op_c.c File Reference

#include <assert.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <math.h>
#include "op_c.h"
#include "errors.h"
#include "colorred.h"
#include "global.h"
#include <limits.h>
#include "engine.h"
#include "windows.h"

Include dependency graph for op_c.c:

Macros
#define	GRAFX2_QUANTIZE_CLUSTER_POPULATION_SPLIT

Functions
void	RGB_to_HSL (int r, int g, int b, byte *hr, byte *sr, byte *lr)
	Convert RGB to HSL. More...
void	HSL_to_RGB (byte h, byte s, byte l, byte *r, byte *g, byte *b)
	Convert HSL back to RGB Input and output are all in range 0..255. More...
long	Perceptual_lightness (T_Components *color)
	Returns a value that is high when color is near white, and low when it's darker. More...
void	OT_init (T_Occurrence_table *t)
	Initialize an occurrence table. More...
T_Occurrence_table *	OT_new (int nbb_r, int nbb_g, int nbb_b)
	Allocate an occurrence table for given number of bits. More...
void	OT_delete (T_Occurrence_table *t)
	Delete a table and free the memory. More...
int	OT_get (T_Occurrence_table *t, byte r, byte g, byte b)
	Get number of occurrences for a given color. More...
void	OT_inc (T_Occurrence_table *t, byte r, byte g, byte b)
	Add 1 to the count for a color. More...
void	OT_count_occurrences (T_Occurrence_table *t, T_Bitmap24B image, int size)
	Count the use of each color in a 24bit picture and fill in the table. More...
int	OT_count_colors (T_Occurrence_table *t)
	Count the total number of pixels in an occurrence table. More...
void	Cluster_pack (T_Cluster *c, const T_Occurrence_table *const to)
	Pack a cluster, ie compute its {r,v,b}{min,max} values. More...
void	Cluster_split (T_Cluster *c, T_Cluster *c1, T_Cluster *c2, int hue, const T_Occurrence_table *const to)
	Split a cluster on its longest axis. More...
void	Cluster_compute_hue (T_Cluster *c, T_Occurrence_table *to)
	Compute the mean R, G, B (for palette generation) and H, L (for palette sorting) More...
void	CT_set_trad (CT_Tree *colorTree, byte Rmin, byte Gmin, byte Bmin, byte Rmax, byte Gmax, byte Bmax, byte index, const T_Occurrence_table *to)
void	CS_Init (T_Cluster_set *cs, T_Occurrence_table *to)
	Setup the first cluster before we start the operations This one covers the full palette range. More...
T_Cluster_set *	CS_New (int nbmax, T_Occurrence_table *to)
	Allocate a new cluster set. More...
void	CS_Delete (T_Cluster_set *cs)
	Free a cluster set. More...
void	CS_Get (T_Cluster_set *cs, T_Cluster **c)
	Pop a cluster from the cluster list. More...
int	CS_Set (T_Cluster_set *cs, T_Cluster *c)
	Push a copy of a cluster in the list return -1 in case of error. More...
int	CS_Generate (T_Cluster_set *cs, const T_Occurrence_table *const to, CT_Tree *colorTree)
	This is the main median cut algorithm and the function actually called to reduce the palette. More...
void	CS_Compute_colors (T_Cluster_set *cs, T_Occurrence_table *to)
	Compute the color associated to each box in the list. More...
void	CS_Sort_by_chrominance (T_Cluster_set *cs)
	Sort the clusters by chrominance value. More...
void	CS_Sort_by_luminance (T_Cluster_set *cs)
	Sort the clusters by luminance value. More...
void	CS_Generate_color_table_and_palette (T_Cluster_set *cs, CT_Tree *tc, T_Components *palette, T_Occurrence_table *to)
	Generates the palette from the clusters, then the conversion table to map (RGB) to a palette index. More...
void	GS_Init (T_Gradient_set *ds, T_Cluster_set *cs)
T_Gradient_set *	GS_New (T_Cluster_set *cs)
void	GS_Delete (T_Gradient_set *ds)
void	GS_Generate (T_Gradient_set *ds, T_Cluster_set *cs)
CT_Tree *	Optimize_palette (T_Bitmap24B image, int size, T_Components *palette, int r, int g, int b)
	Compute best palette for given picture. More...
int	Modified_value (int value, int modif)
	Change a value with proper ceiling and flooring. More...
void	Convert_24b_bitmap_to_256_Floyd_Steinberg (T_Bitmap256 dest, T_Bitmap24B source, int width, int height, T_Components *palette, CT_Tree *tc)
	Convert a 24b image to 256 colors (with a given palette and conversion table). More...
void	Convert_24b_bitmap_to_256_nearest_neighbor (T_Bitmap256 dest, T_Bitmap24B source, int width, int height, T_Components *palette, CT_Tree *tc)
	Converts from 24b to 256c without dithering, using given conversion table. More...
int	Try_Convert_to_256_Without_Loss (T_Bitmap256 dest, T_Bitmap24B source, int width, int height, T_Components *palette)
int	Convert_24b_bitmap_to_256 (T_Bitmap256 dest, T_Bitmap24B source, int width, int height, T_Components *palette)
	Converts a 24 bit picture to 256 color (color reduction) More...
void	Set_palette_fake_24b (T_Palette palette)

Variables
static const byte	precision_24b []

Macro Definition Documentation

GRAFX2_QUANTIZE_CLUSTER_POPULATION_SPLIT

#define GRAFX2_QUANTIZE_CLUSTER_POPULATION_SPLIT

Function Documentation

RGB_to_HSL()

void RGB_to_HSL	(	int	r,
		int	g,
		int	b,
		byte *	hr,
		byte *	sr,
		byte *	lr
	)

Convert RGB to HSL.

Both input and output are in the 0..255 range to use in the palette screen

Referenced by Button_Palette(), Cluster_compute_hue(), Compute_optimal_menu_colors(), Display_sliders(), Draw_all_palette_sliders(), and Set_HSL().

HSL_to_RGB()

void HSL_to_RGB	(	byte	h,
		byte	s,
		byte	l,
		byte *	r,
		byte *	g,
		byte *	b
	)

Convert HSL back to RGB Input and output are all in range 0..255.

Referenced by Button_Palette(), and Set_HSL().

Perceptual_lightness()

long Perceptual_lightness

(

T_Components *

color

)

Returns a value that is high when color is near white, and low when it's darker.

Used for sorting.

References T_Components::B, T_Components::G, and T_Components::R.

Referenced by Button_Palette().

OT_init()

void OT_init

(

T_Occurrence_table *

t

)

Initialize an occurrence table.

References T_Occurrence_table::rng_b, T_Occurrence_table::rng_g, T_Occurrence_table::rng_r, and T_Occurrence_table::table.

OT_new()

T_Occurrence_table * OT_new	(	int	nbb_r,
		int	nbb_g,
		int	nbb_b
	)

Allocate an occurrence table for given number of bits.

References T_Occurrence_table::dec_b, T_Occurrence_table::dec_g, T_Occurrence_table::dec_r, T_Occurrence_table::nbb_b, T_Occurrence_table::nbb_g, T_Occurrence_table::nbb_r, NULL, T_Occurrence_table::red_b, T_Occurrence_table::red_g, T_Occurrence_table::red_r, T_Occurrence_table::rng_b, T_Occurrence_table::rng_g, T_Occurrence_table::rng_r, and T_Occurrence_table::table.

Referenced by Optimize_palette().

OT_delete()

void OT_delete

(

T_Occurrence_table *

t

)

Delete a table and free the memory.

References NULL, and T_Occurrence_table::table.

Referenced by Optimize_palette().

OT_get()

int OT_get	(	T_Occurrence_table *	t,
		byte	r,
		byte	g,
		byte	b
	)

Get number of occurrences for a given color.

References T_Occurrence_table::dec_b, T_Occurrence_table::dec_g, T_Occurrence_table::dec_r, and T_Occurrence_table::table.

Referenced by Cluster_compute_hue().

OT_inc()

void OT_inc	(	T_Occurrence_table *	t,
		byte	r,
		byte	g,
		byte	b
	)

Add 1 to the count for a color.

References T_Occurrence_table::dec_b, T_Occurrence_table::dec_g, T_Occurrence_table::dec_r, T_Occurrence_table::red_b, T_Occurrence_table::red_g, T_Occurrence_table::red_r, and T_Occurrence_table::table.

Referenced by OT_count_occurrences().

OT_count_occurrences()

void OT_count_occurrences	(	T_Occurrence_table *	t,
		T_Bitmap24B	image,
		int	size
	)

Count the use of each color in a 24bit picture and fill in the table.

References T_Components::B, T_Components::G, OT_inc(), and T_Components::R.

Referenced by Optimize_palette().

OT_count_colors()

int OT_count_colors

(

T_Occurrence_table *

t

)

Count the total number of pixels in an occurrence table.

References T_Occurrence_table::rng_b, T_Occurrence_table::rng_g, T_Occurrence_table::rng_r, and T_Occurrence_table::table.

Referenced by CS_New().

Cluster_pack()

void Cluster_pack	(	T_Cluster *	c,
		const T_Occurrence_table *const	to
	)

Pack a cluster, ie compute its {r,v,b}{min,max} values.

References T_Cluster::bmax, T_Cluster::bmin, U_Cluster_Data::cut, T_Cluster::data, T_Occurrence_table::dec_b, T_Occurrence_table::dec_g, T_Occurrence_table::dec_r, T_Cluster::occurences, S_Cluster_CutData::plus_large, T_Cluster::rmax, T_Cluster::rmin, S_Cluster_CutData::sqdiag, T_Occurrence_table::table, T_Cluster::vmax, T_Cluster::vmin, and S_Cluster_CutData::volume.

Referenced by CS_Generate(), and CS_Init().

Cluster_split()

void Cluster_split	(	T_Cluster *	c,
		T_Cluster *	c1,
		T_Cluster *	c2,
		int	hue,
		const T_Occurrence_table *const	to
	)

Split a cluster on its longest axis.

c = source cluster, c1, c2 = output after split the two output clusters have half population (and not half volume)

References T_Cluster::bmax, T_Cluster::Bmax, T_Cluster::bmin, T_Cluster::Bmin, T_Cluster::Gmin, T_Cluster::occurences, T_Cluster::rmax, T_Cluster::Rmax, T_Cluster::rmin, T_Cluster::Rmin, T_Cluster::vmax, T_Cluster::Vmax, and T_Cluster::vmin.

Referenced by CS_Generate().

Cluster_compute_hue()

void Cluster_compute_hue	(	T_Cluster *	c,
		T_Occurrence_table *	to
	)

Compute the mean R, G, B (for palette generation) and H, L (for palette sorting)

References S_Cluster_PalData::b, T_Cluster::bmin, T_Cluster::data, S_Cluster_PalData::g, S_Cluster_PalData::h, S_Cluster_PalData::l, T_Cluster::occurences, OT_get(), U_Cluster_Data::pal, S_Cluster_PalData::r, T_Occurrence_table::red_b, T_Occurrence_table::red_g, T_Occurrence_table::red_r, RGB_to_HSL(), T_Cluster::rmin, and T_Cluster::vmin.

Referenced by CS_Compute_colors().

CT_set_trad()

void CT_set_trad	(	CT_Tree *	colorTree,
		byte	Rmin,
		byte	Gmin,
		byte	Bmin,
		byte	Rmax,
		byte	Gmax,
		byte	Bmax,
		byte	index,
		const T_Occurrence_table *	to
	)

References CT_set(), T_Occurrence_table::red_b, T_Occurrence_table::red_g, and T_Occurrence_table::red_r.

Referenced by CS_Generate(), and CS_Generate_color_table_and_palette().

CS_Init()

void CS_Init	(	T_Cluster_set *	cs,
		T_Occurrence_table *	to
	)

Setup the first cluster before we start the operations This one covers the full palette range.

References T_Cluster::bmax, T_Cluster::Bmax, T_Cluster::bmin, T_Cluster::Bmin, Cluster_pack(), T_Cluster_set::clusters, T_Cluster::Gmin, T_Cluster_set::nb, T_Cluster::next, NULL, T_Cluster::rmax, T_Cluster::Rmax, T_Cluster::rmin, T_Cluster::Rmin, T_Occurrence_table::rng_b, T_Occurrence_table::rng_g, T_Occurrence_table::rng_r, T_Cluster::vmax, T_Cluster::Vmax, and T_Cluster::vmin.

Referenced by CS_New().

CS_New()

T_Cluster_set * CS_New	(	int	nbmax,
		T_Occurrence_table *	to
	)

Allocate a new cluster set.

References T_Cluster_set::clusters, CS_Init(), T_Cluster_set::nb_max, NULL, and OT_count_colors().

Referenced by Optimize_palette().

CS_Delete()

void CS_Delete

(

T_Cluster_set *

cs

)

Free a cluster set.

References T_Cluster_set::clusters, T_Cluster::next, and NULL.

Referenced by Optimize_palette().

CS_Get()

void CS_Get	(	T_Cluster_set *	cs,
		T_Cluster **	c
	)

Pop a cluster from the cluster list.

References T_Cluster_set::clusters, T_Cluster_set::nb, and T_Cluster::next.

Referenced by CS_Generate().

CS_Set()

int CS_Set	(	T_Cluster_set *	cs,
		T_Cluster *	c
	)

Push a copy of a cluster in the list return -1 in case of error.

References T_Cluster_set::clusters, U_Cluster_Data::cut, T_Cluster::data, T_Cluster_set::nb, T_Cluster::next, NULL, S_Cluster_CutData::sqdiag, and S_Cluster_CutData::volume.

Referenced by CS_Generate().

CS_Generate()

int CS_Generate	(	T_Cluster_set *	cs,
		const T_Occurrence_table *const	to,
		CT_Tree *	colorTree
	)

This is the main median cut algorithm and the function actually called to reduce the palette.

We get the number of pixels for each collor in the occurrence table and generate the cluster set from it.

References T_Cluster::Bmax, T_Cluster::Bmin, Cluster_pack(), Cluster_split(), CS_Get(), CS_Set(), CT_set_trad(), U_Cluster_Data::cut, T_Cluster::data, T_Cluster::Gmin, T_Cluster_set::nb, T_Cluster_set::nb_max, T_Cluster::occurences, S_Cluster_CutData::plus_large, T_Cluster::Rmax, T_Cluster::Rmin, T_Cluster::Vmax, and S_Cluster_CutData::volume.

Referenced by Optimize_palette().

CS_Compute_colors()

void CS_Compute_colors	(	T_Cluster_set *	cs,
		T_Occurrence_table *	to
	)

Compute the color associated to each box in the list.

References Cluster_compute_hue(), T_Cluster_set::clusters, T_Cluster::next, and NULL.

Referenced by Optimize_palette().

CS_Sort_by_chrominance()

void CS_Sort_by_chrominance

(

T_Cluster_set *

cs

)

Sort the clusters by chrominance value.

References T_Cluster_set::clusters, T_Cluster::data, S_Cluster_PalData::h, T_Cluster::next, NULL, and U_Cluster_Data::pal.

Referenced by Optimize_palette().

CS_Sort_by_luminance()

void CS_Sort_by_luminance

(

T_Cluster_set *

cs

)

Sort the clusters by luminance value.

References T_Cluster_set::clusters, T_Cluster::data, S_Cluster_PalData::l, T_Cluster::next, NULL, and U_Cluster_Data::pal.

Referenced by Optimize_palette().

CS_Generate_color_table_and_palette()

void CS_Generate_color_table_and_palette	(	T_Cluster_set *	cs,
		CT_Tree *	tc,
		T_Components *	palette,
		T_Occurrence_table *	to
	)

Generates the palette from the clusters, then the conversion table to map (RGB) to a palette index.

References S_Cluster_PalData::b, T_Components::B, T_Cluster::Bmax, T_Cluster::Bmin, T_Cluster_set::clusters, CT_set_trad(), T_Cluster::data, S_Cluster_PalData::g, T_Components::G, T_Cluster::Gmin, T_Cluster_set::nb, T_Cluster::next, U_Cluster_Data::pal, S_Cluster_PalData::r, T_Components::R, T_Cluster::Rmax, T_Cluster::Rmin, and T_Cluster::Vmax.

Referenced by Optimize_palette().

GS_Init()

void GS_Init	(	T_Gradient_set *	ds,
		T_Cluster_set *	cs
	)

References T_Cluster_set::clusters, T_Cluster::data, T_Gradient_set::gradients, S_Cluster_PalData::h, T_Gradient::hue, T_Gradient::max, T_Gradient::min, T_Gradient_set::nb, T_Gradient::nb_colors, and U_Cluster_Data::pal.

Referenced by GS_New().

GS_New()

T_Gradient_set * GS_New

(

T_Cluster_set *

cs

)

References T_Gradient_set::gradients, GS_Init(), T_Cluster_set::nb_max, T_Gradient_set::nb_max, and NULL.

Referenced by Optimize_palette().

GS_Delete()

void GS_Delete

(

T_Gradient_set *

ds

)

References T_Gradient_set::gradients.

Referenced by Optimize_palette().

GS_Generate()

void GS_Generate	(	T_Gradient_set *	ds,
		T_Cluster_set *	cs
	)

References T_Cluster_set::clusters, T_Cluster::data, T_Gradient_set::gradients, S_Cluster_PalData::h, T_Gradient::hue, id, T_Gradient::max, T_Gradient::min, T_Gradient_set::nb, T_Gradient::nb_colors, T_Cluster::next, and U_Cluster_Data::pal.

Referenced by Optimize_palette().

Optimize_palette()

CT_Tree * Optimize_palette	(	T_Bitmap24B	image,
		int	size,
		T_Components *	palette,
		int	r,
		int	g,
		int	b
	)

Compute best palette for given picture.

The picture is first depth-reduced to the given r,g,b resolution, then the median cut algorithm is used to find 256 colors which are suitable for the given picture.

Returns

a conversion tree to be used for converting the picture to indexed with the generated palette (with or without dithering).

Parameters

image	The true-color image for which the palette needs to be optimized
size	in pixels (number of pixels, the height/width doesn't matter)
palette	pointer to the space where the palette will be stored (256 entries at most)
r	Resolution for red
g	Resolution for green
b	Resolution for blue

References CS_Compute_colors(), CS_Delete(), CS_Generate(), CS_Generate_color_table_and_palette(), CS_New(), CS_Sort_by_chrominance(), CS_Sort_by_luminance(), CT_delete(), CT_new(), GS_Delete(), GS_Generate(), GS_New(), NULL, OT_count_occurrences(), OT_delete(), and OT_new().

Referenced by Convert_24b_bitmap_to_256().

Modified_value()

int Modified_value	(	int	value,
		int	modif
	)

Change a value with proper ceiling and flooring.

Referenced by Convert_24b_bitmap_to_256_Floyd_Steinberg().

Convert_24b_bitmap_to_256_Floyd_Steinberg()

void Convert_24b_bitmap_to_256_Floyd_Steinberg	(	T_Bitmap256	dest,
		T_Bitmap24B	source,
		int	width,
		int	height,
		T_Components *	palette,
		CT_Tree *	tc
	)

Convert a 24b image to 256 colors (with a given palette and conversion table).

This destroys the 24b picture ! Uses floyd steinberg dithering.

References T_Components::B, CT_get(), T_Components::G, Modified_value(), and T_Components::R.

Convert_24b_bitmap_to_256_nearest_neighbor()

void Convert_24b_bitmap_to_256_nearest_neighbor	(	T_Bitmap256	dest,
		T_Bitmap24B	source,
		int	width,
		int	height,
		T_Components *	palette,
		CT_Tree *	tc
	)

Converts from 24b to 256c without dithering, using given conversion table.

References T_Components::B, CT_get(), T_Components::G, and T_Components::R.

Referenced by Convert_24b_bitmap_to_256().

Try_Convert_to_256_Without_Loss()

int Try_Convert_to_256_Without_Loss	(	T_Bitmap256	dest,
		T_Bitmap24B	source,
		int	width,
		int	height,
		T_Components *	palette
	)

References T_Components::B, T_Components::G, and T_Components::R.

Referenced by Convert_24b_bitmap_to_256().

Convert_24b_bitmap_to_256()

int Convert_24b_bitmap_to_256	(	T_Bitmap256	dest,
		T_Bitmap24B	source,
		int	width,
		int	height,
		T_Components *	palette
	)

Converts a 24 bit picture to 256 color (color reduction)

Parameters

[out]	dest	The converted 8bpp picture
[in]	source	the 24bpp picture
[in]	width	the width of the picture
[in]	height	the height of the picture
[out]	palette	the palette of the converted 8bpp picture

Returns

0 for OK, 1 for error

References Convert_24b_bitmap_to_256_nearest_neighbor(), CT_delete(), NULL, Optimize_palette(), precision_24b, and Try_Convert_to_256_Without_Loss().

Referenced by Load_image(), and Test_Convert_24b_bitmap_to_256().

Set_palette_fake_24b()

void Set_palette_fake_24b

(

T_Palette

palette

)

Referenced by Load_image().

Variable Documentation

precision_24b

const byte precision_24b[]

static

Initial value:

=
{
 8,8,8,
 6,6,6,
 6,6,5,
 5,6,5,
 5,5,5,
 5,5,4,
 4,5,4,
 4,4,4,
 4,4,3,
 3,4,3,
 3,3,3,
 3,3,2}

Referenced by Convert_24b_bitmap_to_256().