Mercurial > ift6266

annotate transformations/affine_transform.py @ 39:17caecc92544

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
affine transformation using PIL
author Razvan Pascanu <r.pascanu@gmail.com>
date Tue, 02 Feb 2010 21:17:11 -0500
parents
children 81b9567ec4ae
rev   line source
39
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
1 #!/usr/bin/python
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
2 # coding: utf-8
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
3
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
4 '''
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
5 Simple implementation of random affine transformations based on the Python
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
6 Imaging Module affine transformations.
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
7
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
8
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
9 Author: Razvan Pascanu
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
10 '''
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
11
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
12 import numpy, Image
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
13
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
14
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
15
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
16 class AffineTransformation():
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
17 def __init__( self, shape = (32,32), seed = None):
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
18 self.shape = shape
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
19 self.rng = numpy.random.RandomState(seed)
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
20
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
21 def transform(self,NIST_image):
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
22
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
23 im = Image.fromarray( \
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
24 numpy.asarray(\
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
25 NIST_image.reshape(self.shape), dtype='uint8'))
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
26 # generate random affine transformation
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
27 # a point (x',y') of the new image corresponds to (x,y) of the old
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
28 # image where :
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
29 # x' = params[0]*x + params[1]*y + params[2]
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
30 # y' = params[3]*x + params[4]*y _ params[5]
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
31
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
32 # the ranges are set manually as to look acceptable
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
33 params = self.rng.uniform(size = 6) -.5
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
34 params[2] *= 8.
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
35 params[5] *= 8.
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
36 params[0] = 1. + params[0]*0.4
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
37 params[3] = 0. + params[3]*0.4
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
38 params[1] = 0 + params[1]*0.4
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
39 params[4] = 1 + params[4]*0.4
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
40
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
41 print params
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
42 nwim = im.transform( (32,32), Image.AFFINE, params)
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
43 return numpy.asarray(nwim)
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
44
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
45
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
46
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
47 if __name__ =='__main__':
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
48 print 'random test'
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
49
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
50 from pylearn.io import filetensor as ft
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
51 import pylab
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
52
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
53 datapath = '/data/lisa/data/nist/by_class/'
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
54
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
55 f = open(datapath+'digits/digits_train_data.ft')
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
56 d = ft.read(f)
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
57 f.close()
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
58
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
59
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
60 transformer = AffineTransformation()
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
61 id = numpy.random.randint(30)
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
62
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
63 pylab.figure()
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
64 pylab.imshow(d[id].reshape((32,32)))
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
65 pylab.figure()
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
66 pylab.imshow(transformer.transform(d[id]).reshape((32,32)))
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
67
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
68 pylab.show()
17caecc92544 affine transformation using PIL
Razvan Pascanu <r.pascanu@gmail.com>
parents:
diff changeset
69