Openjpeg 2.5 released last Friday is the latest update to the open source JPEG 2000 image library. It is worth noting that this new version of BSD 2-clause library now supports high-throughput "htj2k" decoding. In order to improve the efficiency of JPEG decoding, the cost of j22000 is slightly lower.
Htj2k replaces the JPEG 2000 standard block encoder with an alternative encoder focusing on vector performance. The high-throughput JPEG 2000 specification Part 15 (ISO / IEC 15444-1) was only determined in 2019.
Htj2k is described as providing an "order of magnitude increase" for JPEG 2000, thanks to its new HT block encoder, which improves the efficiency by about 10 times for those medium to high compression bit rates and 30 times for lossless coding (although the coding efficiency is 5-10% lower than the original j2k-1 encoder).
Through the openjph project, we had a reference open source implementation of htj2k before, but now with the launch of openjpeg 2.5, we have additional open source support for high-throughput JPEG 2000.
In addition to the decoding support for htj2k, openjpeg 2.5 also supports partial bitstream decoding. In terms of openjpeg encoder, v2 5 added support for TLM tag generation. Openjpeg version 2.5 also brings a series of bug fixes to improve itself.
Openjpeg 2.5.0 windows /Linux / MacOS binaries and source code can now be downloaded from GitHub: