I have a PDF document with text and basic graphics (squares, circles, thought bubbles, etc.) behind the text. My goal is to change the colors of these shapes.
Here's what I've tried:
I don't have access to the original (non-PDF) file, so I don't know where to go from here. Any help would be greatly appreciated! :)
Just to add to your comment, you can open your PDF directly in Photoshop if the PDF is made of raster images and texts anyway.
Just make sure you select the real resolution it was created for. Usually for printing, it's 300ppi. You will see if the resolution you chose is too high, the image will look blurry when you look at it at 100%.
Then you can change the color of your shapes using the tools you prefer. It's difficult to give you any advice on this without knowing what the file looks like.
If you plan to use this document for printing, you might want to "rebuild" it by separating the pictures (or shapes that are stuck together, and probably raster images) and keep the texts as vectors. And then re-import your new colored images into your vector file. This way, you will keep the perfect quality of your texts and that can always be useful later if you want to make other changes.
For example, open the PDF with Illustrator, copy the pictures/shapes only into Photoshop and do the color changes. Then re-insert these images into the Illustrator file and resave all this as PDF.