Ticket #1577 (assigned defect)

Opened 7 years ago

Last modified 5 years ago

Screen output non-linear

Reported by: aivar Owned by: curtis
Priority: major Milestone: imagej2-b8-analysis
Component: Display API Version:
Severity: serious Keywords:
Cc: Blocked By:
Blocking: #1244

Description

Load clown.jpg and examine pixel (84, 32) with the DigitalColor Meter utility on OS X.

Actual value of pixel and Probe Tool value is (221, 204, 186). Displayed value is (245, 226, 209).

Change History

comment:1 Changed 7 years ago by aivar

  • Blocking 1244 added

comment:2 Changed 7 years ago by aivar

  • Owner changed from curtis to aivar
  • Status changed from new to assigned

Reassigned to myself, aivar, as this pertains to binning problems when converting a color component value to a LUT bin.

comment:3 Changed 7 years ago by aivar

Printed out some debugging information in net.imglib2.display.AbstractColorTable.lookupARGB():

RED min 0.0 max 255.0 value 241.0 bin 241
GREEN min 0.0 max 255.0 value 160.0 bin 160
BLUE min 0.0 max 234.0 value 42.0 bin 45
RED min 0.0 max 255.0 value 249.0 bin 249
GREEN min 0.0 max 255.0 value 168.0 bin 168
BLUE min 0.0 max 234.0 value 50.0 bin 54
. . .

Did Color/Split Channels and analyzed R, G, B images with IJ2 Histogram Plot (IJ1 Histogram ignores the split channels and deals only with the original!). Indeed the max value for R and G is 255 and for the B component its 234.

This debugging printout shows R & G are correctly linear; B is being autoscaled to the 0..234 range by default, which I believe is an inappropriate distortion. However this does not explain the issue of this ticket: I'm observing all components are too light, not just B.

Version 0, edited 7 years ago by aivar (next)

comment:4 Changed 7 years ago by aivar

Added debugging info in AbstractColorTable.argb():

RED min 0.0 max 255.0 value 241.0 bin 241
argb bin is 241 r 241 g 0 b 0
GREEN min 0.0 max 255.0 value 160.0 bin 160
argb bin is 160 r 0 g 160 b 0
BLUE min 0.0 max 234.0 value 42.0 bin 45
argb bin is 45 r 0 g 0 b 45
RED min 0.0 max 255.0 value 249.0 bin 249
argb bin is 249 r 249 g 0 b 0
GREEN min 0.0 max 255.0 value 168.0 bin 168
argb bin is 168 r 0 g 168 b 0
BLUE min 0.0 max 234.0 value 50.0 bin 54
argb bin is 54 r 0 g 0 b 54
RED min 0.0 max 255.0 value 253.0 bin 253
argb bin is 253 r 253 g 0 b 0
GREEN min 0.0 max 255.0 value 173.0 bin 173
argb bin is 173 r 0 g 173 b 0
BLUE min 0.0 max 234.0 value 52.0 bin 56
argb bin is 56 r 0 g 0 b 56
RED min 0.0 max 255.0 value 249.0 bin 249
argb bin is 249 r 249 g 0 b 0
GREEN min 0.0 max 255.0 value 169.0 bin 169

The R, G, B ramp palettes look good: a red bin of 249 translates to a color (249, 0, 0) as it should.

comment:5 Changed 6 years ago by bdezonia

  • Milestone changed from imagej2-b7-ndim-data to imagej2-b8-analysis

comment:6 Changed 5 years ago by curtis

  • Owner changed from aivar to curtis
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