JPEG 2000 support using OpenJPEG library.
- Add read/write support to JP2/J2K format for Gray/RGB(A)/CMYK images @8/16-bits
- Read test case images generated by Photoshop
The plugin has the following limitations:
- Resolution is not set (JP2_RES box is marked "For the future" in jp2.h)
- Metadata are not set (as with resolution)
Closes#13
