> Most pdf editors will put a square over the text
Redaction is usually a "Pro" feature in commercial PDF editors. People who use PDF's annotation feature to draw a big filled shape over the text/image to be redacted, don't know what they're doing and should be prepared for poor outcomes.
Adobe Acrobat and Foxit have "Pro" variants that redact properly, I'd love to know exactly how they do it. The open-source approach I'm familiar with, essentially converts the PDF to a flattened image and edits it to apply a colored shape over it. Example[1].
Redaction is usually a "Pro" feature in commercial PDF editors. People who use PDF's annotation feature to draw a big filled shape over the text/image to be redacted, don't know what they're doing and should be prepared for poor outcomes.
Adobe Acrobat and Foxit have "Pro" variants that redact properly, I'd love to know exactly how they do it. The open-source approach I'm familiar with, essentially converts the PDF to a flattened image and edits it to apply a colored shape over it. Example[1].
[1] https://github.com/firstlookmedia/pdf-redact-tools