libvips/libsrc/arithmetic/im_log10tra.c

168 lines
4.0 KiB
C

/* @(#) Find base 10 log of any non-complex image. Output
* @(#) is always float for integer input and double for double input.
* @(#)
* @(#) int
* @(#) im_log10tra( in, out )
* @(#) IMAGE *in, *out;
* @(#)
* @(#) Returns 0 on success and -1 on error
* @(#)
*
* Copyright: 1990, N. Dessipris, based on im_powtra()
* Author: Nicos Dessipris
* Written on: 02/05/1990
* Modified on:
* 5/5/93 JC
* - adapted from im_lintra to work with partial images
* - incorrect implementation of complex logs removed
* 1/7/93 JC
* - adapted for partial v2
* - ANSIfied
*/
/*
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 <assert.h>
#include <vips/vips.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
/* Define what we do for each band element type. Non-complex input, any
* output.
*/
#define loop(IN, OUT)\
for( y = to; y < bo; y++ ) {\
IN *p = (IN *) IM_REGION_ADDR( ir, le, y );\
OUT *q = (OUT *) IM_REGION_ADDR( or, le, y );\
\
for( x = 0; x < sz; x++ )\
*q++ = log10( *p++ );\
}
/* log10tra a small area.
*/
static int
log10tra_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);
int sz = IM_REGION_N_ELEMENTS( or );
int x, y;
/* Ask for input we need.
*/
if( im_prepare( ir, r ) )
return( -1 );
/* log10tra all input types.
*/
switch( ir->im->BandFmt ) {
case IM_BANDFMT_UCHAR: loop(unsigned char, float); break;
case IM_BANDFMT_CHAR: loop(signed char, float); break;
case IM_BANDFMT_USHORT: loop(unsigned short, float); break;
case IM_BANDFMT_SHORT: loop(signed short, float); break;
case IM_BANDFMT_UINT: loop(unsigned int, float); break;
case IM_BANDFMT_INT: loop(signed int, float); break;
case IM_BANDFMT_FLOAT: loop(float, float); break;
case IM_BANDFMT_DOUBLE: loop(double, double); break;
default:
assert( 0 );
}
return( 0 );
}
/* Log 10 transform.
*/
int
im_log10tra( IMAGE *in, IMAGE *out )
{
/* Check args.
*/
if( im_piocheck( in, out ) )
return( -1 );
if( in->Coding != IM_CODING_NONE ) {
im_error( "im_log10tra", "%s", _( "not uncoded" ) );
return( -1 );
}
if( im_iscomplex( in ) ) {
im_error( "im_log10tra", "%s", _( "not non-complex" ) );
return( -1 );
}
/* Prepare output header.
*/
if( im_cp_desc( out, in ) )
return( -1 );
switch( in->BandFmt ) {
case IM_BANDFMT_UCHAR:
case IM_BANDFMT_CHAR:
case IM_BANDFMT_USHORT:
case IM_BANDFMT_SHORT:
case IM_BANDFMT_UINT:
case IM_BANDFMT_INT:
out->Bbits = IM_BBITS_FLOAT;
out->BandFmt = IM_BANDFMT_FLOAT;
break;
case IM_BANDFMT_FLOAT:
case IM_BANDFMT_DOUBLE:
break;
default:
assert( 0 );
}
/* Set demand hints.
*/
if( im_demand_hint( out, IM_THINSTRIP, in, NULL ) )
return( -1 );
/* Generate!
*/
if( im_generate( out,
im_start_one, log10tra_gen, im_stop_one, in, NULL ) )
return( -1 );
return( 0 );
}