I can confirm that the author's approach doesn't work well for photographed pages. I took a photograph[0] of a page of notes, and due to the shadow, the results

I can confirm that the author's approach doesn't work well for photographed pages. I took a photograph[0] of a page of notes, and due to the shadow, the results[1] were very unsatisfactory. [0]: https://i.imgur.com/CLZHshT.jpg https://i.imgur.com/CLZHshT.jpg [1]: https://i.imgur.com/rrwca0m.jpg https://i.imgur.com/rrwca0m.jpg