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authorAaron LI <aly@aaronly.me>2017-11-03 18:33:45 +0800
committerAaron LI <aly@aaronly.me>2017-11-03 18:33:45 +0800
commit626a1a3c73ee1395712002cf7d90c6d00b1cc3bf (patch)
treec39e4ddaef695e57c357a8b609d1b4301c916b7a /python
parent244ad1d73e90823281e5116a3aed5ea6ee0d5128 (diff)
downloadatoolbox-626a1a3c73ee1395712002cf7d90c6d00b1cc3bf.tar.bz2
Remove python/force_field_transform.py
Diffstat (limited to 'python')
-rw-r--r--python/force_field_transform.py126
1 files changed, 0 insertions, 126 deletions
diff --git a/python/force_field_transform.py b/python/force_field_transform.py
deleted file mode 100644
index 2b185c8..0000000
--- a/python/force_field_transform.py
+++ /dev/null
@@ -1,126 +0,0 @@
-# -*- coding: utf -*-
-#
-# Force field transform (Hurley et al., 2002, 2005)
-#
-
-"""
-Force field transform
-"""
-
-import sys
-import time
-import numpy as np
-
-
-def force(p1, p2):
- """
- The force between two points of the image.
-
- Arguments:
- p1, p2: (value, x, y)
-
- Return:
- # (force, angle): value and direction of the force.
- # angle: (-pi, pi], with respect to p1.
- (f_x, f_y): x and y components of the force
- """
- v1, x1, y1 = p1
- v2, x2, y2 = p2
- #force = v1*v2 / ((x1-x2)**2 + (y1-y2)**2)
- #angle = np.atan2(y2-y1, x2-x1)
- #return (force, angle)
- f_x = v1 * v2 * (x2-x1) / ((x2-x1)**2 + (y2-y1)**2)**1.5
- f_y = v1 * v2 * (y2-y1) / ((x2-x1)**2 + (y2-y1)**2)**1.5
- return (f_x, f_y)
-
-
-def force_array(p0, img):
- """
- The forces between the input point with respect to the image.
-
- Arguments:
- p0: (x, y), note (x, y) start with zero.
- img: input image, a numpy array
-
- Return:
- (f_x, f_y): x and y components of the forces of the same size
- of the input image
- """
- x0, y0 = p0
- v0 = img[y0, x0]
- img[y0, x0] = 0.0
- x, y = np.meshgrid(range(img.shape[1]), range(img.shape[0]))
- x[y0, x0] = -1
- y[y0, x0] = -1
- f_x = v0 * img * (x-x0) / ((x-x0)**2 + (y-y0)**2)**1.5
- f_y = v0 * img * (y-y0) / ((x-x0)**2 + (y-y0)**2)**1.5
- return (f_x, f_y)
-
-
-def vector_add(v1, v2):
- """
- Add two vectors and return the results.
-
- Arguments:
- v1, v2: two input vectors of format (f_x, f_y)
-
- Return:
- (F_x, F_y)
- """
- f1_x, f1_y = v1
- f2_x, f2_y = v2
- return (f1_x+f2_x, f1_y+f2_y)
-
-
-def force_summation(pixel, img):
- """
- Calculate the resulting force of the specified pixel with respect to
- the image.
-
- Argument:
- pixel: the position (x, y) of the pixel to be calculated
- img: the input image
-
- Return:
- (F_x, F_y): x and y components of the resulting force.
- """
- img = np.array(img)
- x0, y0 = pixel
- f_x, f_y = force_array((x0, y0), img)
- return (f_x.sum(), f_y.sum())
-
-
-def force_field_transform(img):
- """
- Perform the "force field transform" on the input image.
-
- Arguments:
- img: input 2D image
-
- Return:
- (amplitudes, angles)
- amplitudes: the amplitudes of the resulting forces of each pixel
- angles: the directions of the resulting forces of each pixel,
- in unit radian.
- """
- img = np.array(img)
- amplitudes = np.zeros(img.shape)
- angles = np.zeros(img.shape)
- rows, cols = img.shape
- t0 = time.time()
- t_p = t0 + 30 # in 30 seconds
- for y in range(rows):
- for x in range(cols):
- t1 = time.time()
- if t1 >= t_p:
- percent = 100 * (y*cols + x + 1) / (rows * cols)
- print("progress: %.3f%%; %.1f min" % (percent, (t1-t0)/60.0),
- file=sys.stderr)
- t_p += 30 # in 30 seconds
- f_x, f_y = force_array((x, y), img)
- F_x, F_y = f_x.sum(), f_y.sum()
- amplitudes[y, x] = np.sqrt(F_x**2 + F_y**2)
- angles[y, x] = np.math.atan2(F_y, F_x)
- return (amplitudes, angles)
-
-