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ruven / iipsrv

iipsrv is an advanced high-performance feature-rich image server for web-based streamed viewing and zooming of ultra high-resolution images.
https://iipimage.sourceforge.io
GNU General Public License v3.0
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FLIF image support #96

Open benepo opened 7 years ago

benepo commented 7 years ago

Feature request: support FLIF images (superior lossless compression compared to JPEG2000)

Possibly related: https://github.com/FLIF-hub/FLIF/issues/12 so @jonsneyers may have some ideas for how to handle gigapixel sized astronomy images...

ahankinson commented 7 years ago

FLIF doesn't yet support tiles. Is that a problem?

benepo commented 7 years ago

For the current JPEG 2000 support, does iipsrv dynamically transcode and slice single gigapixel JPEG 2000 images into small browser-friendly image tiles (i.e. jpg or png)? I'm hoping some technical SMEs can weigh in and provide a rough level of effort estimate that would be required to accomplish FLIF integration.

benepo commented 7 years ago

Also, it may be helpful to compare the TIFF support from VisiOmatic (an older fork of iipsrv):

ruven commented 7 years ago

For the current JPEG2000 implementation, iipsrv does indeed slice up the image into tiles, but this slicing is very efficient due to the existence of precincts and progressive resolution encoding within JPEG2000. With TIFF of course, the tiling and multi-resolution is explicitly encoded in the TIFF structure.

FLIF looks interesting, but the lack of native tiling and lack of multi-resolution support will make it very slow for large images. So, yes it could be integrated (as could formats such as WebP), but it risks to be disappointingly slow.

Regarding VisiOmatic, the vast majority of the forked code (apart from, for the moment, TIFF pointer caching) has been rolled into the main iipsrv code and iipsrv now fully supports floating point data as well as terabyte scale images as of version 1.0: http://iipimage.sourceforge.net/2015/03/web-based-visualization-of-very-large-scientific-astronomy-imagery/