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vips_quadratic() uses an interpolator

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This commit is contained in:
John Cupitt 2012-11-09 14:53:32 +00:00
parent 8f364a8b51
commit b6a1c87d9c
2 changed files with 72 additions and 111 deletions
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9
TODO
View File

@ -3,13 +3,14 @@
start to get jaggies on lines --- the 3rd differential isn't being
initialised correctly for the sub-region?
seems fine vertically, only get horizontal in tile boundaries
seems fine vertically, only get errors on horizontal tile boundaries
because we step across tiles left to right: y doesn't change, only x does
- seems to leak with vips_check_matrix()?
- use interpolate arg if set
- test with interpolators
- perhaps keep inline bilinear as an option? benchmark
@ -24,8 +25,6 @@
need to add an "invalidate" signal to operation
- move resample part of transform plugin into libvips
- check CMC equations against web
http://en.wikipedia.org/wiki/Color_difference#CMC_l:c_.281984.29

174
libvips/resample/quadratic.c
View File

@ -89,91 +89,50 @@ typedef VipsResampleClass VipsQuadraticClass;
G_DEFINE_TYPE( VipsQuadratic, vips_quadratic, VIPS_TYPE_RESAMPLE );
/* Inner bilinear interpolation loop. Integer types.
*/
#define IPOL_INNERI( TYPE ) { \
TYPE *from = (TYPE *) p; \
TYPE *to = (TYPE *) q; \
int i; \
\
for( i = 0; i < bands; i++ ) { \
double value = \
f1 * from[t2 + t4 + i] + \
f2 * from[t2 + t5 + i] + \
f3 * from[t3 + t4 + i] + \
f4 * from[t3 + t5 + i]; \
to[i] = (int) (value + 0.5); \
} \
}
/* Inner bilinear interpolation loop. Float types.
*/
#define IPOL_INNERF( TYPE ) { \
TYPE *from = (TYPE *) p; \
TYPE *to = (TYPE *) q; \
int i; \
\
for( i = 0; i < bands; i++ ) { \
double value = \
f1 * from[t2 + t4 + i] + \
f2 * from[t2 + t5 + i] + \
f3 * from[t3 + t4 + i] + \
f4 * from[t3 + t5 + i]; \
to[i] = value; \
} \
}
#define TYPE_SWITCH_IPOL \
switch( bandfmt ) { \
case IM_BANDFMT_UCHAR: IPOL_INNERI( unsigned char ); break; \
case IM_BANDFMT_USHORT: IPOL_INNERI( unsigned short ); break; \
case IM_BANDFMT_UINT: IPOL_INNERI( unsigned int ); break; \
case IM_BANDFMT_CHAR: IPOL_INNERI( signed char ); break; \
case IM_BANDFMT_SHORT: IPOL_INNERI( signed short ); break; \
case IM_BANDFMT_INT: IPOL_INNERI( signed int ); break; \
case IM_BANDFMT_FLOAT: IPOL_INNERF( float ); break; \
case IM_BANDFMT_DOUBLE: IPOL_INNERF( double ); break; \
\
default: \
g_assert( 0 ); \
/*NOTREACHED*/ \
}
static int
vips_quadratic_gen( VipsRegion *or, void *vseq,
void *a, void *b, gboolean *stop )
{
const VipsImage *in = (VipsImage *) a;
VipsRegion *ir = (VipsRegion *) vseq;
VipsQuadratic *quadratic = (VipsQuadratic *) b;
VipsResample *resample = VIPS_RESAMPLE( quadratic );
VipsInterpolateMethod interpolate_fn =
vips_interpolate_get_method( quadratic->interpolate );
/* @in is the enlarged image (borders on, after vips_embed()). Use
* @resample->in for the original, not-expanded image.
*/
const VipsImage *in = (VipsImage *) a;
const int ps = VIPS_IMAGE_SIZEOF_PEL( in );
double *vec = (double *) VIPS_IMAGE_ADDR( quadratic->mat, 0, 0 );
int sizex = in->Xsize;
int sizey = in->Ysize;
int bands = in->Bands;
int bandfmt = in->BandFmt;
const int sizex1 = sizex - 1;
const int sizey1 = sizey - 1;
int clip_width = resample->in->Xsize;
int clip_height = resample->in->Ysize;
int xlow = or->valid.left;
int ylow = or->valid.top;
int xhigh = IM_RECT_RIGHT( &or->valid );
int yhigh = IM_RECT_BOTTOM( &or->valid );
int xhigh = VIPS_RECT_RIGHT( &or->valid );
int yhigh = VIPS_RECT_BOTTOM( &or->valid );
PEL *p = VIPS_IMAGE_ADDR( in, 0, 0 );
PEL *q;
VipsPel *q;
int xi1, yi1; /* 1 + input coordinates */
int xo, yo; /* output coordinates, dstimage */
int z;
double fxi, fyi; /* input coordinates */
double frx, fry; /* fractinal part of input coord. */
double frx1, fry1; /* 1.0 - fract. part of input coord. */
double dx, dy; /* xo derivative of input coord. */
double ddx, ddy; /* 2nd xo derivative of input coord. */
VipsRect image;
image.left = 0;
image.top = 0;
image.width = in->Xsize;
image.height = in->Ysize;
if( vips_region_image( ir, &image ) )
return( -1 );
for( yo = ylow; yo < yhigh; yo++ ) {
fxi = xlow + vec[0]; /* order 0 */
fyi = yo + vec[1];
@ -211,11 +170,9 @@ vips_quadratic_gen( VipsRegion *or, void *vseq,
return(-7);
}
q = (PEL *) IM_REGION_ADDR( or, xlow, yo );
q = VIPS_REGION_ADDR( or, xlow, yo );
for( xo = xlow; xo < xhigh; xo++ ) {
int t1, t2, t3, t4, t5;
double f1, f2, f3, f4;
int xi, yi;
xi = fxi;
@ -223,34 +180,16 @@ vips_quadratic_gen( VipsRegion *or, void *vseq,
/* Clipping!
*/
if( xi < 0 || xi >= sizex1 || yi < 0 || yi >= sizey1 ) {
if( xi < 0 ||
yi < 0 ||
xi >= clip_width ||
yi >= clip_height ) {
for( z = 0; z < ps; z++ )
q[z] = 0;
}
else {
/*
interpolate( affine->interpolate,
else
interpolate_fn( quadratic->interpolate,
q, ir, fxi, fyi );
*/
frx = fxi - xi;
frx1 = 1.0 - frx;
fry = fyi - yi;
fry1 = 1.0 - fry;
xi1 = xi + 1;
yi1 = yi + 1;
t1 = sizex * bands;
t2 = yi * t1;
t3 = yi1 * t1;
t4 = xi * bands;
t5 = xi1 * bands;
f1 = frx1 * fry1;
f2 = frx * fry1;
f3 = frx1 * fry;
f4 = frx * fry;
TYPE_SWITCH_IPOL;
}
q += ps;
@ -274,22 +213,19 @@ vips_quadratic_build( VipsObject *object )
VipsResample *resample = VIPS_RESAMPLE( object );
VipsQuadratic *quadratic = (VipsQuadratic *) object;
/* Default to "bilinear".
*/
if( !vips_object_argument_isset( object, "interpolate" ) )
g_object_set( object,
"interpolate", vips_interpolate_new( "bilinear" ),
NULL );
VipsInterpolate *interpolate;
int window_size;
int window_offset;
VipsImage *in;
VipsImage *t;
if( VIPS_OBJECT_CLASS( vips_quadratic_parent_class )->build( object ) )
return( -1 );
/* We need random access to our input.
*/
if( vips_image_wio_input( resample->in ) )
return( -1 );
if( vips_check_uncoded( class->nickname, resample->in ) ||
vips_check_noncomplex( class->nickname, resample->in ) ||
in = resample->in;
if( vips_check_uncoded( class->nickname, in ) ||
vips_check_noncomplex( class->nickname, in ) ||
vips_check_matrix( class->nickname,
quadratic->coeff, &quadratic->mat ) )
return( -1 );
@ -323,6 +259,32 @@ vips_quadratic_build( VipsObject *object )
return( -1 );
}
if( !vips_object_argument_isset( object, "interpolator" ) )
g_object_set( object,
"interpolator", vips_interpolate_new( "bilinear" ),
NULL );
interpolate = quadratic->interpolate;
window_size = vips_interpolate_get_window_size( interpolate );
window_offset = vips_interpolate_get_window_offset( interpolate );
/* Enlarge the input image.
*/
if( vips_embed( in, &t,
window_offset, window_offset,
in->Xsize + window_size, in->Ysize + window_size,
"extend", VIPS_EXTEND_COPY,
NULL ) )
return( -1 );
vips_object_local( object, t );
in = t;
/* We need random access to our input.
*/
if( vips_image_wio_input( in ) )
return( -1 );
/* We have the whole of the input in memory, so we can generate any
* output.
*/
@ -330,8 +292,8 @@ vips_quadratic_build( VipsObject *object )
VIPS_DEMAND_STYLE_ANY, resample->in, NULL );
if( vips_image_generate( resample->out,
NULL, vips_quadratic_gen, NULL,
resample->in, quadratic ) )
vips_start_one, vips_quadratic_gen, vips_stop_one,
in, quadratic ) )
return( -1 );
return( 0 );