JPEG200 products provided by RomSoft. Here you find a C++ DLL implementation of JPEG2000 Part 1 standard (ISO/IEC 15444-1) and a Photoshop plugin for JPEG2000 and J2K files

Reader Petrut D. had this to say:

One of the fastest JPEG2000 codecs out there. The Intel IPP library helped a lot with performance. I also tried the Photoshop plug-in, and managed to open all the test files from http://www.crc.ricoh.com/~gormish/jpeg2000conformance/J2KP4files/ part 0 and part 1. The plug-in handled JP2 and J2K images from 1 bit to 16 bit signed/unsigned flowlessly. Highly recomend the C++ DLL and the Photoshop plugin.

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