2000.03.30 13:18 "Re: jpeg2000 question", by Andy

Hello,

I have wondered about this also. I have not seen any specific JPEG2000 sample files. I believe JPEG and SPIFF data stream are legitimate JPEG2000 data streams.

The large portion of change is due to wavelet encoding. I hear for this to look into EBCOT, or perhaps it is EZW, and something about lifting trees or something, IWT and DWT. The other thing to keep in mind is lossless JPEG-LS (HP LOCO). I might be wrong, but I heard somewhere that the JPEG2000 IP owners allow use of the methods in a JPEG2000 compliant implementation gratis.

In terms of TIFF, we might ask Senor Lane to guide us in describing TIFF profile. It would take a compression number, we can use a high unassigned one until... oh, yeah, until Adobe gets off their TIFF, as if, then we could figure out what the tags were and assign those to unassigned tags, then we might community develop extensions to libjpeg as feasible to integrate JPEG2000 codec into libtiff.

I see there is a recent spec. from the www.jpeg.org people about JPEG2000 standard document. It's pretty big.

About TIFF again, I am thinking JPEG supports large image rasters somehow, we could figure out how that could work with planned 64 bit file offsets and tile handling, or something.

So, in terms of TIFF, it would be necessary to determine tags external to data stream for coder, and then required algorithms, and then the math, egad, for ANSI C. So, the result would be public domain JPEG2000 coder and recommended practice for JPEG2000 embedding in TIFF.

It would be a good thing to see. Pleasant day to you,

Andy