static int
vips_resize_build( VipsObject *object )
{
VipsResample *resample = VIPS_RESAMPLE( object );
VipsResize *resize = (VipsResize *) object;
VipsImage **t = (VipsImage **)
vips_object_local_array( object, 7 );
VipsImage *in;
int window_size;
int int_shrink;
int int_shrink_width;
double residual;
double sigma;
if( VIPS_OBJECT_CLASS( vips_resize_parent_class )->build( object ) )
return( -1 );
if( !vips_object_argument_isset( object, "interpolate" ) ) {
VipsInterpolate *interpolate;
char *nick;
if( vips_type_find( "VipsInterpolate", "bicubic" ) )
nick = "bicubic";
else
nick = "bilinear";
interpolate = vips_interpolate_new( nick );
g_object_set( object, "interpolate", interpolate, NULL );
VIPS_UNREF( interpolate );
}
in = resample->in;
window_size = resize->interpolate ?
vips_interpolate_get_window_size( resize->interpolate ) : 2;
/* If the factor is > 1.0, we need to zoom rather than shrink.
* Just set the int part to 1 in this case.
*/
int_shrink = resize->scale > 1.0 ? 1 : floor( 1.0 / resize->scale );
/* We want to shrink by less for interpolators with larger windows.
*/
int_shrink = VIPS_MAX( 1,
int_shrink / VIPS_MAX( 1, window_size / 2 ) );
/* Size after int shrink.
*/
int_shrink_width = in->Xsize / int_shrink;
/* Therefore residual scale factor is.
*/
residual = (in->Xsize * resize->scale) / int_shrink_width;
/* A copy for enlarge resize.
*/
if( vips_shrink( in, &t[0], int_shrink, int_shrink, NULL ) )
return( -1 );
in = t[0];
/* We want to make sure we read the image sequentially.
* However, the convolution we may be doing later will force us
* into SMALLTILE or maybe FATSTRIP mode and that will break
* sequentiality.
*
* So ... read into a cache where tiles are scanlines, and make sure
* we keep enough scanlines to be able to serve a line of tiles.
*
* We use a threaded tilecache to avoid a deadlock: suppose thread1,
* evaluating the top block of the output, is delayed, and thread2,
* evaluating the second block, gets here first (this can happen on
* a heavily-loaded system).
*
* With an unthreaded tilecache (as we had before), thread2 will get
* the cache lock and start evaling the second block of the shrink.
* When it reaches the png reader it will stall until the first block
* has been used ... but it never will, since thread1 will block on
* this cache lock.
*/
if( int_shrink > 1 ) {
int tile_width;
int tile_height;
int nlines;
vips_get_tile_size( in,
&tile_width, &tile_height, &nlines );
if( vips_tilecache( in, &t[6],
"tile_width", in->Xsize,
"tile_height", 10,
"max_tiles", 1 + (nlines * 2) / 10,
"access", VIPS_ACCESS_SEQUENTIAL,
"threaded", TRUE,
NULL ) )
return( -1 );
in = t[6];
}
/* If the final affine will be doing a large downsample, we can get
* nasty aliasing on hard edges. Blur before affine to smooth this out.
*
* Don't blur for very small shrinks, blur with radius 1 for x1.5
* shrinks, blur radius 2 for x2.5 shrinks and above, etc.
*/
sigma = ((1.0 / residual) - 0.5) / 1.5;
if( residual < 1.0 &&
sigma > 0.1 ) {
if( vips_gaussblur( in, &t[2], sigma, NULL ) )
return( -1 );
in = t[2];
}
if( vips_affine( in, &t[3], residual, 0, 0, residual,
"interpolate", resize->interpolate,
"idx", resize->idx,
"idy", resize->idy,
NULL ) )
return( -1 );
in = t[3];
/* If we are upsampling, don't sharpen.
*/
if( int_shrink > 1 ) {
t[5] = vips_image_new_matrixv( 3, 3,
-1.0, -1.0, -1.0,
-1.0, 32.0, -1.0,
-1.0, -1.0, -1.0 );
vips_image_set_double( t[5], "scale", 24 );
if( vips_conv( in, &t[4], t[5], NULL ) )
return( -1 );
in = t[4];
}
if( vips_image_write( in, resample->out ) )
return( -1 );
return( 0 );
}
static int
vips_smartcrop_attention( VipsSmartcrop *smartcrop,
VipsImage *in, int *left, int *top )
{
/* From smartcrop.js.
*/
static double skin_vector[] = {-0.78, -0.57, -0.44};
static double ones[] = {1.0, 1.0, 1.0};
VipsImage **t = (VipsImage **)
vips_object_local_array( VIPS_OBJECT( smartcrop ), 24 );
double hscale;
double vscale;
double sigma;
double max;
int x_pos;
int y_pos;
/* The size we shrink to gives the precision with which we can place
* the crop
*/
hscale = 32.0 / in->Xsize;
vscale = 32.0 / in->Ysize;
sigma = VIPS_MAX( sqrt( pow( smartcrop->width * hscale, 2 ) +
pow( smartcrop->height * vscale, 2 ) ) / 10, 1.0 );
if ( vips_resize( in, &t[17], hscale,
"vscale", vscale,
NULL ) )
return( -1 );
/* Simple edge detect.
*/
if( !(t[21] = vips_image_new_matrixv( 3, 3,
0.0, -1.0, 0.0,
-1.0, 4.0, -1.0,
0.0, -1.0, 0.0 )) )
return( -1 );
/* Convert to XYZ and just use the first three bands.
*/
if( vips_colourspace( t[17], &t[0], VIPS_INTERPRETATION_XYZ, NULL ) ||
vips_extract_band( t[0], &t[1], 0, "n", 3, NULL ) )
return( -1 );
/* Edge detect on Y.
*/
if( vips_extract_band( t[1], &t[2], 1, NULL ) ||
vips_conv( t[2], &t[3], t[21],
"precision", VIPS_PRECISION_INTEGER,
NULL ) ||
vips_linear1( t[3], &t[4], 5.0, 0.0, NULL ) ||
vips_abs( t[4], &t[14], NULL ) )
return( -1 );
/* Look for skin colours. Taken from smartcrop.js.
*/
if(
/* Normalise to magnitude of colour in XYZ.
*/
pythagoras( smartcrop, t[1], &t[5] ) ||
vips_divide( t[1], t[5], &t[6], NULL ) ||
/* Distance from skin point.
*/
vips_linear( t[6], &t[7], ones, skin_vector, 3, NULL ) ||
pythagoras( smartcrop, t[7], &t[8] ) ||
/* Rescale to 100 - 0 score.
*/
vips_linear1( t[8], &t[9], -100.0, 100.0, NULL ) ||
/* Ignore dark areas.
*/
vips_more_const1( t[2], &t[10], 5.0, NULL ) ||
!(t[11] = vips_image_new_from_image1( t[10], 0.0 )) ||
vips_ifthenelse( t[10], t[9], t[11], &t[15], NULL ) )
return( -1 );
/* Look for saturated areas.
*/
if( vips_colourspace( t[1], &t[12],
VIPS_INTERPRETATION_LAB, NULL ) ||
vips_extract_band( t[12], &t[13], 1, NULL ) ||
vips_ifthenelse( t[10], t[13], t[11], &t[16], NULL ) )
return( -1 );
/* Sum, blur and find maxpos.
*
* The amount of blur is related to the size of the crop
* area: how large an area we want to consider for the scoring
* function.
*/
if( vips_sum( &t[14], &t[18], 3, NULL ) ||
vips_gaussblur( t[18], &t[19], sigma, NULL ) ||
vips_max( t[19], &max, "x", &x_pos, "y", &y_pos, NULL ) )
return( -1 );
/* Centre the crop over the max.
*/
*left = VIPS_CLIP( 0,
x_pos / hscale - smartcrop->width / 2,
in->Xsize - smartcrop->width );
*top = VIPS_CLIP( 0,
y_pos / vscale - smartcrop->height / 2,
in->Ysize - smartcrop->height );
return( 0 );
}
