These are chat archives for openseadragon/openseadragon

13th
Oct 2015
Justin MacCarthy
@macarthy
Oct 13 2015 09:01
var viewer = OpenSeadragon({
id: 'viewer',
constrainDuringPan: true,
visibilityRatio: 1,
prefixUrl: "/viewer/",
minZoomLevel: 1,
maxZoomPixelRatio: 1.6,
tileSources: TILE_SOURCES,
gestureSettingsMouse: {
scrollToZoom: false
}
});
I'm using openseadrgaon 1.1.* with above settings, and i tried to upgrade to v2. the loading of tiles got really realy slow (TILE_SOURCES is an array of dzi)
What i need to do to upgrade?
Justin MacCarthy
@macarthy
Oct 13 2015 09:44
Was there a big change in the way tiles are loaded?
Antoine Vandecreme
@avandecreme
Oct 13 2015 15:48
@macarthy , did you set sequenceMode to true?
Ian Gilman
@iangilman
Oct 13 2015 16:21
Yup, that's probably it.
David Rogers
@dwrogers
Oct 13 2015 16:26
Bird's-eye view... Does OSD support this? Has anyone else come across the request? The use case is examining a slide, with the foreground at maximum magnification (bottom of screen), and the background dropping off to a lower magnification (top of screen). Now imagine aligning the tissue boundary parallel to the bottom of the screen, and panning horizontally along the tissue boundary. You can see the most interesting parts at max mag, but you also can simultaneously see 300 - 500 % more of the slide in the field of view at once, allowing you to catch anomalies just off the tissue boundary.
Ian Gilman
@iangilman
Oct 13 2015 16:28
@dwrogers Sounds similar to the OSD navigator, but more like a split screen than a picture-in-picture?
David Rogers
@dwrogers
Oct 13 2015 16:30
@iangilman I'll look again at the OSD navigator... But rather than a split screen, a smooth transition from the foreground to the background. A thumbnail with a field-of-view highlight would show the active field-of-view as a trapezoid rather than a square.)
Ian Gilman
@iangilman
Oct 13 2015 16:34
Interesting...we don't have support for non-rectangular viewers; not sure what would be the best approach there.
At any rate the navigator might work (you can position and resize it), but maybe not, since you probably want both viewers to be somewhat zoomed out (where as the navigator is always fully zoomed out).
Probably your best bet is to make two viewers and have the "field of view" viewer listen to the "overview" viewer for pan events and sync to them.
That sort of thing is pretty straight forward
VoidVolker
@VoidVolker
Oct 13 2015 16:38
I think it can be done next way: create hidden canvas, render there max zoom, on main canvas don't render few items in center (which fully in circle), and after main canvas render stage, render in circle zoomed canvas
it will be loupe
to make trully bird-eye view need make more render layers on circle edge
to get smooth transition
Lucian
@dyablohunter
Oct 13 2015 18:46
Hi there :)
Ian Gilman
@iangilman
Oct 13 2015 18:47
Hello!
Lucian
@dyablohunter
Oct 13 2015 18:53
So I have a few questions.
Ian Gilman
@iangilman
Oct 13 2015 18:54
Is this Lucian?
Lucian
@dyablohunter
Oct 13 2015 18:54
yes :)
you got me!
David Rogers
@dwrogers
Oct 13 2015 20:40
@VoidVolker @iangilman Here are a couple of pictures demonstrating the feature in a commercial viewer:
Normal
Birdseye
Ian Gilman
@iangilman
Oct 13 2015 20:42
@dwrogers The image didn't come through for me
VoidVolker
@VoidVolker
Oct 13 2015 20:48
same thing
use some picture hosting
David Rogers
@dwrogers
Oct 13 2015 21:10
This message was deleted
This message was deleted
Let's try a link: Normal-vs-Birdseye
Ian Gilman
@iangilman
Oct 13 2015 21:18
@dwrogers I see...so you're actually distorting the image. There's no support for that in OSD. You might be able to create an offscreen viewer, and copy out of its canvas and do the distortion that way. Unfortunately, since the viewer wouldn't be aware of what you were doing, it would load a lot more detailed imagery than you actually needed.
It's a cool scenario, though!
To support it directly, I guess we would need to make the image renderer aware of rotation in 3D space, so it knew not to get high res tiles for the area that was going to be scaled down
David Rogers
@dwrogers
Oct 13 2015 21:59

@VoidVolker @iangilman

So, it sounds like the closest I could come for now would be by doing it bifocal-style: essentially having two viewers and keeping them both in sync with each other by forwarding events. I could have a band across the bottom which would be the view at the higher resolution, and the rest of the screen would be at a lower resolution.

You could think of this (or implement it) as an inverse navigator.

It does seem like birds-eye view might be generally useful, for any image processing where one is hunting for specific features, since it would allow you to scan an image much more rapidly. The gradual drop-off in magnification creates an extremely intuitive experience.

Ian Gilman
@iangilman
Oct 13 2015 22:16
@dwrogers Indeed, bifocal is definitely doable now. The birds eye would be a lot more work. Would be neat, though!