[gdal-dev] OpenJPEG

[Jukka Rahkonen]

Aaron Boxer <boxerab <at> gmail.com> writes:


> This feature would be quite involved: one would have to gather all of the
layers for 
> 
> all of the code blocks in all of the precincts overlapping that
sub-tile,plus the immediately surrounding precincts, run the inverse entropy
coder to get the wavelet coefficients, and then do an inverse wavelet
transform,with this incomplete set of coefficients.
> 

I do not claim that I understand GIS but I have a feeling that precincts are
designed for a fast ROI access. From
http://www2.engr.arizona.edu/~bilgin/publications/SPIE2004_2.pdf

"A precinct is a collection of code-blocks representing some finite spatial
extent at some resolution."

Probably gathering the surrounding precincts is unnecessary. Author of
Kakadu seems to dislike tiles and it is no wonder that with Kakadu precincts
perform well even with archived documents
http://www.digitizationguidelines.gov/still-image/documents/Martin.pdf.

-Jukka Rahkonen-