PDF books and articles found online are usually poorly rendered on small e-readers (e.g. Kindle Oasis), as a whole PDF page is displayed on the small screen.
This lib uses OCR to correct the skewed angle of the page, crop around the text and re-paginate; as to optimize for the best reading experience on small e-readers.
The code was initially written in 2018 in Java, alongside an online converter website that I decided to take down as it would cost quite a bit (OCR and image processing being quite resource-intensive). I also couldn't maintain it as I was working full time.
Therefore, the project probably needs a bit of a cleanup.
The unit tests using full PDF books can not be shared publicly, so I will re-add them later, using only individual pages rather than complete books.
sudo apt-get install tesseract-ocrThe data in tessdata/ is found on https://github.com/tesseract-ocr/tessdata_best
RequestConfig requestConfig = RequestConfig
.builder()
.pdfFile(file)
.minPage(minPage)
.maxPage(maxPage)
.correctAngle(true)
.build();
Processor processor = new Processor(requestConfig);
processor.process();
processor.joinThread();
File outputFile = processor.writeToPDFFile(fileName + "_optimized.pdf");Move to Gradle- Re-add unit tests that can be shared publicly, adapt the other ones
- Add language as a parameter
- Create a user-friendly runnable
- Move to Kotlin
- Finish picture detection