added mbicubic = symmetrized monotone cubic splines and added hopefully fast cast operators in templates.h
This commit is contained in:
Nicolas Robidoux
parent
31a8830f46
commit
b0b7dc43e3
@ -2,6 +2,7 @@
|
||||
if ENABLE_CXX
|
||||
C_SOURCES = \
|
||||
bicubic.cpp \
|
||||
mbicubic.cpp \
|
||||
yafrsmooth.cpp \
|
||||
nohalo1.cpp \
|
||||
snohalo1.cpp \
|
||||
@ -12,6 +13,7 @@ else
|
||||
C_SOURCES =
|
||||
C_DIST = \
|
||||
bicubic.cpp \
|
||||
mbicubic.cpp \
|
||||
yafrsmooth.cpp \
|
||||
nohalo1.cpp \
|
||||
snohalo1.cpp \
|
||||
|
||||
@ -497,6 +497,7 @@ void
|
||||
vips__interpolate_init( void )
|
||||
{
|
||||
extern GType vips_interpolate_bicubic_get_type( void );
|
||||
extern GType vips_interpolate_mbicubic_get_type( void );
|
||||
extern GType vips_interpolate_yafrsmooth_get_type( void );
|
||||
extern GType vips_interpolate_nohalo1_get_type( void );
|
||||
extern GType vips_interpolate_snohalo1_get_type( void );
|
||||
@ -507,6 +508,7 @@ vips__interpolate_init( void )
|
||||
|
||||
#ifdef ENABLE_CXX
|
||||
vips_interpolate_bicubic_get_type();
|
||||
vips_interpolate_mbicubic_get_type();
|
||||
vips_interpolate_yafrsmooth_get_type();
|
||||
vips_interpolate_nohalo1_get_type();
|
||||
vips_interpolate_snohalo1_get_type();
|
||||
|
||||
642
libvips/resample/mbicubic.cpp
Normal file
642
libvips/resample/mbicubic.cpp
Normal file
@ -0,0 +1,642 @@
|
||||
/* symmetrized monotone cubic splines
|
||||
*/
|
||||
|
||||
/*
|
||||
|
||||
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
|
||||
|
||||
*/
|
||||
|
||||
/*
|
||||
* 2009-2010 (c) Nicolas Robidoux, John Cupitt, Eric Daoust and Adam
|
||||
* Turcotte
|
||||
*
|
||||
* E. Daoust and A. Turcotte's symmetrized monotone cubic splines
|
||||
* programming funded in part by two Google Summer of Code 2010 awards
|
||||
* made to GIMP (Gnu Image Manipulation Program) and its library GEGL.
|
||||
*
|
||||
* Nicolas Robidoux thanks Chantal Racette, Ralf Meyer, Minglun Gong,
|
||||
* Øyvind Kolås, Geert Jordaens and Sven Neumann for useful comments
|
||||
* and code.
|
||||
*/
|
||||
|
||||
/*
|
||||
* mbicubic is the VIPS name of the symmetrized implementation in 2D
|
||||
* of monotone cubic spline interpolation method a.k.a. MP-Quadratic
|
||||
* (Monotonicity Preserving with derivative estimated by fitting a
|
||||
* parabola (quadratic polynomial)) method, which essentially is
|
||||
* Catmull-Rom with derivatives clamped with Fristsh and Carlson's
|
||||
* "rule of 3" so as to ensure monotonicity.
|
||||
*
|
||||
* 1D MP-quadratic (for curve, not surface, interpolation) is
|
||||
* described in
|
||||
*
|
||||
* Accurate Monotone Cubic Interpolation, by Hung T. Huynh, published
|
||||
* in the SIAM Journal on Numerical Analysis, Volume 30, Issue 1
|
||||
* (February 1993), pages 57-100, 1993. ISSN:0036-1429.
|
||||
*
|
||||
* and in NASA technical memorandum 103789, which can be downloaded
|
||||
* from http://
|
||||
* ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19910011517_1991011517.pdf
|
||||
*
|
||||
* In order to ensure reflexion symmetry about diagonal lines, 1D
|
||||
* MP-quadratic is performed two different ways---horizontally then
|
||||
* vertically, and vertically then horizontally---and
|
||||
* averaged. (Symmetry about 45 degree lines is not automatically
|
||||
* respected because MP-quadratic is a nonlinear method: interpolating
|
||||
* horizontally then vertically does not necessarily give the same as
|
||||
* interpolating vertically then horizontally.)
|
||||
*/
|
||||
|
||||
#ifdef HAVE_CONFIG_H
|
||||
#include <config.h>
|
||||
#endif /*HAVE_CONFIG_H*/
|
||||
#include <vips/intl.h>
|
||||
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
|
||||
#include <vips/vips.h>
|
||||
#include <vips/internal.h>
|
||||
|
||||
#include "templates.h"
|
||||
|
||||
#define VIPS_TYPE_INTERPOLATE_MBICUBIC \
|
||||
(vips_interpolate_mbicubic_get_type())
|
||||
#define VIPS_INTERPOLATE_MBICUBIC( obj ) \
|
||||
(G_TYPE_CHECK_INSTANCE_CAST( (obj), \
|
||||
VIPS_TYPE_INTERPOLATE_MBICUBIC, VipsInterpolateMbicubic ))
|
||||
#define VIPS_INTERPOLATE_MBICUBIC_CLASS( klass ) \
|
||||
(G_TYPE_CHECK_CLASS_CAST( (klass), \
|
||||
VIPS_TYPE_INTERPOLATE_MBICUBIC, VipsInterpolateMbicubicClass))
|
||||
#define VIPS_IS_INTERPOLATE_MBICUBIC( obj ) \
|
||||
(G_TYPE_CHECK_INSTANCE_TYPE( (obj), VIPS_TYPE_INTERPOLATE_MBICUBIC ))
|
||||
#define VIPS_IS_INTERPOLATE_MBICUBIC_CLASS( klass ) \
|
||||
(G_TYPE_CHECK_CLASS_TYPE( (klass), VIPS_TYPE_INTERPOLATE_MBICUBIC ))
|
||||
#define VIPS_INTERPOLATE_MBICUBIC_GET_CLASS( obj ) \
|
||||
(G_TYPE_INSTANCE_GET_CLASS( (obj), \
|
||||
VIPS_TYPE_INTERPOLATE_MBICUBIC, VipsInterpolateMbicubicClass ))
|
||||
|
||||
typedef struct _VipsInterpolateMbicubic {
|
||||
VipsInterpolate parent_object;
|
||||
|
||||
} VipsInterpolateMbicubic;
|
||||
|
||||
typedef struct _VipsInterpolateMbicubicClass {
|
||||
VipsInterpolateClass parent_class;
|
||||
|
||||
} VipsInterpolateMbicubicClass;
|
||||
|
||||
/*
|
||||
* MINMOD is an implementation of the minmod function which only needs
|
||||
* two conditional moves.
|
||||
*
|
||||
* MINMOD(a,b,a_times_a,a_times_b) "returns" minmod(a,b). The
|
||||
* parameter ("input") a_times_a is assumed to contain the square of
|
||||
* a; the parameter a_times_b, the product of a and b.
|
||||
*
|
||||
* The version most suitable for images with flat (constant) colour
|
||||
* areas, since a, which is a pixel difference, will often be 0, in
|
||||
* which case both forward branches are likely:
|
||||
*
|
||||
* ( (a_times_b)>=0 ? 1. : 0. ) * ( (a_times_a)<=(a_times_b) ? (a) : (b) )
|
||||
*
|
||||
* For uncompressed natural images in high bit depth (images for which
|
||||
* the slopes a and b are unlikely to be equal to zero or be equal to
|
||||
* each other), we recommend using
|
||||
*
|
||||
* ( (a_times_b)>=0. ? 1. : 0. ) * ( (a_times_b)<(a_times_a) ? (b) : (a) )
|
||||
*
|
||||
* instead. With this second version, the forward branch of the second
|
||||
* conditional move is taken when |b|>|a| and when a*b<0. However, the
|
||||
* "else" branch is taken when a=0 (or when a=b), which is why this
|
||||
* second version is not recommended for images with large regions
|
||||
* with constant pixel values (or even, actually, regions with nearby
|
||||
* pixel values which vary bilinearly, which may arise from dirt-cheap
|
||||
* demosaicing or computer graphics operations).
|
||||
*
|
||||
* Both of the above use a multiplication instead of a nested
|
||||
* "if-then-else" because gcc does not always rewrite the latter using
|
||||
* conditional moves.
|
||||
*
|
||||
* Implementation note: Both of the above are better than FAST_MINMOD
|
||||
* (currently found in templates.h and used by the "classic"
|
||||
* implementations of the other Nohalo methods). Unfortunately, MINMOD
|
||||
* uses different parameters and consequently is not a direct
|
||||
* substitute. To be fixed in the future.
|
||||
*
|
||||
* Note that the two variants differ in whether (a) or (b) follows the
|
||||
* forward branch. If there is a difference in likelihood, put the
|
||||
* likely one in (a) in the first variant, and the likely one in (b)
|
||||
* in the second.
|
||||
*/
|
||||
#define MINMOD(a,b,a_times_a,a_times_b) \
|
||||
( (a_times_b)>=0. ? 1. : 0. ) * ( (a_times_b)<(a_times_a) ? (b) : (a) )
|
||||
|
||||
static inline double
|
||||
mcubic( const double one,
|
||||
const double two,
|
||||
const double thr,
|
||||
const double fou,
|
||||
const double coef_thr_point,
|
||||
const double half_coef_two_slope,
|
||||
const double half_coef_thr_slope )
|
||||
{
|
||||
/*
|
||||
* Computation of the slopes and slope limiters:
|
||||
*
|
||||
* Differences:
|
||||
*/
|
||||
const double prem = two - one;
|
||||
const double deux = thr - two;
|
||||
const double troi = fou - thr;
|
||||
|
||||
const double part = two + deux * coef_thr_point;
|
||||
|
||||
/*
|
||||
* Products useful for the minmod computations:
|
||||
*/
|
||||
const double deux_prem = deux * prem;
|
||||
const double deux_deux = deux * deux;
|
||||
const double deux_troi = deux * troi;
|
||||
|
||||
/*
|
||||
* Twice the horizontal limiter slopes (twice_lx) interwoven with
|
||||
* twice the Catmull-Rom slopes (twice_sx). Because we have twice
|
||||
* the Catmull-Rom slope, we need to use 6 times the minmod slope
|
||||
* instead of the usual 3 (specified by the cited article).
|
||||
*/
|
||||
const double twice_lx_two =
|
||||
6. * MINMOD( deux, prem, deux_deux, deux_prem );
|
||||
const double twice_sx_two = deux + prem;
|
||||
const double twice_lx_thr =
|
||||
6. * MINMOD( deux, troi, deux_deux, deux_troi );
|
||||
const double twice_sx_thr = deux + troi;
|
||||
|
||||
const double lx_lx_two = twice_lx_two * twice_lx_two;
|
||||
const double lx_sx_two = twice_lx_two * twice_sx_two;
|
||||
const double lx_lx_thr = twice_lx_thr * twice_lx_thr;
|
||||
const double lx_sx_thr = twice_lx_thr * twice_sx_thr;
|
||||
|
||||
/*
|
||||
* Result of the first interpolations along horizontal lines. Note
|
||||
* that the Catmull-Rom slope almost always satisfies the
|
||||
* monotonicity constraint, hence twice_sx is "likely" to be the one
|
||||
* selected by minmod.
|
||||
*/
|
||||
const double newval =
|
||||
part +
|
||||
+ half_coef_two_slope
|
||||
* MINMOD( twice_lx_two, twice_sx_two, lx_lx_two, lx_sx_two )
|
||||
+ half_coef_thr_slope
|
||||
* MINMOD( twice_lx_thr, twice_sx_thr, lx_lx_thr, lx_sx_thr );
|
||||
|
||||
return newval;
|
||||
}
|
||||
|
||||
static inline double
|
||||
symmetrized_monotone_cubic_splines( const double coef_rite_point,
|
||||
const double coef_bot_point,
|
||||
const double half_coef_left_slope,
|
||||
const double half_coef_rite_slope,
|
||||
const double half_coef_top_slope,
|
||||
const double half_coef_bot_slope,
|
||||
const double uno_one,
|
||||
const double uno_two,
|
||||
const double uno_thr,
|
||||
const double uno_fou,
|
||||
const double dos_one,
|
||||
const double dos_two,
|
||||
const double dos_thr,
|
||||
const double dos_fou,
|
||||
const double tre_one,
|
||||
const double tre_two,
|
||||
const double tre_thr,
|
||||
const double tre_fou,
|
||||
const double qua_one,
|
||||
const double qua_two,
|
||||
const double qua_thr,
|
||||
const double qua_fou )
|
||||
{
|
||||
/*
|
||||
* STENCIL (FOOTPRINT) OF INPUT VALUES:
|
||||
*
|
||||
* The stencil of Symmetrized Monotone Catmull-Rom is the same as
|
||||
* the standard Catmull-Rom's:
|
||||
*
|
||||
* (ix-1,iy-1) (ix,iy-1) (ix+1,iy-1) (ix+2,iy-1)
|
||||
* = uno_one = uno_two = uno_thr = uno_fou
|
||||
*
|
||||
* (ix-1,iy) (ix,iy) (ix+1,iy) (ix+2,iy)
|
||||
* = dos_one = dos_two = dos_thr = dos_fou
|
||||
* X
|
||||
* (ix-1,iy+1) (ix,iy+1) (ix+1,iy+1) (ix+2,iy+1)
|
||||
* = tre_one = tre_two = tre_thr = tre_fou
|
||||
*
|
||||
* (ix-1,iy+2) (ix,iy+2) (ix+1,iy+2) (ix+2,iy+2)
|
||||
* = qua_one = qua_two = qua_thr = qua_fou
|
||||
*
|
||||
* where ix is the (pseudo-)floor of the requested left-to-right
|
||||
* location ("X"), and iy is the floor of the requested up-to-down
|
||||
* location.
|
||||
*/
|
||||
/*
|
||||
* Outline of the computation:
|
||||
*
|
||||
* First, four horizontal cubic Hermite interpolations are performed
|
||||
* to get values on the vertical line which passes through X, and
|
||||
* then these four values are used to perform cubic Hermite
|
||||
* interpolation in the vertical direction to get one approximation
|
||||
* of the pixel value at X,
|
||||
*
|
||||
* Then, four vertical cubic Hermite interpolations are performed to
|
||||
* get values on the horizontal line which passes through X, and
|
||||
* then these four values are used to perform cubic Hermite
|
||||
* interpolation in the horizontal direction to get another
|
||||
* approximation of the pixel value at X,
|
||||
*
|
||||
* These two interpolated pixel values are then averaged.
|
||||
*/
|
||||
|
||||
/*
|
||||
* Computation of the slopes and slope limiters:
|
||||
*
|
||||
* Uno horizontal differences:
|
||||
*/
|
||||
const double uno = mcubic( uno_one,
|
||||
uno_two,
|
||||
uno_thr,
|
||||
uno_fou,
|
||||
coef_rite_point,
|
||||
half_coef_left_slope,
|
||||
half_coef_rite_slope );
|
||||
/*
|
||||
* Do the same with the other three horizontal lines.
|
||||
*
|
||||
* Dos horizontal line:
|
||||
*/
|
||||
const double dos = mcubic( dos_one,
|
||||
dos_two,
|
||||
dos_thr,
|
||||
dos_fou,
|
||||
coef_rite_point,
|
||||
half_coef_left_slope,
|
||||
half_coef_rite_slope );
|
||||
/*
|
||||
* Tre(s) horizontal line:
|
||||
*/
|
||||
const double tre = mcubic( tre_one,
|
||||
tre_two,
|
||||
tre_thr,
|
||||
tre_fou,
|
||||
coef_rite_point,
|
||||
half_coef_left_slope,
|
||||
half_coef_rite_slope );
|
||||
/*
|
||||
* Qua(ttro) horizontal line:
|
||||
*/
|
||||
const double qua = mcubic( qua_one,
|
||||
qua_two,
|
||||
qua_thr,
|
||||
qua_fou,
|
||||
coef_rite_point,
|
||||
half_coef_left_slope,
|
||||
half_coef_rite_slope );
|
||||
|
||||
/*
|
||||
* Perform the interpolation along the one vertical line (filled
|
||||
* with results obtained by interpolating along horizontal lines):
|
||||
*/
|
||||
const double partial_y = mcubic( uno,
|
||||
dos,
|
||||
tre,
|
||||
qua,
|
||||
coef_bot_point,
|
||||
half_coef_top_slope,
|
||||
half_coef_bot_slope );
|
||||
|
||||
/*
|
||||
* Redo with four vertical lines (and the corresponding horizontal
|
||||
* one).
|
||||
*
|
||||
* One:
|
||||
*/
|
||||
const double one = mcubic( uno_one,
|
||||
dos_one,
|
||||
tre_one,
|
||||
qua_one,
|
||||
coef_bot_point,
|
||||
half_coef_top_slope,
|
||||
half_coef_bot_slope );
|
||||
/*
|
||||
* Two:
|
||||
*/
|
||||
const double two = mcubic( uno_two,
|
||||
dos_two,
|
||||
tre_two,
|
||||
qua_two,
|
||||
coef_bot_point,
|
||||
half_coef_top_slope,
|
||||
half_coef_bot_slope );
|
||||
/*
|
||||
* Thr(ee):
|
||||
*/
|
||||
const double thr = mcubic( uno_thr,
|
||||
dos_thr,
|
||||
tre_thr,
|
||||
qua_thr,
|
||||
coef_bot_point,
|
||||
half_coef_top_slope,
|
||||
half_coef_bot_slope );
|
||||
/*
|
||||
* Fou(r):
|
||||
*/
|
||||
const double fou = mcubic( uno_fou,
|
||||
dos_fou,
|
||||
tre_fou,
|
||||
qua_fou,
|
||||
coef_bot_point,
|
||||
half_coef_top_slope,
|
||||
half_coef_bot_slope );
|
||||
|
||||
/*
|
||||
* Final horizontal line of vertical results:
|
||||
*/
|
||||
const double prem_x = two - one;
|
||||
const double deux_x = thr - two;
|
||||
const double troi_x = fou - thr;
|
||||
|
||||
const double partial_newval = partial_y + two + coef_rite_point * deux_x;
|
||||
|
||||
const double deux_prem_x = deux_x * prem_x;
|
||||
const double deux_deux_x = deux_x * deux_x;
|
||||
const double deux_troi_x = deux_x * troi_x;
|
||||
|
||||
const double twice_l_two =
|
||||
6. * MINMOD( deux_x, prem_x, deux_deux_x, deux_prem_x );
|
||||
const double twice_s_two = deux_x + prem_x;
|
||||
const double twice_l_thr =
|
||||
6. * MINMOD( deux_x, troi_x, deux_deux_x, deux_troi_x );
|
||||
const double twice_s_thr = deux_x + troi_x;
|
||||
|
||||
const double l_l_two = twice_l_two * twice_l_two;
|
||||
const double l_s_two = twice_l_two * twice_s_two;
|
||||
const double l_l_thr = twice_l_thr * twice_l_thr;
|
||||
const double l_s_thr = twice_l_thr * twice_s_thr;
|
||||
|
||||
const double newval =
|
||||
(
|
||||
partial_newval
|
||||
+
|
||||
half_coef_left_slope
|
||||
*
|
||||
MINMOD( twice_l_two, twice_s_two, l_l_two, l_s_two )
|
||||
+
|
||||
half_coef_rite_slope
|
||||
*
|
||||
MINMOD( twice_l_thr, twice_s_thr, l_l_thr, l_l_thr )
|
||||
) * .5;
|
||||
|
||||
return newval;
|
||||
}
|
||||
|
||||
/*
|
||||
* Call Snohalo with an conversion operator as a parameter.
|
||||
*
|
||||
* It would be nice to do this with templates somehow---for one thing
|
||||
* this would allow code comments!---but we can't figure a clean way
|
||||
* to do it.
|
||||
*/
|
||||
#define MBICUBIC_CONVERSION( conversion ) \
|
||||
template <typename T> static void inline \
|
||||
mbicubic_ ## conversion( PEL* restrict pout, \
|
||||
const PEL* restrict pin, \
|
||||
const int bands, \
|
||||
const int lskip, \
|
||||
const double x, \
|
||||
const double y ) \
|
||||
{ \
|
||||
T* restrict out = (T *) pout; \
|
||||
\
|
||||
const T* restrict in = (T *) pin; \
|
||||
\
|
||||
const int uno_one_shift = -lskip - bands; \
|
||||
const int uno_two_shift = -lskip ; \
|
||||
const int uno_thr_shift = -lskip + bands; \
|
||||
const int uno_fou_shift = -lskip + 2*bands; \
|
||||
\
|
||||
const int dos_one_shift = - bands; \
|
||||
const int dos_two_shift = 0; \
|
||||
const int dos_thr_shift = bands; \
|
||||
const int dos_fou_shift = 2*bands; \
|
||||
\
|
||||
const int tre_one_shift = lskip - bands; \
|
||||
const int tre_two_shift = lskip ; \
|
||||
const int tre_thr_shift = lskip + bands; \
|
||||
const int tre_fou_shift = lskip + 2*bands; \
|
||||
\
|
||||
const int qua_one_shift = 2*lskip - bands; \
|
||||
const int qua_two_shift = 2*lskip ; \
|
||||
const int qua_thr_shift = 2*lskip + bands; \
|
||||
const int qua_fou_shift = 2*lskip + 2*bands; \
|
||||
\
|
||||
const double x_squared = x * x; \
|
||||
const double y_squared = y * y; \
|
||||
const double twice_x = x + x; \
|
||||
const double twice_y = y + y; \
|
||||
const double half_x_squared_minus_x = .5 * ( x_squared - x ); \
|
||||
const double half_y_squared_minus_y = .5 * ( y_squared - y ); \
|
||||
\
|
||||
const double coef_rite_point = x_squared * ( 3. - twice_x ); \
|
||||
const double coef_bot_point = y_squared * ( 3. - twice_y ); \
|
||||
\
|
||||
const double half_coef_rite_slope = x * half_x_squared_minus_x; \
|
||||
const double half_coef_bot_slope = y * half_y_squared_minus_y; \
|
||||
const double half_coef_left_slope = \
|
||||
half_coef_rite_slope - half_x_squared_minus_x; \
|
||||
const double half_coef_top_slope = \
|
||||
half_coef_bot_slope - half_y_squared_minus_y; \
|
||||
\
|
||||
int band = bands; \
|
||||
\
|
||||
do \
|
||||
{ \
|
||||
const double double_result = \
|
||||
symmetrized_monotone_cubic_splines( coef_rite_point, \
|
||||
coef_bot_point, \
|
||||
half_coef_left_slope, \
|
||||
half_coef_rite_slope, \
|
||||
half_coef_top_slope, \
|
||||
half_coef_bot_slope, \
|
||||
in[ uno_one_shift ], \
|
||||
in[ uno_two_shift ], \
|
||||
in[ uno_thr_shift ], \
|
||||
in[ uno_fou_shift ], \
|
||||
in[ dos_one_shift ], \
|
||||
in[ dos_two_shift ], \
|
||||
in[ dos_thr_shift ], \
|
||||
in[ dos_fou_shift ], \
|
||||
in[ tre_one_shift ], \
|
||||
in[ tre_two_shift ], \
|
||||
in[ tre_thr_shift ], \
|
||||
in[ tre_fou_shift ], \
|
||||
in[ qua_one_shift ], \
|
||||
in[ qua_two_shift ], \
|
||||
in[ qua_thr_shift ], \
|
||||
in[ qua_fou_shift ] ); \
|
||||
\
|
||||
const T result = to_ ## conversion<T>( double_result ); \
|
||||
in++; \
|
||||
*out++ = result; \
|
||||
} while (--band); \
|
||||
}
|
||||
|
||||
MBICUBIC_CONVERSION( fptypes )
|
||||
MBICUBIC_CONVERSION( withsign )
|
||||
MBICUBIC_CONVERSION( nosign )
|
||||
|
||||
#define CALL( T, conversion ) \
|
||||
mbicubic_ ## conversion<T>( out, \
|
||||
p, \
|
||||
bands, \
|
||||
lskip, \
|
||||
relative_x, \
|
||||
relative_y );
|
||||
|
||||
/*
|
||||
* We need C linkage:
|
||||
*/
|
||||
extern "C" {
|
||||
G_DEFINE_TYPE( VipsInterpolateMbicubic, vips_interpolate_mbicubic,
|
||||
VIPS_TYPE_INTERPOLATE );
|
||||
}
|
||||
|
||||
static void
|
||||
vips_interpolate_mbicubic_interpolate( VipsInterpolate* restrict interpolate,
|
||||
PEL* restrict out,
|
||||
REGION* restrict in,
|
||||
double absolute_x,
|
||||
double absolute_y )
|
||||
{
|
||||
/*
|
||||
* Floor's surrogate FAST_PSEUDO_FLOOR is used to make sure that the
|
||||
* transition through 0 is smooth. If it is known that absolute_x
|
||||
* and absolute_y will never be less than 0, plain cast---that is,
|
||||
* const int ix = absolute_x---should be used instead. Actually,
|
||||
* any function which agrees with floor for non-integer values, and
|
||||
* picks one of the two possibilities for integer values, can be
|
||||
* used. FAST_PSEUDO_FLOOR fits the bill.
|
||||
*
|
||||
* Then, x is the x-coordinate of the sampling point relative to the
|
||||
* position of the center of the convex hull of the 2x2 block of
|
||||
* closest pixels. Similarly for y. Range of values: [-.5,.5).
|
||||
*/
|
||||
const int ix = FAST_PSEUDO_FLOOR( absolute_x );
|
||||
const int iy = FAST_PSEUDO_FLOOR( absolute_y );
|
||||
|
||||
/*
|
||||
* Move the pointer to (the first band of) the top/left pixel of the
|
||||
* 2x2 group of pixel centers which contains the sampling location
|
||||
* in its convex hull:
|
||||
*/
|
||||
const PEL* restrict p = (PEL *) IM_REGION_ADDR( in, ix, iy );
|
||||
|
||||
const double relative_x = absolute_x - ix;
|
||||
const double relative_y = absolute_y - iy;
|
||||
|
||||
/*
|
||||
* VIPS versions of Nicolas's pixel addressing values.
|
||||
*/
|
||||
const int actual_bands = in->im->Bands;
|
||||
const int lskip = IM_REGION_LSKIP( in ) / IM_IMAGE_SIZEOF_ELEMENT( in->im );
|
||||
/*
|
||||
* Double the bands for complex images to account for the real and
|
||||
* imaginary parts being computed independently:
|
||||
*/
|
||||
const int bands =
|
||||
vips_bandfmt_iscomplex( in->im->BandFmt ) ? 2 * actual_bands : actual_bands;
|
||||
|
||||
switch( in->im->BandFmt ) {
|
||||
case IM_BANDFMT_UCHAR:
|
||||
CALL( unsigned char, nosign );
|
||||
break;
|
||||
|
||||
case IM_BANDFMT_CHAR:
|
||||
CALL( signed char, withsign );
|
||||
break;
|
||||
|
||||
case IM_BANDFMT_USHORT:
|
||||
CALL( unsigned short, nosign );
|
||||
break;
|
||||
|
||||
case IM_BANDFMT_SHORT:
|
||||
CALL( signed short, withsign );
|
||||
break;
|
||||
|
||||
case IM_BANDFMT_UINT:
|
||||
CALL( unsigned int, nosign );
|
||||
break;
|
||||
|
||||
case IM_BANDFMT_INT:
|
||||
CALL( signed int, withsign );
|
||||
break;
|
||||
|
||||
/*
|
||||
* Complex images are handled by doubling of bands.
|
||||
*/
|
||||
case IM_BANDFMT_FLOAT:
|
||||
case IM_BANDFMT_COMPLEX:
|
||||
CALL( float, fptypes );
|
||||
break;
|
||||
|
||||
case IM_BANDFMT_DOUBLE:
|
||||
case IM_BANDFMT_DPCOMPLEX:
|
||||
CALL( double, fptypes );
|
||||
break;
|
||||
|
||||
default:
|
||||
g_assert( 0 );
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
static void
|
||||
vips_interpolate_mbicubic_class_init( VipsInterpolateMbicubicClass *klass )
|
||||
{
|
||||
GObjectClass *gobject_class = G_OBJECT_CLASS( klass );
|
||||
VipsObjectClass *object_class = VIPS_OBJECT_CLASS( klass );
|
||||
VipsInterpolateClass *interpolate_class =
|
||||
VIPS_INTERPOLATE_CLASS( klass );
|
||||
|
||||
object_class->nickname = "mbicubic";
|
||||
object_class->description = _( "Halo-free mbicubic" );
|
||||
|
||||
interpolate_class->interpolate = vips_interpolate_mbicubic_interpolate;
|
||||
interpolate_class->window_size = 4;
|
||||
}
|
||||
|
||||
static void
|
||||
vips_interpolate_mbicubic_init( VipsInterpolateMbicubic *mbicubic )
|
||||
{
|
||||
}
|
||||
@ -76,6 +76,33 @@
|
||||
#endif
|
||||
#endif
|
||||
|
||||
/*
|
||||
* Various casts which assume that the data is already in range. (That
|
||||
* is, they are to be used with monotone samplers.)
|
||||
*/
|
||||
template <typename T> static T inline
|
||||
to_fptypes( const double val )
|
||||
{
|
||||
const T newval = val;
|
||||
return( newval );
|
||||
}
|
||||
|
||||
template <typename T> static T inline
|
||||
to_withsign( const double val )
|
||||
{
|
||||
const int sign_of_val = 2 * ( val >= 0. ) - 1;
|
||||
const int rounded_abs_val = .5 + sign_of_val * val;
|
||||
const T newval = sign_of_val * rounded_abs_val;
|
||||
return( newval );
|
||||
}
|
||||
|
||||
template <typename T> static T inline
|
||||
to_nosign( const double val )
|
||||
{
|
||||
const T newval = .5 + val;
|
||||
return( newval );
|
||||
}
|
||||
|
||||
/*
|
||||
* Various bilinear implementation templates. Note that no clampling
|
||||
* is used: There is an assumption that the data is such that
|
||||
|
||||
Loading…
Reference in New Issue
Block a user