$Id: a07cf90837a3c4373b82d6724b97593810766af7 $
The hidden image appeared. It was a photograph of a young woman—Lena—sitting in a hospital bed. She was holding a copy of Digital Image Processing, 3rd Edition . And she was smiling. Scribbled on the cover in marker was a single phrase:
— Ghost With trembling hands, Aris pulled the final commit. It was an image file: lena_512_ghost.png . digital image processing 3rd edition solution github
But then, he noticed something odd. A single commit in the repository’s history. A user named PixelGhost_99 had solved Problem 8.9—the one about image segmentation using watershed algorithms—in a way that was… impossible. The hidden image appeared
He scrolled to Problem 5.18—the one about Wiener filtering in the presence of additive noise. He had spent a week crafting that problem. The solution on GitHub was not only correct, it was elegant . It used a spectral subtraction trick he hadn't even taught yet. And she was smiling
Yes, I broke it on purpose for this demonstation!↩︎