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1 /*
2  * jdcolor.c
3  *
4  * This file was part of the Independent JPEG Group's software:
5  * Copyright (C) 1991-1997, Thomas G. Lane.
6  * Modified 2011 by Guido Vollbeding.
7  * libjpeg-turbo Modifications:
8  * Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
9  * Copyright (C) 2009, 2011-2012, 2014-2015, D. R. Commander.
10  * Copyright (C) 2013, Linaro Limited.
11  * For conditions of distribution and use, see the accompanying README.ijg
12  * file.
13  *
14  * This file contains output colorspace conversion routines.
15  */
16 
17 #define JPEG_INTERNALS
18 #include "jinclude.h"
19 #include "jpeglib.h"
20 #include "jsimd.h"
21 #include "jconfigint.h"
22 
23 
24 /* Private subobject */
25 
26 typedef struct {
27   struct jpeg_color_deconverter pub; /* public fields */
28 
29   /* Private state for YCC->RGB conversion */
30   int *Cr_r_tab;                /* => table for Cr to R conversion */
31   int *Cb_b_tab;                /* => table for Cb to B conversion */
32   JLONG *Cr_g_tab;              /* => table for Cr to G conversion */
33   JLONG *Cb_g_tab;              /* => table for Cb to G conversion */
34 
35   /* Private state for RGB->Y conversion */
36   JLONG *rgb_y_tab;             /* => table for RGB to Y conversion */
37 } my_color_deconverter;
38 
39 typedef my_color_deconverter *my_cconvert_ptr;
40 
41 
42 /**************** YCbCr -> RGB conversion: most common case **************/
43 /****************   RGB -> Y   conversion: less common case **************/
44 
45 /*
46  * YCbCr is defined per CCIR 601-1, except that Cb and Cr are
47  * normalized to the range 0..MAXJSAMPLE rather than -0.5 .. 0.5.
48  * The conversion equations to be implemented are therefore
49  *
50  *      R = Y                + 1.40200 * Cr
51  *      G = Y - 0.34414 * Cb - 0.71414 * Cr
52  *      B = Y + 1.77200 * Cb
53  *
54  *      Y = 0.29900 * R + 0.58700 * G + 0.11400 * B
55  *
56  * where Cb and Cr represent the incoming values less CENTERJSAMPLE.
57  * (These numbers are derived from TIFF 6.0 section 21, dated 3-June-92.)
58  *
59  * To avoid floating-point arithmetic, we represent the fractional constants
60  * as integers scaled up by 2^16 (about 4 digits precision); we have to divide
61  * the products by 2^16, with appropriate rounding, to get the correct answer.
62  * Notice that Y, being an integral input, does not contribute any fraction
63  * so it need not participate in the rounding.
64  *
65  * For even more speed, we avoid doing any multiplications in the inner loop
66  * by precalculating the constants times Cb and Cr for all possible values.
67  * For 8-bit JSAMPLEs this is very reasonable (only 256 entries per table);
68  * for 12-bit samples it is still acceptable.  It's not very reasonable for
69  * 16-bit samples, but if you want lossless storage you shouldn't be changing
70  * colorspace anyway.
71  * The Cr=>R and Cb=>B values can be rounded to integers in advance; the
72  * values for the G calculation are left scaled up, since we must add them
73  * together before rounding.
74  */
75 
76 #define SCALEBITS       16      /* speediest right-shift on some machines */
77 #define ONE_HALF        ((JLONG) 1 << (SCALEBITS-1))
78 #define FIX(x)          ((JLONG) ((x) * (1L<<SCALEBITS) + 0.5))
79 
80 /* We allocate one big table for RGB->Y conversion and divide it up into
81  * three parts, instead of doing three alloc_small requests.  This lets us
82  * use a single table base address, which can be held in a register in the
83  * inner loops on many machines (more than can hold all three addresses,
84  * anyway).
85  */
86 
87 #define R_Y_OFF         0                       /* offset to R => Y section */
88 #define G_Y_OFF         (1*(MAXJSAMPLE+1))      /* offset to G => Y section */
89 #define B_Y_OFF         (2*(MAXJSAMPLE+1))      /* etc. */
90 #define TABLE_SIZE      (3*(MAXJSAMPLE+1))
91 
92 
93 /* Include inline routines for colorspace extensions */
94 
95 #include "jdcolext.c"
96 #undef RGB_RED
97 #undef RGB_GREEN
98 #undef RGB_BLUE
99 #undef RGB_PIXELSIZE
100 
101 #define RGB_RED EXT_RGB_RED
102 #define RGB_GREEN EXT_RGB_GREEN
103 #define RGB_BLUE EXT_RGB_BLUE
104 #define RGB_PIXELSIZE EXT_RGB_PIXELSIZE
105 #define ycc_rgb_convert_internal ycc_extrgb_convert_internal
106 #define gray_rgb_convert_internal gray_extrgb_convert_internal
107 #define rgb_rgb_convert_internal rgb_extrgb_convert_internal
108 #include "jdcolext.c"
109 #undef RGB_RED
110 #undef RGB_GREEN
111 #undef RGB_BLUE
112 #undef RGB_PIXELSIZE
113 #undef ycc_rgb_convert_internal
114 #undef gray_rgb_convert_internal
115 #undef rgb_rgb_convert_internal
116 
117 #define RGB_RED EXT_RGBX_RED
118 #define RGB_GREEN EXT_RGBX_GREEN
119 #define RGB_BLUE EXT_RGBX_BLUE
120 #define RGB_ALPHA 3
121 #define RGB_PIXELSIZE EXT_RGBX_PIXELSIZE
122 #define ycc_rgb_convert_internal ycc_extrgbx_convert_internal
123 #define gray_rgb_convert_internal gray_extrgbx_convert_internal
124 #define rgb_rgb_convert_internal rgb_extrgbx_convert_internal
125 #include "jdcolext.c"
126 #undef RGB_RED
127 #undef RGB_GREEN
128 #undef RGB_BLUE
129 #undef RGB_ALPHA
130 #undef RGB_PIXELSIZE
131 #undef ycc_rgb_convert_internal
132 #undef gray_rgb_convert_internal
133 #undef rgb_rgb_convert_internal
134 
135 #define RGB_RED EXT_BGR_RED
136 #define RGB_GREEN EXT_BGR_GREEN
137 #define RGB_BLUE EXT_BGR_BLUE
138 #define RGB_PIXELSIZE EXT_BGR_PIXELSIZE
139 #define ycc_rgb_convert_internal ycc_extbgr_convert_internal
140 #define gray_rgb_convert_internal gray_extbgr_convert_internal
141 #define rgb_rgb_convert_internal rgb_extbgr_convert_internal
142 #include "jdcolext.c"
143 #undef RGB_RED
144 #undef RGB_GREEN
145 #undef RGB_BLUE
146 #undef RGB_PIXELSIZE
147 #undef ycc_rgb_convert_internal
148 #undef gray_rgb_convert_internal
149 #undef rgb_rgb_convert_internal
150 
151 #define RGB_RED EXT_BGRX_RED
152 #define RGB_GREEN EXT_BGRX_GREEN
153 #define RGB_BLUE EXT_BGRX_BLUE
154 #define RGB_ALPHA 3
155 #define RGB_PIXELSIZE EXT_BGRX_PIXELSIZE
156 #define ycc_rgb_convert_internal ycc_extbgrx_convert_internal
157 #define gray_rgb_convert_internal gray_extbgrx_convert_internal
158 #define rgb_rgb_convert_internal rgb_extbgrx_convert_internal
159 #include "jdcolext.c"
160 #undef RGB_RED
161 #undef RGB_GREEN
162 #undef RGB_BLUE
163 #undef RGB_ALPHA
164 #undef RGB_PIXELSIZE
165 #undef ycc_rgb_convert_internal
166 #undef gray_rgb_convert_internal
167 #undef rgb_rgb_convert_internal
168 
169 #define RGB_RED EXT_XBGR_RED
170 #define RGB_GREEN EXT_XBGR_GREEN
171 #define RGB_BLUE EXT_XBGR_BLUE
172 #define RGB_ALPHA 0
173 #define RGB_PIXELSIZE EXT_XBGR_PIXELSIZE
174 #define ycc_rgb_convert_internal ycc_extxbgr_convert_internal
175 #define gray_rgb_convert_internal gray_extxbgr_convert_internal
176 #define rgb_rgb_convert_internal rgb_extxbgr_convert_internal
177 #include "jdcolext.c"
178 #undef RGB_RED
179 #undef RGB_GREEN
180 #undef RGB_BLUE
181 #undef RGB_ALPHA
182 #undef RGB_PIXELSIZE
183 #undef ycc_rgb_convert_internal
184 #undef gray_rgb_convert_internal
185 #undef rgb_rgb_convert_internal
186 
187 #define RGB_RED EXT_XRGB_RED
188 #define RGB_GREEN EXT_XRGB_GREEN
189 #define RGB_BLUE EXT_XRGB_BLUE
190 #define RGB_ALPHA 0
191 #define RGB_PIXELSIZE EXT_XRGB_PIXELSIZE
192 #define ycc_rgb_convert_internal ycc_extxrgb_convert_internal
193 #define gray_rgb_convert_internal gray_extxrgb_convert_internal
194 #define rgb_rgb_convert_internal rgb_extxrgb_convert_internal
195 #include "jdcolext.c"
196 #undef RGB_RED
197 #undef RGB_GREEN
198 #undef RGB_BLUE
199 #undef RGB_ALPHA
200 #undef RGB_PIXELSIZE
201 #undef ycc_rgb_convert_internal
202 #undef gray_rgb_convert_internal
203 #undef rgb_rgb_convert_internal
204 
205 
206 /*
207  * Initialize tables for YCC->RGB colorspace conversion.
208  */
209 
210 LOCAL(void)
build_ycc_rgb_table(j_decompress_ptr cinfo)211 build_ycc_rgb_table (j_decompress_ptr cinfo)
212 {
213   my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
214   int i;
215   JLONG x;
216   SHIFT_TEMPS
217 
218   cconvert->Cr_r_tab = (int *)
219     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
220                                 (MAXJSAMPLE+1) * sizeof(int));
221   cconvert->Cb_b_tab = (int *)
222     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
223                                 (MAXJSAMPLE+1) * sizeof(int));
224   cconvert->Cr_g_tab = (JLONG *)
225     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
226                                 (MAXJSAMPLE+1) * sizeof(JLONG));
227   cconvert->Cb_g_tab = (JLONG *)
228     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
229                                 (MAXJSAMPLE+1) * sizeof(JLONG));
230 
231   for (i = 0, x = -CENTERJSAMPLE; i <= MAXJSAMPLE; i++, x++) {
232     /* i is the actual input pixel value, in the range 0..MAXJSAMPLE */
233     /* The Cb or Cr value we are thinking of is x = i - CENTERJSAMPLE */
234     /* Cr=>R value is nearest int to 1.40200 * x */
235     cconvert->Cr_r_tab[i] = (int)
236                     RIGHT_SHIFT(FIX(1.40200) * x + ONE_HALF, SCALEBITS);
237     /* Cb=>B value is nearest int to 1.77200 * x */
238     cconvert->Cb_b_tab[i] = (int)
239                     RIGHT_SHIFT(FIX(1.77200) * x + ONE_HALF, SCALEBITS);
240     /* Cr=>G value is scaled-up -0.71414 * x */
241     cconvert->Cr_g_tab[i] = (- FIX(0.71414)) * x;
242     /* Cb=>G value is scaled-up -0.34414 * x */
243     /* We also add in ONE_HALF so that need not do it in inner loop */
244     cconvert->Cb_g_tab[i] = (- FIX(0.34414)) * x + ONE_HALF;
245   }
246 }
247 
248 
249 /*
250  * Convert some rows of samples to the output colorspace.
251  */
252 
253 METHODDEF(void)
ycc_rgb_convert(j_decompress_ptr cinfo,JSAMPIMAGE input_buf,JDIMENSION input_row,JSAMPARRAY output_buf,int num_rows)254 ycc_rgb_convert (j_decompress_ptr cinfo,
255                  JSAMPIMAGE input_buf, JDIMENSION input_row,
256                  JSAMPARRAY output_buf, int num_rows)
257 {
258   switch (cinfo->out_color_space) {
259     case JCS_EXT_RGB:
260       ycc_extrgb_convert_internal(cinfo, input_buf, input_row, output_buf,
261                                   num_rows);
262       break;
263     case JCS_EXT_RGBX:
264     case JCS_EXT_RGBA:
265       ycc_extrgbx_convert_internal(cinfo, input_buf, input_row, output_buf,
266                                    num_rows);
267       break;
268     case JCS_EXT_BGR:
269       ycc_extbgr_convert_internal(cinfo, input_buf, input_row, output_buf,
270                                   num_rows);
271       break;
272     case JCS_EXT_BGRX:
273     case JCS_EXT_BGRA:
274       ycc_extbgrx_convert_internal(cinfo, input_buf, input_row, output_buf,
275                                    num_rows);
276       break;
277     case JCS_EXT_XBGR:
278     case JCS_EXT_ABGR:
279       ycc_extxbgr_convert_internal(cinfo, input_buf, input_row, output_buf,
280                                    num_rows);
281       break;
282     case JCS_EXT_XRGB:
283     case JCS_EXT_ARGB:
284       ycc_extxrgb_convert_internal(cinfo, input_buf, input_row, output_buf,
285                                    num_rows);
286       break;
287     default:
288       ycc_rgb_convert_internal(cinfo, input_buf, input_row, output_buf,
289                                num_rows);
290       break;
291   }
292 }
293 
294 
295 /**************** Cases other than YCbCr -> RGB **************/
296 
297 
298 /*
299  * Initialize for RGB->grayscale colorspace conversion.
300  */
301 
302 LOCAL(void)
build_rgb_y_table(j_decompress_ptr cinfo)303 build_rgb_y_table (j_decompress_ptr cinfo)
304 {
305   my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
306   JLONG *rgb_y_tab;
307   JLONG i;
308 
309   /* Allocate and fill in the conversion tables. */
310   cconvert->rgb_y_tab = rgb_y_tab = (JLONG *)
311     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
312                                 (TABLE_SIZE * sizeof(JLONG)));
313 
314   for (i = 0; i <= MAXJSAMPLE; i++) {
315     rgb_y_tab[i+R_Y_OFF] = FIX(0.29900) * i;
316     rgb_y_tab[i+G_Y_OFF] = FIX(0.58700) * i;
317     rgb_y_tab[i+B_Y_OFF] = FIX(0.11400) * i + ONE_HALF;
318   }
319 }
320 
321 
322 /*
323  * Convert RGB to grayscale.
324  */
325 
326 METHODDEF(void)
rgb_gray_convert(j_decompress_ptr cinfo,JSAMPIMAGE input_buf,JDIMENSION input_row,JSAMPARRAY output_buf,int num_rows)327 rgb_gray_convert (j_decompress_ptr cinfo,
328                   JSAMPIMAGE input_buf, JDIMENSION input_row,
329                   JSAMPARRAY output_buf, int num_rows)
330 {
331   my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
332   register int r, g, b;
333   register JLONG *ctab = cconvert->rgb_y_tab;
334   register JSAMPROW outptr;
335   register JSAMPROW inptr0, inptr1, inptr2;
336   register JDIMENSION col;
337   JDIMENSION num_cols = cinfo->output_width;
338 
339   while (--num_rows >= 0) {
340     inptr0 = input_buf[0][input_row];
341     inptr1 = input_buf[1][input_row];
342     inptr2 = input_buf[2][input_row];
343     input_row++;
344     outptr = *output_buf++;
345     for (col = 0; col < num_cols; col++) {
346       r = GETJSAMPLE(inptr0[col]);
347       g = GETJSAMPLE(inptr1[col]);
348       b = GETJSAMPLE(inptr2[col]);
349       /* Y */
350       outptr[col] = (JSAMPLE)
351                 ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])
352                  >> SCALEBITS);
353     }
354   }
355 }
356 
357 
358 /*
359  * Color conversion for no colorspace change: just copy the data,
360  * converting from separate-planes to interleaved representation.
361  */
362 
363 METHODDEF(void)
null_convert(j_decompress_ptr cinfo,JSAMPIMAGE input_buf,JDIMENSION input_row,JSAMPARRAY output_buf,int num_rows)364 null_convert (j_decompress_ptr cinfo,
365               JSAMPIMAGE input_buf, JDIMENSION input_row,
366               JSAMPARRAY output_buf, int num_rows)
367 {
368   register JSAMPROW inptr, inptr0, inptr1, inptr2, inptr3, outptr;
369   register JDIMENSION col;
370   register int num_components = cinfo->num_components;
371   JDIMENSION num_cols = cinfo->output_width;
372   int ci;
373 
374   if (num_components == 3) {
375     while (--num_rows >= 0) {
376       inptr0 = input_buf[0][input_row];
377       inptr1 = input_buf[1][input_row];
378       inptr2 = input_buf[2][input_row];
379       input_row++;
380       outptr = *output_buf++;
381       for (col = 0; col < num_cols; col++) {
382         *outptr++ = inptr0[col];
383         *outptr++ = inptr1[col];
384         *outptr++ = inptr2[col];
385       }
386     }
387   } else if (num_components == 4) {
388     while (--num_rows >= 0) {
389       inptr0 = input_buf[0][input_row];
390       inptr1 = input_buf[1][input_row];
391       inptr2 = input_buf[2][input_row];
392       inptr3 = input_buf[3][input_row];
393       input_row++;
394       outptr = *output_buf++;
395       for (col = 0; col < num_cols; col++) {
396         *outptr++ = inptr0[col];
397         *outptr++ = inptr1[col];
398         *outptr++ = inptr2[col];
399         *outptr++ = inptr3[col];
400       }
401     }
402   } else {
403     while (--num_rows >= 0) {
404       for (ci = 0; ci < num_components; ci++) {
405         inptr = input_buf[ci][input_row];
406         outptr = *output_buf;
407         for (col = 0; col < num_cols; col++) {
408           outptr[ci] = inptr[col];
409           outptr += num_components;
410         }
411       }
412       output_buf++;
413       input_row++;
414     }
415   }
416 }
417 
418 
419 /*
420  * Color conversion for grayscale: just copy the data.
421  * This also works for YCbCr -> grayscale conversion, in which
422  * we just copy the Y (luminance) component and ignore chrominance.
423  */
424 
425 METHODDEF(void)
grayscale_convert(j_decompress_ptr cinfo,JSAMPIMAGE input_buf,JDIMENSION input_row,JSAMPARRAY output_buf,int num_rows)426 grayscale_convert (j_decompress_ptr cinfo,
427                    JSAMPIMAGE input_buf, JDIMENSION input_row,
428                    JSAMPARRAY output_buf, int num_rows)
429 {
430   jcopy_sample_rows(input_buf[0], (int) input_row, output_buf, 0,
431                     num_rows, cinfo->output_width);
432 }
433 
434 
435 /*
436  * Convert grayscale to RGB
437  */
438 
439 METHODDEF(void)
gray_rgb_convert(j_decompress_ptr cinfo,JSAMPIMAGE input_buf,JDIMENSION input_row,JSAMPARRAY output_buf,int num_rows)440 gray_rgb_convert (j_decompress_ptr cinfo,
441                   JSAMPIMAGE input_buf, JDIMENSION input_row,
442                   JSAMPARRAY output_buf, int num_rows)
443 {
444   switch (cinfo->out_color_space) {
445     case JCS_EXT_RGB:
446       gray_extrgb_convert_internal(cinfo, input_buf, input_row, output_buf,
447                                    num_rows);
448       break;
449     case JCS_EXT_RGBX:
450     case JCS_EXT_RGBA:
451       gray_extrgbx_convert_internal(cinfo, input_buf, input_row, output_buf,
452                                     num_rows);
453       break;
454     case JCS_EXT_BGR:
455       gray_extbgr_convert_internal(cinfo, input_buf, input_row, output_buf,
456                                    num_rows);
457       break;
458     case JCS_EXT_BGRX:
459     case JCS_EXT_BGRA:
460       gray_extbgrx_convert_internal(cinfo, input_buf, input_row, output_buf,
461                                     num_rows);
462       break;
463     case JCS_EXT_XBGR:
464     case JCS_EXT_ABGR:
465       gray_extxbgr_convert_internal(cinfo, input_buf, input_row, output_buf,
466                                     num_rows);
467       break;
468     case JCS_EXT_XRGB:
469     case JCS_EXT_ARGB:
470       gray_extxrgb_convert_internal(cinfo, input_buf, input_row, output_buf,
471                                     num_rows);
472       break;
473     default:
474       gray_rgb_convert_internal(cinfo, input_buf, input_row, output_buf,
475                                 num_rows);
476       break;
477   }
478 }
479 
480 
481 /*
482  * Convert plain RGB to extended RGB
483  */
484 
485 METHODDEF(void)
rgb_rgb_convert(j_decompress_ptr cinfo,JSAMPIMAGE input_buf,JDIMENSION input_row,JSAMPARRAY output_buf,int num_rows)486 rgb_rgb_convert (j_decompress_ptr cinfo,
487                   JSAMPIMAGE input_buf, JDIMENSION input_row,
488                   JSAMPARRAY output_buf, int num_rows)
489 {
490   switch (cinfo->out_color_space) {
491     case JCS_EXT_RGB:
492       rgb_extrgb_convert_internal(cinfo, input_buf, input_row, output_buf,
493                                   num_rows);
494       break;
495     case JCS_EXT_RGBX:
496     case JCS_EXT_RGBA:
497       rgb_extrgbx_convert_internal(cinfo, input_buf, input_row, output_buf,
498                                    num_rows);
499       break;
500     case JCS_EXT_BGR:
501       rgb_extbgr_convert_internal(cinfo, input_buf, input_row, output_buf,
502                                   num_rows);
503       break;
504     case JCS_EXT_BGRX:
505     case JCS_EXT_BGRA:
506       rgb_extbgrx_convert_internal(cinfo, input_buf, input_row, output_buf,
507                                    num_rows);
508       break;
509     case JCS_EXT_XBGR:
510     case JCS_EXT_ABGR:
511       rgb_extxbgr_convert_internal(cinfo, input_buf, input_row, output_buf,
512                                    num_rows);
513       break;
514     case JCS_EXT_XRGB:
515     case JCS_EXT_ARGB:
516       rgb_extxrgb_convert_internal(cinfo, input_buf, input_row, output_buf,
517                                    num_rows);
518       break;
519     default:
520       rgb_rgb_convert_internal(cinfo, input_buf, input_row, output_buf,
521                                num_rows);
522       break;
523   }
524 }
525 
526 
527 /*
528  * Adobe-style YCCK->CMYK conversion.
529  * We convert YCbCr to R=1-C, G=1-M, and B=1-Y using the same
530  * conversion as above, while passing K (black) unchanged.
531  * We assume build_ycc_rgb_table has been called.
532  */
533 
534 METHODDEF(void)
ycck_cmyk_convert(j_decompress_ptr cinfo,JSAMPIMAGE input_buf,JDIMENSION input_row,JSAMPARRAY output_buf,int num_rows)535 ycck_cmyk_convert (j_decompress_ptr cinfo,
536                    JSAMPIMAGE input_buf, JDIMENSION input_row,
537                    JSAMPARRAY output_buf, int num_rows)
538 {
539   my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
540   register int y, cb, cr;
541   register JSAMPROW outptr;
542   register JSAMPROW inptr0, inptr1, inptr2, inptr3;
543   register JDIMENSION col;
544   JDIMENSION num_cols = cinfo->output_width;
545   /* copy these pointers into registers if possible */
546   register JSAMPLE *range_limit = cinfo->sample_range_limit;
547   register int *Crrtab = cconvert->Cr_r_tab;
548   register int *Cbbtab = cconvert->Cb_b_tab;
549   register JLONG *Crgtab = cconvert->Cr_g_tab;
550   register JLONG *Cbgtab = cconvert->Cb_g_tab;
551   SHIFT_TEMPS
552 
553   while (--num_rows >= 0) {
554     inptr0 = input_buf[0][input_row];
555     inptr1 = input_buf[1][input_row];
556     inptr2 = input_buf[2][input_row];
557     inptr3 = input_buf[3][input_row];
558     input_row++;
559     outptr = *output_buf++;
560     for (col = 0; col < num_cols; col++) {
561       y  = GETJSAMPLE(inptr0[col]);
562       cb = GETJSAMPLE(inptr1[col]);
563       cr = GETJSAMPLE(inptr2[col]);
564       /* Range-limiting is essential due to noise introduced by DCT losses. */
565       outptr[0] = range_limit[MAXJSAMPLE - (y + Crrtab[cr])];   /* red */
566       outptr[1] = range_limit[MAXJSAMPLE - (y +                 /* green */
567                               ((int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr],
568                                                  SCALEBITS)))];
569       outptr[2] = range_limit[MAXJSAMPLE - (y + Cbbtab[cb])];   /* blue */
570       /* K passes through unchanged */
571       outptr[3] = inptr3[col];  /* don't need GETJSAMPLE here */
572       outptr += 4;
573     }
574   }
575 }
576 
577 
578 /*
579  * RGB565 conversion
580  */
581 
582 #define PACK_SHORT_565_LE(r, g, b)   ((((r) << 8) & 0xF800) |  \
583                                       (((g) << 3) & 0x7E0) | ((b) >> 3))
584 #define PACK_SHORT_565_BE(r, g, b)   (((r) & 0xF8) | ((g) >> 5) |  \
585                                       (((g) << 11) & 0xE000) |  \
586                                       (((b) << 5) & 0x1F00))
587 
588 #define PACK_TWO_PIXELS_LE(l, r)     ((r << 16) | l)
589 #define PACK_TWO_PIXELS_BE(l, r)     ((l << 16) | r)
590 
591 #define PACK_NEED_ALIGNMENT(ptr)     (((size_t)(ptr)) & 3)
592 
593 #define WRITE_TWO_ALIGNED_PIXELS(addr, pixels)  ((*(int *)(addr)) = pixels)
594 
595 #define DITHER_565_R(r, dither)  ((r) + ((dither) & 0xFF))
596 #define DITHER_565_G(g, dither)  ((g) + (((dither) & 0xFF) >> 1))
597 #define DITHER_565_B(b, dither)  ((b) + ((dither) & 0xFF))
598 
599 
600 /* Declarations for ordered dithering
601  *
602  * We use a 4x4 ordered dither array packed into 32 bits.  This array is
603  * sufficent for dithering RGB888 to RGB565.
604  */
605 
606 #define DITHER_MASK       0x3
607 #define DITHER_ROTATE(x)  ((((x) & 0xFF) << 24) | (((x) >> 8) & 0x00FFFFFF))
608 static const JLONG dither_matrix[4] = {
609   0x0008020A,
610   0x0C040E06,
611   0x030B0109,
612   0x0F070D05
613 };
614 
615 
is_big_endian(void)616 static INLINE boolean is_big_endian(void)
617 {
618   int test_value = 1;
619   if(*(char *)&test_value != 1)
620     return TRUE;
621   return FALSE;
622 }
623 
624 
625 /* Include inline routines for RGB565 conversion */
626 
627 #define PACK_SHORT_565 PACK_SHORT_565_LE
628 #define PACK_TWO_PIXELS PACK_TWO_PIXELS_LE
629 #define ycc_rgb565_convert_internal ycc_rgb565_convert_le
630 #define ycc_rgb565D_convert_internal ycc_rgb565D_convert_le
631 #define rgb_rgb565_convert_internal rgb_rgb565_convert_le
632 #define rgb_rgb565D_convert_internal rgb_rgb565D_convert_le
633 #define gray_rgb565_convert_internal gray_rgb565_convert_le
634 #define gray_rgb565D_convert_internal gray_rgb565D_convert_le
635 #include "jdcol565.c"
636 #undef PACK_SHORT_565
637 #undef PACK_TWO_PIXELS
638 #undef ycc_rgb565_convert_internal
639 #undef ycc_rgb565D_convert_internal
640 #undef rgb_rgb565_convert_internal
641 #undef rgb_rgb565D_convert_internal
642 #undef gray_rgb565_convert_internal
643 #undef gray_rgb565D_convert_internal
644 
645 #define PACK_SHORT_565 PACK_SHORT_565_BE
646 #define PACK_TWO_PIXELS PACK_TWO_PIXELS_BE
647 #define ycc_rgb565_convert_internal ycc_rgb565_convert_be
648 #define ycc_rgb565D_convert_internal ycc_rgb565D_convert_be
649 #define rgb_rgb565_convert_internal rgb_rgb565_convert_be
650 #define rgb_rgb565D_convert_internal rgb_rgb565D_convert_be
651 #define gray_rgb565_convert_internal gray_rgb565_convert_be
652 #define gray_rgb565D_convert_internal gray_rgb565D_convert_be
653 #include "jdcol565.c"
654 #undef PACK_SHORT_565
655 #undef PACK_TWO_PIXELS
656 #undef ycc_rgb565_convert_internal
657 #undef ycc_rgb565D_convert_internal
658 #undef rgb_rgb565_convert_internal
659 #undef rgb_rgb565D_convert_internal
660 #undef gray_rgb565_convert_internal
661 #undef gray_rgb565D_convert_internal
662 
663 
664 METHODDEF(void)
ycc_rgb565_convert(j_decompress_ptr cinfo,JSAMPIMAGE input_buf,JDIMENSION input_row,JSAMPARRAY output_buf,int num_rows)665 ycc_rgb565_convert (j_decompress_ptr cinfo,
666                     JSAMPIMAGE input_buf, JDIMENSION input_row,
667                     JSAMPARRAY output_buf, int num_rows)
668 {
669   if (is_big_endian())
670     ycc_rgb565_convert_be(cinfo, input_buf, input_row, output_buf, num_rows);
671   else
672     ycc_rgb565_convert_le(cinfo, input_buf, input_row, output_buf, num_rows);
673 }
674 
675 
676 METHODDEF(void)
ycc_rgb565D_convert(j_decompress_ptr cinfo,JSAMPIMAGE input_buf,JDIMENSION input_row,JSAMPARRAY output_buf,int num_rows)677 ycc_rgb565D_convert (j_decompress_ptr cinfo,
678                      JSAMPIMAGE input_buf, JDIMENSION input_row,
679                      JSAMPARRAY output_buf, int num_rows)
680 {
681   if (is_big_endian())
682     ycc_rgb565D_convert_be(cinfo, input_buf, input_row, output_buf, num_rows);
683   else
684     ycc_rgb565D_convert_le(cinfo, input_buf, input_row, output_buf, num_rows);
685 }
686 
687 
688 METHODDEF(void)
rgb_rgb565_convert(j_decompress_ptr cinfo,JSAMPIMAGE input_buf,JDIMENSION input_row,JSAMPARRAY output_buf,int num_rows)689 rgb_rgb565_convert (j_decompress_ptr cinfo,
690                     JSAMPIMAGE input_buf, JDIMENSION input_row,
691                     JSAMPARRAY output_buf, int num_rows)
692 {
693   if (is_big_endian())
694     rgb_rgb565_convert_be(cinfo, input_buf, input_row, output_buf, num_rows);
695   else
696     rgb_rgb565_convert_le(cinfo, input_buf, input_row, output_buf, num_rows);
697 }
698 
699 
700 METHODDEF(void)
rgb_rgb565D_convert(j_decompress_ptr cinfo,JSAMPIMAGE input_buf,JDIMENSION input_row,JSAMPARRAY output_buf,int num_rows)701 rgb_rgb565D_convert (j_decompress_ptr cinfo,
702                      JSAMPIMAGE input_buf, JDIMENSION input_row,
703                      JSAMPARRAY output_buf, int num_rows)
704 {
705   if (is_big_endian())
706     rgb_rgb565D_convert_be(cinfo, input_buf, input_row, output_buf, num_rows);
707   else
708     rgb_rgb565D_convert_le(cinfo, input_buf, input_row, output_buf, num_rows);
709 }
710 
711 
712 METHODDEF(void)
gray_rgb565_convert(j_decompress_ptr cinfo,JSAMPIMAGE input_buf,JDIMENSION input_row,JSAMPARRAY output_buf,int num_rows)713 gray_rgb565_convert (j_decompress_ptr cinfo,
714                      JSAMPIMAGE input_buf, JDIMENSION input_row,
715                      JSAMPARRAY output_buf, int num_rows)
716 {
717   if (is_big_endian())
718     gray_rgb565_convert_be(cinfo, input_buf, input_row, output_buf, num_rows);
719   else
720     gray_rgb565_convert_le(cinfo, input_buf, input_row, output_buf, num_rows);
721 }
722 
723 
724 METHODDEF(void)
gray_rgb565D_convert(j_decompress_ptr cinfo,JSAMPIMAGE input_buf,JDIMENSION input_row,JSAMPARRAY output_buf,int num_rows)725 gray_rgb565D_convert (j_decompress_ptr cinfo,
726                       JSAMPIMAGE input_buf, JDIMENSION input_row,
727                       JSAMPARRAY output_buf, int num_rows)
728 {
729   if (is_big_endian())
730     gray_rgb565D_convert_be(cinfo, input_buf, input_row, output_buf, num_rows);
731   else
732     gray_rgb565D_convert_le(cinfo, input_buf, input_row, output_buf, num_rows);
733 }
734 
735 
736 /*
737  * Empty method for start_pass.
738  */
739 
740 METHODDEF(void)
start_pass_dcolor(j_decompress_ptr cinfo)741 start_pass_dcolor (j_decompress_ptr cinfo)
742 {
743   /* no work needed */
744 }
745 
746 
747 /*
748  * Module initialization routine for output colorspace conversion.
749  */
750 
751 GLOBAL(void)
jinit_color_deconverter(j_decompress_ptr cinfo)752 jinit_color_deconverter (j_decompress_ptr cinfo)
753 {
754   my_cconvert_ptr cconvert;
755   int ci;
756 
757   cconvert = (my_cconvert_ptr)
758     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
759                                 sizeof(my_color_deconverter));
760   cinfo->cconvert = (struct jpeg_color_deconverter *) cconvert;
761   cconvert->pub.start_pass = start_pass_dcolor;
762 
763   /* Make sure num_components agrees with jpeg_color_space */
764   switch (cinfo->jpeg_color_space) {
765   case JCS_GRAYSCALE:
766     if (cinfo->num_components != 1)
767       ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
768     break;
769 
770   case JCS_RGB:
771   case JCS_YCbCr:
772     if (cinfo->num_components != 3)
773       ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
774     break;
775 
776   case JCS_CMYK:
777   case JCS_YCCK:
778     if (cinfo->num_components != 4)
779       ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
780     break;
781 
782   default:                      /* JCS_UNKNOWN can be anything */
783     if (cinfo->num_components < 1)
784       ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
785     break;
786   }
787 
788   /* Set out_color_components and conversion method based on requested space.
789    * Also clear the component_needed flags for any unused components,
790    * so that earlier pipeline stages can avoid useless computation.
791    */
792 
793   switch (cinfo->out_color_space) {
794   case JCS_GRAYSCALE:
795     cinfo->out_color_components = 1;
796     if (cinfo->jpeg_color_space == JCS_GRAYSCALE ||
797         cinfo->jpeg_color_space == JCS_YCbCr) {
798       cconvert->pub.color_convert = grayscale_convert;
799       /* For color->grayscale conversion, only the Y (0) component is needed */
800       for (ci = 1; ci < cinfo->num_components; ci++)
801         cinfo->comp_info[ci].component_needed = FALSE;
802     } else if (cinfo->jpeg_color_space == JCS_RGB) {
803       cconvert->pub.color_convert = rgb_gray_convert;
804       build_rgb_y_table(cinfo);
805     } else
806       ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
807     break;
808 
809   case JCS_RGB:
810   case JCS_EXT_RGB:
811   case JCS_EXT_RGBX:
812   case JCS_EXT_BGR:
813   case JCS_EXT_BGRX:
814   case JCS_EXT_XBGR:
815   case JCS_EXT_XRGB:
816   case JCS_EXT_RGBA:
817   case JCS_EXT_BGRA:
818   case JCS_EXT_ABGR:
819   case JCS_EXT_ARGB:
820     cinfo->out_color_components = rgb_pixelsize[cinfo->out_color_space];
821     if (cinfo->jpeg_color_space == JCS_YCbCr) {
822       if (jsimd_can_ycc_rgb())
823         cconvert->pub.color_convert = jsimd_ycc_rgb_convert;
824       else {
825         cconvert->pub.color_convert = ycc_rgb_convert;
826         build_ycc_rgb_table(cinfo);
827       }
828     } else if (cinfo->jpeg_color_space == JCS_GRAYSCALE) {
829       cconvert->pub.color_convert = gray_rgb_convert;
830     } else if (cinfo->jpeg_color_space == JCS_RGB) {
831       if (rgb_red[cinfo->out_color_space] == 0 &&
832           rgb_green[cinfo->out_color_space] == 1 &&
833           rgb_blue[cinfo->out_color_space] == 2 &&
834           rgb_pixelsize[cinfo->out_color_space] == 3)
835         cconvert->pub.color_convert = null_convert;
836       else
837         cconvert->pub.color_convert = rgb_rgb_convert;
838     } else
839       ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
840     break;
841 
842   case JCS_RGB565:
843     cinfo->out_color_components = 3;
844     if (cinfo->dither_mode == JDITHER_NONE) {
845       if (cinfo->jpeg_color_space == JCS_YCbCr) {
846          if (jsimd_can_ycc_rgb565())
847            cconvert->pub.color_convert = jsimd_ycc_rgb565_convert;
848          else {
849            cconvert->pub.color_convert = ycc_rgb565_convert;
850            build_ycc_rgb_table(cinfo);
851         }
852       } else if (cinfo->jpeg_color_space == JCS_GRAYSCALE) {
853         cconvert->pub.color_convert = gray_rgb565_convert;
854       } else if (cinfo->jpeg_color_space == JCS_RGB) {
855         cconvert->pub.color_convert = rgb_rgb565_convert;
856       } else
857         ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
858     } else {
859       /* only ordered dithering is supported */
860       if (cinfo->jpeg_color_space == JCS_YCbCr) {
861         cconvert->pub.color_convert = ycc_rgb565D_convert;
862         build_ycc_rgb_table(cinfo);
863       } else if (cinfo->jpeg_color_space == JCS_GRAYSCALE) {
864         cconvert->pub.color_convert = gray_rgb565D_convert;
865       } else if (cinfo->jpeg_color_space == JCS_RGB) {
866         cconvert->pub.color_convert = rgb_rgb565D_convert;
867       } else
868         ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
869     }
870     break;
871 
872   case JCS_CMYK:
873     cinfo->out_color_components = 4;
874     if (cinfo->jpeg_color_space == JCS_YCCK) {
875       cconvert->pub.color_convert = ycck_cmyk_convert;
876       build_ycc_rgb_table(cinfo);
877     } else if (cinfo->jpeg_color_space == JCS_CMYK) {
878       cconvert->pub.color_convert = null_convert;
879     } else
880       ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
881     break;
882 
883   default:
884     /* Permit null conversion to same output space */
885     if (cinfo->out_color_space == cinfo->jpeg_color_space) {
886       cinfo->out_color_components = cinfo->num_components;
887       cconvert->pub.color_convert = null_convert;
888     } else                      /* unsupported non-null conversion */
889       ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
890     break;
891   }
892 
893   if (cinfo->quantize_colors)
894     cinfo->output_components = 1; /* single colormapped output component */
895   else
896     cinfo->output_components = cinfo->out_color_components;
897 }
898