Shoaib Ahmed / Mbed 2 deprecated uzairkhan

Final 350 project

Dependencies:   uzair Camera_LS_Y201 F7_Ethernet LCD_DISCO_F746NG NetworkAPI SDFileSystem mbed

includes/jccolor.c@0:791a779d6220, 2017-07-31 (annotated)

Committer:
shoaib_ahmed
Date:
Mon Jul 31 09:16:35 2017 +0000
Revision:
0:791a779d6220
final project;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
shoaib_ahmed 0:791a779d6220 1 /*
shoaib_ahmed 0:791a779d6220 2 * jccolor.c
shoaib_ahmed 0:791a779d6220 3 *
shoaib_ahmed 0:791a779d6220 4 * Copyright (C) 1991-1996, Thomas G. Lane.
shoaib_ahmed 0:791a779d6220 5 * Modified 2011-2013 by Guido Vollbeding.
shoaib_ahmed 0:791a779d6220 6 * This file is part of the Independent JPEG Group's software.
shoaib_ahmed 0:791a779d6220 7 * For conditions of distribution and use, see the accompanying README file.
shoaib_ahmed 0:791a779d6220 8 *
shoaib_ahmed 0:791a779d6220 9 * This file contains input colorspace conversion routines.
shoaib_ahmed 0:791a779d6220 10 */
shoaib_ahmed 0:791a779d6220 11
shoaib_ahmed 0:791a779d6220 12 #define JPEG_INTERNALS
shoaib_ahmed 0:791a779d6220 13 #include "jinclude.h"
shoaib_ahmed 0:791a779d6220 14 #include "jpeglib.h"
shoaib_ahmed 0:791a779d6220 15
shoaib_ahmed 0:791a779d6220 16
shoaib_ahmed 0:791a779d6220 17 /* Private subobject */
shoaib_ahmed 0:791a779d6220 18
shoaib_ahmed 0:791a779d6220 19 typedef struct {
shoaib_ahmed 0:791a779d6220 20 struct jpeg_color_converter pub; /* public fields */
shoaib_ahmed 0:791a779d6220 21
shoaib_ahmed 0:791a779d6220 22 /* Private state for RGB->YCC conversion */
shoaib_ahmed 0:791a779d6220 23 INT32 * rgb_ycc_tab; /* => table for RGB to YCbCr conversion */
shoaib_ahmed 0:791a779d6220 24 } my_color_converter;
shoaib_ahmed 0:791a779d6220 25
shoaib_ahmed 0:791a779d6220 26 typedef my_color_converter * my_cconvert_ptr;
shoaib_ahmed 0:791a779d6220 27
shoaib_ahmed 0:791a779d6220 28
shoaib_ahmed 0:791a779d6220 29 /**************** RGB -> YCbCr conversion: most common case **************/
shoaib_ahmed 0:791a779d6220 30
shoaib_ahmed 0:791a779d6220 31 /*
shoaib_ahmed 0:791a779d6220 32 * YCbCr is defined per Recommendation ITU-R BT.601-7 (03/2011),
shoaib_ahmed 0:791a779d6220 33 * previously known as Recommendation CCIR 601-1, except that Cb and Cr
shoaib_ahmed 0:791a779d6220 34 * are normalized to the range 0..MAXJSAMPLE rather than -0.5 .. 0.5.
shoaib_ahmed 0:791a779d6220 35 * sRGB (standard RGB color space) is defined per IEC 61966-2-1:1999.
shoaib_ahmed 0:791a779d6220 36 * sYCC (standard luma-chroma-chroma color space with extended gamut)
shoaib_ahmed 0:791a779d6220 37 * is defined per IEC 61966-2-1:1999 Amendment A1:2003 Annex F.
shoaib_ahmed 0:791a779d6220 38 * bg-sRGB and bg-sYCC (big gamut standard color spaces)
shoaib_ahmed 0:791a779d6220 39 * are defined per IEC 61966-2-1:1999 Amendment A1:2003 Annex G.
shoaib_ahmed 0:791a779d6220 40 * Note that the derived conversion coefficients given in some of these
shoaib_ahmed 0:791a779d6220 41 * documents are imprecise. The general conversion equations are
shoaib_ahmed 0:791a779d6220 42 * Y = Kr * R + (1 - Kr - Kb) * G + Kb * B
shoaib_ahmed 0:791a779d6220 43 * Cb = 0.5 * (B - Y) / (1 - Kb)
shoaib_ahmed 0:791a779d6220 44 * Cr = 0.5 * (R - Y) / (1 - Kr)
shoaib_ahmed 0:791a779d6220 45 * With Kr = 0.299 and Kb = 0.114 (derived according to SMPTE RP 177-1993
shoaib_ahmed 0:791a779d6220 46 * from the 1953 FCC NTSC primaries and CIE Illuminant C),
shoaib_ahmed 0:791a779d6220 47 * the conversion equations to be implemented are therefore
shoaib_ahmed 0:791a779d6220 48 * Y = 0.299 * R + 0.587 * G + 0.114 * B
shoaib_ahmed 0:791a779d6220 49 * Cb = -0.168735892 * R - 0.331264108 * G + 0.5 * B + CENTERJSAMPLE
shoaib_ahmed 0:791a779d6220 50 * Cr = 0.5 * R - 0.418687589 * G - 0.081312411 * B + CENTERJSAMPLE
shoaib_ahmed 0:791a779d6220 51 * Note: older versions of the IJG code used a zero offset of MAXJSAMPLE/2,
shoaib_ahmed 0:791a779d6220 52 * rather than CENTERJSAMPLE, for Cb and Cr. This gave equal positive and
shoaib_ahmed 0:791a779d6220 53 * negative swings for Cb/Cr, but meant that grayscale values (Cb=Cr=0)
shoaib_ahmed 0:791a779d6220 54 * were not represented exactly. Now we sacrifice exact representation of
shoaib_ahmed 0:791a779d6220 55 * maximum red and maximum blue in order to get exact grayscales.
shoaib_ahmed 0:791a779d6220 56 *
shoaib_ahmed 0:791a779d6220 57 * To avoid floating-point arithmetic, we represent the fractional constants
shoaib_ahmed 0:791a779d6220 58 * as integers scaled up by 2^16 (about 4 digits precision); we have to divide
shoaib_ahmed 0:791a779d6220 59 * the products by 2^16, with appropriate rounding, to get the correct answer.
shoaib_ahmed 0:791a779d6220 60 *
shoaib_ahmed 0:791a779d6220 61 * For even more speed, we avoid doing any multiplications in the inner loop
shoaib_ahmed 0:791a779d6220 62 * by precalculating the constants times R,G,B for all possible values.
shoaib_ahmed 0:791a779d6220 63 * For 8-bit JSAMPLEs this is very reasonable (only 256 entries per table);
shoaib_ahmed 0:791a779d6220 64 * for 9-bit to 12-bit samples it is still acceptable. It's not very
shoaib_ahmed 0:791a779d6220 65 * reasonable for 16-bit samples, but if you want lossless storage you
shoaib_ahmed 0:791a779d6220 66 * shouldn't be changing colorspace anyway.
shoaib_ahmed 0:791a779d6220 67 * The CENTERJSAMPLE offsets and the rounding fudge-factor of 0.5 are included
shoaib_ahmed 0:791a779d6220 68 * in the tables to save adding them separately in the inner loop.
shoaib_ahmed 0:791a779d6220 69 */
shoaib_ahmed 0:791a779d6220 70
shoaib_ahmed 0:791a779d6220 71 #define SCALEBITS 16 /* speediest right-shift on some machines */
shoaib_ahmed 0:791a779d6220 72 #define CBCR_OFFSET ((INT32) CENTERJSAMPLE << SCALEBITS)
shoaib_ahmed 0:791a779d6220 73 #define ONE_HALF ((INT32) 1 << (SCALEBITS-1))
shoaib_ahmed 0:791a779d6220 74 #define FIX(x) ((INT32) ((x) * (1L<<SCALEBITS) + 0.5))
shoaib_ahmed 0:791a779d6220 75
shoaib_ahmed 0:791a779d6220 76 /* We allocate one big table and divide it up into eight parts, instead of
shoaib_ahmed 0:791a779d6220 77 * doing eight alloc_small requests. This lets us use a single table base
shoaib_ahmed 0:791a779d6220 78 * address, which can be held in a register in the inner loops on many
shoaib_ahmed 0:791a779d6220 79 * machines (more than can hold all eight addresses, anyway).
shoaib_ahmed 0:791a779d6220 80 */
shoaib_ahmed 0:791a779d6220 81
shoaib_ahmed 0:791a779d6220 82 #define R_Y_OFF 0 /* offset to R => Y section */
shoaib_ahmed 0:791a779d6220 83 #define G_Y_OFF (1*(MAXJSAMPLE+1)) /* offset to G => Y section */
shoaib_ahmed 0:791a779d6220 84 #define B_Y_OFF (2*(MAXJSAMPLE+1)) /* etc. */
shoaib_ahmed 0:791a779d6220 85 #define R_CB_OFF (3*(MAXJSAMPLE+1))
shoaib_ahmed 0:791a779d6220 86 #define G_CB_OFF (4*(MAXJSAMPLE+1))
shoaib_ahmed 0:791a779d6220 87 #define B_CB_OFF (5*(MAXJSAMPLE+1))
shoaib_ahmed 0:791a779d6220 88 #define R_CR_OFF B_CB_OFF /* B=>Cb, R=>Cr are the same */
shoaib_ahmed 0:791a779d6220 89 #define G_CR_OFF (6*(MAXJSAMPLE+1))
shoaib_ahmed 0:791a779d6220 90 #define B_CR_OFF (7*(MAXJSAMPLE+1))
shoaib_ahmed 0:791a779d6220 91 #define TABLE_SIZE (8*(MAXJSAMPLE+1))
shoaib_ahmed 0:791a779d6220 92
shoaib_ahmed 0:791a779d6220 93
shoaib_ahmed 0:791a779d6220 94 /*
shoaib_ahmed 0:791a779d6220 95 * Initialize for RGB->YCC colorspace conversion.
shoaib_ahmed 0:791a779d6220 96 */
shoaib_ahmed 0:791a779d6220 97
shoaib_ahmed 0:791a779d6220 98 METHODDEF(void)
shoaib_ahmed 0:791a779d6220 99 rgb_ycc_start (j_compress_ptr cinfo)
shoaib_ahmed 0:791a779d6220 100 {
shoaib_ahmed 0:791a779d6220 101 my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
shoaib_ahmed 0:791a779d6220 102 INT32 * rgb_ycc_tab;
shoaib_ahmed 0:791a779d6220 103 INT32 i;
shoaib_ahmed 0:791a779d6220 104
shoaib_ahmed 0:791a779d6220 105 /* Allocate and fill in the conversion tables. */
shoaib_ahmed 0:791a779d6220 106 cconvert->rgb_ycc_tab = rgb_ycc_tab = (INT32 *)
shoaib_ahmed 0:791a779d6220 107 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
shoaib_ahmed 0:791a779d6220 108 (TABLE_SIZE * SIZEOF(INT32)));
shoaib_ahmed 0:791a779d6220 109
shoaib_ahmed 0:791a779d6220 110 for (i = 0; i <= MAXJSAMPLE; i++) {
shoaib_ahmed 0:791a779d6220 111 rgb_ycc_tab[i+R_Y_OFF] = FIX(0.299) * i;
shoaib_ahmed 0:791a779d6220 112 rgb_ycc_tab[i+G_Y_OFF] = FIX(0.587) * i;
shoaib_ahmed 0:791a779d6220 113 rgb_ycc_tab[i+B_Y_OFF] = FIX(0.114) * i + ONE_HALF;
shoaib_ahmed 0:791a779d6220 114 rgb_ycc_tab[i+R_CB_OFF] = (-FIX(0.168735892)) * i;
shoaib_ahmed 0:791a779d6220 115 rgb_ycc_tab[i+G_CB_OFF] = (-FIX(0.331264108)) * i;
shoaib_ahmed 0:791a779d6220 116 /* We use a rounding fudge-factor of 0.5-epsilon for Cb and Cr.
shoaib_ahmed 0:791a779d6220 117 * This ensures that the maximum output will round to MAXJSAMPLE
shoaib_ahmed 0:791a779d6220 118 * not MAXJSAMPLE+1, and thus that we don't have to range-limit.
shoaib_ahmed 0:791a779d6220 119 */
shoaib_ahmed 0:791a779d6220 120 rgb_ycc_tab[i+B_CB_OFF] = FIX(0.5) * i + CBCR_OFFSET + ONE_HALF-1;
shoaib_ahmed 0:791a779d6220 121 /* B=>Cb and R=>Cr tables are the same
shoaib_ahmed 0:791a779d6220 122 rgb_ycc_tab[i+R_CR_OFF] = FIX(0.5) * i + CBCR_OFFSET + ONE_HALF-1;
shoaib_ahmed 0:791a779d6220 123 */
shoaib_ahmed 0:791a779d6220 124 rgb_ycc_tab[i+G_CR_OFF] = (-FIX(0.418687589)) * i;
shoaib_ahmed 0:791a779d6220 125 rgb_ycc_tab[i+B_CR_OFF] = (-FIX(0.081312411)) * i;
shoaib_ahmed 0:791a779d6220 126 }
shoaib_ahmed 0:791a779d6220 127 }
shoaib_ahmed 0:791a779d6220 128
shoaib_ahmed 0:791a779d6220 129
shoaib_ahmed 0:791a779d6220 130 /*
shoaib_ahmed 0:791a779d6220 131 * Convert some rows of samples to the JPEG colorspace.
shoaib_ahmed 0:791a779d6220 132 *
shoaib_ahmed 0:791a779d6220 133 * Note that we change from the application's interleaved-pixel format
shoaib_ahmed 0:791a779d6220 134 * to our internal noninterleaved, one-plane-per-component format.
shoaib_ahmed 0:791a779d6220 135 * The input buffer is therefore three times as wide as the output buffer.
shoaib_ahmed 0:791a779d6220 136 *
shoaib_ahmed 0:791a779d6220 137 * A starting row offset is provided only for the output buffer. The caller
shoaib_ahmed 0:791a779d6220 138 * can easily adjust the passed input_buf value to accommodate any row
shoaib_ahmed 0:791a779d6220 139 * offset required on that side.
shoaib_ahmed 0:791a779d6220 140 */
shoaib_ahmed 0:791a779d6220 141
shoaib_ahmed 0:791a779d6220 142 METHODDEF(void)
shoaib_ahmed 0:791a779d6220 143 rgb_ycc_convert (j_compress_ptr cinfo,
shoaib_ahmed 0:791a779d6220 144 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
shoaib_ahmed 0:791a779d6220 145 JDIMENSION output_row, int num_rows)
shoaib_ahmed 0:791a779d6220 146 {
shoaib_ahmed 0:791a779d6220 147 my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
shoaib_ahmed 0:791a779d6220 148 register INT32 * ctab = cconvert->rgb_ycc_tab;
shoaib_ahmed 0:791a779d6220 149 register int r, g, b;
shoaib_ahmed 0:791a779d6220 150 register JSAMPROW inptr;
shoaib_ahmed 0:791a779d6220 151 register JSAMPROW outptr0, outptr1, outptr2;
shoaib_ahmed 0:791a779d6220 152 register JDIMENSION col;
shoaib_ahmed 0:791a779d6220 153 JDIMENSION num_cols = cinfo->image_width;
shoaib_ahmed 0:791a779d6220 154
shoaib_ahmed 0:791a779d6220 155 while (--num_rows >= 0) {
shoaib_ahmed 0:791a779d6220 156 inptr = *input_buf++;
shoaib_ahmed 0:791a779d6220 157 outptr0 = output_buf[0][output_row];
shoaib_ahmed 0:791a779d6220 158 outptr1 = output_buf[1][output_row];
shoaib_ahmed 0:791a779d6220 159 outptr2 = output_buf[2][output_row];
shoaib_ahmed 0:791a779d6220 160 output_row++;
shoaib_ahmed 0:791a779d6220 161 for (col = 0; col < num_cols; col++) {
shoaib_ahmed 0:791a779d6220 162 r = GETJSAMPLE(inptr[RGB_RED]);
shoaib_ahmed 0:791a779d6220 163 g = GETJSAMPLE(inptr[RGB_GREEN]);
shoaib_ahmed 0:791a779d6220 164 b = GETJSAMPLE(inptr[RGB_BLUE]);
shoaib_ahmed 0:791a779d6220 165 /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations
shoaib_ahmed 0:791a779d6220 166 * must be too; we do not need an explicit range-limiting operation.
shoaib_ahmed 0:791a779d6220 167 * Hence the value being shifted is never negative, and we don't
shoaib_ahmed 0:791a779d6220 168 * need the general RIGHT_SHIFT macro.
shoaib_ahmed 0:791a779d6220 169 */
shoaib_ahmed 0:791a779d6220 170 /* Y */
shoaib_ahmed 0:791a779d6220 171 outptr0[col] = (JSAMPLE)
shoaib_ahmed 0:791a779d6220 172 ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])
shoaib_ahmed 0:791a779d6220 173 >> SCALEBITS);
shoaib_ahmed 0:791a779d6220 174 /* Cb */
shoaib_ahmed 0:791a779d6220 175 outptr1[col] = (JSAMPLE)
shoaib_ahmed 0:791a779d6220 176 ((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF])
shoaib_ahmed 0:791a779d6220 177 >> SCALEBITS);
shoaib_ahmed 0:791a779d6220 178 /* Cr */
shoaib_ahmed 0:791a779d6220 179 outptr2[col] = (JSAMPLE)
shoaib_ahmed 0:791a779d6220 180 ((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF])
shoaib_ahmed 0:791a779d6220 181 >> SCALEBITS);
shoaib_ahmed 0:791a779d6220 182 inptr += RGB_PIXELSIZE;
shoaib_ahmed 0:791a779d6220 183 }
shoaib_ahmed 0:791a779d6220 184 }
shoaib_ahmed 0:791a779d6220 185 }
shoaib_ahmed 0:791a779d6220 186
shoaib_ahmed 0:791a779d6220 187
shoaib_ahmed 0:791a779d6220 188 /**************** Cases other than RGB -> YCbCr **************/
shoaib_ahmed 0:791a779d6220 189
shoaib_ahmed 0:791a779d6220 190
shoaib_ahmed 0:791a779d6220 191 /*
shoaib_ahmed 0:791a779d6220 192 * Convert some rows of samples to the JPEG colorspace.
shoaib_ahmed 0:791a779d6220 193 * This version handles RGB->grayscale conversion, which is the same
shoaib_ahmed 0:791a779d6220 194 * as the RGB->Y portion of RGB->YCbCr.
shoaib_ahmed 0:791a779d6220 195 * We assume rgb_ycc_start has been called (we only use the Y tables).
shoaib_ahmed 0:791a779d6220 196 */
shoaib_ahmed 0:791a779d6220 197
shoaib_ahmed 0:791a779d6220 198 METHODDEF(void)
shoaib_ahmed 0:791a779d6220 199 rgb_gray_convert (j_compress_ptr cinfo,
shoaib_ahmed 0:791a779d6220 200 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
shoaib_ahmed 0:791a779d6220 201 JDIMENSION output_row, int num_rows)
shoaib_ahmed 0:791a779d6220 202 {
shoaib_ahmed 0:791a779d6220 203 my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
shoaib_ahmed 0:791a779d6220 204 register INT32 * ctab = cconvert->rgb_ycc_tab;
shoaib_ahmed 0:791a779d6220 205 register int r, g, b;
shoaib_ahmed 0:791a779d6220 206 register JSAMPROW inptr;
shoaib_ahmed 0:791a779d6220 207 register JSAMPROW outptr;
shoaib_ahmed 0:791a779d6220 208 register JDIMENSION col;
shoaib_ahmed 0:791a779d6220 209 JDIMENSION num_cols = cinfo->image_width;
shoaib_ahmed 0:791a779d6220 210
shoaib_ahmed 0:791a779d6220 211 while (--num_rows >= 0) {
shoaib_ahmed 0:791a779d6220 212 inptr = *input_buf++;
shoaib_ahmed 0:791a779d6220 213 outptr = output_buf[0][output_row++];
shoaib_ahmed 0:791a779d6220 214 for (col = 0; col < num_cols; col++) {
shoaib_ahmed 0:791a779d6220 215 r = GETJSAMPLE(inptr[RGB_RED]);
shoaib_ahmed 0:791a779d6220 216 g = GETJSAMPLE(inptr[RGB_GREEN]);
shoaib_ahmed 0:791a779d6220 217 b = GETJSAMPLE(inptr[RGB_BLUE]);
shoaib_ahmed 0:791a779d6220 218 /* Y */
shoaib_ahmed 0:791a779d6220 219 outptr[col] = (JSAMPLE)
shoaib_ahmed 0:791a779d6220 220 ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])
shoaib_ahmed 0:791a779d6220 221 >> SCALEBITS);
shoaib_ahmed 0:791a779d6220 222 inptr += RGB_PIXELSIZE;
shoaib_ahmed 0:791a779d6220 223 }
shoaib_ahmed 0:791a779d6220 224 }
shoaib_ahmed 0:791a779d6220 225 }
shoaib_ahmed 0:791a779d6220 226
shoaib_ahmed 0:791a779d6220 227
shoaib_ahmed 0:791a779d6220 228 /*
shoaib_ahmed 0:791a779d6220 229 * Convert some rows of samples to the JPEG colorspace.
shoaib_ahmed 0:791a779d6220 230 * This version handles Adobe-style CMYK->YCCK conversion,
shoaib_ahmed 0:791a779d6220 231 * where we convert R=1-C, G=1-M, and B=1-Y to YCbCr using the same
shoaib_ahmed 0:791a779d6220 232 * conversion as above, while passing K (black) unchanged.
shoaib_ahmed 0:791a779d6220 233 * We assume rgb_ycc_start has been called.
shoaib_ahmed 0:791a779d6220 234 */
shoaib_ahmed 0:791a779d6220 235
shoaib_ahmed 0:791a779d6220 236 METHODDEF(void)
shoaib_ahmed 0:791a779d6220 237 cmyk_ycck_convert (j_compress_ptr cinfo,
shoaib_ahmed 0:791a779d6220 238 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
shoaib_ahmed 0:791a779d6220 239 JDIMENSION output_row, int num_rows)
shoaib_ahmed 0:791a779d6220 240 {
shoaib_ahmed 0:791a779d6220 241 my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
shoaib_ahmed 0:791a779d6220 242 register INT32 * ctab = cconvert->rgb_ycc_tab;
shoaib_ahmed 0:791a779d6220 243 register int r, g, b;
shoaib_ahmed 0:791a779d6220 244 register JSAMPROW inptr;
shoaib_ahmed 0:791a779d6220 245 register JSAMPROW outptr0, outptr1, outptr2, outptr3;
shoaib_ahmed 0:791a779d6220 246 register JDIMENSION col;
shoaib_ahmed 0:791a779d6220 247 JDIMENSION num_cols = cinfo->image_width;
shoaib_ahmed 0:791a779d6220 248
shoaib_ahmed 0:791a779d6220 249 while (--num_rows >= 0) {
shoaib_ahmed 0:791a779d6220 250 inptr = *input_buf++;
shoaib_ahmed 0:791a779d6220 251 outptr0 = output_buf[0][output_row];
shoaib_ahmed 0:791a779d6220 252 outptr1 = output_buf[1][output_row];
shoaib_ahmed 0:791a779d6220 253 outptr2 = output_buf[2][output_row];
shoaib_ahmed 0:791a779d6220 254 outptr3 = output_buf[3][output_row];
shoaib_ahmed 0:791a779d6220 255 output_row++;
shoaib_ahmed 0:791a779d6220 256 for (col = 0; col < num_cols; col++) {
shoaib_ahmed 0:791a779d6220 257 r = MAXJSAMPLE - GETJSAMPLE(inptr[0]);
shoaib_ahmed 0:791a779d6220 258 g = MAXJSAMPLE - GETJSAMPLE(inptr[1]);
shoaib_ahmed 0:791a779d6220 259 b = MAXJSAMPLE - GETJSAMPLE(inptr[2]);
shoaib_ahmed 0:791a779d6220 260 /* K passes through as-is */
shoaib_ahmed 0:791a779d6220 261 outptr3[col] = inptr[3]; /* don't need GETJSAMPLE here */
shoaib_ahmed 0:791a779d6220 262 /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations
shoaib_ahmed 0:791a779d6220 263 * must be too; we do not need an explicit range-limiting operation.
shoaib_ahmed 0:791a779d6220 264 * Hence the value being shifted is never negative, and we don't
shoaib_ahmed 0:791a779d6220 265 * need the general RIGHT_SHIFT macro.
shoaib_ahmed 0:791a779d6220 266 */
shoaib_ahmed 0:791a779d6220 267 /* Y */
shoaib_ahmed 0:791a779d6220 268 outptr0[col] = (JSAMPLE)
shoaib_ahmed 0:791a779d6220 269 ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])
shoaib_ahmed 0:791a779d6220 270 >> SCALEBITS);
shoaib_ahmed 0:791a779d6220 271 /* Cb */
shoaib_ahmed 0:791a779d6220 272 outptr1[col] = (JSAMPLE)
shoaib_ahmed 0:791a779d6220 273 ((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF])
shoaib_ahmed 0:791a779d6220 274 >> SCALEBITS);
shoaib_ahmed 0:791a779d6220 275 /* Cr */
shoaib_ahmed 0:791a779d6220 276 outptr2[col] = (JSAMPLE)
shoaib_ahmed 0:791a779d6220 277 ((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF])
shoaib_ahmed 0:791a779d6220 278 >> SCALEBITS);
shoaib_ahmed 0:791a779d6220 279 inptr += 4;
shoaib_ahmed 0:791a779d6220 280 }
shoaib_ahmed 0:791a779d6220 281 }
shoaib_ahmed 0:791a779d6220 282 }
shoaib_ahmed 0:791a779d6220 283
shoaib_ahmed 0:791a779d6220 284
shoaib_ahmed 0:791a779d6220 285 /*
shoaib_ahmed 0:791a779d6220 286 * Convert some rows of samples to the JPEG colorspace.
shoaib_ahmed 0:791a779d6220 287 * [R,G,B] to [R-G,G,B-G] conversion with modulo calculation
shoaib_ahmed 0:791a779d6220 288 * (forward reversible color transform).
shoaib_ahmed 0:791a779d6220 289 * This can be seen as an adaption of the general RGB->YCbCr
shoaib_ahmed 0:791a779d6220 290 * conversion equation with Kr = Kb = 0, while replacing the
shoaib_ahmed 0:791a779d6220 291 * normalization by modulo calculation.
shoaib_ahmed 0:791a779d6220 292 */
shoaib_ahmed 0:791a779d6220 293
shoaib_ahmed 0:791a779d6220 294 METHODDEF(void)
shoaib_ahmed 0:791a779d6220 295 rgb_rgb1_convert (j_compress_ptr cinfo,
shoaib_ahmed 0:791a779d6220 296 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
shoaib_ahmed 0:791a779d6220 297 JDIMENSION output_row, int num_rows)
shoaib_ahmed 0:791a779d6220 298 {
shoaib_ahmed 0:791a779d6220 299 register int r, g, b;
shoaib_ahmed 0:791a779d6220 300 register JSAMPROW inptr;
shoaib_ahmed 0:791a779d6220 301 register JSAMPROW outptr0, outptr1, outptr2;
shoaib_ahmed 0:791a779d6220 302 register JDIMENSION col;
shoaib_ahmed 0:791a779d6220 303 JDIMENSION num_cols = cinfo->image_width;
shoaib_ahmed 0:791a779d6220 304
shoaib_ahmed 0:791a779d6220 305 while (--num_rows >= 0) {
shoaib_ahmed 0:791a779d6220 306 inptr = *input_buf++;
shoaib_ahmed 0:791a779d6220 307 outptr0 = output_buf[0][output_row];
shoaib_ahmed 0:791a779d6220 308 outptr1 = output_buf[1][output_row];
shoaib_ahmed 0:791a779d6220 309 outptr2 = output_buf[2][output_row];
shoaib_ahmed 0:791a779d6220 310 output_row++;
shoaib_ahmed 0:791a779d6220 311 for (col = 0; col < num_cols; col++) {
shoaib_ahmed 0:791a779d6220 312 r = GETJSAMPLE(inptr[RGB_RED]);
shoaib_ahmed 0:791a779d6220 313 g = GETJSAMPLE(inptr[RGB_GREEN]);
shoaib_ahmed 0:791a779d6220 314 b = GETJSAMPLE(inptr[RGB_BLUE]);
shoaib_ahmed 0:791a779d6220 315 /* Assume that MAXJSAMPLE+1 is a power of 2, so that the MOD
shoaib_ahmed 0:791a779d6220 316 * (modulo) operator is equivalent to the bitmask operator AND.
shoaib_ahmed 0:791a779d6220 317 */
shoaib_ahmed 0:791a779d6220 318 outptr0[col] = (JSAMPLE) ((r - g + CENTERJSAMPLE) & MAXJSAMPLE);
shoaib_ahmed 0:791a779d6220 319 outptr1[col] = (JSAMPLE) g;
shoaib_ahmed 0:791a779d6220 320 outptr2[col] = (JSAMPLE) ((b - g + CENTERJSAMPLE) & MAXJSAMPLE);
shoaib_ahmed 0:791a779d6220 321 inptr += RGB_PIXELSIZE;
shoaib_ahmed 0:791a779d6220 322 }
shoaib_ahmed 0:791a779d6220 323 }
shoaib_ahmed 0:791a779d6220 324 }
shoaib_ahmed 0:791a779d6220 325
shoaib_ahmed 0:791a779d6220 326
shoaib_ahmed 0:791a779d6220 327 /*
shoaib_ahmed 0:791a779d6220 328 * Convert some rows of samples to the JPEG colorspace.
shoaib_ahmed 0:791a779d6220 329 * This version handles grayscale output with no conversion.
shoaib_ahmed 0:791a779d6220 330 * The source can be either plain grayscale or YCC (since Y == gray).
shoaib_ahmed 0:791a779d6220 331 */
shoaib_ahmed 0:791a779d6220 332
shoaib_ahmed 0:791a779d6220 333 METHODDEF(void)
shoaib_ahmed 0:791a779d6220 334 grayscale_convert (j_compress_ptr cinfo,
shoaib_ahmed 0:791a779d6220 335 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
shoaib_ahmed 0:791a779d6220 336 JDIMENSION output_row, int num_rows)
shoaib_ahmed 0:791a779d6220 337 {
shoaib_ahmed 0:791a779d6220 338 int instride = cinfo->input_components;
shoaib_ahmed 0:791a779d6220 339 register JSAMPROW inptr;
shoaib_ahmed 0:791a779d6220 340 register JSAMPROW outptr;
shoaib_ahmed 0:791a779d6220 341 register JDIMENSION col;
shoaib_ahmed 0:791a779d6220 342 JDIMENSION num_cols = cinfo->image_width;
shoaib_ahmed 0:791a779d6220 343
shoaib_ahmed 0:791a779d6220 344 while (--num_rows >= 0) {
shoaib_ahmed 0:791a779d6220 345 inptr = *input_buf++;
shoaib_ahmed 0:791a779d6220 346 outptr = output_buf[0][output_row++];
shoaib_ahmed 0:791a779d6220 347 for (col = 0; col < num_cols; col++) {
shoaib_ahmed 0:791a779d6220 348 outptr[col] = inptr[0]; /* don't need GETJSAMPLE() here */
shoaib_ahmed 0:791a779d6220 349 inptr += instride;
shoaib_ahmed 0:791a779d6220 350 }
shoaib_ahmed 0:791a779d6220 351 }
shoaib_ahmed 0:791a779d6220 352 }
shoaib_ahmed 0:791a779d6220 353
shoaib_ahmed 0:791a779d6220 354
shoaib_ahmed 0:791a779d6220 355 /*
shoaib_ahmed 0:791a779d6220 356 * Convert some rows of samples to the JPEG colorspace.
shoaib_ahmed 0:791a779d6220 357 * No colorspace conversion, but change from interleaved
shoaib_ahmed 0:791a779d6220 358 * to separate-planes representation.
shoaib_ahmed 0:791a779d6220 359 */
shoaib_ahmed 0:791a779d6220 360
shoaib_ahmed 0:791a779d6220 361 METHODDEF(void)
shoaib_ahmed 0:791a779d6220 362 rgb_convert (j_compress_ptr cinfo,
shoaib_ahmed 0:791a779d6220 363 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
shoaib_ahmed 0:791a779d6220 364 JDIMENSION output_row, int num_rows)
shoaib_ahmed 0:791a779d6220 365 {
shoaib_ahmed 0:791a779d6220 366 register JSAMPROW inptr;
shoaib_ahmed 0:791a779d6220 367 register JSAMPROW outptr0, outptr1, outptr2;
shoaib_ahmed 0:791a779d6220 368 register JDIMENSION col;
shoaib_ahmed 0:791a779d6220 369 JDIMENSION num_cols = cinfo->image_width;
shoaib_ahmed 0:791a779d6220 370
shoaib_ahmed 0:791a779d6220 371 while (--num_rows >= 0) {
shoaib_ahmed 0:791a779d6220 372 inptr = *input_buf++;
shoaib_ahmed 0:791a779d6220 373 outptr0 = output_buf[0][output_row];
shoaib_ahmed 0:791a779d6220 374 outptr1 = output_buf[1][output_row];
shoaib_ahmed 0:791a779d6220 375 outptr2 = output_buf[2][output_row];
shoaib_ahmed 0:791a779d6220 376 output_row++;
shoaib_ahmed 0:791a779d6220 377 for (col = 0; col < num_cols; col++) {
shoaib_ahmed 0:791a779d6220 378 /* We can dispense with GETJSAMPLE() here */
shoaib_ahmed 0:791a779d6220 379 outptr0[col] = inptr[RGB_RED];
shoaib_ahmed 0:791a779d6220 380 outptr1[col] = inptr[RGB_GREEN];
shoaib_ahmed 0:791a779d6220 381 outptr2[col] = inptr[RGB_BLUE];
shoaib_ahmed 0:791a779d6220 382 inptr += RGB_PIXELSIZE;
shoaib_ahmed 0:791a779d6220 383 }
shoaib_ahmed 0:791a779d6220 384 }
shoaib_ahmed 0:791a779d6220 385 }
shoaib_ahmed 0:791a779d6220 386
shoaib_ahmed 0:791a779d6220 387
shoaib_ahmed 0:791a779d6220 388 /*
shoaib_ahmed 0:791a779d6220 389 * Convert some rows of samples to the JPEG colorspace.
shoaib_ahmed 0:791a779d6220 390 * This version handles multi-component colorspaces without conversion.
shoaib_ahmed 0:791a779d6220 391 * We assume input_components == num_components.
shoaib_ahmed 0:791a779d6220 392 */
shoaib_ahmed 0:791a779d6220 393
shoaib_ahmed 0:791a779d6220 394 METHODDEF(void)
shoaib_ahmed 0:791a779d6220 395 null_convert (j_compress_ptr cinfo,
shoaib_ahmed 0:791a779d6220 396 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
shoaib_ahmed 0:791a779d6220 397 JDIMENSION output_row, int num_rows)
shoaib_ahmed 0:791a779d6220 398 {
shoaib_ahmed 0:791a779d6220 399 int ci;
shoaib_ahmed 0:791a779d6220 400 register int nc = cinfo->num_components;
shoaib_ahmed 0:791a779d6220 401 register JSAMPROW inptr;
shoaib_ahmed 0:791a779d6220 402 register JSAMPROW outptr;
shoaib_ahmed 0:791a779d6220 403 register JDIMENSION col;
shoaib_ahmed 0:791a779d6220 404 JDIMENSION num_cols = cinfo->image_width;
shoaib_ahmed 0:791a779d6220 405
shoaib_ahmed 0:791a779d6220 406 while (--num_rows >= 0) {
shoaib_ahmed 0:791a779d6220 407 /* It seems fastest to make a separate pass for each component. */
shoaib_ahmed 0:791a779d6220 408 for (ci = 0; ci < nc; ci++) {
shoaib_ahmed 0:791a779d6220 409 inptr = input_buf[0] + ci;
shoaib_ahmed 0:791a779d6220 410 outptr = output_buf[ci][output_row];
shoaib_ahmed 0:791a779d6220 411 for (col = 0; col < num_cols; col++) {
shoaib_ahmed 0:791a779d6220 412 *outptr++ = *inptr; /* don't need GETJSAMPLE() here */
shoaib_ahmed 0:791a779d6220 413 inptr += nc;
shoaib_ahmed 0:791a779d6220 414 }
shoaib_ahmed 0:791a779d6220 415 }
shoaib_ahmed 0:791a779d6220 416 input_buf++;
shoaib_ahmed 0:791a779d6220 417 output_row++;
shoaib_ahmed 0:791a779d6220 418 }
shoaib_ahmed 0:791a779d6220 419 }
shoaib_ahmed 0:791a779d6220 420
shoaib_ahmed 0:791a779d6220 421
shoaib_ahmed 0:791a779d6220 422 /*
shoaib_ahmed 0:791a779d6220 423 * Empty method for start_pass.
shoaib_ahmed 0:791a779d6220 424 */
shoaib_ahmed 0:791a779d6220 425
shoaib_ahmed 0:791a779d6220 426 METHODDEF(void)
shoaib_ahmed 0:791a779d6220 427 null_method (j_compress_ptr cinfo)
shoaib_ahmed 0:791a779d6220 428 {
shoaib_ahmed 0:791a779d6220 429 /* no work needed */
shoaib_ahmed 0:791a779d6220 430 }
shoaib_ahmed 0:791a779d6220 431
shoaib_ahmed 0:791a779d6220 432
shoaib_ahmed 0:791a779d6220 433 /*
shoaib_ahmed 0:791a779d6220 434 * Module initialization routine for input colorspace conversion.
shoaib_ahmed 0:791a779d6220 435 */
shoaib_ahmed 0:791a779d6220 436
shoaib_ahmed 0:791a779d6220 437 GLOBAL(void)
shoaib_ahmed 0:791a779d6220 438 jinit_color_converter (j_compress_ptr cinfo)
shoaib_ahmed 0:791a779d6220 439 {
shoaib_ahmed 0:791a779d6220 440 my_cconvert_ptr cconvert;
shoaib_ahmed 0:791a779d6220 441
shoaib_ahmed 0:791a779d6220 442 cconvert = (my_cconvert_ptr)
shoaib_ahmed 0:791a779d6220 443 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
shoaib_ahmed 0:791a779d6220 444 SIZEOF(my_color_converter));
shoaib_ahmed 0:791a779d6220 445 cinfo->cconvert = &cconvert->pub;
shoaib_ahmed 0:791a779d6220 446 /* set start_pass to null method until we find out differently */
shoaib_ahmed 0:791a779d6220 447 cconvert->pub.start_pass = null_method;
shoaib_ahmed 0:791a779d6220 448
shoaib_ahmed 0:791a779d6220 449 /* Make sure input_components agrees with in_color_space */
shoaib_ahmed 0:791a779d6220 450 switch (cinfo->in_color_space) {
shoaib_ahmed 0:791a779d6220 451 case JCS_GRAYSCALE:
shoaib_ahmed 0:791a779d6220 452 if (cinfo->input_components != 1)
shoaib_ahmed 0:791a779d6220 453 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
shoaib_ahmed 0:791a779d6220 454 break;
shoaib_ahmed 0:791a779d6220 455
shoaib_ahmed 0:791a779d6220 456 case JCS_RGB:
shoaib_ahmed 0:791a779d6220 457 case JCS_BG_RGB:
shoaib_ahmed 0:791a779d6220 458 if (cinfo->input_components != RGB_PIXELSIZE)
shoaib_ahmed 0:791a779d6220 459 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
shoaib_ahmed 0:791a779d6220 460 break;
shoaib_ahmed 0:791a779d6220 461
shoaib_ahmed 0:791a779d6220 462 case JCS_YCbCr:
shoaib_ahmed 0:791a779d6220 463 case JCS_BG_YCC:
shoaib_ahmed 0:791a779d6220 464 if (cinfo->input_components != 3)
shoaib_ahmed 0:791a779d6220 465 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
shoaib_ahmed 0:791a779d6220 466 break;
shoaib_ahmed 0:791a779d6220 467
shoaib_ahmed 0:791a779d6220 468 case JCS_CMYK:
shoaib_ahmed 0:791a779d6220 469 case JCS_YCCK:
shoaib_ahmed 0:791a779d6220 470 if (cinfo->input_components != 4)
shoaib_ahmed 0:791a779d6220 471 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
shoaib_ahmed 0:791a779d6220 472 break;
shoaib_ahmed 0:791a779d6220 473
shoaib_ahmed 0:791a779d6220 474 default: /* JCS_UNKNOWN can be anything */
shoaib_ahmed 0:791a779d6220 475 if (cinfo->input_components < 1)
shoaib_ahmed 0:791a779d6220 476 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
shoaib_ahmed 0:791a779d6220 477 break;
shoaib_ahmed 0:791a779d6220 478 }
shoaib_ahmed 0:791a779d6220 479
shoaib_ahmed 0:791a779d6220 480 /* Support color transform only for RGB colorspaces */
shoaib_ahmed 0:791a779d6220 481 if (cinfo->color_transform &&
shoaib_ahmed 0:791a779d6220 482 cinfo->jpeg_color_space != JCS_RGB &&
shoaib_ahmed 0:791a779d6220 483 cinfo->jpeg_color_space != JCS_BG_RGB)
shoaib_ahmed 0:791a779d6220 484 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
shoaib_ahmed 0:791a779d6220 485
shoaib_ahmed 0:791a779d6220 486 /* Check num_components, set conversion method based on requested space */
shoaib_ahmed 0:791a779d6220 487 switch (cinfo->jpeg_color_space) {
shoaib_ahmed 0:791a779d6220 488 case JCS_GRAYSCALE:
shoaib_ahmed 0:791a779d6220 489 if (cinfo->num_components != 1)
shoaib_ahmed 0:791a779d6220 490 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
shoaib_ahmed 0:791a779d6220 491 switch (cinfo->in_color_space) {
shoaib_ahmed 0:791a779d6220 492 case JCS_GRAYSCALE:
shoaib_ahmed 0:791a779d6220 493 case JCS_YCbCr:
shoaib_ahmed 0:791a779d6220 494 case JCS_BG_YCC:
shoaib_ahmed 0:791a779d6220 495 cconvert->pub.color_convert = grayscale_convert;
shoaib_ahmed 0:791a779d6220 496 break;
shoaib_ahmed 0:791a779d6220 497 case JCS_RGB:
shoaib_ahmed 0:791a779d6220 498 cconvert->pub.start_pass = rgb_ycc_start;
shoaib_ahmed 0:791a779d6220 499 cconvert->pub.color_convert = rgb_gray_convert;
shoaib_ahmed 0:791a779d6220 500 break;
shoaib_ahmed 0:791a779d6220 501 default:
shoaib_ahmed 0:791a779d6220 502 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
shoaib_ahmed 0:791a779d6220 503 }
shoaib_ahmed 0:791a779d6220 504 break;
shoaib_ahmed 0:791a779d6220 505
shoaib_ahmed 0:791a779d6220 506 case JCS_RGB:
shoaib_ahmed 0:791a779d6220 507 case JCS_BG_RGB:
shoaib_ahmed 0:791a779d6220 508 if (cinfo->num_components != 3)
shoaib_ahmed 0:791a779d6220 509 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
shoaib_ahmed 0:791a779d6220 510 if (cinfo->in_color_space == cinfo->jpeg_color_space) {
shoaib_ahmed 0:791a779d6220 511 switch (cinfo->color_transform) {
shoaib_ahmed 0:791a779d6220 512 case JCT_NONE:
shoaib_ahmed 0:791a779d6220 513 cconvert->pub.color_convert = rgb_convert;
shoaib_ahmed 0:791a779d6220 514 break;
shoaib_ahmed 0:791a779d6220 515 case JCT_SUBTRACT_GREEN:
shoaib_ahmed 0:791a779d6220 516 cconvert->pub.color_convert = rgb_rgb1_convert;
shoaib_ahmed 0:791a779d6220 517 break;
shoaib_ahmed 0:791a779d6220 518 default:
shoaib_ahmed 0:791a779d6220 519 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
shoaib_ahmed 0:791a779d6220 520 }
shoaib_ahmed 0:791a779d6220 521 } else
shoaib_ahmed 0:791a779d6220 522 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
shoaib_ahmed 0:791a779d6220 523 break;
shoaib_ahmed 0:791a779d6220 524
shoaib_ahmed 0:791a779d6220 525 case JCS_YCbCr:
shoaib_ahmed 0:791a779d6220 526 if (cinfo->num_components != 3)
shoaib_ahmed 0:791a779d6220 527 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
shoaib_ahmed 0:791a779d6220 528 switch (cinfo->in_color_space) {
shoaib_ahmed 0:791a779d6220 529 case JCS_RGB:
shoaib_ahmed 0:791a779d6220 530 cconvert->pub.start_pass = rgb_ycc_start;
shoaib_ahmed 0:791a779d6220 531 cconvert->pub.color_convert = rgb_ycc_convert;
shoaib_ahmed 0:791a779d6220 532 break;
shoaib_ahmed 0:791a779d6220 533 case JCS_YCbCr:
shoaib_ahmed 0:791a779d6220 534 cconvert->pub.color_convert = null_convert;
shoaib_ahmed 0:791a779d6220 535 break;
shoaib_ahmed 0:791a779d6220 536 default:
shoaib_ahmed 0:791a779d6220 537 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
shoaib_ahmed 0:791a779d6220 538 }
shoaib_ahmed 0:791a779d6220 539 break;
shoaib_ahmed 0:791a779d6220 540
shoaib_ahmed 0:791a779d6220 541 case JCS_BG_YCC:
shoaib_ahmed 0:791a779d6220 542 if (cinfo->num_components != 3)
shoaib_ahmed 0:791a779d6220 543 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
shoaib_ahmed 0:791a779d6220 544 switch (cinfo->in_color_space) {
shoaib_ahmed 0:791a779d6220 545 case JCS_RGB:
shoaib_ahmed 0:791a779d6220 546 /* For conversion from normal RGB input to BG_YCC representation,
shoaib_ahmed 0:791a779d6220 547 * the Cb/Cr values are first computed as usual, and then
shoaib_ahmed 0:791a779d6220 548 * quantized further after DCT processing by a factor of
shoaib_ahmed 0:791a779d6220 549 * 2 in reference to the nominal quantization factor.
shoaib_ahmed 0:791a779d6220 550 */
shoaib_ahmed 0:791a779d6220 551 /* need quantization scale by factor of 2 after DCT */
shoaib_ahmed 0:791a779d6220 552 cinfo->comp_info[1].component_needed = TRUE;
shoaib_ahmed 0:791a779d6220 553 cinfo->comp_info[2].component_needed = TRUE;
shoaib_ahmed 0:791a779d6220 554 /* compute normal YCC first */
shoaib_ahmed 0:791a779d6220 555 cconvert->pub.start_pass = rgb_ycc_start;
shoaib_ahmed 0:791a779d6220 556 cconvert->pub.color_convert = rgb_ycc_convert;
shoaib_ahmed 0:791a779d6220 557 break;
shoaib_ahmed 0:791a779d6220 558 case JCS_YCbCr:
shoaib_ahmed 0:791a779d6220 559 /* need quantization scale by factor of 2 after DCT */
shoaib_ahmed 0:791a779d6220 560 cinfo->comp_info[1].component_needed = TRUE;
shoaib_ahmed 0:791a779d6220 561 cinfo->comp_info[2].component_needed = TRUE;
shoaib_ahmed 0:791a779d6220 562 /*FALLTHROUGH*/
shoaib_ahmed 0:791a779d6220 563 case JCS_BG_YCC:
shoaib_ahmed 0:791a779d6220 564 /* Pass through for BG_YCC input */
shoaib_ahmed 0:791a779d6220 565 cconvert->pub.color_convert = null_convert;
shoaib_ahmed 0:791a779d6220 566 break;
shoaib_ahmed 0:791a779d6220 567 default:
shoaib_ahmed 0:791a779d6220 568 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
shoaib_ahmed 0:791a779d6220 569 }
shoaib_ahmed 0:791a779d6220 570 break;
shoaib_ahmed 0:791a779d6220 571
shoaib_ahmed 0:791a779d6220 572 case JCS_CMYK:
shoaib_ahmed 0:791a779d6220 573 if (cinfo->num_components != 4)
shoaib_ahmed 0:791a779d6220 574 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
shoaib_ahmed 0:791a779d6220 575 if (cinfo->in_color_space == JCS_CMYK)
shoaib_ahmed 0:791a779d6220 576 cconvert->pub.color_convert = null_convert;
shoaib_ahmed 0:791a779d6220 577 else
shoaib_ahmed 0:791a779d6220 578 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
shoaib_ahmed 0:791a779d6220 579 break;
shoaib_ahmed 0:791a779d6220 580
shoaib_ahmed 0:791a779d6220 581 case JCS_YCCK:
shoaib_ahmed 0:791a779d6220 582 if (cinfo->num_components != 4)
shoaib_ahmed 0:791a779d6220 583 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
shoaib_ahmed 0:791a779d6220 584 switch (cinfo->in_color_space) {
shoaib_ahmed 0:791a779d6220 585 case JCS_CMYK:
shoaib_ahmed 0:791a779d6220 586 cconvert->pub.start_pass = rgb_ycc_start;
shoaib_ahmed 0:791a779d6220 587 cconvert->pub.color_convert = cmyk_ycck_convert;
shoaib_ahmed 0:791a779d6220 588 break;
shoaib_ahmed 0:791a779d6220 589 case JCS_YCCK:
shoaib_ahmed 0:791a779d6220 590 cconvert->pub.color_convert = null_convert;
shoaib_ahmed 0:791a779d6220 591 break;
shoaib_ahmed 0:791a779d6220 592 default:
shoaib_ahmed 0:791a779d6220 593 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
shoaib_ahmed 0:791a779d6220 594 }
shoaib_ahmed 0:791a779d6220 595 break;
shoaib_ahmed 0:791a779d6220 596
shoaib_ahmed 0:791a779d6220 597 default: /* allow null conversion of JCS_UNKNOWN */
shoaib_ahmed 0:791a779d6220 598 if (cinfo->jpeg_color_space != cinfo->in_color_space ||
shoaib_ahmed 0:791a779d6220 599 cinfo->num_components != cinfo->input_components)
shoaib_ahmed 0:791a779d6220 600 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
shoaib_ahmed 0:791a779d6220 601 cconvert->pub.color_convert = null_convert;
shoaib_ahmed 0:791a779d6220 602 break;
shoaib_ahmed 0:791a779d6220 603 }
shoaib_ahmed 0:791a779d6220 604 }