jdcolor.c File Reference

#include "jinclude.h"
#include "jpeglib.h"

Include dependency graph for jdcolor.c:

Go to the source code of this file.

Classes
struct	my_color_deconverter

Macros
#define	JPEG_INTERNALS
#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))
#define	R_Y_OFF   0 /* offset to R => Y section */
#define	G_Y_OFF   (1*(MAXJSAMPLE+1)) /* offset to G => Y section */
#define	B_Y_OFF   (2*(MAXJSAMPLE+1)) /* etc. */
#define	TABLE_SIZE   (3*(MAXJSAMPLE+1))

Typedefs
typedef my_color_deconverter *	my_cconvert_ptr

Functions
	build_ycc_rgb_table (j_decompress_ptr cinfo)
	build_bg_ycc_rgb_table (j_decompress_ptr cinfo)
	ycc_rgb_convert (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION input_row, JSAMPARRAY output_buf, int num_rows)
	build_rgb_y_table (j_decompress_ptr cinfo)
	rgb_gray_convert (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION input_row, JSAMPARRAY output_buf, int num_rows)
	rgb1_rgb_convert (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION input_row, JSAMPARRAY output_buf, int num_rows)
	rgb1_gray_convert (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION input_row, JSAMPARRAY output_buf, int num_rows)
	rgb_convert (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION input_row, JSAMPARRAY output_buf, int num_rows)
	null_convert (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION input_row, JSAMPARRAY output_buf, int num_rows)
	grayscale_convert (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION input_row, JSAMPARRAY output_buf, int num_rows)
	gray_rgb_convert (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION input_row, JSAMPARRAY output_buf, int num_rows)
	ycck_cmyk_convert (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION input_row, JSAMPARRAY output_buf, int num_rows)
	start_pass_dcolor (j_decompress_ptr cinfo)
	jinit_color_deconverter (j_decompress_ptr cinfo)

Variables
	Sorry

Macro Definition Documentation

B_Y_OFF

#define B_Y_OFF   (2*(MAXJSAMPLE+1)) /* etc. */

Definition at line 110 of file jdcolor.c.

FIX

#define FIX

(

x

)

((INT32) ((x) * (1L<<SCALEBITS) + 0.5))

Definition at line 99 of file jdcolor.c.

G_Y_OFF

#define G_Y_OFF   (1*(MAXJSAMPLE+1)) /* offset to G => Y section */

Definition at line 109 of file jdcolor.c.

JPEG_INTERNALS

#define JPEG_INTERNALS

Definition at line 12 of file jdcolor.c.

ONE_HALF

#define ONE_HALF   ((INT32) 1 << (SCALEBITS-1))

Definition at line 98 of file jdcolor.c.

R_Y_OFF

#define R_Y_OFF   0 /* offset to R => Y section */

Definition at line 108 of file jdcolor.c.

SCALEBITS

#define SCALEBITS   16 /* speediest right-shift on some machines */

Definition at line 97 of file jdcolor.c.

TABLE_SIZE

#define TABLE_SIZE   (3*(MAXJSAMPLE+1))

Definition at line 111 of file jdcolor.c.

Typedef Documentation

my_cconvert_ptr

typedef my_color_deconverter* my_cconvert_ptr

Definition at line 38 of file jdcolor.c.

Function Documentation

build_bg_ycc_rgb_table()

build_bg_ycc_rgb_table

(

j_decompress_ptr

cinfo

)

Definition at line 153 of file jdcolor.c.

{
  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 2.804 * x */
    cconvert->Cr_r_tab[i] = (int) DESCALE(FIX(2.804) * x, SCALEBITS);
    /* Cb=>B value is nearest int to 3.544 * x */
    cconvert->Cb_b_tab[i] = (int) DESCALE(FIX(3.544) * x, SCALEBITS);
    /* Cr=>G value is scaled-up -1.428272572 * x */
    cconvert->Cr_g_tab[i] = (- FIX(1.428272572)) * x;
    /* Cb=>G value is scaled-up -0.688272572 * x */
    /* We also add in ONE_HALF so that need not do it in inner loop */
    cconvert->Cb_g_tab[i] = (- FIX(0.688272572)) * x + ONE_HALF;
  }
}

Referenced by jinit_color_deconverter().

build_rgb_y_table()

build_rgb_y_table

(

j_decompress_ptr

cinfo

)

Definition at line 249 of file jdcolor.c.

{
  my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
  INT32 * rgb_y_tab;
  INT32 i;
 
  /* Allocate and fill in the conversion tables. */
  cconvert->rgb_y_tab = rgb_y_tab = (INT32 *) (*cinfo->mem->alloc_small)
    ((j_common_ptr) cinfo, JPOOL_IMAGE, TABLE_SIZE * SIZEOF(INT32));
 
  for (i = 0; i <= MAXJSAMPLE; i++) {
    rgb_y_tab[i+R_Y_OFF] = FIX(0.299) * i;
    rgb_y_tab[i+G_Y_OFF] = FIX(0.587) * i;
    rgb_y_tab[i+B_Y_OFF] = FIX(0.114) * i + ONE_HALF;
  }
}

Referenced by jinit_color_deconverter().

build_ycc_rgb_table()

build_ycc_rgb_table

(

j_decompress_ptr

cinfo

)

Definition at line 119 of file jdcolor.c.

{
  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 1.402 * x */
    cconvert->Cr_r_tab[i] = (int) DESCALE(FIX(1.402) * x, SCALEBITS);
    /* Cb=>B value is nearest int to 1.772 * x */
    cconvert->Cb_b_tab[i] = (int) DESCALE(FIX(1.772) * x, SCALEBITS);
    /* Cr=>G value is scaled-up -0.714136286 * x */
    cconvert->Cr_g_tab[i] = (- FIX(0.714136286)) * x;
    /* Cb=>G value is scaled-up -0.344136286 * x */
    /* We also add in ONE_HALF so that need not do it in inner loop */
    cconvert->Cb_g_tab[i] = (- FIX(0.344136286)) * x + ONE_HALF;
  }
}

Referenced by jinit_color_deconverter().

gray_rgb_convert()

gray_rgb_convert	(	j_decompress_ptr	cinfo,
		JSAMPIMAGE	input_buf,
		JDIMENSION	input_row,
		JSAMPARRAY	output_buf,
		int	num_rows
	)

Definition at line 477 of file jdcolor.c.

{
  register JSAMPROW outptr;
  register JSAMPROW inptr;
  register JDIMENSION col;
  JDIMENSION num_cols = cinfo->output_width;
 
  while (--num_rows >= 0) {
    inptr = input_buf[0][input_row++];
    outptr = *output_buf++;
    for (col = 0; col < num_cols; col++) {
      /* We can dispense with GETJSAMPLE() here */
      outptr[RGB_RED] = outptr[RGB_GREEN] = outptr[RGB_BLUE] = inptr[col];
      outptr += RGB_PIXELSIZE;
    }
  }
}

Referenced by jinit_color_deconverter().

grayscale_convert()

grayscale_convert	(	j_decompress_ptr	cinfo,
		JSAMPIMAGE	input_buf,
		JDIMENSION	input_row,
		JSAMPARRAY	output_buf,
		int	num_rows
	)

Definition at line 461 of file jdcolor.c.

{
  jcopy_sample_rows(input_buf[0], (int) input_row, output_buf, 0,
            num_rows, cinfo->output_width);
}

Referenced by jinit_color_deconverter().

jinit_color_deconverter()

jinit_color_deconverter

(

j_decompress_ptr

cinfo

)

Definition at line 568 of file jdcolor.c.

{
  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 = &cconvert->pub;
  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:
  case JCS_BG_RGB:
  case JCS_BG_YCC:
    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);
  }
 
  /* Support color transform only for RGB colorspaces */
  if (cinfo->color_transform &&
      cinfo->jpeg_color_space != JCS_RGB &&
      cinfo->jpeg_color_space != JCS_BG_RGB)
    ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
 
  /* 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;
    switch (cinfo->jpeg_color_space) {
    case JCS_GRAYSCALE:
    case JCS_YCbCr:
    case JCS_BG_YCC:
      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;
      break;
    case JCS_RGB:
      switch (cinfo->color_transform) {
      case JCT_NONE:
    cconvert->pub.color_convert = rgb_gray_convert;
    break;
      case JCT_SUBTRACT_GREEN:
    cconvert->pub.color_convert = rgb1_gray_convert;
    break;
      default:
    ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
      }
      build_rgb_y_table(cinfo);
      break;
    default:
      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
    }
    break;
 
  case JCS_RGB:
    cinfo->out_color_components = RGB_PIXELSIZE;
    switch (cinfo->jpeg_color_space) {
    case JCS_GRAYSCALE:
      cconvert->pub.color_convert = gray_rgb_convert;
      break;
    case JCS_YCbCr:
      cconvert->pub.color_convert = ycc_rgb_convert;
      build_ycc_rgb_table(cinfo);
      break;
    case JCS_BG_YCC:
      cconvert->pub.color_convert = ycc_rgb_convert;
      build_bg_ycc_rgb_table(cinfo);
      break;
    case JCS_RGB:
      switch (cinfo->color_transform) {
      case JCT_NONE:
    cconvert->pub.color_convert = rgb_convert;
    break;
      case JCT_SUBTRACT_GREEN:
    cconvert->pub.color_convert = rgb1_rgb_convert;
    break;
      default:
    ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
      }
      break;
    default:
      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
    }
    break;
 
  case JCS_BG_RGB:
    cinfo->out_color_components = RGB_PIXELSIZE;
    if (cinfo->jpeg_color_space != JCS_BG_RGB)
      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
    switch (cinfo->color_transform) {
    case JCT_NONE:
      cconvert->pub.color_convert = rgb_convert;
      break;
    case JCT_SUBTRACT_GREEN:
      cconvert->pub.color_convert = rgb1_rgb_convert;
      break;
    default:
      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
    }
    break;
 
  case JCS_CMYK:
    cinfo->out_color_components = 4;
    switch (cinfo->jpeg_color_space) {
    case JCS_YCCK:
      cconvert->pub.color_convert = ycck_cmyk_convert;
      build_ycc_rgb_table(cinfo);
      break;
    case JCS_CMYK:
      cconvert->pub.color_convert = null_convert;
      break;
    default:
      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
    }
    break;
 
  default:      /* permit null conversion to same output space */
    if (cinfo->out_color_space != cinfo->jpeg_color_space)
      /* unsupported non-null conversion */
      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
    cinfo->out_color_components = cinfo->num_components;
    cconvert->pub.color_convert = null_convert;
  }
 
  if (cinfo->quantize_colors)
    cinfo->output_components = 1; /* single colormapped output component */
  else
    cinfo->output_components = cinfo->out_color_components;
}

Referenced by master_selection().

null_convert()

null_convert	(	j_decompress_ptr	cinfo,
		JSAMPIMAGE	input_buf,
		JDIMENSION	input_row,
		JSAMPARRAY	output_buf,
		int	num_rows
	)

Definition at line 427 of file jdcolor.c.

{
  register JSAMPROW outptr;
  register JSAMPROW inptr;
  register JDIMENSION count;
  register int num_comps = cinfo->num_components;
  JDIMENSION num_cols = cinfo->output_width;
  int ci;
 
  while (--num_rows >= 0) {
    /* It seems fastest to make a separate pass for each component. */
    for (ci = 0; ci < num_comps; ci++) {
      inptr = input_buf[ci][input_row];
      outptr = output_buf[0] + ci;
      for (count = num_cols; count > 0; count--) {
    *outptr = *inptr++; /* don't need GETJSAMPLE() here */
    outptr += num_comps;
      }
    }
    input_row++;
    output_buf++;
  }
}

Referenced by jinit_color_deconverter().

rgb1_gray_convert()

rgb1_gray_convert	(	j_decompress_ptr	cinfo,
		JSAMPIMAGE	input_buf,
		JDIMENSION	input_row,
		JSAMPARRAY	output_buf,
		int	num_rows
	)

Definition at line 351 of file jdcolor.c.

{
  my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
  register int r, g, b;
  register INT32 * ctab = cconvert->rgb_y_tab;
  register JSAMPROW outptr;
  register JSAMPROW inptr0, inptr1, inptr2;
  register JDIMENSION col;
  JDIMENSION num_cols = cinfo->output_width;
 
  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++) {
      r = GETJSAMPLE(inptr0[col]);
      g = GETJSAMPLE(inptr1[col]);
      b = GETJSAMPLE(inptr2[col]);
      /* Assume that MAXJSAMPLE+1 is a power of 2, so that the MOD
       * (modulo) operator is equivalent to the bitmask operator AND.
       */
      r = (r + g - CENTERJSAMPLE) & MAXJSAMPLE;
      b = (b + g - CENTERJSAMPLE) & MAXJSAMPLE;
      /* Y */
      outptr[col] = (JSAMPLE)
        ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])
         >> SCALEBITS);
    }
  }
}

Referenced by jinit_color_deconverter().

rgb1_rgb_convert()

rgb1_rgb_convert	(	j_decompress_ptr	cinfo,
		JSAMPIMAGE	input_buf,
		JDIMENSION	input_row,
		JSAMPARRAY	output_buf,
		int	num_rows
	)

Definition at line 313 of file jdcolor.c.

{
  register int r, g, b;
  register JSAMPROW outptr;
  register JSAMPROW inptr0, inptr1, inptr2;
  register JDIMENSION col;
  JDIMENSION num_cols = cinfo->output_width;
 
  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++) {
      r = GETJSAMPLE(inptr0[col]);
      g = GETJSAMPLE(inptr1[col]);
      b = GETJSAMPLE(inptr2[col]);
      /* Assume that MAXJSAMPLE+1 is a power of 2, so that the MOD
       * (modulo) operator is equivalent to the bitmask operator AND.
       */
      outptr[RGB_RED]   = (JSAMPLE) ((r + g - CENTERJSAMPLE) & MAXJSAMPLE);
      outptr[RGB_GREEN] = (JSAMPLE) g;
      outptr[RGB_BLUE]  = (JSAMPLE) ((b + g - CENTERJSAMPLE) & MAXJSAMPLE);
      outptr += RGB_PIXELSIZE;
    }
  }
}

Referenced by jinit_color_deconverter().

rgb_convert()

rgb_convert	(	j_decompress_ptr	cinfo,
		JSAMPIMAGE	input_buf,
		JDIMENSION	input_row,
		JSAMPARRAY	output_buf,
		int	num_rows
	)

Definition at line 394 of file jdcolor.c.

{
  register JSAMPROW outptr;
  register JSAMPROW inptr0, inptr1, inptr2;
  register JDIMENSION col;
  JDIMENSION num_cols = cinfo->output_width;
 
  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++) {
      /* We can dispense with GETJSAMPLE() here */
      outptr[RGB_RED]   = inptr0[col];
      outptr[RGB_GREEN] = inptr1[col];
      outptr[RGB_BLUE]  = inptr2[col];
      outptr += RGB_PIXELSIZE;
    }
  }
}

Referenced by jinit_color_deconverter().

rgb_gray_convert()

rgb_gray_convert	(	j_decompress_ptr	cinfo,
		JSAMPIMAGE	input_buf,
		JDIMENSION	input_row,
		JSAMPARRAY	output_buf,
		int	num_rows
	)

Definition at line 272 of file jdcolor.c.

{
  my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
  register int r, g, b;
  register INT32 * ctab = cconvert->rgb_y_tab;
  register JSAMPROW outptr;
  register JSAMPROW inptr0, inptr1, inptr2;
  register JDIMENSION col;
  JDIMENSION num_cols = cinfo->output_width;
 
  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++) {
      r = GETJSAMPLE(inptr0[col]);
      g = GETJSAMPLE(inptr1[col]);
      b = GETJSAMPLE(inptr2[col]);
      /* Y */
      outptr[col] = (JSAMPLE)
        ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])
         >> SCALEBITS);
    }
  }
}

Referenced by jinit_color_deconverter().

start_pass_dcolor()

start_pass_dcolor

(

j_decompress_ptr

cinfo

)

Definition at line 557 of file jdcolor.c.

{
  /* no work needed */
}

Referenced by jinit_color_deconverter().

ycc_rgb_convert()

ycc_rgb_convert	(	j_decompress_ptr	cinfo,
		JSAMPIMAGE	input_buf,
		JDIMENSION	input_row,
		JSAMPARRAY	output_buf,
		int	num_rows
	)

Definition at line 199 of file jdcolor.c.

{
  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,
       * for extended gamut (sYCC) and wide gamut (bg-sYCC) encodings.
       */
      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;
    }
  }
}

Referenced by jinit_color_deconverter().

ycck_cmyk_convert()

ycck_cmyk_convert	(	j_decompress_ptr	cinfo,
		JSAMPIMAGE	input_buf,
		JDIMENSION	input_row,
		JSAMPARRAY	output_buf,
		int	num_rows
	)

Definition at line 507 of file jdcolor.c.

{
  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,
       * and for extended gamut encodings (sYCC).
       */
      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;
    }
  }
}

Referenced by jinit_color_deconverter().

Variable Documentation

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Definition at line 19 of file jdcolor.c.