1 """GradationEffect for BLAST expect value distribution, It uses PIL
   2 """
   3 import Image, ImageDraw
   4 import math
   5 
   6 def yuv2rgb(Y,U,V):
   7     R = 1.164*(Y - 16) + 1.596*(V - 128)
   8     G = 1.164*(Y - 16) - 0.813*(V - 128) - 0.391*(U - 128)
   9     B = 1.164*(Y - 16) + 2.018*(U - 128)
  10     return tuple(map(int, (R,G,B)))
  11 
  12 def rgb2yuv(R,G,B):
  13     Y = (0.257 * R) + (0.504 * G) + (0.098 * B) + 16
  14     U = -(0.148 * R) - (0.291 * G) + (0.439 * B) + 128
  15     V = (0.439 * R) - (0.368 * G) - (0.071 * B) + 128
  16     return tuple(map(int, (Y,U,V)))
  17 
  18 def evalue2rgb(evalue):
  19     n = -math.log(evalue)/math.log(10)
  20     if n > 70:
  21         v = 255
  22     elif n < 5:
  23         v = 0
  24     else:
  25         v = int((n-5)*255/65)
  26     print evalue, n, v
  27     return yuv2rgb(10,50,v)
  28 
  29 def makeSampleImage():
  30     img = Image.new('RGB', (80,140), (255,255,255))
  31     draw = ImageDraw.Draw(img)
  32     for yline in range(128):
  33         color = yuv2rgb(10, 50, 255-yline*2)
  34         draw.line((5, yline+5, 35, yline+5), fill=color)
  35     draw.text((40, 2), '1e-70', fill='black')
  36     draw.text((40, 60), '1e-32', fill='black')
  37     draw.text((40, 126), '1e-5', fill='black')
  38     img.save('test.png',type='PNG')
  39 
  40 def makeEvalueDistribution():
  41     img = Image.new('RGB', (80,140), (255,255,255))
  42     draw = ImageDraw.Draw(img)
  43     y = 10
  44     for evalue in (1e-3, 1e-5, 1e-10, 1e-34, 1e-68, 1e-70, 1e-80):
  45         draw.rectangle((50, y, 70, y+10),fill=evalue2rgb(evalue))
  46         y+=15
  47     img.save('test.png',type='PNG')
  48 
  49 if __name__=='__main__':
  50     #makeSampleImage()
  51     makeEvalueDistribution()