comparison pycaptcha/Captcha/Visual/Text.py @ 87:4775b4195b4b

code pour la generation de captchas
author goldfinger
date Thu, 11 Feb 2010 05:09:46 -0500
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children 25b7c1f20949
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86:b3d76ebf2fac 87:4775b4195b4b
1 """ Captcha.Visual.Text
2
3 Text generation for visual CAPTCHAs.
4 """
5 #
6 # PyCAPTCHA Package
7 # Copyright (C) 2004 Micah Dowty <micah@navi.cx>
8 #
9
10 import random, os
11 from Captcha import Visual, File
12 import ImageFont, ImageDraw
13
14
15 class FontFactory(File.RandomFileFactory):
16 """Picks random fonts and/or sizes from a given list.
17 'sizes' can be a single size or a (min,max) tuple.
18 If any of the given files are directories, all *.ttf found
19 in that directory will be added.
20 """
21 extensions = [".ttf"]
22 basePath = "fonts"
23
24 # arguments variables a modifier pour mettre le chemin vers les fontes.
25 def __init__(self, sizes, *fileNames):
26 File.RandomFileFactory.__init__(self, *fileNames)
27
28 if type(sizes) is tuple:
29 self.minSize = sizes[0]
30 self.maxSize = sizes[1]
31 else:
32 self.minSize = sizes
33 self.maxSize = sizes
34
35 def pick(self):
36 """Returns a (fileName, size) tuple that can be passed to ImageFont.truetype()"""
37 fileName = File.RandomFileFactory.pick(self)
38 size = int(random.uniform(self.minSize, self.maxSize) + 0.5)
39 return (fileName, size)
40
41 # Predefined font factories
42 defaultFontFactory = FontFactory(25, "vera", "others")
43 #defaultFontFactory = FontFactory((30, 40), "vera")
44
45 class TextLayer(Visual.Layer):
46 """Represents a piece of text rendered within the image.
47 Alignment is given such that (0,0) places the text in the
48 top-left corner and (1,1) places it in the bottom-left.
49
50 The font and alignment are optional, if not specified one is
51 chosen randomly. If no font factory is specified, the default is used.
52 """
53 def __init__(self, text,
54 alignment = None,
55 font = None,
56 fontFactory = None,
57 textColor = "white",
58 borderSize = 0,
59 borderColor = None,
60 ):
61 if fontFactory is None:
62 global defaultFontFactory
63 fontFactory = defaultFontFactory
64
65 if font is None:
66 font = fontFactory.pick()
67
68 if alignment is None:
69 alignment = (random.uniform(0,1),
70 random.uniform(0,1))
71
72 self.text = text
73 self.alignment = alignment
74 self.font = font
75 self.textColor = textColor
76 self.borderSize = borderSize
77 self.borderColor = borderColor
78
79 def render(self, img):
80 font = ImageFont.truetype(*self.font)
81 textSize = font.getsize(self.text)
82 draw = ImageDraw.Draw(img)
83
84 # Find the text's origin given our alignment and current image size
85 x = int((img.size[0] - textSize[0] - self.borderSize*2) * self.alignment[0] + 0.5)
86 y = int((img.size[1] - textSize[1] - self.borderSize*2) * self.alignment[1] + 0.5)
87
88 # Draw the border if we need one. This is slow and ugly, but there doesn't
89 # seem to be a better way with PIL.
90 if self.borderSize > 0:
91 for bx in (-1,0,1):
92 for by in (-1,0,1):
93 if bx and by:
94 draw.text((x + bx * self.borderSize,
95 y + by * self.borderSize),
96 self.text, font=font, fill=self.borderColor)
97
98 # And the text itself...
99 draw.text((x,y), self.text, font=font, fill=self.textColor)
100
101 ### The End ###