Remove a structured background from a PDF file

Discuss and share Pixelmator Pro resources such as templates, mockups, and tutorials.
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2022-10-17 18:36:50

Related to my post "Transform a scanned musical score image to (hard) black and white": I would like to remove the oddly structured background from the attached file. It is a single page from a PDF freely downloadable from the Internet, which is difficult to read on screen and almost impossible when printed.
Again, I can apply a B/W-Filter and tweak staturation and exposure and get good but not really perfect results. Using the automatic background removal feature in Pixelmator 3 does not give satisfactory results.

Again, what I'd like to achieve is: leave only the 100% black parts of the page and remove everything else or replace it by white. But I don't know HOW to achieve this. Any pointers are welcome.
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2022-10-18 09:43:08

Can we have an example snippet at least to play with?
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2022-10-18 10:04:39

by EllenM Can we have an example snippet at least to play with?
As I mentioned in my post I uploaded a file but somehow it didn't make it. Trying again.
Thanks!
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2022-10-18 10:13:57

by blacknwhite
As I mentioned in my post I uploaded a file but somehow it didn't make it. Trying again.
Thanks!
Hm, tried to upload the original PDF but that did not seem to work, again.
Trying to post a png exported from this pdf. Image

Maybe this worked.
You can find the original file on page 2 of this file:
https://www.agohq.org/wp-content/upload ... uction.pdf
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2023-07-08 16:38:28

Old request - I downloaded the pdf - exported the page to jpeg ( changing default resolution to 300 and 100%) in PixPro simple to select black text, invert selection and delete background. I fooled with making the black text "blacker" with copy and multiply with little success, "hard light" seemed better to me, with this result (output as png) FWIW

Image
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2023-07-08 16:49:30

by mccoytest in PixPro simple to select black text, invert selection and delete background.
OK, thanks. Meanwhile I learned that there are quite a couple of valid approaches to do this, each one adapted more or less to the source material.
But I am sorry to say, (a) I have never heard of this one, and this one is quite intriguing, and (b) I have absoultely no idea what you were doing, from your description. How exactly to select black text, invert selection and delete background?
Could you please go into some more detail on what exactly you were doing to achieve this adimirable result? Thanks a lot!
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2023-07-09 15:10:35

Sure. As I said, I select a black color range by clicking on some black text and selecting. I inverted the selection and deleted all the background leaving only text. I created a new layer and filled it with white, and moved it below the text layer. Back to the text layer I duplicated it and tried various blend modes to "blacken" the text. Then submitted the solution here.

But today I had a difficult time selecting all the black text. So I selected all the background by color range and deleted it leaving just the black text and duplicated it. Created the white background below the text and fooled around with blend modes to create this:

Image