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IDProjectCategoryView StatusLast Update
0002952Slicer4Core: Usabilitypublic2014-04-29 10:01
ReporterfedorovAssigned Tojcfr 
Status acknowledgedResolutionopen 
Product Version 
Target VersionFixed in Version 
Summary0002952: Popup slider range in Volumes GUI is not initialized correctly

Sett attached screenshot. The range is 0 to 279 for the image, but the slider range is -1170 to 900.

TagsNo tags attached.


related to 0003452 assignedjcfr Unable to use Volume module Threshold widget in a meaningful way 


2013-02-14 12:44




2013-02-14 13:05

administrator   ~0007934

Reminder sent to: finetjul

Any idea what could be wrong here ? Thanks



2013-02-14 13:32

administrator   ~0007936

The slider with the range [-1170,900] is the slider that controls the range of the window level slider. There is 1 level of abstraction.

What values for such range would you suggest instead ?



2013-02-14 13:53

developer   ~0007937

Does it make sense to have the window/level range that exceeds the intensity range of the input?



2013-02-15 05:27

administrator   ~0007938

Yes if you want a ramp that is not pitch black for your lowest scalar value (or that is not bright white for your highest scalar value).



2013-02-15 06:50

developer   ~0007948

In my opinion, it's very confusing. If you want to control low/high color, why not just add the color popup selectors for the extremes? What is the meaning of the ranges [-1170, image_min] and [image_max,900]?

In any case, Ron thought this is a bug. I will forward this bug report to Ron, and if he is convinced by your argument, I have no problem is this issue is closed.



2013-02-15 07:05

administrator   ~0007950

Last edited: 2013-02-15 10:14

I agree with you, it is confusing, I(we) just didn't think of a better mechanism.
One thing to keep in mind, is that for a scalar range of [0, 279], it should be possible to have a window that ranges from [-100, 1000] because we want to associate 64 to the scalars 0, 66 to the scalars 1, ... and 128 to the scalars 279

255|                 ____________
...|                /|
128|           __... |
   |        __/      |
   |     __/  |      |
   |  __/|    |      |
  0| /   |    |      |
   -100  0    279... 1000


2013-02-15 11:45

developer   ~0007962

Ron told me he read the comments, and he does not understand your explanation. He says it should be [min,max] for the range.

I think we are thinking of the functionality of this slider in different ways, and your explanation does not come across.

I think what you are trying to say (if I understand you correctly) could be accomplished in a different (IMO, more intuitive) way. You could have one double-range slider for color map LUT (min=0, max=255). In your example above, it would be set to [66,128]. Then you would have a second double-range slider for the range of the image intensities (in our example, [0,279]), or a sub-range of the intensity range, if the original intensity range is very large -- this would be the initial value for the popup slider in question here . Then the second double-range slider would be the actual window/level for mapping image scalar values onto the LUT colors. min/max of this second double-slider would be initialized to the popup slider selected range.

If this is still confusing, why don't you just discuss this issue with Ron at the next opportunity.



2013-02-19 19:22

administrator   ~0007988

This seems like a valid solution, however I can see 2 drawbacks:

  • it requires to tweak 2 sliders instead of one (remember, the slider in the popup should rarely be used )
  • it is a different feel from the "window/level" radiologists are used to.

Maybe it's a better solution than the current one, I just wanted to raise those limitations.



2013-02-21 14:00

developer   ~0007998

Have you ever seen a radiologist using a slider to control w/l??? In my experience, "radiologist" and "slider" do not belong to the same sentence.

But jokes aside, I think the main issue is to make the interface intuitive and easy to understand. Reducing the number of controls is secondary. Maybe you can just ask around what other users think about the existing approach. I am confused as it is now. But I am not very smart, so it may be just me.



2013-02-22 09:58

administrator   ~0008002

@andriy: Which approach radiologist are currently using ? Couldn't e just inspire from this ?

Was the diagram reported below by Julien helpful to understand ? May we could refine the widget to propose a similar chart that could be interactive. Instead of having sliders ?



2013-02-24 03:34

developer   ~0008029

@jc: radiologists I work with use mouse to control w/l.

The primary customer for the functionality we are discussing is Ron. He is using it for some modes of volume rendering. So I think the best would be for Julien to discuss this with Ron to make sure he is happy with whatever changes are proposed (or if it is decided no changes are needed).

Issue History

Date Modified Username Field Change
2013-02-14 12:44 fedorov New Issue
2013-02-14 12:44 fedorov Status new => assigned
2013-02-14 12:44 fedorov Assigned To => kikinis
2013-02-14 12:44 fedorov File Added: Screen Shot 2013-02-14 at 17.42.16 .png
2013-02-14 12:44 fedorov Assigned To kikinis => jcfr
2013-02-14 13:04 jcfr Assigned To jcfr => sankhesh
2013-02-14 13:04 jcfr Target Version => Slicer 4.3.0
2013-02-14 13:05 jcfr Note Added: 0007934
2013-02-14 13:32 finetjul Note Added: 0007936
2013-02-14 13:32 finetjul Status assigned => feedback
2013-02-14 13:53 fedorov Note Added: 0007937
2013-02-15 05:27 finetjul Note Added: 0007938
2013-02-15 06:50 fedorov Note Added: 0007948
2013-02-15 07:05 finetjul Note Added: 0007950
2013-02-15 07:06 finetjul Note Edited: 0007950
2013-02-15 07:07 finetjul Note Edited: 0007950
2013-02-15 07:08 finetjul Note Edited: 0007950
2013-02-15 10:14 finetjul Note Edited: 0007950
2013-02-15 11:45 fedorov Note Added: 0007962
2013-02-19 19:22 finetjul Note Added: 0007988
2013-02-21 14:00 fedorov Note Added: 0007998
2013-02-22 09:58 jcfr Note Added: 0008002
2013-02-24 03:34 fedorov Note Added: 0008029
2013-06-03 05:15 jcfr Status feedback => assigned
2013-06-03 05:15 jcfr Assigned To sankhesh => jcfr
2013-09-02 20:19 jcfr Target Version Slicer 4.3.0 => Slicer 4.3.1
2013-10-01 11:49 jcfr Target Version Slicer 4.3.1 => Slicer 4.3.2
2013-10-18 09:33 finetjul Relationship added related to 0003452
2014-03-06 10:15 nicole Target Version Slicer 4.3.2 => Slicer 4.4.0
2014-04-29 10:01 jcfr Status assigned => acknowledged
2014-04-29 10:01 jcfr Target Version Slicer 4.4.0 =>