This is an archival dump of old wiki content --- see for current material.
Please see

Scipy provides a command (imsave) to make a raster (png, jpg...) image from a 2D array, each pixel corresponding to one value of the array. Yet the image is black and white.

Here is a recipy to do this with Matplotlib, and use a colormap to give color to the image.

   1 from pylab import *
   2 from scipy import mgrid
   4 def imsave(filename, X, **kwargs):
   5     """ Homebrewed imsave to have nice colors... """
   6     figsize=(array(X.shape)/100.0)[::-1]
   7     rcParams.update({'figure.figsize':figsize})
   8     fig = figure(figsize=figsize)
   9     axes([0,0,1,1]) # Make the plot occupy the whole canvas
  10     axis('off')
  11     fig.set_size_inches(figsize)
  12     imshow(X,origin='lower', **kwargs)
  13     savefig(filename, facecolor='black', edgecolor='black', dpi=100)
  14     close(fig)
  17 X,Y=mgrid[-5:5:0.1,-5:5:0.1]
  18 Z=sin(X**2+Y**2+1e-4)/(X**2+Y**2+1e-4) # Create the data to be plotted
  19 imsave('imsave.png', Z, )


SciPy: Cookbook/Matplotlib/converting_a_matrix_to_a_raster_image (last edited 2015-10-24 17:48:24 by anonymous)