bugGNU Octave - Bugs: bug #46872, imread not loading certain indexed...

 
 

bug #46872: imread not loading certain indexed png correctly

Submitted by:  Hari <kkharinarayanan>
Submitted on:  Mon 11 Jan 2016 05:48:22 AM UTC  
 
Category: Octave FunctionSeverity: 3 - Normal
Priority: 5 - NormalItem Group: Incorrect Result
Status: ConfirmedAssigned to: None
Originator Name: HarinarayananOpen/Closed: Open
Release: 4.0.0Operating System: GNU/Linux

Add a New Comment(Rich Markup)
   

You are not logged in

Please log in, so followups can be emailed to you.

 

Mon 22 Feb 2016 05:50:11 PM UTC, comment #4:

Just ran across bug #41584, this may be describing the same symptom as that one.

Mike Miller <mtmiller>
Project Administrator
Mon 22 Feb 2016 05:43:45 PM UTC, comment #3:

Same here, and I can confirm that I can use "gm convert" to reformat the provided image to a full-color image file, and then imread loads it accurately.

Here is the output of "gm identify -verbose"

Mike Miller <mtmiller>
Project Administrator
Tue 16 Feb 2016 02:22:15 AM UTC, comment #2:

I can confirm that loading that figure with imread (in the prehistoric version of Octave I have at work) gives a matrix with only 0s and 1s. I'm using fltk, but it is a reading problem, not a plotting problem.

For reference, Matlab correctly distinguishes values 0, 1, 2 and 3 in that image.

Lachlan Andrew <lachlan>
Project Member
Wed 13 Jan 2016 02:34:30 AM UTC, comment #1:

Looks like in the problem case that the color range might be too small so that both the dark blue and light blue are mapped to the maximum range value. What graphics toolkit are you using? E.g.,

octave:1> graphics_toolkit
ans = gnuplot

What commands to load?

Dan Sebald <sebald>
Mon 11 Jan 2016 05:48:22 AM UTC, original submission:

upon loading the problem_image_original.png, the array has only two unique values as seen in problem_image_loaded.png.

The other two images are just for reference of an image which loads without any problems.

Please see attachments

Hari <kkharinarayanan>

 

(Note: upload size limit is set to 16384 kB, after insertion of the required escape characters.)

Attach File(s):
   
   
Comment:
   

 

Depends on the following items: None found

Items that depend on this one: None found

 

Carbon-Copy List
  • -unavailable- added by mtmiller (Posted a comment)
  • -unavailable- added by lachlan (Posted a comment)
  • -unavailable- added by sebald (Posted a comment)
  • -unavailable- added by kkharinarayanan (Submitted the item)
  •  

    Do you think this task is very important?
    If so, you can click here to add your encouragement to it.
    This task has 0 encouragements so far.

    Only project members can vote.

     

    Please enter the title of George Orwell's famous dystopian book (it's a date):

     

     

    Follow 6 latest changes.

    Date Changed By Updated Field Previous Value => Replaced By
    Mon 22 Feb 2016 05:43:45 PM UTCmtmillerSummaryIncorrect loading of images=>imread not loading certain indexed png correctly
    Tue 16 Feb 2016 02:22:15 AM UTClachlanStatusNone=>Confirmed
    Mon 11 Jan 2016 05:48:22 AM UTCkkharinarayananAttached File-=>Added problem_image_original.png, #35980
      Attached File-=>Added no_problem_image_original.png, #35981
      Attached File-=>Added problem_image_loaded.png, #35982
      Attached File-=>Added no_problem_image_loaded.png, #35983

    Back to the top


    Powered by Savane 3.1-cleanup1