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POIs there a way to convert pyplot.imshow() object to numpy array?
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  1. POIs there a way to convert pyplot.imshow() object to numpy array?
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    copied!<p>I need to visualize a 2D numpy array. I am using pyplot for this. Here's the code:</p> <pre><code>import cv2 as cv import numpy as np from matplotlib import pyplot img = pyplot.imshow( radiance_val ) #radiance_val is a 2D numpy array of size = ( 512, 512 ) #filled with np.float32 values pyplot.show() </code></pre> <p>I am getting the output as expected.</p> <p>Now my question is, is there any way of converting "img" in the above code from pyplot type to numpy type. I need this so that I can load the visualization as opencv image and perform further processing on it. Im am using python 2.7, 32 bit.</p> <p>Kindly help</p> <p>Thank you</p> <hr> <p>EDIT 1: after Thorsten Kranz's solution</p> <pre><code>import numpy as np import cv2 as cv import matplotlib.pyplot as plt import PIL from cStringIO import StringIO frame1 = plt.gca() frame1.axes.get_xaxis().set_visible(False) frame1.axes.get_yaxis().set_visible(False) plt.imshow(np.random.random((10,10))) buffer_ = StringIO() plt.savefig( buffer_, format = "png", bbox_inches = 'tight', pad_inches = 0 ) buffer_.seek(0) image = PIL.Image.open( buffer_ ) ar = np.asarray(image) cv.imshow( 'a', ar ) cv.waitKey(0) cv.destroyAllWindows() </code></pre> <p>Here I am getting a runtime error from MS VC++ runtime library after the program terminates. My better guess is that it is because of the open "buffer_". But I am getting the required output.</p> <hr> <p>EDIT 2: closing the buffer using </p> <pre><code>buffer_.close() </code></pre> <p>did not solve the runtime error</p> <hr> <p><strong>FINAL EDIT</strong> : <a href="https://stackoverflow.com/questions/14880766/pyplot-cm-instance-is-producing-different-results-for-same-values-but-different"> <strong><em>SOLUTION</em></strong> </a></p>
 

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