2002.10.03 14:05 "Re: JPEG 2000 in TIFF", by Frank Warmerdam

I'm interested about JPEG 2000 in TIFF.

Is an integration of this compression as a new codec in libtiff is planned? At the matter of fact it's only the writting of an interface file tif_jp2.c file as the tif_jpeg.c file for standard jpeg...

Julien,

I have been thinking about the idea of embedding jpc (jpeg 2000 code streams) as TIFF tiles or strips. The idea would be that each chunk of strip or tile data would be a free standing JPEG 2000 data stream in "jpc" format. That is they would not have the extra .jp2 wrapper info but there would still potentially be a fair amount of information duplication between the jpc streams.

Various libraries, such as JasPer, should be able to provide the JPEG2000 jpc read/write support.

If we take this approach we would need to assign a new compression code, and implement a tif_jpc_jasper.c or something like that.

Note that the JasPer license states:

"F. This software is for use only in hardware or software products that are compliant with ISO/IEC 15444-1 (i.e., JPEG-2000 Part 1). No license or right to this Software is granted for products that do not comply with ISO/IEC 15444-1. The JPEG-2000 Part 1 standard can be purchased from the ISO."

The standalone .jpc format is a format defined in the aformentioned ISO specification. However, it isn't clear to me whether jpc format embedded within TIFF would be considered a product complying with ISO/IEC 15444-1 or not.

Also, even if we didn't limit ourselves to use of JasPer, I am concerned that the various agreements by patent holders for aspects of the JPEG2000 specification only apply to ISO/IEC 15444-1 products. That is to say, various organizations involved in the JPEG-2000 specification process have given permission for their patented approaches to be use in JPEG-2000 without royalties; however, those grants might not be considered to apply to JPEG2000 in TIFF.

However, I for one would be willing to take the chance, at least for prototyping purposes.

Best regards,

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