libvips/libsrc/relational/im_blend.c

366 lines
8.6 KiB
C

/* @(#) Two images as input: must match in size and type. Build an output
* @(#) image blending pixels together according to a conditional image.
* @(#)
* @(#) The conditional image can have n bands or 1 band. If n bands, then we
* @(#) choose from the two source images an element at a time. If 1 band,
* @(#) then choose from the source images a pixel at a time.
* @(#)
* @(#) int
* @(#) im_blend( c, a, b, out )
* @(#) IMAGE *c, *a, *b;
* @(#) IMAGE *out;
* @(#)
* @(#) Returns either 0 (success) or -1 (fail).
*
* Modified:
* 15/4/05
* - from im_ifthenelse()
* 8/7/05
* - oops, broken for some combinations of band differences (thanks Joe)
*/
/*
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 <assert.h>
#include <vips/vips.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
#define iblend1( TYPE ) { \
TYPE *a = (TYPE *) ap; \
TYPE *b = (TYPE *) bp; \
TYPE *q = (TYPE *) qp; \
\
for( i = 0, x = 0; x < n; i++, x += bands ) { \
const int v = c[i]; \
\
for( z = x; z < x + bands; z++ ) \
q[z] = (v * a[z] + (255 - v) * b[z] + 128) / 255; \
} \
}
#define iblendn( TYPE ) { \
TYPE *a = (TYPE *) ap; \
TYPE *b = (TYPE *) bp; \
TYPE *q = (TYPE *) qp; \
\
for( x = 0; x < n; x += bands ) { \
for( z = x; z < x + bands; z++ ) { \
const int v = c[z]; \
\
q[z] = (v * a[z] + (255 - v) * b[z] + 128) / 255; \
} \
} \
}
#define fblend1( TYPE ) { \
TYPE *a = (TYPE *) ap; \
TYPE *b = (TYPE *) bp; \
TYPE *q = (TYPE *) qp; \
\
for( i = 0, x = 0; x < n; i++, x += bands ) { \
const double v = c[i] / 255.0; \
\
for( z = x; z < x + bands; z++ ) \
q[z] = v * a[z] + (1.0 - v) * b[z]; \
} \
}
#define fblendn( TYPE ) { \
TYPE *a = (TYPE *) ap; \
TYPE *b = (TYPE *) bp; \
TYPE *q = (TYPE *) qp; \
\
for( x = 0; x < n; x += bands ) { \
for( z = x; z < x + bands; z++ ) { \
const double v = c[z] / 255.0; \
\
q[z] = v * a[z] + (1.0 - v) * b[z]; \
} \
} \
}
#define cblend1( TYPE ) { \
TYPE *a = (TYPE *) ap; \
TYPE *b = (TYPE *) bp; \
TYPE *q = (TYPE *) qp; \
\
for( i = 0, x = 0; x < n; i++, x += bands ) { \
const double v = c[i] / 255.0; \
\
for( z = x; z < x + 2 * bands; z++ ) \
q[z] = v * a[z] + (1.0 - v) * b[z]; \
} \
}
#define cblendn( TYPE ) { \
TYPE *a = (TYPE *) ap; \
TYPE *b = (TYPE *) bp; \
TYPE *q = (TYPE *) qp; \
\
for( x = 0; x < n; x += bands ) { \
for( z = x; z < x + bands; z++ ) { \
const double v = c[z] / 255.0; \
\
q[2 * z] = v * a[2 * z] + (1.0 - v) * b[2 * z]; \
q[2 * z + 1] = v * a[2 * z + 1] + \
(1.0 - v) * b[2 * z + 1]; \
} \
} \
}
/* Blend with a 1-band conditional image.
*/
static void
blend1_buffer( PEL *qp, PEL *c, PEL *ap, PEL *bp, int width, IMAGE *im )
{
int i, x, z;
const int bands = im->Bands;
const int n = width * bands;
switch( im->BandFmt ) {
case IM_BANDFMT_UCHAR:
iblend1( unsigned char ); break;
case IM_BANDFMT_CHAR:
iblend1( signed char ); break;
case IM_BANDFMT_USHORT:
iblend1( unsigned short ); break;
case IM_BANDFMT_SHORT:
iblend1( signed short ); break;
case IM_BANDFMT_UINT:
iblend1( unsigned int ); break;
case IM_BANDFMT_INT:
iblend1( signed int ); break;
case IM_BANDFMT_FLOAT:
fblend1( float ); break;
case IM_BANDFMT_DOUBLE:
fblend1( double ); break;
case IM_BANDFMT_COMPLEX:
cblend1( float ); break;
case IM_BANDFMT_DPCOMPLEX:
cblend1( double ); break;
default:
assert( 0 );
}
}
/* Blend with a many band conditional image.
*/
static void
blendn_buffer( PEL *qp, PEL *c, PEL *ap, PEL *bp, int width, IMAGE *im )
{
int x, z;
const int bands = im->Bands;
const int n = width * bands;
switch( im->BandFmt ) {
case IM_BANDFMT_UCHAR:
iblendn( unsigned char ); break;
case IM_BANDFMT_CHAR:
iblendn( signed char ); break;
case IM_BANDFMT_USHORT:
iblendn( unsigned short ); break;
case IM_BANDFMT_SHORT:
iblendn( signed short ); break;
case IM_BANDFMT_UINT:
iblendn( unsigned int ); break;
case IM_BANDFMT_INT:
iblendn( signed int ); break;
case IM_BANDFMT_FLOAT:
fblendn( float ); break;
case IM_BANDFMT_DOUBLE:
fblendn( double ); break;
case IM_BANDFMT_COMPLEX:
cblendn( float ); break;
case IM_BANDFMT_DPCOMPLEX:
cblendn( double ); break;
default:
assert( 0 );
}
}
static int
blend_gen( REGION *or, void *seq, void *a, void *b )
{
REGION **ir = (REGION **) seq;
Rect *r = &or->valid;
int le = r->left;
int to = r->top;
int bo = IM_RECT_BOTTOM(r);
IMAGE *c = ir[0]->im;
IMAGE *a = ir[1]->im;
int c_elements = r->width * c->Bands;
int x, y;
int all0, all255;
/* Ask for condition pixels.
*/
if( im_prepare( ir[0], r ) )
return( -1 );
/* Is the conditional all zero or all non-zero? We can avoid asking
* for one of the inputs to be calculated.
*/
all0 = *((PEL *) IM_REGION_ADDR( ir[0], le, to )) == 0;
all255 = *((PEL *) IM_REGION_ADDR( ir[0], le, to )) == 255;
for( y = to; y < bo; y++ ) {
PEL *p = (PEL *) IM_REGION_ADDR( ir[0], le, y );
for( x = 0; x < c_elements; x++ ) {
all0 &= p[x] == 0;
all255 &= p[x] == 255;
}
if( !all0 && !all255 )
break;
}
if( all255 ) {
/* All 255. Point or at the then image.
*/
if( im_prepare( ir[1], r ) ||
im_region_region( or, ir[1], r, r->left, r->top ) )
return( -1 );
}
else if( all0 ) {
/* All zero. Point or at the else image.
*/
if( im_prepare( ir[2], r ) ||
im_region_region( or, ir[2], r, r->left, r->top ) )
return( -1 );
}
else {
/* Mix of set and clear ... ask for both then and else parts and
* interleave.
*/
if( im_prepare( ir[1], r ) || im_prepare( ir[2], r ) )
return( -1 );
for( y = to; y < bo; y++ ) {
PEL *cp = (PEL *) IM_REGION_ADDR( ir[0], le, y );
PEL *ap = (PEL *) IM_REGION_ADDR( ir[1], le, y );
PEL *bp = (PEL *) IM_REGION_ADDR( ir[2], le, y );
PEL *q = (PEL *) IM_REGION_ADDR( or, le, y );
if( c->Bands == 1 )
blend1_buffer( q, cp, ap, bp, r->width, a );
else
blendn_buffer( q, cp, ap, bp, r->width, a );
}
}
return( 0 );
}
int
im_blend( IMAGE *c, IMAGE *a, IMAGE *b, IMAGE *out )
{
IMAGE **in;
/* If a and b are both LABPACK, repack agan after the blend.
*/
if( a->Coding == IM_CODING_LABQ || b->Coding == IM_CODING_LABQ ) {
IMAGE *t[3];
int repack = a->Coding == IM_CODING_LABQ &&
b->Coding == IM_CODING_LABQ;
if( im_open_local_array( out, t, 3, "relational-1", "p" ) )
return( -1 );
if( a->Coding == IM_CODING_LABQ ) {
if( im_LabQ2Lab( a, t[0] ) )
return( -1 );
a = t[0];
}
if( b->Coding == IM_CODING_LABQ ) {
if( im_LabQ2Lab( b, t[1] ) )
return( -1 );
b = t[1];
}
if( repack )
return( im_blend( c, a, b, t[2] ) ||
im_Lab2LabQ( t[2], out ) );
else
return( im_blend( c, a, b, out ) );
}
/* Check args.
*/
if( a->Coding != IM_CODING_NONE || b->Coding != IM_CODING_NONE ||
c->Coding != IM_CODING_NONE ) {
im_error( "im_blend", _( "images not uncoded" ) );
return( -1 );
}
if( a->BandFmt != b->BandFmt ||
a->Bands != b->Bands ) {
im_error( "im_blend",
_( "size and format of then and else must match" ) );
return( -1 );
}
if( c->BandFmt != IM_BANDFMT_UCHAR ) {
im_error( "im_blend",
_( "conditional image must be uchar" ) );
return( -1 );
}
if( c->Bands != 1 && c->Bands != a->Bands ) {
im_error( "im_blend",
_( "conditional image must be one band or same as "
"then and else images" ) );
return( -1 );
}
if( im_piocheck( c, out ) || im_pincheck( a ) || im_pincheck( b ) )
return( -1 );
if( im_demand_hint( out, IM_THINSTRIP, a, b, c, NULL ) )
return( -1 );
/* Make output image.
*/
if( im_cp_descv( out, a, b, c, NULL ) ||
!(in = im_allocate_input_array( out, c, a, b, NULL )) ||
im_generate( out,
im_start_many, blend_gen, im_stop_many,
in, NULL ) )
return( -1 );
return( 0 );
}