promising but annoying bugs

I scanned the sixty pages on my Galaxy S3, the software is really good with perspective correction, but there is a problem with the portrait and landscape modes: Although this page is entirely the screen (landscape) the Photo is taken in portrait mode and therefore lacks both sides and the top and bottom are black bands. We arrive at around this problem by taking several pictures but the problem reappears in PDF export although everything was okay before export. The images are very degraded black and white (not grayscale) but PDFs are still quite large: it would use the JBIG2 compression on these black and white images. To improve so.