Converting One Image Format to Another using Ruby

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Insert the following code in your Ruby file.
 require 'rubygems'
 require 'RMagick'

img = Magick::Image.read("image.png").first
 img.write("image.jpg")                 # Writes a JPEG
 img.write("image.gif")                 # Writes a GIF
 img.write("JPG:image")                 # Writes a JPEG
 img.write("JPG:image.gif")             # Writes a JPEG

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