wassname/scikit-image
1
0
Fork 0
mirror of https://github.com/wassname/scikit-image.git synced 2026-07-18 12:40:14 +08:00
Code Issues Packages Projects Releases Wiki Activity

Move bilinear interpolation code to shared package

Browse Source
This commit is contained in:
Johannes Schönberger
2012-08-21 08:32:20 +02:00
parent d87ed28d8e
commit 824997af0a
7 changed files with 118 additions and 106 deletions
Download Patch File Download Diff File Expand all files Collapse all files
skimage/transform/_project.pxd → skimage/_shared/interpolation.pxd
+5 -3
View File
@@ -1,7 +1,9 @@
cimport numpy as np
import numpy as np
cdef inline double bilinear_interpolation(double* image, int rows, int cols,
double r, double c, char mode,
double cval=*)
cdef inline double get_pixel(double* image, int rows, int cols, int r, int c,
char mode, double cval=*)
cdef inline int coord_map(int dim, int coord, char mode)
skimage/_shared/interpolation.pyx
+104
View File
@@ -0,0 +1,104 @@
#cython: cdivison=True
#cython: boundscheck=False
#cython: nonecheck=False
#cython: wraparound=False
from libc.math cimport ceil, floor
cdef inline double bilinear_interpolation(double* image, int rows, int cols,
double r, double c, char mode,
double cval=0):
"""Bilinear interpolation at a given position in the image.
Parameters
----------
image : double array
Input image.
rows, cols: int
Shape of image.
r, c : int
Position at which to interpolate.
mode : {'C', 'W', 'M'}
Wrapping mode. Constant, Wrap or Mirror.
cval : double
Constant value to use for constant mode.
"""
cdef double dr, dc
cdef int minr, minc, maxr, maxc
minr = <int>floor(r)
minc = <int>floor(c)
maxr = <int>ceil(r)
maxc = <int>ceil(c)
dr = r - minr
dc = c - minc
top = (1 - dc) * get_pixel(image, rows, cols, minr, minc, mode, cval) \
+ dc * get_pixel(image, rows, cols, minr, maxc, mode, cval)
bottom = (1 - dc) * get_pixel(image, rows, cols, maxr, minc, mode, cval) \
+ dc * get_pixel(image, rows, cols, maxr, maxc, mode, cval)
return (1 - dr) * top + dr * bottom
cdef inline double get_pixel(double* image, int rows, int cols, int r, int c,
char mode, double cval=0):
"""Get a pixel from the image, taking wrapping mode into consideration.
Parameters
----------
image : double array
Input image.
rows, cols: int
Shape of image.
r, c : int
Position at which to get the pixel.
mode : {'C', 'W', 'M'}
Wrapping mode. Constant, Wrap or Mirror.
cval : double
Constant value to use for constant mode.
"""
if mode == 'C':
if (r < 0) or (r > rows - 1) or (c < 0) or (c > cols - 1):
return cval
else:
return image[r * cols + c]
else:
return image[coord_map(rows, r, mode) * cols + coord_map(cols, c, mode)]
cdef inline int coord_map(int dim, int coord, char mode):
"""
Wrap a coordinate, according to a given mode.
Parameters
----------
dim : int
Maximum coordinate.
coord : int
Coord provided by user. May be < 0 or > dim.
mode : {'W', 'M'}
Whether to wrap or mirror the coordinate if it
falls outside [0, dim).
"""
dim = dim - 1
if mode == 'M': # mirror
if (coord < 0):
# How many times times does the coordinate wrap?
if (<int>(-coord / dim) % 2 != 0):
return dim - <int>(-coord % dim)
else:
return <int>(-coord % dim)
elif (coord > dim):
if (<int>(coord / dim) % 2 != 0):
return <int>(dim - (coord % dim))
else:
return <int>(coord % dim)
elif mode == 'W': # wrap
if (coord < 0):
return <int>(dim - (-coord % dim))
elif (coord > dim):
return <int>(coord % dim)
return coord
skimage/_shared/setup.py
+5
View File
@@ -13,6 +13,11 @@ def configuration(parent_package='', top_path=None):
config = Configuration('_shared', parent_package, top_path)
config.add_data_dir('tests')
cython(['interpolation.pyx'], working_path=base_path)
config.add_extension('interpolation', sources=['interpolation.c'],
include_dirs=[get_numpy_include_dirs()])
return config
skimage/feature/_texture.pyx
+1 -1
View File
@@ -5,7 +5,7 @@
import numpy as np
cimport numpy as np
from libc.math cimport sin, cos, abs
from skimage.transform._project cimport bilinear_interpolation
from skimage._shared.interpolation cimport bilinear_interpolation
def _glcm_loop(np.ndarray[dtype=np.uint8_t, ndim=2,
skimage/setup.py
+1
View File
@@ -6,6 +6,7 @@ def configuration(parent_package='', top_path=None):
config = Configuration('skimage', parent_package, top_path)
config.add_subpackage('_shared')
config.add_subpackage('color')
config.add_subpackage('data')
config.add_subpackage('draw')
skimage/transform/_project.pyx
+1 -101
View File
@@ -5,107 +5,7 @@
cimport numpy as np
import numpy as np
from cython.operator import dereference
from libc.math cimport ceil, floor
cdef inline double bilinear_interpolation(double* image, int rows, int cols,
double r, double c, char mode,
double cval=0):
"""Bilinear interpolation at a given position in the image.
Parameters
----------
image : double array
Input image.
rows, cols: int
Shape of image.
r, c : int
Position at which to interpolate.
mode : {'C', 'W', 'M'}
Wrapping mode. Constant, Wrap or Mirror.
cval : double
Constant value to use for constant mode.
"""
cdef double dr, dc
cdef int minr, minc, maxr, maxc
minr = <int>floor(r)
minc = <int>floor(c)
maxr = <int>ceil(r)
maxc = <int>ceil(c)
dr = r - minr
dc = c - minc
top = (1 - dc) * get_pixel(image, rows, cols, minr, minc, mode, cval) \
+ dc * get_pixel(image, rows, cols, minr, maxc, mode, cval)
bottom = (1 - dc) * get_pixel(image, rows, cols, maxr, minc, mode, cval) \
+ dc * get_pixel(image, rows, cols, maxr, maxc, mode, cval)
return (1 - dr) * top + dr * bottom
cdef inline double get_pixel(double* image, int rows, int cols, int r, int c,
char mode, double cval=0):
"""Get a pixel from the image, taking wrapping mode into consideration.
Parameters
----------
image : double array
Input image.
rows, cols: int
Shape of image.
r, c : int
Position at which to get the pixel.
mode : {'C', 'W', 'M'}
Wrapping mode. Constant, Wrap or Mirror.
cval : double
Constant value to use for constant mode.
"""
if mode == 'C':
if (r < 0) or (r > rows - 1) or (c < 0) or (c > cols - 1):
return cval
else:
return image[r * cols + c]
else:
return image[coord_map(rows, r, mode) * cols + coord_map(cols, c, mode)]
cdef inline int coord_map(int dim, int coord, char mode):
"""
Wrap a coordinate, according to a given mode.
Parameters
----------
dim : int
Maximum coordinate.
coord : int
Coord provided by user. May be < 0 or > dim.
mode : {'W', 'M'}
Whether to wrap or mirror the coordinate if it
falls outside [0, dim).
"""
dim = dim - 1
if mode == 'M': # mirror
if (coord < 0):
# How many times times does the coordinate wrap?
if (<int>(-coord / dim) % 2 != 0):
return dim - <int>(-coord % dim)
else:
return <int>(-coord % dim)
elif (coord > dim):
if (<int>(coord / dim) % 2 != 0):
return <int>(dim - (coord % dim))
else:
return <int>(coord % dim)
elif mode == 'W': # wrap
if (coord < 0):
return <int>(dim - (-coord % dim))
elif (coord > dim):
return <int>(coord % dim)
return coord
from skimage._shared.interpolation cimport bilinear_interpolation
cdef inline _matrix_transform(double x, double y, double* H, double *x_,
skimage/transform/setup.py
+1 -1
View File
@@ -20,7 +20,7 @@ def configuration(parent_package='', top_path=None):
include_dirs=[get_numpy_include_dirs()])
config.add_extension('_project', sources=['_project.c'],
include_dirs=[get_numpy_include_dirs()])
include_dirs=[get_numpy_include_dirs(), '../_shared'])
return config