Warning, it's very work in progress, won't handle incbin files, uses the file "temp.bmp" as an intermediate so only 3 channel (no alpha) jpeg 2000 files are supported. Once the decoding is streamed directly to pixmap will have alpha channel support and I would also expect some improvement in speed also.
I would use it for non-critical testing right now :)
BTW, fab work skid, nice one!