Investigate JPG2000 check_boxes

[piponazo]

As discussed in #1016 the new boxes_check function introduced looks a little arbitrary and it would be good to check what the JPEG2000 specification exactly says about it.

[piponazo]

This link seems to provide a good introduction about the JPEG2000 structure: https://github.com/plroit/Skyreach/wiki/Introduction-to-JPEG2000-Structure-and-Layout

[clanmills]

That documentation looks great. Very nice graphics.

I think ISOBMFF (including HEIF, AVIF, Mpeg4, CR3) and JPEG2000 are all very similar. One implementation can probably read all those formats. I was willing to undertake that as the "one big new feature" in Exiv2 v0.27.3. I ran into hostility from people I from whom I expect encouragement, not obstruction. #1066 Laurent Clevy @lclevy/canon_cr is an expert. Phil (Harvey) speaks very highly of him.

It would be really good to get ISOBMFF into Exiv2 on both master and 0.27-maintenace. I'll be happy to help you.

[piponazo]

Hi Robin. I was taking yesterday a look to the list of open issues and I was investigating a bit about this one. I have to say that I was a bit depressed after finding out that there is not much information about how the JPEG2000 metadata is organised ...

Now that you mentioned ISOBMFF, I have other place where to look at. I will investigate in my spare time. However, I cannot commit myself to do it for the next release 0.27.3. I'll work on it and I'll let you know if I advance enough in the next days to reconsider that ;)

[clanmills]

Good stuff. I'm not thinking about ISOBMFF in v0.27.3. This feature is good enough to justify doing Exiv2 v0.27.4 when it's ready.

[clanmills]

@piponazo I've done quite a lot of work on ISOBMFF for the book. It's very much work-in-progress at the moment. I hope it will be ready for review by Christmas.

When will it be 100% done, off to the printers. Probably Spring. For sure, before LGM which is expected to be May 2021.

[clanmills]

I've opened issue #1525 to investigating removing jp2image.cpp and replacing it with bmffimage.cpp