/* @(#) Zoom an image by pixel replication. Any non-coded type, also works for * @(#) IM_CODING_LABQ. * @(#) * @(#) int im_zoom( in, out, factor ) * @(#) IMAGE *in, *out; * @(#) int factor; * @(#) * @(#) Returns: -1 on error, else 0 * Author: N. Martinez 1991 * 6/6/94 JC * - rewritten to ANSI-C * - now works for any type, including IM_CODING_LABQ * 7/10/94 JC * - new IM_ARRAY() macro * 26/1/96 JC * - separate x and y zoom factors * 21/8/96 JC * - partial, yuk! this is so complicated ... * 30/8/96 JC * - sets demand_hint * 10/2/00 JC * - check for integer overflow in zoom facs ... was happening with ip's * zoom on large images * 3/8/02 JC * - fall back to im_copy() for x & y factors == 1 */ /* 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 */ /* * TODO: * Test for pixel size and use memcpy() on individual pixels once they reach * sizes of the order of tens of bytes. char-wise copy is quiker than * memcpy() for smaller pixels. * * Also, I haven't tested it but int-wise copying may be faster still, as * long as alignment permits it. * * tcv. 2006-09-01 */ /* Turn off assert(). #define NDEBUG 1 */ /* Turn on IM_REGION_ADDR() range checks. #define DEBUG 1 */ #ifdef HAVE_CONFIG_H #include #endif /*HAVE_CONFIG_H*/ #include #include #include #include #include #include #include #ifdef WITH_DMALLOC #include #endif /*WITH_DMALLOC*/ /* Round N down to P boundary. */ #define ROUND_DOWN(N,P) ((N) - ((N) % P)) /* Round N up to P boundary. */ #define ROUND_UP(N,P) (ROUND_DOWN( (N) + (P) - 1, (P) )) /* Our main parameter struct. */ typedef struct { int xfac; /* Scale factors */ int yfac; } ZoomInfo; /* Paint the part of the region containing only whole pels. */ static void paint_whole( REGION *or, REGION *ir, ZoomInfo *zm, const int left, const int right, const int top, const int bottom ) { const int ps = IM_IMAGE_SIZEOF_PEL( ir->im ); const int ls = IM_REGION_LSKIP( or ); const int rs = ps * (right - left); /* Transform to ir coordinates. */ const int ileft = left / zm->xfac; const int iright = right / zm->xfac; const int itop = top / zm->yfac; const int ibottom = bottom / zm->yfac; int x, y, z, i; /* We know this! */ assert( right > left && bottom > top && right % zm->xfac == 0 && left % zm->xfac == 0 && top % zm->yfac == 0 && bottom % zm->yfac == 0 ); /* Loop over input, as we know we are all whole. */ for( y = itop; y < ibottom; y++ ) { PEL *p = (PEL *) IM_REGION_ADDR( ir, ileft, y ); PEL *q = (PEL *) IM_REGION_ADDR( or, left, y * zm->yfac ); PEL *r; /* Expand the first line of pels. */ r = q; for( x = ileft; x < iright; x++ ) { /* Copy each pel xfac times. */ for( z = 0; z < zm->xfac; z++ ) { for( i = 0; i < ps; i++ ) r[i] = p[i]; r += ps; } p += ps; } /* Copy the expanded line yfac-1 times. */ r = q + ls; for( z = 1; z < zm->yfac; z++ ) { memcpy( r, q, rs ); r += ls; } } } /* Paint the part of the region containing only part-pels. */ static void paint_part( REGION *or, REGION *ir, const ZoomInfo *zm, const int left, const int right, const int top, const int bottom ) { const int ps = IM_IMAGE_SIZEOF_PEL( ir->im ); const int ls = IM_REGION_LSKIP( or ); const int rs = ps * (right - left); /* Start position in input. */ const int ix = left / zm->xfac; const int iy = top / zm->yfac; /* Pels down to yfac boundary, pels down to bottom. Do the smallest of * these for first y loop. */ const int ptbound = (iy + 1) * zm->yfac - top; const int ptbot = bottom - top; int yt = IM_MIN( ptbound, ptbot ); int x, y, z, i; /* Only know this. */ assert( right - left >= 0 && bottom - top >= 0 ); /* Have to loop over output. */ for( y = top; y < bottom; ) { PEL *p = (PEL *) IM_REGION_ADDR( ir, ix, y / zm->yfac ); PEL *q = (PEL *) IM_REGION_ADDR( or, left, y ); PEL *r; /* Output pels until we jump the input pointer. */ int xt = (ix + 1) * zm->xfac - left; /* Loop for this output line. */ r = q; for( x = left; x < right; x++ ) { /* Copy 1 pel. */ for( i = 0; i < ps; i++ ) r[i] = p[i]; r += ps; /* Move input if on boundary. */ --xt; if( xt == 0 ) { xt = zm->xfac; p += ps; } } /* Repeat that output line until the bottom of this pixel * boundary, or we hit bottom. */ r = q + ls; for( z = 1; z < yt; z++ ) { memcpy( r, q, rs ); r += ls; } /* Move y on by the number of lines we wrote. */ y += yt; /* Reset yt for next iteration. */ yt = zm->yfac; } } /* Zoom a REGION. */ static int zoom_gen( REGION *or, void *seq, void *a, void *b ) { REGION *ir = (REGION *) seq; ZoomInfo *zm = (ZoomInfo *) b; /* Output area we are building. */ const Rect *r = &or->valid; const int ri = IM_RECT_RIGHT( r ); const int bo = IM_RECT_BOTTOM(r); Rect s; int left, right, top, bottom; int width, height; /* Area of input we need. We have to round out, as we may have * part-pixels all around the edges. */ left = ROUND_DOWN( r->left, zm->xfac ); right = ROUND_UP( ri, zm->xfac ); top = ROUND_DOWN( r->top, zm->yfac ); bottom = ROUND_UP( bo, zm->yfac ); width = right - left; height = bottom - top; s.left = left / zm->xfac; s.top = top / zm->yfac; s.width = width / zm->xfac; s.height = height / zm->yfac; if( im_prepare( ir, &s ) ) return( -1 ); /* Find the part of the output (if any) which uses only whole pels. */ left = ROUND_UP( r->left, zm->xfac ); right = ROUND_DOWN( ri, zm->xfac ); top = ROUND_UP( r->top, zm->yfac ); bottom = ROUND_DOWN( bo, zm->yfac ); width = right - left; height = bottom - top; /* Stage 1: we just paint the whole pels in the centre of the region. * As we know they are not clipped, we can do it quickly. */ if( width > 0 && height > 0 ) paint_whole( or, ir, zm, left, right, top, bottom ); /* Just fractional pixels left. Paint in the top, left, right and * bottom parts. */ if( top - r->top > 0 ) /* Some top pixels. */ paint_part( or, ir, zm, r->left, ri, r->top, IM_MIN( top, bo ) ); if( left - r->left > 0 && height > 0 ) /* Left pixels. */ paint_part( or, ir, zm, r->left, IM_MIN( left, ri ), top, bottom ); if( ri - right > 0 && height > 0 ) /* Right pixels. */ paint_part( or, ir, zm, IM_MAX( right, r->left ), ri, top, bottom ); if( bo - bottom > 0 && height >= 0 ) /* Bottom pixels. */ paint_part( or, ir, zm, r->left, ri, IM_MAX( bottom, r->top ), bo ); return( 0 ); } int im_zoom( IMAGE *in, IMAGE *out, int xfac, int yfac ) { ZoomInfo *zm; /* Check arguments. */ if( in->Coding != IM_CODING_NONE && in->Coding != IM_CODING_LABQ ) { im_error( "im_zoom", _( "unknown coding type" ) ); return( -1 ); } if( xfac <= 0 || yfac <= 0 ) { im_error( "im_zoom", _( "zoom factors should be >= 0" ) ); return( -1 ); } if( (double) in->Xsize * xfac > (double) INT_MAX / 2 || (double) in->Ysize * yfac > (double) INT_MAX / 2 ) { /* Make sure we won't get integer overflow. */ im_error( "im_zoom", _( "zoom factors too large" ) ); return( -1 ); } if( xfac == 1 && yfac == 1 ) return( im_copy( in, out ) ); if( im_piocheck( in, out ) ) return( -1 ); /* Make output. */ if( im_cp_desc( out, in ) ) return( -1 ); out->Xsize = in->Xsize * xfac; out->Ysize = in->Ysize * yfac; /* Save parameters. */ if( !(zm = IM_NEW( out, ZoomInfo )) ) return( -1 ); zm->xfac = xfac; zm->yfac = yfac; /* Set demand hints. THINSTRIP will prevent us from using * paint_whole() too much ... so go for FATSTRIP. */ if( im_demand_hint( out, IM_FATSTRIP, in, NULL ) ) return( -1 ); /* Generate! */ if( im_generate( out, im_start_one, zoom_gen, im_stop_one, in, zm ) ) return( -1 ); return( 0 ); }