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
26typedef 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
39typedef 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
210LOCAL(void)
211build_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
253METHODDEF(void)
254ycc_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
302LOCAL(void)
303build_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
326METHODDEF(void)
327rgb_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
363METHODDEF(void)
364null_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
425METHODDEF(void)
426grayscale_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
439METHODDEF(void)
440gray_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
485METHODDEF(void)
486rgb_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
534METHODDEF(void)
535ycck_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))
608static const JLONG dither_matrix[4] = {
609  0x0008020A,
610  0x0C040E06,
611  0x030B0109,
612  0x0F070D05
613};
614
615
616static 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
664METHODDEF(void)
665ycc_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
676METHODDEF(void)
677ycc_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
688METHODDEF(void)
689rgb_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
700METHODDEF(void)
701rgb_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
712METHODDEF(void)
713gray_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
724METHODDEF(void)
725gray_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
740METHODDEF(void)
741start_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
751GLOBAL(void)
752jinit_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