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POUsing PIL and NumPy to convert an image to Lab array, modify the values and then convert back
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  1. POUsing PIL and NumPy to convert an image to Lab array, modify the values and then convert back
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    copied!<p>I am trying to convert a PIL image into an array using NumPy. I then want to convert that array into Lab values, modify the values and then convert the array back in to an image and save the image. I have the following code:</p> <pre><code>import Image, color, numpy # Open the image file src = Image.open("face-him.jpg") # Attempt to ensure image is RGB src = src.convert(mode="RGB") # Create array of image using numpy srcArray = numpy.asarray(src) # Convert array from RGB into Lab srcArray = color.rgb2lab(srcArray) # Modify array here # Convert array back into Lab end = color.lab2rgb(srcArray) # Create image from array final = Image.fromarray(end, "RGB") # Save final.save("out.jpg") </code></pre> <p>This code is dependent on PIL, NumPy and <em>color</em>. color can be found in the SciPy trunk <a href="http://svn.scipy.org/svn/scipy/tags/pre_org/Lib/image/color.py" rel="noreferrer">here</a>. I downloaded the color.py file along with certain <a href="http://svn.scipy.org/svn/scipy/tags/pre_org/Lib/image/" rel="noreferrer">colordata .txt files</a>. I modified the color.py so that it can run independently from the SciPy source and it all <em>seems</em> to work fine - values in the array are changed when I run conversions.</p> <p>My problem is that when I run the above code which simply converts an image to Lab, then back to RGB and saves it I get the following image back:</p> <p><img src="https://imgur.com/kI2WY.jpg" alt="alt text"></p> <p>What is going wrong? Is it the fact I am using the functions from color.py?</p> <p>For reference:<br> Source Image - <a href="https://imgur.com/81SSp.jpg" rel="noreferrer">face-him.jpg</a><br> All source files required to test - <a href="http://www.maxnov.com/colour-test.zip" rel="noreferrer">colour-test.zip</a></p>
 

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