PDF Extract no longer extracts all images under JDK14

[JamzTheMan]

Describe the bug
PDF Extractor can no longer write out certain images like jpeg2000.

To Reproduce
Steps to reproduce the behavior:

1. Attempt to extract out various PDF's (need to find a PDF example that doesn't have copy write material) but for my tests I tried various Paizo PDF's and Page_13.pdf from @Phergus (but hesitant to post as that is also probably copyrighted material)

Expected behavior
All images in PDF should extract as it does using MapTool 1.7.x or TokenTool 2.1.

MapTool Info

• Version: DEVELOP branch
• Install: New, Upgrade [previous version], or JAR [Java Version]

Desktop (please complete the following information):

• OS: ALL
• Version ALL

Additional context
I've tried to capture failed Image.io write of jpg and write image as png instead which fixes some issues but several images are still not being written out. Further debugging needs to done.

Can compare more with TokenTool DEVELOP branch as that now also uses JDK14 and uses virtually same code except images are stored in memory (because only one page worth of images is shown at a time vs extract of whole PDF)

[Phergus]

Next release will be using Java 16. With the updated ImageIO plugins from #2495 I am seeing the correct results with PDF import on the ones I've tried. Still need to test against the Paizo files.

[Phergus]

The Paizo PDFs are still an issue and TT 2.2 extracts more images from other PDFs.

[Zahariel]

Has this been addressed at all? It still doesn't seem to work very well with Paizo's files; it manages to extract "some" images but it's not at all reliable, even with One File Per Chapter files that aren't 600 pages long. (I'm ok with it not working well with a 600 page PDF!)

[Phergus]

Nothing so far. Someone is going to have to get up to speed on the PDF extraction code and do some serious debugging.