These are chat archives for openseadragon/openseadragon

13th
Sep 2016
sickrandir
@sickrandir
Sep 13 2016 10:03

Hi @iangilman, long time no see, sorry.
If you remember I had a problem with my OSD based project: on Safari the DZI images disappeared at certain zoom level (the conversation was July the 20th).
You can see again the problem on Safari here: https://differenthood.duckdns.org/latest/#!/products/42
I list here the troubleshooting suggestions I tried:

  • smoothTileEdgesMinZoom: Infinity option -> no effect on the problem
  • normalize the image sizes and positions by multiplying or dividing by 1000, 5000 -> no effect on the problem
  • use plain images instead of DZI -> still not tried
  • generate a new set of DZI images with a tile_size of 508 and an overlap of 2 -> the images seemed to rendere with artifacts so I'm not sure they were perfectly generated but the problem was still visible.
  • generate a new set of DZI images with jpg tiles instead of transparent PNGs -> this seems to fix the problem but of course it's not a feasible solution. (don't have the example online at the moment but I can put it up in place of the original one with transparent PNGs).
    How can I help you further to troubleshoot the problem?

Thanx

Ignacio Tartavull
@tartavull
Sep 13 2016 12:25
Hi, I cannot figure out why tiles sometimes disappears when zooming or panning.
here is a demo of the problem I'm having https://tartavull.github.io/threedragons/
You can see when zooming in (using shift + mouse wheel) how some tiles are not displayed.
Do you think this might be related to the fact that I'm using 1024x1024 tiles?
with respect to #961 , here is a little snippet that prevents some of the flickering. try to using just mouse scroll in the demo above
John Hoffer
@thejohnhoffer
Sep 13 2016 15:20
@tartavull I've found a similar bug here at Issue #1029
Though, to be honest, our problems might be pretty different. Are you using multiple tileSources for the raw image data and for the segmentation overlay?
sickrandir
@sickrandir
Sep 13 2016 15:24
@thejohnhoffer that could be the same problem I'm experiencing. I used tiled images only and the transparency seems the key to trigger the problem.
John Hoffer
@thejohnhoffer
Sep 13 2016 15:24
Right- I've noticed that without transparency there is no problem in my tiled Images.
Have you tried switching back to OpenSeadragon 2.1.0 ?
sickrandir
@sickrandir
Sep 13 2016 15:25
no
John Hoffer
@thejohnhoffer
Sep 13 2016 15:25
That fixes my problems in Safari.
sickrandir
@sickrandir
Sep 13 2016 15:25
but I'll try it
John Hoffer
@thejohnhoffer
Sep 13 2016 15:25
Great!
sickrandir
@sickrandir
Sep 13 2016 15:26
actually I just checked and currently I'm using 2.2.0. With this version I can see the problem
I'll try with 2.1.0
sickrandir
@sickrandir
Sep 13 2016 15:37
@thejohnhoffer I just made a quick test and going back to 2.1.0 breaks the transparency of my images. They are just displayed with a white background. Maybe it could be related to some settings that I changed over the course of the project since I remember to have used 2.1.0 in the beginning without experiencing the same problem
John Hoffer
@thejohnhoffer
Sep 13 2016 15:38
Interesting... I haven't looked at your code long enough to see how you're doing transparaency.
But at any rate, do the tiles stop dissappearing at least?
sickrandir
@sickrandir
Sep 13 2016 15:39
i have DZI created from transparent PNGs and I add multiple images in the same viewer
one on top of the other
yes. they stop disappearing. Now if only I could restore transparency we will have a better test
I'll let you know
John Hoffer
@thejohnhoffer
Sep 13 2016 15:40
Ah, ok. openSeadragon has an API for setting transparency of an entire tileSource.
I'm working on a very similar problem, and I just use opaque jpgs and set the opacity within openSeadragon. Let me know once you find a way to get transparency working...
sickrandir
@sickrandir
Sep 13 2016 15:42
sure
Chris Engberg
@chris-engberg
Sep 13 2016 16:22
@tartavull totally not a solution, but if you set visibilityRatio back to 0.5 (not allow dragging more than 50% off the screen) that may solve youre issue temporarily. On my browsers, the tiles only dissapear when the center of the viewport is off the tileset.
sickrandir
@sickrandir
Sep 13 2016 16:49
@thejohnhoffer very interesting. I wasn't able to fix my current code to work with OSD 2.1.0 but I found some early code that was using the same transparent DZI images and its based on OSD 2.1.0. It seems that I'm not able to reproduce the problem
event with transparent images
I'll put it online asap
Ignacio Tartavull
@tartavull
Sep 13 2016 16:52
@thejohnhoffer I'm using the same tile for raw image and segmentation
John Hoffer
@thejohnhoffer
Sep 13 2016 16:53
@sickrandir Great! I've never encountered problems with OSD 2.1.0 even with transparency. If you switch that old working version to OSD 2.2.1, I bet you'll get problems again.
@tartavull Interesting- your problems do look a bit different from mine. I've never had problems on single layers, but we'll see once I try to implement z-stacks like you've done.
Ignacio Tartavull
@tartavull
Sep 13 2016 17:13
@chris-engberg I haven't had luck changing the visibilityRatiom the options just seems to be ignored. I'm btw using the very latest version from the master branched, because I needed the tile loaded event.
@thejohnhoffer yes, unless you find another way of implementing the stack. The implementation I wrote doesn't do any prefetching, and I've seen quite an slowdown when you have many tiledimages simultaneously. It seems that having some smooth transition between planes will take quite some development
Antoine Vandecreme
@avandecreme
Sep 13 2016 17:45
@sickrandir could you try changing tiledImage._isBottomItem() to always return false and see if the problem is still here?
That would mean there is a bug in openseadragon/openseadragon#861
it only happens in Safari correct? I don't have a mac so I won't be able to look into it but maybe you can figure it out by looking at the above PR?
John Hoffer
@thejohnhoffer
Sep 13 2016 17:55
I also noticed the bug in #1029 happens in Microsoft Edge
sickrandir
@sickrandir
Sep 13 2016 19:14
@avandecreme I made tiledImage._isBottomItem() return false and the problem seems even worse. Now even the "background" image disappear. Making the same function always return true instead breaks the transparency in the DZI images but they don't disappear anymore.
I can test only on Chrome, Safari and Firefox (No Microsoft Edge). Safari is the only one where it happens.