تحويل PDF إلى تدرج رمادي (أبيض وأسود).

Pages become images: text is no longer selectable (use the OCR tool to restore it). Up to 300 pages and 200 MB.

Each page is rendered with pdf.js, converted with the ITU-R BT.601 luminance formula (or a threshold for black and white) and placed in a new PDF at the original page size.

A 10-page colour brochure at 150 dpi becomes a grayscale PDF that prints without colour ink.