libvips/libsrc/histograms_lut/tone.c
2007-08-29 16:23:50 +00:00

529 lines
12 KiB
C

/* @(#) Various functions relating to tone curve adjustment.
* @(#)
* @(#) im_tone_build: generate tone curve for adjustment of LabQ image. LUT we
* @(#) make is always 1024 elements, each element is a LabS L value.
* @(#)
* @(#) Base parameters:
* @(#)
* @(#) Lb - black point
* @(#) Lw - white point (both [0,100])
* @(#)
* @(#) Ps - shadow point
* @(#) Pm - mid-tone point
* @(#) Ph - highlight point
* @(#)
* @(#) All 0-1, meaning max of shadow section of curve should be positioned
* @(#) at Lb+Ps(Lw-Lb), etc. Suggest Lb, Lw should be set by histogram
* @(#) analysis to 0.1% and 99.9%; Ps, Pm, Ph should be 0.2, 0.5, 0.8.
* @(#)
* @(#) Main parameters:
* @(#)
* @(#) S - shadow adjustment factor (+/- 30)
* @(#) M - mid-tone adjustment factor (+/- 30)
* @(#) H - highlight adjustment factor (+/- 30)
* @(#)
* @(#) Usage:
* @(#)
* @(#) int
* @(#) im_tone_build(
* @(#) IMAGE *lut,
* @(#) double Lb, double Lw,
* @(#) double Ps, double Pm, double Ph,
* @(#) double S, double M, double H )
* @(#)
* @(#) Returns 0 on success and -1 on error
* @(#)
* @(#) im_ismonotonic: test any LUT for monotonicity --- set out to non-zero
* @(#) if lut is monotonic.
* @(#)
* @(#) Usage:
* @(#)
* @(#) int
* @(#) im_ismonotonic( IMAGE *lut, int *out )
* @(#)
* @(#) Returns 0 on success and -1 on error
* @(#)
* @(#) im_tone_map: map just the L channel of a LabQ or LabS image through
* @(#) a LUT.
* @(#)
* @(#) Usage:
* @(#)
* @(#) int
* @(#) im_tone_map( IMAGE *in, IMAGE *out, IMAGE *lut )
* @(#)
* @(#) Returns 0 on success and -1 on error
* @(#)
* @(#) im_tone_analyse: find the histogram of a LabS or LabQ image and use
* @(#) that to set the Ln and Lw parameters of im_tone_build()
* @(#)
* @(#) Usage:
* @(#)
* @(#) int
* @(#) im_tone_analyse(
* @(#) IMAGE *in,
* @(#) IMAGE *lut,
* @(#) double Ps, double Pm, double Ph,
* @(#) double S, double M, double H )
* @(#)
* @(#) Returns 0 on success and -1 on error
* @(#)
*
* Author: John Cupitt
* Written on: 18/7/1995
* 17/9/96 JC
* - restrictions on Ps, Pm, Ph relaxed
* - restrictions on S, M, H relaxed
* 25/7/01 JC
* - patched for im_extract_band() change
* 11/7/04
* - generalised to im_tone_build_range() ... so you can use it for any
* image ,not just LabS
*/
/*
This file is part of VIPS.
VIPS is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <vips/intl.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <vips/vips.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
/* Parameters for tone curve formation.
*/
typedef struct {
/* Parameters.
*/
double Lb, Lw;
double Ps, Pm, Ph;
double S, M, H;
/* Derived values.
*/
double Ls, Lm, Lh;
} ToneShape;
/* Calculate shadow curve.
*/
static double
shad( ToneShape *ts, double x )
{
double x1 = (x - ts->Lb) / (ts->Ls - ts->Lb);
double x2 = (x - ts->Ls) / (ts->Lm - ts->Ls);
double out;
if( x < ts->Lb )
out = 0;
else if( x < ts->Ls )
out = 3.0 * x1 * x1 - 2.0 * x1 * x1 * x1;
else if( x < ts->Lm )
out = 1.0 - 3.0 * x2 * x2 + 2.0 * x2 * x2 * x2;
else
out = 0;
return( out );
}
/* Calculate mid-tone curve.
*/
static double
mid( ToneShape *ts, double x )
{
double x1 = (x - ts->Ls) / (ts->Lm - ts->Ls);
double x2 = (x - ts->Lm) / (ts->Lh - ts->Lm);
double out;
if( x < ts->Ls )
out = 0;
else if( x < ts->Lm )
out = 3.0 * x1 * x1 - 2.0 * x1 * x1 * x1;
else if( x < ts->Lh )
out = 1.0 - 3.0 * x2 * x2 + 2.0 * x2 * x2 * x2;
else
out = 0;
return( out );
}
/* Calculate highlight curve.
*/
static double
high( ToneShape *ts, double x )
{
double x1 = (x - ts->Lm) / (ts->Lh - ts->Lm);
double x2 = (x - ts->Lh) / (ts->Lw - ts->Lh);
double out;
if( x < ts->Lm )
out = 0;
else if( x < ts->Lh )
out = 3.0 * x1 * x1 - 2.0 * x1 * x1 * x1;
else if( x < ts->Lw )
out = 1.0 - 3.0 * x2 * x2 + 2.0 * x2 * x2 * x2;
else
out = 0;
return( out );
}
/* Generate a point on the tone curve. Everything is 0-100.
*/
static double
tone_curve( ToneShape *ts, double x )
{
double out;
out = x +
ts->S * shad( ts, x ) + ts->M * mid( ts, x ) +
ts->H * high( ts, x );
return( out );
}
int
im_tone_build_range( IMAGE *out,
int in_max, int out_max,
double Lb, double Lw,
double Ps, double Pm, double Ph,
double S, double M, double H )
{
ToneShape *ts = IM_NEW( out, ToneShape );
unsigned short lut[65536];
int i;
/* Check args.
*/
if( !ts || im_outcheck( out ) )
return( -1 );
if( in_max < 0 || in_max > 65535 ||
out_max < 0 || out_max > 65535 ) {
im_error( "im_tone_build",
_( "bad in_max, out_max parameters" ) );
return( -1 );
}
if( Lb < 0 || Lb > 100 || Lw < 0 || Lw > 100 || Lb > Lw ) {
im_error( "im_tone_build", _( "bad Lb, Lw parameters" ) );
return( -1 );
}
if( Ps < 0.0 || Ps > 1.0 ) {
im_error( "im_tone_build", _( "Ps not in range [0.0,1.0]" ) );
return( -1 );
}
if( Pm < 0.0 || Pm > 1.0 ) {
im_error( "im_tone_build", _( "Pm not in range [0.0,1.0]" ) );
return( -1 );
}
if( Ph < 0.0 || Ph > 1.0 ) {
im_error( "im_tone_build", _( "Ph not in range [0.0,1.0]" ) );
return( -1 );
}
if( S < -30 || S > 30 ) {
im_error( "im_tone_build", _( "S not in range [-30,+30]" ) );
return( -1 );
}
if( M < -30 || M > 30 ) {
im_error( "im_tone_build", _( "M not in range [-30,+30]" ) );
return( -1 );
}
if( H < -30 || H > 30 ) {
im_error( "im_tone_build", _( "H not in range [-30,+30]" ) );
return( -1 );
}
/* Note params.
*/
ts->Lb = Lb;
ts->Lw = Lw;
ts->Ps = Ps;
ts->Pm = Pm;
ts->Ph = Ph;
ts->S = S;
ts->M = M;
ts->H = H;
/* Note derived params.
*/
ts->Ls = Lb + Ps * (Lw - Lb);
ts->Lm = Lb + Pm * (Lw - Lb);
ts->Lh = Lb + Ph * (Lw - Lb);
/* Generate curve.
*/
for( i = 0; i <= in_max; i++ ) {
int v = (out_max / 100.0) *
tone_curve( ts, 100.0 * i / in_max );
if( v < 0 )
v = 0;
else if( v > out_max )
v = out_max;
lut[i] = v;
}
/* Make the output image.
*/
im_initdesc( out,
in_max + 1, 1, 1, IM_BBITS_SHORT, IM_BANDFMT_USHORT,
IM_CODING_NONE, IM_TYPE_HISTOGRAM, 1.0, 1.0, 0, 0 );
if( im_setupout( out ) )
return( -1 );
if( im_writeline( 0, out, (PEL *) lut ) )
return( -1 );
return( 0 );
}
int
im_tone_build( IMAGE *out,
double Lb, double Lw,
double Ps, double Pm, double Ph,
double S, double M, double H )
{
IMAGE *t1 = im_open_local( out, "im_tone_build", "p" );
if( !t1 ||
im_tone_build_range( t1, 1023, 32767,
Lb, Lw, Ps, Pm, Ph, S, M, H ) ||
im_clip2s( t1, out ) )
return( -1 );
return( 0 );
}
/* Test a lut or histogram for monotonicity.
*/
int
im_ismonotonic( IMAGE *lut, int *out )
{
IMAGE *t1 = im_open_local( lut, "im_ismonotonic:1", "p" );
IMAGE *t2 = im_open_local( lut, "im_ismonotonic:2", "p" );
IMAGE *t3 = im_open_local( lut, "im_ismonotonic:3", "p" );
double m;
if( !t1 || !t2 || !t3 )
return( -1 );
/* Can be either a horizontal or vertical LUT.
*/
if( lut->Xsize != 1 && lut->Ysize != 1 ) {
im_error( "im_ismonotonic", _( "not 1 by n or n by 1 image" ) );
return( -1 );
}
/* Extract two areas, offset by 1 pixel.
*/
if( lut->Xsize == 1 ) {
if( im_extract_area( lut, t1, 0, 0, 1, lut->Ysize - 1 ) ||
im_extract_area( lut, t2, 0, 1, 1, lut->Ysize - 1 ) )
return( -1 );
}
else {
if( im_extract_area( lut, t1, 0, 0, lut->Xsize - 1, 1 ) ||
im_extract_area( lut, t2, 1, 0, lut->Xsize - 1, 1 ) )
return( -1 );
}
/* Now t2 should be >= than t1 everywhere!
*/
if( im_moreeq( t2, t1, t3 ) || im_min( t3, &m ) )
return( -1 );
*out = m;
return( 0 );
}
/* Map the L channel of a LabQ or LabS channel of an image through a LUT.
*/
int
im_tone_map( IMAGE *in, IMAGE *out, IMAGE *lut )
{
IMAGE *t1 = im_open_local( out, "im_tone_map:1", "p" );
IMAGE *t2 = im_open_local( out, "im_tone_map:2", "p" );
IMAGE *t3 = im_open_local( out, "im_tone_map:3", "p" );
IMAGE *t4 = im_open_local( out, "im_tone_map:4", "p" );
IMAGE *t5 = im_open_local( out, "im_tone_map:5", "p" );
IMAGE *t6 = im_open_local( out, "im_tone_map:6", "p" );
IMAGE *t7 = im_open_local( out, "im_tone_map:7", "p" );
IMAGE *t8 = im_open_local( out, "im_tone_map:8", "p" );
IMAGE *imarray[3];
if( !t1 || !t2 || !t3 || !t4 || !t5 || !t6 || !t7 )
return( -1 );
/* Need a 1024-point IM_BANDFMT_SHORT lut.
*/
if( lut->Xsize != 1 && lut->Ysize != 1 ) {
im_error( "im_tone_map", _( "not 1 by n or n by 1 image" ) );
return( -1 );
}
if( lut->Xsize*lut->Ysize != 1024 ||
lut->BandFmt != IM_BANDFMT_SHORT ) {
im_error( "im_tone_map",
_( "not 1024-point IM_BANDFMT_SHORT lut" ) );
return( -1 );
}
/* If in is IM_CODING_LABQ, unpack.
*/
if( in->Coding == IM_CODING_LABQ ) {
if( im_LabQ2LabS( in, t1 ) )
return( -1 );
}
else
t1 = in;
/* Should now be 3-band short.
*/
if( t1->Coding != IM_CODING_NONE || t1->BandFmt != IM_BANDFMT_SHORT ||
t1->Bands != 3 ) {
im_error( "im_tone_map", _( "input not LabS or LabQ" ) );
return( -1 );
}
/* Split into bands.
*/
if( im_extract_band( t1, t2, 0 ) || im_extract_band( t1, t3, 1 ) ||
im_extract_band( t1, t4, 2 ) )
return( -1 );
/* Scale L down to 10 bits so we can use it to index LUT. And amke
* sure we have an unsigned type we can use for indexing.
*/
if( im_shiftright( t2, t8, 5 ) ||
im_clip2us( t8, t5 ) )
return( -1 );
/* Replace L.
*/
if( im_maplut( t5, t6, lut ) )
return( -1 );
/* Recombine bands. If input was LabQ, repack.
*/
imarray[0] = t6; imarray[1] = t3; imarray[2] = t4;
if( in->Coding == IM_CODING_LABQ ) {
if( im_gbandjoin( imarray, t7, 3 ) ||
im_LabS2LabQ( t7, out ) )
return( -1 );
}
else {
if( im_gbandjoin( imarray, out, 3 ) )
return( -1 );
}
return( 0 );
}
/* Find histogram of in, and use that to set Lb, Lw levels.
*/
int
im_tone_analyse(
IMAGE *in,
IMAGE *lut,
double Ps, double Pm, double Ph,
double S, double M, double H )
{
gint64 sum = in->Xsize * in->Ysize;
int *p;
int i, j;
double Lb, Lw;
IMAGE *t1 = im_open_local( lut, "im_tone_analyse:1", "p" );
IMAGE *t2 = im_open_local( lut, "im_tone_analyse:2", "p" );
IMAGE *t3 = im_open_local( lut, "im_tone_analyse:3", "p" );
IMAGE *t4 = im_open_local( lut, "im_tone_analyse:4", "p" );
IMAGE *t6 = im_open_local( lut, "im_tone_analyse:6", "p" );
if( !t1 || !t2 || !t3 || !t4 || !t6 )
return( -1 );
/* If in is IM_CODING_LABQ, unpack.
*/
if( in->Coding == IM_CODING_LABQ ) {
if( im_LabQ2LabS( in, t1 ) )
return( -1 );
}
else
t1 = in;
/* Should now be 3-band short.
*/
if( t1->Coding != IM_CODING_NONE || t1->BandFmt != IM_BANDFMT_SHORT ||
t1->Bands != 3 ) {
im_error( "im_tone_analyse", _( "input not LabS or LabQ" ) );
return( -1 );
}
/* Extract and scale L.
*/
if( im_extract_band( t1, t2, 0 ) ||
im_shiftright( t2, t3, 5 ) ||
im_clip2us( t3, t4 ) )
return( -1 );
/* Take histogram, and make it a cumulative hist.
*/
if( im_histgr( t4, t6, -1 ) )
return( -1 );
/* Search for 0.1% mark.
*/
if( im_incheck( t6 ) )
return( -1 );
p = (int *) t6->data;
for( j = 0, i = 0; i < t6->Xsize; i++ ) {
j += p[i];
if( j > sum * (0.1 / 100.0) )
break;
}
Lb = i / 10.24;
/* Search for 99.9% mark.
*/
p = (int *) t6->data;
for( j = 0, i = t6->Xsize - 1; i > 0; i-- ) {
j += p[i];
if( j > sum * (0.1 / 100.0) )
break;
}
Lw = i / 10.24;
im_diagnostics( "im_tone_analyse: set Lb = %g, Lw = %g", Lb, Lw );
return( im_tone_build( lut, Lb, Lw, Ps, Pm, Ph, S, M, H ) );
}