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Ticket #1096 (closed defect: fixed)

Opened 2012-04-10T13:48:11-05:00

Last modified 2012-08-29T13:48:48-05:00

SaltAndPepper issue

Reported by: bdezonia Owned by: bdezonia
Priority: major Milestone: imagej2-b4-plugins
Component: Plugins Version:
Severity: serious Keywords:
Cc: Blocked By:
Blocking: #1333


The SaltAndPepper plugin fills in pixels with min/max values relative to the type (0/255 for 8-bit, 0/65535 for 16-bit, etc.). This can cause problems.

To see a problem try the following:
open T1 Head
run SaltAndPepper
run Noise Reducer plugin
in the plugin use median and 3x3 neighborhood

notice after running that everything looks black. But if you move z slider to middle and look at probe you can see there are many nonzero pixel values. Unfortunately there are som 0's and some 65535's and everything else is on a scale that is not visible.

We need to determine better values for filling salt and pepper pixels in images that are not 8-bit

Change History

comment:1 Changed 2012-05-04T11:14:03-05:00 by bdezonia

Alternatively smart display range handling could improve situation

comment:2 Changed 2012-05-14T11:14:18-05:00 by bdezonia

  • Milestone changed from imagej-2.0.0-beta3 to imagej-2.0.0-beta4

comment:3 Changed 2012-07-02T14:27:48-05:00 by bdezonia


  • add parameters for Salt value and Pepper value
  • default them to persisted values (initially 0,255)
  • provide an Auto button that uses the current image's min/max pixel values

comment:4 Changed 2012-07-17T16:23:52-05:00 by bdezonia

  • Blocking 1333 added

The application of S&P to images other than 8=bit is functionality beyond IJ1. Proceed with plan.

comment:5 Changed 2012-08-27T16:14:52-05:00 by bdezonia

With commit d1d0fc8963c11fb0fd14d69f21a702715b8387d6 the specification of salt/pepper values in place.

Now just need auto button or checkbox that specifies to use image min/max values

comment:6 Changed 2012-08-29T13:48:48-05:00 by bdezonia

  • Status changed from new to closed
  • Resolution set to fixed

With commit 9371d6d49db8c81bcde91c9bfc233ba2a551b5b3 the user can choose a checkbox that will allow the max and min data values to be used as the salt and pepper values.

We could have a nice button that when clicked would compute those values and update the dialog before you hit OK. But that may be overkill and likely waits upon some needed infrastructure. Closing this and opening a new ticket for that functionality in a later milestone.