These are chat archives for openseadragon/openseadragon

13th
Jun 2016
Seb2A
@Seb2A
Jun 13 2016 13:56
Hello Ian, we've just started with openseadragon and I want to say woaoh. For my poor devlopper experience (and my poor english...) I think OSD is so sexy for HD image rendering. We are now trying to render a 360° rotative image via a sequence of 3D HD tiled image. We are observing some flickering effect on fast image transition. Is there some option or parameter to correct this?
Erik Sjölund
@eriksjolund
Jun 13 2016 19:58

I am developing an MIT-licensed web tool on top of OpenSeadragon.
Unfortunately there are no photos to show right now,but the web tool already seems to work. I implemented an idea I
had: Storing all the photo tiles in a single
data file together with some scientific measurement data. The photo
is a cell tissue and the measurement data represents
gene expression measurement points. By having the data in a single
file structured with a header containing an index
of the content, it is possible to open the data file both as a local
file through the "File API" and as a remote file over XMLHttpRequest.

Note that there is no need to read/download the whole data to look at it. When different image tiles are needed they are read/downloaded as byte ranges from the data file. This works because the "File API" supports reading byte ranges out of local files, and web servers normally seem to support the HTTP RANGE header.

For painting the measurement points I tried a few approaches:
https://github.com/eriksjolund/osd-spot-viewer

Some more links:
http://eriksjolund.github.io/osd-spot-viewer/from_layout/index.html
https://github.com/eriksjolund/osd-spot-viewer/blob/master/from_layout/src/entry.js
openseadragon/openseadragon#944

VoidVolker
@VoidVolker
Jun 13 2016 20:07
and why need this format?
what for?
Ian Gilman
@iangilman
Jun 13 2016 22:56
@VoidVolker There's discussion in #944
@Seb2A Glad you like! We have nothing directly for that, but it's a frequent enough question that I guess we should put something together. At any rate, you need to load the multiple images into the same OSD "world" and allow them to load their tiles so that they are already ready by the time you switch to them.
Ian Gilman
@iangilman
Jun 13 2016 23:09
@Seb2A @tartavull I've started an issue to further discuss this stuff: openseadragon/openseadragon#961