4 ms·
It can be not just metadata. There are plenty of ways to hide 128 bits of ID in a long enough pdf. White rectangles on white background, slightly non-black colo
by jojobas 2y ago
It can be not just metadata. There are plenty of ways to hide 128 bits of ID in a long enough pdf. White rectangles on white background, slightly non-black coloured pixels here and there, you name it. Many can even survive a print-and-scan.
- squarefoot 2y agoIn theory turning everything into an image then compressing using lossy formats aiming at very low size should mask subtle visual artifacts, but yeah, steganography could be implemented in many other ways, such as slightly different fonts (sizes, line spacing, orientation, etc). I wonder if AI, could be used to analyze and find those details by comparing potentially watermarked identical documents.