Hi,
I am trying to create an image from an array using PIL, numpy and a
colourmap from matplotlib.
I got the colourmap by using ipython and the following code
colourmap = []
for i in xrange(256):
r,g,b,a = cm.jet(i)
r = int(round((r * 255),0))
g = int(round((g * 255),0))
b = int(round((b* 255),0))
colourmap.append((r,g,b))
The following is used to plot an array:
def array2image(array, scale="log", filename="tmp"):
# create image of the correct size
new_image = Image.new("RGB", array.shape)
# scan through a matrix and use Image.putdata() to put it in.
x_size, y_size = array.shape
largest = array.max()
a_list = array.ravel()
new_list = []
for x in a_list:
if x == 0:
new_list.append((0,0,0))
else:
value = (log(x)/log(largest))*255
value = int(round(value,0))
value = blues_colourmap[value]
#print value
new_list.append(value)
new_image.putdata(new_list)
new_image.save(filename+".bmp")
The image that is outputted is certainly correct for the data, however
it is just no where near as "pretty" as the image you get from using
plt.imshow(am_array)
I'd like to get something that looks the same. I don't think the
problems are because of the colourmap but rather because of my log
scaling. Could someone please explain how matplotlib scales the image
to make it look so nice?
Regards,
Ciarán
------------------------------------------------------------------------------
Download Intel® Parallel Studio Eval
Try the new software tools for yourself. Speed compiling, find bugs
proactively, and fine-tune applications for parallel performance.
See why Intel Parallel Studio got high marks during beta.
http://p.sf.net/sfu/intel-sw-dev
_______________________________________________
Matplotlib-users mailing list
Matplotlib-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/matplotlib-users
