4 * This file was part of the Independent JPEG Group's software:
5 * Copyright (C) 1991-1996, Thomas G. Lane.
6 * libjpeg-turbo Modifications:
7 * Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
8 * Copyright (C) 2009-2012, 2015, D. R. Commander.
9 * Copyright (C) 2014, MIPS Technologies, Inc., California.
10 * For conditions of distribution and use, see the accompanying README.ijg
13 * This file contains input colorspace conversion routines.
16 #define JPEG_INTERNALS
20 #include "jconfigint.h"
23 /* Private subobject */
26 struct jpeg_color_converter pub; /* public fields */
28 /* Private state for RGB->YCC conversion */
29 JLONG *rgb_ycc_tab; /* => table for RGB to YCbCr conversion */
32 typedef my_color_converter *my_cconvert_ptr;
35 /**************** RGB -> YCbCr conversion: most common case **************/
38 * YCbCr is defined per CCIR 601-1, except that Cb and Cr are
39 * normalized to the range 0..MAXJSAMPLE rather than -0.5 .. 0.5.
40 * The conversion equations to be implemented are therefore
41 * Y = 0.29900 * R + 0.58700 * G + 0.11400 * B
42 * Cb = -0.16874 * R - 0.33126 * G + 0.50000 * B + CENTERJSAMPLE
43 * Cr = 0.50000 * R - 0.41869 * G - 0.08131 * B + CENTERJSAMPLE
44 * (These numbers are derived from TIFF 6.0 section 21, dated 3-June-92.)
45 * Note: older versions of the IJG code used a zero offset of MAXJSAMPLE/2,
46 * rather than CENTERJSAMPLE, for Cb and Cr. This gave equal positive and
47 * negative swings for Cb/Cr, but meant that grayscale values (Cb=Cr=0)
48 * were not represented exactly. Now we sacrifice exact representation of
49 * maximum red and maximum blue in order to get exact grayscales.
51 * To avoid floating-point arithmetic, we represent the fractional constants
52 * as integers scaled up by 2^16 (about 4 digits precision); we have to divide
53 * the products by 2^16, with appropriate rounding, to get the correct answer.
55 * For even more speed, we avoid doing any multiplications in the inner loop
56 * by precalculating the constants times R,G,B for all possible values.
57 * For 8-bit JSAMPLEs this is very reasonable (only 256 entries per table);
58 * for 12-bit samples it is still acceptable. It's not very reasonable for
59 * 16-bit samples, but if you want lossless storage you shouldn't be changing
61 * The CENTERJSAMPLE offsets and the rounding fudge-factor of 0.5 are included
62 * in the tables to save adding them separately in the inner loop.
65 #define SCALEBITS 16 /* speediest right-shift on some machines */
66 #define CBCR_OFFSET ((JLONG) CENTERJSAMPLE << SCALEBITS)
67 #define ONE_HALF ((JLONG) 1 << (SCALEBITS-1))
68 #define FIX(x) ((JLONG) ((x) * (1L<<SCALEBITS) + 0.5))
70 /* We allocate one big table and divide it up into eight parts, instead of
71 * doing eight alloc_small requests. This lets us use a single table base
72 * address, which can be held in a register in the inner loops on many
73 * machines (more than can hold all eight addresses, anyway).
76 #define R_Y_OFF 0 /* offset to R => Y section */
77 #define G_Y_OFF (1*(MAXJSAMPLE+1)) /* offset to G => Y section */
78 #define B_Y_OFF (2*(MAXJSAMPLE+1)) /* etc. */
79 #define R_CB_OFF (3*(MAXJSAMPLE+1))
80 #define G_CB_OFF (4*(MAXJSAMPLE+1))
81 #define B_CB_OFF (5*(MAXJSAMPLE+1))
82 #define R_CR_OFF B_CB_OFF /* B=>Cb, R=>Cr are the same */
83 #define G_CR_OFF (6*(MAXJSAMPLE+1))
84 #define B_CR_OFF (7*(MAXJSAMPLE+1))
85 #define TABLE_SIZE (8*(MAXJSAMPLE+1))
88 /* Include inline routines for colorspace extensions */
96 #define RGB_RED EXT_RGB_RED
97 #define RGB_GREEN EXT_RGB_GREEN
98 #define RGB_BLUE EXT_RGB_BLUE
99 #define RGB_PIXELSIZE EXT_RGB_PIXELSIZE
100 #define rgb_ycc_convert_internal extrgb_ycc_convert_internal
101 #define rgb_gray_convert_internal extrgb_gray_convert_internal
102 #define rgb_rgb_convert_internal extrgb_rgb_convert_internal
103 #include "jccolext.c"
108 #undef rgb_ycc_convert_internal
109 #undef rgb_gray_convert_internal
110 #undef rgb_rgb_convert_internal
112 #define RGB_RED EXT_RGBX_RED
113 #define RGB_GREEN EXT_RGBX_GREEN
114 #define RGB_BLUE EXT_RGBX_BLUE
115 #define RGB_PIXELSIZE EXT_RGBX_PIXELSIZE
116 #define rgb_ycc_convert_internal extrgbx_ycc_convert_internal
117 #define rgb_gray_convert_internal extrgbx_gray_convert_internal
118 #define rgb_rgb_convert_internal extrgbx_rgb_convert_internal
119 #include "jccolext.c"
124 #undef rgb_ycc_convert_internal
125 #undef rgb_gray_convert_internal
126 #undef rgb_rgb_convert_internal
128 #define RGB_RED EXT_BGR_RED
129 #define RGB_GREEN EXT_BGR_GREEN
130 #define RGB_BLUE EXT_BGR_BLUE
131 #define RGB_PIXELSIZE EXT_BGR_PIXELSIZE
132 #define rgb_ycc_convert_internal extbgr_ycc_convert_internal
133 #define rgb_gray_convert_internal extbgr_gray_convert_internal
134 #define rgb_rgb_convert_internal extbgr_rgb_convert_internal
135 #include "jccolext.c"
140 #undef rgb_ycc_convert_internal
141 #undef rgb_gray_convert_internal
142 #undef rgb_rgb_convert_internal
144 #define RGB_RED EXT_BGRX_RED
145 #define RGB_GREEN EXT_BGRX_GREEN
146 #define RGB_BLUE EXT_BGRX_BLUE
147 #define RGB_PIXELSIZE EXT_BGRX_PIXELSIZE
148 #define rgb_ycc_convert_internal extbgrx_ycc_convert_internal
149 #define rgb_gray_convert_internal extbgrx_gray_convert_internal
150 #define rgb_rgb_convert_internal extbgrx_rgb_convert_internal
151 #include "jccolext.c"
156 #undef rgb_ycc_convert_internal
157 #undef rgb_gray_convert_internal
158 #undef rgb_rgb_convert_internal
160 #define RGB_RED EXT_XBGR_RED
161 #define RGB_GREEN EXT_XBGR_GREEN
162 #define RGB_BLUE EXT_XBGR_BLUE
163 #define RGB_PIXELSIZE EXT_XBGR_PIXELSIZE
164 #define rgb_ycc_convert_internal extxbgr_ycc_convert_internal
165 #define rgb_gray_convert_internal extxbgr_gray_convert_internal
166 #define rgb_rgb_convert_internal extxbgr_rgb_convert_internal
167 #include "jccolext.c"
172 #undef rgb_ycc_convert_internal
173 #undef rgb_gray_convert_internal
174 #undef rgb_rgb_convert_internal
176 #define RGB_RED EXT_XRGB_RED
177 #define RGB_GREEN EXT_XRGB_GREEN
178 #define RGB_BLUE EXT_XRGB_BLUE
179 #define RGB_PIXELSIZE EXT_XRGB_PIXELSIZE
180 #define rgb_ycc_convert_internal extxrgb_ycc_convert_internal
181 #define rgb_gray_convert_internal extxrgb_gray_convert_internal
182 #define rgb_rgb_convert_internal extxrgb_rgb_convert_internal
183 #include "jccolext.c"
188 #undef rgb_ycc_convert_internal
189 #undef rgb_gray_convert_internal
190 #undef rgb_rgb_convert_internal
194 * Initialize for RGB->YCC colorspace conversion.
198 rgb_ycc_start (j_compress_ptr cinfo)
200 my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
204 /* Allocate and fill in the conversion tables. */
205 cconvert->rgb_ycc_tab = rgb_ycc_tab = (JLONG *)
206 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
207 (TABLE_SIZE * sizeof(JLONG)));
209 for (i = 0; i <= MAXJSAMPLE; i++) {
210 rgb_ycc_tab[i+R_Y_OFF] = FIX(0.29900) * i;
211 rgb_ycc_tab[i+G_Y_OFF] = FIX(0.58700) * i;
212 rgb_ycc_tab[i+B_Y_OFF] = FIX(0.11400) * i + ONE_HALF;
213 rgb_ycc_tab[i+R_CB_OFF] = (-FIX(0.16874)) * i;
214 rgb_ycc_tab[i+G_CB_OFF] = (-FIX(0.33126)) * i;
215 /* We use a rounding fudge-factor of 0.5-epsilon for Cb and Cr.
216 * This ensures that the maximum output will round to MAXJSAMPLE
217 * not MAXJSAMPLE+1, and thus that we don't have to range-limit.
219 rgb_ycc_tab[i+B_CB_OFF] = FIX(0.50000) * i + CBCR_OFFSET + ONE_HALF-1;
220 /* B=>Cb and R=>Cr tables are the same
221 rgb_ycc_tab[i+R_CR_OFF] = FIX(0.50000) * i + CBCR_OFFSET + ONE_HALF-1;
223 rgb_ycc_tab[i+G_CR_OFF] = (-FIX(0.41869)) * i;
224 rgb_ycc_tab[i+B_CR_OFF] = (-FIX(0.08131)) * i;
230 * Convert some rows of samples to the JPEG colorspace.
234 rgb_ycc_convert (j_compress_ptr cinfo,
235 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
236 JDIMENSION output_row, int num_rows)
238 switch (cinfo->in_color_space) {
240 extrgb_ycc_convert_internal(cinfo, input_buf, output_buf, output_row,
245 extrgbx_ycc_convert_internal(cinfo, input_buf, output_buf, output_row,
249 extbgr_ycc_convert_internal(cinfo, input_buf, output_buf, output_row,
254 extbgrx_ycc_convert_internal(cinfo, input_buf, output_buf, output_row,
259 extxbgr_ycc_convert_internal(cinfo, input_buf, output_buf, output_row,
264 extxrgb_ycc_convert_internal(cinfo, input_buf, output_buf, output_row,
268 rgb_ycc_convert_internal(cinfo, input_buf, output_buf, output_row,
275 /**************** Cases other than RGB -> YCbCr **************/
279 * Convert some rows of samples to the JPEG colorspace.
283 rgb_gray_convert (j_compress_ptr cinfo,
284 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
285 JDIMENSION output_row, int num_rows)
287 switch (cinfo->in_color_space) {
289 extrgb_gray_convert_internal(cinfo, input_buf, output_buf, output_row,
294 extrgbx_gray_convert_internal(cinfo, input_buf, output_buf, output_row,
298 extbgr_gray_convert_internal(cinfo, input_buf, output_buf, output_row,
303 extbgrx_gray_convert_internal(cinfo, input_buf, output_buf, output_row,
308 extxbgr_gray_convert_internal(cinfo, input_buf, output_buf, output_row,
313 extxrgb_gray_convert_internal(cinfo, input_buf, output_buf, output_row,
317 rgb_gray_convert_internal(cinfo, input_buf, output_buf, output_row,
325 * Extended RGB to plain RGB conversion
329 rgb_rgb_convert (j_compress_ptr cinfo,
330 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
331 JDIMENSION output_row, int num_rows)
333 switch (cinfo->in_color_space) {
335 extrgb_rgb_convert_internal(cinfo, input_buf, output_buf, output_row,
340 extrgbx_rgb_convert_internal(cinfo, input_buf, output_buf, output_row,
344 extbgr_rgb_convert_internal(cinfo, input_buf, output_buf, output_row,
349 extbgrx_rgb_convert_internal(cinfo, input_buf, output_buf, output_row,
354 extxbgr_rgb_convert_internal(cinfo, input_buf, output_buf, output_row,
359 extxrgb_rgb_convert_internal(cinfo, input_buf, output_buf, output_row,
363 rgb_rgb_convert_internal(cinfo, input_buf, output_buf, output_row,
371 * Convert some rows of samples to the JPEG colorspace.
372 * This version handles Adobe-style CMYK->YCCK conversion,
373 * where we convert R=1-C, G=1-M, and B=1-Y to YCbCr using the same
374 * conversion as above, while passing K (black) unchanged.
375 * We assume rgb_ycc_start has been called.
379 cmyk_ycck_convert (j_compress_ptr cinfo,
380 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
381 JDIMENSION output_row, int num_rows)
383 my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
384 register int r, g, b;
385 register JLONG *ctab = cconvert->rgb_ycc_tab;
386 register JSAMPROW inptr;
387 register JSAMPROW outptr0, outptr1, outptr2, outptr3;
388 register JDIMENSION col;
389 JDIMENSION num_cols = cinfo->image_width;
391 while (--num_rows >= 0) {
392 inptr = *input_buf++;
393 outptr0 = output_buf[0][output_row];
394 outptr1 = output_buf[1][output_row];
395 outptr2 = output_buf[2][output_row];
396 outptr3 = output_buf[3][output_row];
398 for (col = 0; col < num_cols; col++) {
399 r = MAXJSAMPLE - GETJSAMPLE(inptr[0]);
400 g = MAXJSAMPLE - GETJSAMPLE(inptr[1]);
401 b = MAXJSAMPLE - GETJSAMPLE(inptr[2]);
402 /* K passes through as-is */
403 outptr3[col] = inptr[3]; /* don't need GETJSAMPLE here */
405 /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations
406 * must be too; we do not need an explicit range-limiting operation.
407 * Hence the value being shifted is never negative, and we don't
408 * need the general RIGHT_SHIFT macro.
411 outptr0[col] = (JSAMPLE)
412 ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])
415 outptr1[col] = (JSAMPLE)
416 ((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF])
419 outptr2[col] = (JSAMPLE)
420 ((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF])
428 * Convert some rows of samples to the JPEG colorspace.
429 * This version handles grayscale output with no conversion.
430 * The source can be either plain grayscale or YCbCr (since Y == gray).
434 grayscale_convert (j_compress_ptr cinfo,
435 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
436 JDIMENSION output_row, int num_rows)
438 register JSAMPROW inptr;
439 register JSAMPROW outptr;
440 register JDIMENSION col;
441 JDIMENSION num_cols = cinfo->image_width;
442 int instride = cinfo->input_components;
444 while (--num_rows >= 0) {
445 inptr = *input_buf++;
446 outptr = output_buf[0][output_row];
448 for (col = 0; col < num_cols; col++) {
449 outptr[col] = inptr[0]; /* don't need GETJSAMPLE() here */
457 * Convert some rows of samples to the JPEG colorspace.
458 * This version handles multi-component colorspaces without conversion.
459 * We assume input_components == num_components.
463 null_convert (j_compress_ptr cinfo,
464 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
465 JDIMENSION output_row, int num_rows)
467 register JSAMPROW inptr;
468 register JSAMPROW outptr, outptr0, outptr1, outptr2, outptr3;
469 register JDIMENSION col;
471 int nc = cinfo->num_components;
472 JDIMENSION num_cols = cinfo->image_width;
475 while (--num_rows >= 0) {
476 inptr = *input_buf++;
477 outptr0 = output_buf[0][output_row];
478 outptr1 = output_buf[1][output_row];
479 outptr2 = output_buf[2][output_row];
481 for (col = 0; col < num_cols; col++) {
482 outptr0[col] = *inptr++;
483 outptr1[col] = *inptr++;
484 outptr2[col] = *inptr++;
487 } else if (nc == 4) {
488 while (--num_rows >= 0) {
489 inptr = *input_buf++;
490 outptr0 = output_buf[0][output_row];
491 outptr1 = output_buf[1][output_row];
492 outptr2 = output_buf[2][output_row];
493 outptr3 = output_buf[3][output_row];
495 for (col = 0; col < num_cols; col++) {
496 outptr0[col] = *inptr++;
497 outptr1[col] = *inptr++;
498 outptr2[col] = *inptr++;
499 outptr3[col] = *inptr++;
503 while (--num_rows >= 0) {
504 /* It seems fastest to make a separate pass for each component. */
505 for (ci = 0; ci < nc; ci++) {
507 outptr = output_buf[ci][output_row];
508 for (col = 0; col < num_cols; col++) {
509 outptr[col] = inptr[ci]; /* don't need GETJSAMPLE() here */
521 * Empty method for start_pass.
525 null_method (j_compress_ptr cinfo)
532 * Module initialization routine for input colorspace conversion.
536 jinit_color_converter (j_compress_ptr cinfo)
538 my_cconvert_ptr cconvert;
540 cconvert = (my_cconvert_ptr)
541 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
542 sizeof(my_color_converter));
543 cinfo->cconvert = (struct jpeg_color_converter *) cconvert;
544 /* set start_pass to null method until we find out differently */
545 cconvert->pub.start_pass = null_method;
547 /* Make sure input_components agrees with in_color_space */
548 switch (cinfo->in_color_space) {
550 if (cinfo->input_components != 1)
551 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
565 if (cinfo->input_components != rgb_pixelsize[cinfo->in_color_space])
566 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
570 if (cinfo->input_components != 3)
571 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
576 if (cinfo->input_components != 4)
577 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
580 default: /* JCS_UNKNOWN can be anything */
581 if (cinfo->input_components < 1)
582 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
586 /* Check num_components, set conversion method based on requested space */
587 switch (cinfo->jpeg_color_space) {
589 if (cinfo->num_components != 1)
590 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
591 if (cinfo->in_color_space == JCS_GRAYSCALE)
592 cconvert->pub.color_convert = grayscale_convert;
593 else if (cinfo->in_color_space == JCS_RGB ||
594 cinfo->in_color_space == JCS_EXT_RGB ||
595 cinfo->in_color_space == JCS_EXT_RGBX ||
596 cinfo->in_color_space == JCS_EXT_BGR ||
597 cinfo->in_color_space == JCS_EXT_BGRX ||
598 cinfo->in_color_space == JCS_EXT_XBGR ||
599 cinfo->in_color_space == JCS_EXT_XRGB ||
600 cinfo->in_color_space == JCS_EXT_RGBA ||
601 cinfo->in_color_space == JCS_EXT_BGRA ||
602 cinfo->in_color_space == JCS_EXT_ABGR ||
603 cinfo->in_color_space == JCS_EXT_ARGB) {
604 if (jsimd_can_rgb_gray())
605 cconvert->pub.color_convert = jsimd_rgb_gray_convert;
607 cconvert->pub.start_pass = rgb_ycc_start;
608 cconvert->pub.color_convert = rgb_gray_convert;
610 } else if (cinfo->in_color_space == JCS_YCbCr)
611 cconvert->pub.color_convert = grayscale_convert;
613 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
617 if (cinfo->num_components != 3)
618 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
619 if (rgb_red[cinfo->in_color_space] == 0 &&
620 rgb_green[cinfo->in_color_space] == 1 &&
621 rgb_blue[cinfo->in_color_space] == 2 &&
622 rgb_pixelsize[cinfo->in_color_space] == 3) {
623 #if defined(__mips__)
624 if (jsimd_c_can_null_convert())
625 cconvert->pub.color_convert = jsimd_c_null_convert;
628 cconvert->pub.color_convert = null_convert;
629 } else if (cinfo->in_color_space == JCS_RGB ||
630 cinfo->in_color_space == JCS_EXT_RGB ||
631 cinfo->in_color_space == JCS_EXT_RGBX ||
632 cinfo->in_color_space == JCS_EXT_BGR ||
633 cinfo->in_color_space == JCS_EXT_BGRX ||
634 cinfo->in_color_space == JCS_EXT_XBGR ||
635 cinfo->in_color_space == JCS_EXT_XRGB ||
636 cinfo->in_color_space == JCS_EXT_RGBA ||
637 cinfo->in_color_space == JCS_EXT_BGRA ||
638 cinfo->in_color_space == JCS_EXT_ABGR ||
639 cinfo->in_color_space == JCS_EXT_ARGB)
640 cconvert->pub.color_convert = rgb_rgb_convert;
642 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
646 if (cinfo->num_components != 3)
647 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
648 if (cinfo->in_color_space == JCS_RGB ||
649 cinfo->in_color_space == JCS_EXT_RGB ||
650 cinfo->in_color_space == JCS_EXT_RGBX ||
651 cinfo->in_color_space == JCS_EXT_BGR ||
652 cinfo->in_color_space == JCS_EXT_BGRX ||
653 cinfo->in_color_space == JCS_EXT_XBGR ||
654 cinfo->in_color_space == JCS_EXT_XRGB ||
655 cinfo->in_color_space == JCS_EXT_RGBA ||
656 cinfo->in_color_space == JCS_EXT_BGRA ||
657 cinfo->in_color_space == JCS_EXT_ABGR ||
658 cinfo->in_color_space == JCS_EXT_ARGB) {
659 if (jsimd_can_rgb_ycc())
660 cconvert->pub.color_convert = jsimd_rgb_ycc_convert;
662 cconvert->pub.start_pass = rgb_ycc_start;
663 cconvert->pub.color_convert = rgb_ycc_convert;
665 } else if (cinfo->in_color_space == JCS_YCbCr) {
666 #if defined(__mips__)
667 if (jsimd_c_can_null_convert())
668 cconvert->pub.color_convert = jsimd_c_null_convert;
671 cconvert->pub.color_convert = null_convert;
673 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
677 if (cinfo->num_components != 4)
678 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
679 if (cinfo->in_color_space == JCS_CMYK) {
680 #if defined(__mips__)
681 if (jsimd_c_can_null_convert())
682 cconvert->pub.color_convert = jsimd_c_null_convert;
685 cconvert->pub.color_convert = null_convert;
687 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
691 if (cinfo->num_components != 4)
692 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
693 if (cinfo->in_color_space == JCS_CMYK) {
694 cconvert->pub.start_pass = rgb_ycc_start;
695 cconvert->pub.color_convert = cmyk_ycck_convert;
696 } else if (cinfo->in_color_space == JCS_YCCK) {
697 #if defined(__mips__)
698 if (jsimd_c_can_null_convert())
699 cconvert->pub.color_convert = jsimd_c_null_convert;
702 cconvert->pub.color_convert = null_convert;
704 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
707 default: /* allow null conversion of JCS_UNKNOWN */
708 if (cinfo->jpeg_color_space != cinfo->in_color_space ||
709 cinfo->num_components != cinfo->input_components)
710 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
711 #if defined(__mips__)
712 if (jsimd_c_can_null_convert())
713 cconvert->pub.color_convert = jsimd_c_null_convert;
716 cconvert->pub.color_convert = null_convert;