Sumatra PDF is a PDF, ePub, MOBI, CHM, XPS, DjVu, CBZ, CBR reader for Windows

Highlight non-text areas

It would be nice to have the possibility to highlight non-text areas, such as scanned text or image parts.
I frequently receive pdf files that have been scanned, with no OCR, and I wish I could highlight text on these files anyway (even if not stored as text, but as an image).
I understant it would be more difficult thant just highlighting text…
How feasible is this ? Would it be useful to other people too ?

That was always possible and before enhancing to PDF only annotations could even be done on plain text or some other formats, however is now only possible in PDF file, since no extra smx file is used.

Annotation trigger is same as for a line of text. but the MuPDF “highlight” annotation exactly same as for text is NOT a simple rectangle it is more like a flattened globe. Plain Circles & Rectangles are a future enhancement. and you can use “underline” on an image or even in space.

Make your selection of area or image and press A or use the menu commands as for text etc.

Remember to make a selection (other than text) for zoom, print area, copy content or annotate you use CTRL key combined with left mouse drag or for an image object or single word simply double click those to select.

Great ! I was missing out this feature !
Actually, I didn’t know you could make a selection like this (CTRL key + mouse drag).
(I should have read the manual).
Waiting for the plain circles or rectangles enhancement, but this is already very good.
Thanks !