diff options
author | Tim Angus <tim@ngus.net> | 2009-10-03 11:58:50 +0000 |
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committer | Tim Angus <tim@ngus.net> | 2013-01-03 00:15:34 +0000 |
commit | ac3e5586cd56657ff1b6f5f64af7e1d7c76b410d (patch) | |
tree | b245f2cbd4e7491b948aea5c7c080be61307c950 /src/jpeg-6/jdcolor.c | |
parent | dc3819f1e99d8159bdb0ea1da26506b00fe78e62 (diff) |
* Merge ioq3-r1458
Diffstat (limited to 'src/jpeg-6/jdcolor.c')
-rw-r--r-- | src/jpeg-6/jdcolor.c | 367 |
1 files changed, 0 insertions, 367 deletions
diff --git a/src/jpeg-6/jdcolor.c b/src/jpeg-6/jdcolor.c deleted file mode 100644 index b2bdf6ee..00000000 --- a/src/jpeg-6/jdcolor.c +++ /dev/null @@ -1,367 +0,0 @@ -/* - * jdcolor.c - * - * Copyright (C) 1991-1995, Thomas G. Lane. - * This file is part of the Independent JPEG Group's software. - * For conditions of distribution and use, see the accompanying README file. - * - * This file contains output colorspace conversion routines. - */ - -#define JPEG_INTERNALS -#include "jinclude.h" -#include "jpeglib.h" - - -/* Private subobject */ - -typedef struct { - struct jpeg_color_deconverter pub; /* public fields */ - - /* Private state for YCC->RGB conversion */ - int * Cr_r_tab; /* => table for Cr to R conversion */ - int * Cb_b_tab; /* => table for Cb to B conversion */ - INT32 * Cr_g_tab; /* => table for Cr to G conversion */ - INT32 * Cb_g_tab; /* => table for Cb to G conversion */ -} my_color_deconverter; - -typedef my_color_deconverter * my_cconvert_ptr; - - -/**************** YCbCr -> RGB conversion: most common case **************/ - -/* - * YCbCr is defined per CCIR 601-1, except that Cb and Cr are - * normalized to the range 0..MAXJSAMPLE rather than -0.5 .. 0.5. - * The conversion equations to be implemented are therefore - * R = Y + 1.40200 * Cr - * G = Y - 0.34414 * Cb - 0.71414 * Cr - * B = Y + 1.77200 * Cb - * where Cb and Cr represent the incoming values less CENTERJSAMPLE. - * (These numbers are derived from TIFF 6.0 section 21, dated 3-June-92.) - * - * To avoid floating-point arithmetic, we represent the fractional constants - * as integers scaled up by 2^16 (about 4 digits precision); we have to divide - * the products by 2^16, with appropriate rounding, to get the correct answer. - * Notice that Y, being an integral input, does not contribute any fraction - * so it need not participate in the rounding. - * - * For even more speed, we avoid doing any multiplications in the inner loop - * by precalculating the constants times Cb and Cr for all possible values. - * For 8-bit JSAMPLEs this is very reasonable (only 256 entries per table); - * for 12-bit samples it is still acceptable. It's not very reasonable for - * 16-bit samples, but if you want lossless storage you shouldn't be changing - * colorspace anyway. - * The Cr=>R and Cb=>B values can be rounded to integers in advance; the - * values for the G calculation are left scaled up, since we must add them - * together before rounding. - */ - -#define SCALEBITS 16 /* speediest right-shift on some machines */ -#define ONE_HALF ((INT32) 1 << (SCALEBITS-1)) -#define FIX(x) ((INT32) ((x) * (1L<<SCALEBITS) + 0.5)) - - -/* - * Initialize tables for YCC->RGB colorspace conversion. - */ - -LOCAL void -build_ycc_rgb_table (j_decompress_ptr cinfo) -{ - my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; - int i; - INT32 x; - SHIFT_TEMPS - - cconvert->Cr_r_tab = (int *) - (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, - (MAXJSAMPLE+1) * SIZEOF(int)); - cconvert->Cb_b_tab = (int *) - (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, - (MAXJSAMPLE+1) * SIZEOF(int)); - cconvert->Cr_g_tab = (INT32 *) - (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, - (MAXJSAMPLE+1) * SIZEOF(INT32)); - cconvert->Cb_g_tab = (INT32 *) - (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, - (MAXJSAMPLE+1) * SIZEOF(INT32)); - - for (i = 0, x = -CENTERJSAMPLE; i <= MAXJSAMPLE; i++, x++) { - /* i is the actual input pixel value, in the range 0..MAXJSAMPLE */ - /* The Cb or Cr value we are thinking of is x = i - CENTERJSAMPLE */ - /* Cr=>R value is nearest int to 1.40200 * x */ - cconvert->Cr_r_tab[i] = (int) - RIGHT_SHIFT(FIX(1.40200) * x + ONE_HALF, SCALEBITS); - /* Cb=>B value is nearest int to 1.77200 * x */ - cconvert->Cb_b_tab[i] = (int) - RIGHT_SHIFT(FIX(1.77200) * x + ONE_HALF, SCALEBITS); - /* Cr=>G value is scaled-up -0.71414 * x */ - cconvert->Cr_g_tab[i] = (- FIX(0.71414)) * x; - /* Cb=>G value is scaled-up -0.34414 * x */ - /* We also add in ONE_HALF so that need not do it in inner loop */ - cconvert->Cb_g_tab[i] = (- FIX(0.34414)) * x + ONE_HALF; - } -} - - -/* - * Convert some rows of samples to the output colorspace. - * - * Note that we change from noninterleaved, one-plane-per-component format - * to interleaved-pixel format. The output buffer is therefore three times - * as wide as the input buffer. - * A starting row offset is provided only for the input buffer. The caller - * can easily adjust the passed output_buf value to accommodate any row - * offset required on that side. - */ - -METHODDEF void -ycc_rgb_convert (j_decompress_ptr cinfo, - JSAMPIMAGE input_buf, JDIMENSION input_row, - JSAMPARRAY output_buf, int num_rows) -{ - my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; - register int y, cb, cr; - register JSAMPROW outptr; - register JSAMPROW inptr0, inptr1, inptr2; - register JDIMENSION col; - JDIMENSION num_cols = cinfo->output_width; - /* copy these pointers into registers if possible */ - register JSAMPLE * range_limit = cinfo->sample_range_limit; - register int * Crrtab = cconvert->Cr_r_tab; - register int * Cbbtab = cconvert->Cb_b_tab; - register INT32 * Crgtab = cconvert->Cr_g_tab; - register INT32 * Cbgtab = cconvert->Cb_g_tab; - SHIFT_TEMPS - - while (--num_rows >= 0) { - inptr0 = input_buf[0][input_row]; - inptr1 = input_buf[1][input_row]; - inptr2 = input_buf[2][input_row]; - input_row++; - outptr = *output_buf++; - for (col = 0; col < num_cols; col++) { - y = GETJSAMPLE(inptr0[col]); - cb = GETJSAMPLE(inptr1[col]); - cr = GETJSAMPLE(inptr2[col]); - /* Range-limiting is essential due to noise introduced by DCT losses. */ - outptr[RGB_RED] = range_limit[y + Crrtab[cr]]; - outptr[RGB_GREEN] = range_limit[y + - ((int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], - SCALEBITS))]; - outptr[RGB_BLUE] = range_limit[y + Cbbtab[cb]]; - outptr += RGB_PIXELSIZE; - } - } -} - - -/**************** Cases other than YCbCr -> RGB **************/ - - -/* - * Color conversion for no colorspace change: just copy the data, - * converting from separate-planes to interleaved representation. - */ - -METHODDEF void -null_convert (j_decompress_ptr cinfo, - JSAMPIMAGE input_buf, JDIMENSION input_row, - JSAMPARRAY output_buf, int num_rows) -{ - register JSAMPROW inptr, outptr; - register JDIMENSION count; - register int num_components = cinfo->num_components; - JDIMENSION num_cols = cinfo->output_width; - int ci; - - while (--num_rows >= 0) { - for (ci = 0; ci < num_components; ci++) { - inptr = input_buf[ci][input_row]; - outptr = output_buf[0] + ci; - for (count = num_cols; count > 0; count--) { - *outptr = *inptr++; /* needn't bother with GETJSAMPLE() here */ - outptr += num_components; - } - } - input_row++; - output_buf++; - } -} - - -/* - * Color conversion for grayscale: just copy the data. - * This also works for YCbCr -> grayscale conversion, in which - * we just copy the Y (luminance) component and ignore chrominance. - */ - -METHODDEF void -grayscale_convert (j_decompress_ptr cinfo, - JSAMPIMAGE input_buf, JDIMENSION input_row, - JSAMPARRAY output_buf, int num_rows) -{ - jcopy_sample_rows(input_buf[0], (int) input_row, output_buf, 0, - num_rows, cinfo->output_width); -} - - -/* - * Adobe-style YCCK->CMYK conversion. - * We convert YCbCr to R=1-C, G=1-M, and B=1-Y using the same - * conversion as above, while passing K (black) unchanged. - * We assume build_ycc_rgb_table has been called. - */ - -METHODDEF void -ycck_cmyk_convert (j_decompress_ptr cinfo, - JSAMPIMAGE input_buf, JDIMENSION input_row, - JSAMPARRAY output_buf, int num_rows) -{ - my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; - register int y, cb, cr; - register JSAMPROW outptr; - register JSAMPROW inptr0, inptr1, inptr2, inptr3; - register JDIMENSION col; - JDIMENSION num_cols = cinfo->output_width; - /* copy these pointers into registers if possible */ - register JSAMPLE * range_limit = cinfo->sample_range_limit; - register int * Crrtab = cconvert->Cr_r_tab; - register int * Cbbtab = cconvert->Cb_b_tab; - register INT32 * Crgtab = cconvert->Cr_g_tab; - register INT32 * Cbgtab = cconvert->Cb_g_tab; - SHIFT_TEMPS - - while (--num_rows >= 0) { - inptr0 = input_buf[0][input_row]; - inptr1 = input_buf[1][input_row]; - inptr2 = input_buf[2][input_row]; - inptr3 = input_buf[3][input_row]; - input_row++; - outptr = *output_buf++; - for (col = 0; col < num_cols; col++) { - y = GETJSAMPLE(inptr0[col]); - cb = GETJSAMPLE(inptr1[col]); - cr = GETJSAMPLE(inptr2[col]); - /* Range-limiting is essential due to noise introduced by DCT losses. */ - outptr[0] = range_limit[MAXJSAMPLE - (y + Crrtab[cr])]; /* red */ - outptr[1] = range_limit[MAXJSAMPLE - (y + /* green */ - ((int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], - SCALEBITS)))]; - outptr[2] = range_limit[MAXJSAMPLE - (y + Cbbtab[cb])]; /* blue */ - /* K passes through unchanged */ - outptr[3] = inptr3[col]; /* don't need GETJSAMPLE here */ - outptr += 4; - } - } -} - - -/* - * Empty method for start_pass. - */ - -METHODDEF void -start_pass_dcolor (j_decompress_ptr cinfo) -{ - /* no work needed */ -} - - -/* - * Module initialization routine for output colorspace conversion. - */ - -GLOBAL void -jinit_color_deconverter (j_decompress_ptr cinfo) -{ - my_cconvert_ptr cconvert; - int ci; - - cconvert = (my_cconvert_ptr) - (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, - SIZEOF(my_color_deconverter)); - cinfo->cconvert = (struct jpeg_color_deconverter *) cconvert; - cconvert->pub.start_pass = start_pass_dcolor; - - /* Make sure num_components agrees with jpeg_color_space */ - switch (cinfo->jpeg_color_space) { - case JCS_GRAYSCALE: - if (cinfo->num_components != 1) - ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); - break; - - case JCS_RGB: - case JCS_YCbCr: - if (cinfo->num_components != 3) - ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); - break; - - case JCS_CMYK: - case JCS_YCCK: - if (cinfo->num_components != 4) - ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); - break; - - default: /* JCS_UNKNOWN can be anything */ - if (cinfo->num_components < 1) - ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); - break; - } - - /* Set out_color_components and conversion method based on requested space. - * Also clear the component_needed flags for any unused components, - * so that earlier pipeline stages can avoid useless computation. - */ - - switch (cinfo->out_color_space) { - case JCS_GRAYSCALE: - cinfo->out_color_components = 1; - if (cinfo->jpeg_color_space == JCS_GRAYSCALE || - cinfo->jpeg_color_space == JCS_YCbCr) { - cconvert->pub.color_convert = grayscale_convert; - /* For color->grayscale conversion, only the Y (0) component is needed */ - for (ci = 1; ci < cinfo->num_components; ci++) - cinfo->comp_info[ci].component_needed = FALSE; - } else - ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); - break; - - case JCS_RGB: - cinfo->out_color_components = RGB_PIXELSIZE; - if (cinfo->jpeg_color_space == JCS_YCbCr) { - cconvert->pub.color_convert = ycc_rgb_convert; - build_ycc_rgb_table(cinfo); - } else if (cinfo->jpeg_color_space == JCS_RGB && RGB_PIXELSIZE == 3) { - cconvert->pub.color_convert = null_convert; - } else - ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); - break; - - case JCS_CMYK: - cinfo->out_color_components = 4; - if (cinfo->jpeg_color_space == JCS_YCCK) { - cconvert->pub.color_convert = ycck_cmyk_convert; - build_ycc_rgb_table(cinfo); - } else if (cinfo->jpeg_color_space == JCS_CMYK) { - cconvert->pub.color_convert = null_convert; - } else - ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); - break; - - default: - /* Permit null conversion to same output space */ - if (cinfo->out_color_space == cinfo->jpeg_color_space) { - cinfo->out_color_components = cinfo->num_components; - cconvert->pub.color_convert = null_convert; - } else /* unsupported non-null conversion */ - ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); - break; - } - - if (cinfo->quantize_colors) - cinfo->output_components = 1; /* single colormapped output component */ - else - cinfo->output_components = cinfo->out_color_components; -} |