If you want to extract highlighted text from PDF file as a plain text file, then this post covers some good free PDF Highlight Extractor software to do that.

" AlterPDF " is free software that allows you to convert such PDF files to images and extract text and images from files.

Engineer Simon Wilson has released `` OCR PDFs and images directly in your browser,' ' which allows you to extract text from image files such as PNG, JPEG, GIF, and PDF files using OCR (optical ...

To extract the text from the image, you need to save the image as a PDF file. An Open dialog box will appear; click the saved PDF file, then click Open.

Now click on PDFs in the far-left column and select Extract PDF Text from the second column. Drag and drop Extract PDF Text into the space to the right, where you dragged Find Files and Folders.

If you're wanting to convert an image into text, Google Docs has a powerful Optical Character Recognition feature built right in. Here's how to make it work.