/* @(#) Function to extract a portion of a Vasari format picture. * @(#) Function im_extract() assumes that the imin image * @(#) is either memory mapped or in the buffer pimin->data. * @(#) * @(#) int im_extract(pimin, pimout, pbox) * @(#) IMAGE *pimin, *pimout; * @(#) IMAGE_BOX *pbox; * @(#) * @(#) All functions return 0 on success and -1 on error * @(#) * * Copyright: 1990, J. Cupitt * * Author: J. Cupitt * Written on: 12/02/1990 * Modified on: 4/6/92, J.Cupitt * - speed up! why wasn't this done before? Why am I stupid? * - layout, messages fixed * now extracts IM_CODING_LABQ to IM_CODING_LABQ file: K.Martinez 1/7/93 * 2/7/93 JC * - adapted for partial v2 * - ANSIfied * 7/7/93 JC * - behaviour for IM_CODING_LABQ fixed * - better messages * 7/10/94 JC * - new IM_NEW() * 22/2/95 JC * - new use of im_region_region() * 6/7/98 JC * - im_extract_area() and im_extract_band() added * 11/7/01 JC * - im_extract_band() now numbers from zero * 7/11/01 JC * - oh what pain, im_extract now numbers bands from zero as well * 6/9/02 JC * - zero xoff/yoff for extracted area * 14/4/04 JC * - nope, -ve the origin * 17/7/04 * - added im_extract_bands(), remove many bands from image */ /* 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 #endif /*HAVE_CONFIG_H*/ #include #include #include #ifdef WITH_DMALLOC #include #endif /*WITH_DMALLOC*/ /* Extract one or more bands ... get number of output bands from * or->im->Bands. */ static int extract_band( REGION *or, REGION *ir, IMAGE *in, IMAGE_BOX *box ) { Rect iarea; Rect *r = &or->valid; int le = r->left; int ri = IM_RECT_RIGHT(r); int to = r->top; int bo = IM_RECT_BOTTOM(r); int es = IM_IMAGE_SIZEOF_ELEMENT( ir->im ); int ipel = IM_IMAGE_SIZEOF_PEL( ir->im ); int opel = IM_IMAGE_SIZEOF_PEL( or->im ); char *p, *q; int x, y, z; /* Ask for input we need. */ iarea = or->valid; iarea.left += box->xstart; iarea.top += box->ystart; if( im_prepare( ir, &iarea ) ) return( -1 ); for( y = to; y < bo; y++ ) { p = IM_REGION_ADDR( ir, le + box->xstart, y + box->ystart ) + box->chsel * es; q = IM_REGION_ADDR( or, le, y ); for( x = le; x < ri; x++ ) { for( z = 0; z < opel; z++ ) q[z] = p[z]; p += ipel; q += opel; } } return( 0 ); } /* Extract an area. Can just use pointers. */ static int extract_area( REGION *or, REGION *ir, IMAGE *in, IMAGE_BOX *box ) { Rect iarea; /* Ask for input we need. Translate from demand in or's space to * demand in ir's space. */ iarea = or->valid; iarea.left += box->xstart; iarea.top += box->ystart; if( im_prepare( ir, &iarea ) ) return( -1 ); /* Attach or to ir. */ if( im_region_region( or, ir, &or->valid, iarea.left, iarea.top ) ) return( -1 ); return( 0 ); } /* Extract an area and bands from an image. */ int im_extract_areabands( IMAGE *in, IMAGE *out, int left, int top, int width, int height, int band, int nbands ) { IMAGE_BOX *box; if( im_piocheck( in, out ) ) return( -1 ); if( band < 0 || nbands < 1 || band + nbands > in->Bands ) { im_error( "im_extract_areabands", _( "band selection out of range" ) ); return( -1 ); } if( left + width > in->Xsize || top + height > in->Ysize || left < 0 || top < 0 || width <= 0 || height <= 0 ) { im_error( "im_extract_areabands", _( "bad extract area" ) ); return( -1 ); } if( in->Coding != IM_CODING_NONE ) { if( in->Coding != IM_CODING_LABQ ) { im_error( "im_extract_areabands", _( "unknown coding" ) ); return( -1 ); } /* We only do area extract for coding == labq. */ if( band != 0 || nbands != in->Bands ) { im_error( "im_extract_areabands", _( "can only extract areas from LABQ" ) ); return( -1 ); } } /* Set up the output header. */ if( im_cp_desc( out, in ) ) return( -1 ); out->Bands = nbands; out->Xsize = width; out->Ysize = height; if( im_demand_hint( out, IM_THINSTRIP, in, NULL ) ) return( -1 ); if( !(box = IM_NEW( out, IMAGE_BOX )) ) return( -1 ); box->xstart = left; box->ystart = top; box->xsize = width; box->ysize = height; box->chsel = band; /* Extracting all bands is a special case ... we can do it with * pointers. */ if( band == 0 && nbands == in->Bands ) { if( im_generate( out, im_start_one, extract_area, im_stop_one, in, box ) ) return( -1 ); } else { if( im_generate( out, im_start_one, extract_band, im_stop_one, in, box ) ) return( -1 ); } out->Xoffset = -left; out->Yoffset = -top; return( 0 ); } /* Legacy interface. */ int im_extract( IMAGE *in, IMAGE *out, IMAGE_BOX *box ) { if( box->chsel == -1 ) return( im_extract_areabands( in, out, box->xstart, box->ystart, box->xsize, box->ysize, 0, in->Bands ) ); else return( im_extract_areabands( in, out, box->xstart, box->ystart, box->xsize, box->ysize, box->chsel, 1 ) ); } /* Convenience functions. */ int im_extract_area( IMAGE *in, IMAGE *out, int left, int top, int width, int height ) { return( im_extract_areabands( in, out, left, top, width, height, 0, in->Bands ) ); } int im_extract_bands( IMAGE *in, IMAGE *out, int chsel, int nbands ) { return( im_extract_areabands( in, out, 0, 0, in->Xsize, in->Ysize, chsel, nbands ) ); } int im_extract_band( IMAGE *in, IMAGE *out, int chsel ) { return( im_extract_bands( in, out, chsel, 1 ) ); }