Comment by crazygringo

I think you are misunderstanding. The pipeline is e.g.:

Scan (600 dpi) > MRC (600 dpi) > OCR (600 dpi) > Downsample (150 dpi) > Save to PDF (150 dpi)

The image is saved in raster format at 150 dpi. That's the document, but not at the original scanning resolution. If you performed MRC and OCR at the 150 dpi level, you'd get different/worse results than were originally gotten at 600 dpi. Which is why you always OCR before downsampling, and you downsample for smaller files.

This isn't changing anything about the Snopes article. It just explains why if you run MRC/OCR at the PDF resolution, you won't deterministically reproduce it because it's not the resolution it was originally run at.

You do understand that this OCR is only for being able to search and highlight text? It's not changing what's displayed. That's still the pixels.