bugGNU Octave - Bugs: bug #41709, image-2.2.0 - bwdist giving wrong...

 
 

bug #41709: image-2.2.0 - bwdist giving wrong results on simple array

Submitted by:  None
Submitted on:  Wed 26 Feb 2014 03:01:52 PM UTC  
 
Category: Octave Forge PackageSeverity: 3 - Normal
Priority: 5 - NormalItem Group: Regression
Status: FixedAssigned to: Carnë Draug <carandraug>
Originator Name: BenoitOriginator Email: -unavailable-
Open/Closed: ClosedRelease: 3.8.0
Operating System: Any

Add a New Comment(Rich Markup)
   

You are not logged in

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

 

Sat 08 Mar 2014 01:51:16 AM UTC, comment #5:

For what is worth, I have just made the 2.2.1 release which has this bug fix.

Carnë Draug <carandraug>
Project MemberIn charge of this item.
Sat 08 Mar 2014 01:00:58 AM UTC, comment #4:

I have fixed this with changeset 875:9a76652a01f5

The problem happened when the code originally had variable "h" for width and "w" for height. Note that they are swapped. I can only guess why but probably because the code was originally written for row-major order
and it would be easier to swap the assignment to these two variables than all instances of it in the code.

It should be fixed, and I added this case to the test suite of the image package.

This fix will be released with the next stable release, version 2.2.1 which should be soon.

Carnë Draug <carandraug>
Project MemberIn charge of this item.
Fri 07 Mar 2014 06:16:08 PM UTC, comment #3:

I gave it a quick look and it seems that this bug only presents for elements on the top and bottom row. The distance calculation is correct, it's the x and y dist that appear to be swapped.

Carnë Draug <carandraug>
Project MemberIn charge of this item.
Wed 26 Feb 2014 10:19:25 PM UTC, comment #2:

You are right, that's a regression. If you can provide a patch for this, it's very welcome but at the moment I'm unable to do so.

Carnë Draug <carandraug>
Project MemberIn charge of this item.
Wed 26 Feb 2014 03:08:02 PM UTC, comment #1:

and the remaining of the original post...

Result for C is:

Octave 3.8.0 - Image 2.2.0
C =
1 5 9 13 16 21 25 29 33
2 6 10 14 13 22 26 30 34
3 7 10 15 19 23 27 31 35
5 8 12 16 20 24 28 32 36

Note that the value in row 1 col 4 is 5. This is incorrect, it should be either 3 or 8! Same in row 5 cols 1 and 2.

In image-2.0.0, a more sensible value for C is produced:

Octave 3.8.0 - Image 2.0.0
C =
1 5 9 13 13 21 25 29 33
2 6 10 14 14 22 26 30 34
3 7 10 15 19 23 27 31 35
8 8 12 16 20 24 28 32 36

Comments?

Regards,
Benoit

Anonymous
Wed 26 Feb 2014 03:01:52 PM UTC, original submission:

The example below demonstrates that the linear index (C) is not correct (as in [D,C] = bwdist(BW, METHOD)):

Result for C is:

Anonymous

 

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

Attach File(s):
   
   
Comment:
   

No files currently attached

 

Depends on the following items: None found

Items that depend on this one: None found

 

CC list is empty

 

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 4 latest changes.

Date Changed By Updated Field Previous Value => Replaced By
Sat 08 Mar 2014 01:00:58 AM UTCcarandraugStatusNone=>Fixed
  Assigned toNone=>carandraug
  Open/ClosedOpen=>Closed
Wed 26 Feb 2014 10:19:25 PM UTCcarandraugOperating SystemMicrosoft Windows=>Any

Back to the top


Powered by Savane 3.1-cleanup1