How lighten & resize pdf in Draw

A pdf looks like it was made from photos that were then saved as a pdf. It is text only and there is no color (other than highlighted text) but the background of each page is dark. One page is attached.

Is there a way to lighten the background? If the background cannot be lightened, is there a way to lighten the whole document (so the text would be lighter as well)? If so, can that only be done page by page or can all pages be lightened at once?

Also, on some of the pages (but not all) the images do not cover the full page. I know that I can resize each image individually but does there happen to be a setting that would resize all of the images at the same time? I doubt there is such as setting but thought it worth asking.

Finally, while the file is only 35 pages, it is about 20 megs. Is there a way to reduce the size?


I think the best option is use an open source OCR to get the text Pdf Ocr Open source search

There is a brightness option for images on the sidebar, also there is a compress option on right-click. I think there is no way to work with several images on different pages, maybe saving as fodg (flat odg) and editing the options except compress, directly in the file, but for twenty pages is quicker doing with draw, page by page.

Is there a way to lighten the background?

Use Tools menu > color replacer (pipette) and try out several colors/options, so the in the end only the characters remain on (white) background.

the images do not cover the full page… that would resize all of the images

If the image is part of a bigger one Draw is not the the best utility for that. Nevertheless you may duplicate the bitmap and cut and resize it as you like it; so “a part” of the image is enlarged. Later all can be exported as one bitmap…

35 pages, it is about 20 megs
You may reduce the file size when exporting as PDF (define resolution).

The better way is to reduce the amount of colors or grayscale tones. That can better be done on a real image processing app like in batch mode, i.e. one step for several bitmaps. As a hint see the discussion on the same topic here: Change all graphics in all pages (View topic) • Apache OpenOffice Community Forum

The best way is - as m.a.riosv mentioned - to transform into a real text by an OCR app. I only can recommend proprietary apps for that like Abbyy Finereader or IRIS. Open source OCR apps regularly produce to many failures and the finetuning is nearly as hard as typing the complete text itself… :wink:




The PNG file was edited on the pipette function, later colors reduced to 8 grayscale tones on XnView (240 kB).
The ODT file (5,4 kB) was generated on IRIS. The result is so bad that simple retyping would make sense, wouldn’t it?