| /* im_vips2mask |
| * |
| * Author: J.Cupitt |
| * Written on: 6/6/94 |
| * Modified on: |
| * |
| * 16/10/06 |
| * - allow 1xn-band images too |
| * 23/2/07 |
| * - oop, broken for nx1 m-band images |
| * - now casts to double for you |
| * 1/2/10 |
| * - gtkdoc |
| */ |
| |
| /* |
| |
| 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 <string.h> |
| |
| #include <vips/vips.h> |
| |
| #ifdef WITH_DMALLOC |
| #include <dmalloc.h> |
| #endif /*WITH_DMALLOC*/ |
| |
| /** |
| * im_vips2mask: |
| * @in: input image |
| * @outname: name for output mask |
| * |
| * Make a mask from an image. All images are cast to %IM_BANDFMT_DOUBLE |
| * before processing. There are two cases for handling bands: |
| * |
| * If the image has a single band, im_vips2mask() will write a mask the same |
| * size as the image. |
| * |
| * If the image has more than one band, it must be one pixel high or wide. In |
| * this case the output mask uses that axis to represent band values. |
| * |
| * See also: im_mask2vips(), im_measure_area(). |
| * |
| * Returns: a #DOUBLEMASK with @outname set as the name, or NULL on error |
| */ |
| DOUBLEMASK * |
| im_vips2mask( IMAGE *in, const char *outname ) |
| { |
| int width, height; |
| DOUBLEMASK *out; |
| |
| /* double* only: cast if necessary. |
| */ |
| if( in->BandFmt != IM_BANDFMT_DOUBLE ) { |
| IMAGE *t; |
| |
| if( !(t = im_open( "im_vips2mask", "p" )) ) |
| return( NULL ); |
| if( im_clip2fmt( in, t, IM_BANDFMT_DOUBLE ) || |
| !(out = im_vips2mask( t, outname )) ) { |
| im_close( t ); |
| return( NULL ); |
| } |
| im_close( t ); |
| |
| return( out ); |
| } |
| |
| /* Check the image. |
| */ |
| if( im_incheck( in ) || |
| im_check_uncoded( "im_vips2mask", in ) ) |
| return( NULL ); |
| |
| if( in->Bands == 1 ) { |
| width = in->Xsize; |
| height = in->Ysize; |
| } |
| else if( in->Xsize == 1 ) { |
| width = in->Bands; |
| height = in->Ysize; |
| } |
| else if( in->Ysize == 1 ) { |
| width = in->Xsize; |
| height = in->Bands; |
| } |
| else { |
| im_error( "im_vips2mask", |
| "%s", _( "one band, nx1, or 1xn images only" ) ); |
| return( NULL ); |
| } |
| |
| if( !(out = im_create_dmask( outname, width, height )) ) |
| return( NULL ); |
| if( in->Bands > 1 && in->Ysize == 1 ) { |
| double *data = (double *) in->data; |
| int x, y; |
| |
| /* Need to transpose: the image is RGBRGBRGB, we need RRRGGGBBB. |
| */ |
| for( y = 0; y < height; y++ ) |
| for( x = 0; x < width; x++ ) |
| out->coeff[x + y * width] = |
| data[x * height + y]; |
| } |
| else |
| memcpy( out->coeff, in->data, |
| width * height * sizeof( double ) ); |
| |
| return( out ); |
| } |
| |