired;
1272 } else 1259 } else
1273 cquantize->sv_colormap = NULL; 1260 cquantize->sv_colormap = NULL;
1274 1261
1275 /* Only F-S dithering or no dithering is supported. */ 1262 /* Only F-S dithering or no dithering is supported. */
1276 /* If user asks for ordered dither, give him F-S. */ 1263 /* If user asks for ordered dither, give him F-S. */
1277 if (cinfo->dither_mode != JDITHER_NONE) 1264 if (cinfo->dither_mode != JDITHER_NONE)
1278 cinfo->dither_mode = JDITHER_FS; 1265 cinfo->dither_mode = JDITHER_FS;
1279 1266
1280 /* Allocate Floyd-Steinberg workspace if necessary. 1267 /* Allocate Floyd-Steinberg workspace if necessary.
1281 * This isn't really needed until pass 2, but again it is FAR storage. 1268 * This isn't really needed until pass 2, but again it may affect the memory
1282 * Although we will cope with a later change in dither_mode, 1269 * manager's space calculations. Although we will cope with a later change
1283 * we do not promise to honor max_memory_to_use if dither_mode changes. 1270 * in dither_mode, we do not promise to honor max_memory_to_use if
1271 * dither_mode changes.
1284 */ 1272 */
1285 if (cinfo->dither_mode == JDITHER_FS) { 1273 if (cinfo->dither_mode == JDITHER_FS) {
1286 cquantize->fserrors = (FSERRPTR) (*cinfo->mem->alloc_large) 1274 cquantize->fserrors = (FSERRPTR) (*cinfo->mem->alloc_large)
1287 ((j_common_ptr) cinfo, JPOOL_IMAGE, 1275 ((j_common_ptr) cinfo, JPOOL_IMAGE,
1288 (size_t) ((cinfo->output_width + 2) * (3 * SIZEOF(FSERROR)))); 1276 (size_t) ((cinfo->output_width + 2) * (3 * sizeof(FSERROR))));
1289 /* Might as well create the error-limiting table too. */ 1277 /* Might as well create the error-limiting table too. */
1290 init_error_limit(cinfo); 1278 init_error_limit(cinfo);
1291 } 1279 }
1292 } 1280 }
1293 1281
1294 #endif /* QUANT_2PASS_SUPPORTED */ 1282 #endif /* QUANT_2PASS_SUPPORTED */
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