[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Octave-bug-tracker] [bug #46547] image package: canny detector in edge(
From: |
Hartmut |
Subject: |
[Octave-bug-tracker] [bug #46547] image package: canny detector in edge() should use LoG as first step |
Date: |
Thu, 26 Nov 2015 19:29:22 +0000 |
User-agent: |
Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:42.0) Gecko/20100101 Firefox/42.0 |
URL:
<http://savannah.gnu.org/bugs/?46547>
Summary: image package: canny detector in edge() should use
LoG as first step
Project: GNU Octave
Submitted by: hardy
Submitted on: Do 26 Nov 2015 19:29:21 GMT
Category: Octave Forge Package
Severity: 3 - Normal
Priority: 5 - Normal
Item Group: Matlab Compatibility
Status: None
Assigned to: None
Originator Name:
Originator Email:
Open/Closed: Open
Discussion Lock: Any
Release: 4.0.0
Operating System: Any
_______________________________________________________
Details:
I moved this away from bug report #46099 (comment 2 of an anonymous use),
because it is a different and new topic. The following is a quote:
=========================================
I'm evaluating an image binarization code (originaly developed for Matlab)
with Octave (4.0.0) and image package (2.4.1). After some investigation on why
I'm getting worse results with Octave than with Matlab (R2012b), I've found
that edge function with 'Canny' method outputs a much noisier result with
Octave than with Matlab. In order to give an example, I've run the following
code with both software:
clear, close all;
I = imread('sample2.png');
thresholds = [5.2742e-004 0.3899];
BW = edge(I, 'Canny', thresholds);
imwrite(BW, 'result_edge_canny_sample2.png');
As one can see in the attached files, "Octave_result_edge_canny_sample2.png"
is much noisier than "ML2012b_result_edge_canny_sample2.png". As a result, the
binarized image (generated by the image binarization code, which uses edge
function with 'Canny' method) is also noisy and almost useless.
_______________________________________________________
File Attachments:
-------------------------------------------------------
Date: Do 26 Nov 2015 19:29:21 GMT Name: sample2.png Size: 24kB By: hardy
<http://savannah.gnu.org/bugs/download.php?file_id=35565>
-------------------------------------------------------
Date: Do 26 Nov 2015 19:29:21 GMT Name: Octave_result_edge_canny_sample2.png
Size: 3kB By: hardy
<http://savannah.gnu.org/bugs/download.php?file_id=35566>
-------------------------------------------------------
Date: Do 26 Nov 2015 19:29:21 GMT Name: ML2012b_result_edge_canny_sample2.png
Size: 823B By: hardy
<http://savannah.gnu.org/bugs/download.php?file_id=35567>
_______________________________________________________
Reply to this item at:
<http://savannah.gnu.org/bugs/?46547>
_______________________________________________
Nachricht gesendet von/durch Savannah
http://savannah.gnu.org/
- [Octave-bug-tracker] [bug #46547] image package: canny detector in edge() should use LoG as first step,
Hartmut <=