Bruno P. Kinoshita commented on IMAGING-161:

Started working on this issue, first by reading a bit about ITU-T T.4 and T.6 
compression algorithms.
 * [https://www.itu.int/rec/T-REC-T.4/en]
 * [https://www.itu.int/rec/T-REC-T.6/en]
 * [https://en.wikipedia.org/wiki/Group_4_compression]
 * [http://fileformats.archiveteam.org/wiki/JPM]
 * [https://en.wikipedia.org/wiki/JPEG_2000]
 * [http://www.loc.gov/preservation/digital/formats/fdd/fdd000144.shtml]

>From the Wikipedia article, it appears the "Group 4 compression is available 
>in many proprietary image file formats as well as standardized formats such as 
>TIFF, CALS, CIT (Intergraph Raster Type 24) and the PDF document format".

But JPEG2000 (or at least JPM) also appears to support/use the modified Huffman 
(ITU T.4). So it could be that in the future we decide to go back and make it a 
common package, shared by other formats. At least I'd like to have JPEG2000 as 
it's quite common in scientific imagery, and also in IIIF.

I am removing it from V 1.0, so that we can further discuss and decide what to 
do about it later, hope it makes sense [~britter] & others.



> Move package commons.itu_t4 to formats.tiff package
> ---------------------------------------------------
>                 Key: IMAGING-161
>                 URL: https://issues.apache.org/jira/browse/IMAGING-161
>             Project: Commons Imaging
>          Issue Type: Improvement
>          Components: Format: TIFF, imaging.common.*
>            Reporter: Benedikt Ritter
>            Assignee: Benedikt Ritter
>            Priority: Major
>             Fix For: Review Patch
> All public methods from the T4AndT6Compression class are only used in the 
> tiff package. We should move the code to the tiff package and make it package 
> private to remove it from the public API.

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