Comment by Sylvain for "I'm sure the path to the picture is good"let me bet against that ;)getClass().getResource("lena.png").getPath() just try to replace that monster with an absolute path for starters, like:"/home/me/lena.png", or "c:/me/ma/miao/lena.png" // note : "/", not "\" (an empty image is quite typical for imread not finding it)

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