| /* Affine transforms. |
| */ |
| |
| /* |
| |
| Copyright (C) 1991-2003 The National Gallery |
| |
| This program 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 |
| |
| */ |
| |
| /* Params for an affine transformation. |
| */ |
| typedef struct { |
| /* Area of input we can use. This can be smaller than the real input |
| * image: we expand the input to add extra pixels for interpolation. |
| */ |
| Rect iarea; |
| |
| /* The area of the output we've been asked to generate. left/top can |
| * be negative. |
| */ |
| Rect oarea; |
| |
| /* The transform. |
| */ |
| double a, b, c, d; |
| double dx, dy; |
| |
| double ia, ib, ic, id; /* Inverse of matrix abcd */ |
| } Transformation; |
| |
| void im__transform_init( Transformation *trn ); |
| int im__transform_calc_inverse( Transformation *trn ); |
| int im__transform_isidentity( const Transformation *trn ); |
| int im__transform_add( const Transformation *in1, const Transformation *in2, |
| Transformation *out ); |
| void im__transform_print( const Transformation *trn ); |
| |
| void im__transform_forward_point( const Transformation *trn, |
| const double x, const double y, double *ox, double *oy ); |
| void im__transform_invert_point( const Transformation *trn, |
| const double x, const double y, double *ox, double *oy ); |
| void im__transform_forward_rect( const Transformation *trn, |
| const Rect *in, Rect *out ); |
| void im__transform_invert_rect( const Transformation *trn, |
| const Rect *in, Rect *out ); |
| |
| void im__transform_set_area( Transformation * ); |
| |
| int im__affine( IMAGE *in, IMAGE *out, Transformation *trn ); |