Feature detection code in MATLAB

Hello Everyone
I am having an image of dimension 512*512 in square shape.I want to select corner point of this image as feature point. anyone could help me to write the code for this feature extraction process using MATLAB.

Thanks

 0
11/24/2010 6:05:52 AM
comp.soft-sys.matlab 207508 articles. 4 followers. lunamoonmoon (258) is leader.

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On Nov 24, 6:05=A0am, amit <amiteshkuma...@gmail.com> wrote:
> Hello Everyone
> =A0I am having an image of dimension 512*512 in square shape.I want to se=
lect corner point of this image as feature point. anyone could help me to w=
rite the code for this feature extraction process using MATLAB.
>
> =A0 Thanks

--------------------------
Upgrade to R2010b and get the new cornermetric function built in to
the Image Processing Toolbox:

cornermetric

Create corner metric matrix from image
Description

c =3D cornermetric(I) generates a corner metric matrix for the grayscale
or logical image I. The corner metric, c, is used to detect corner
features in I and is the same size as I. Larger values in c correspond
to pixels in I with a higher likelihood of being a corner feature.

c =3D cornermetric(I, method) generates a corner metric matrix for the
grayscale or logical image I using the specified method. Valid values
for method are:
Value	Description
'Harris'	The Harris corner detector. This is the default method.
'MinimumEigenvalue'	Shi and Tomasi's minimum eigenvalue method.


 0
ImageAnalyst
11/24/2010 2:26:42 PM
ImageAnalyst <imageanalyst@mailinator.com> wrote in message <ccb270d6-009c-4bac-99db-a7c5ecbe5f39@s4g2000yql.googlegroups.com>...
> On Nov 24, 6:05 am, amit <amiteshkuma...@gmail.com> wrote:
> > Hello Everyone
> >  I am having an image of dimension 512*512 in square shape.I want to select corner point of this image as feature point. anyone could help me to write the code for this feature extraction process using MATLAB.
> >
> >   Thanks
>
> --------------------------
> Upgrade to R2010b and get the new cornermetric function built in to
> the Image Processing Toolbox:
>
> cornermetric
>
> Create corner metric matrix from image
> Description
>
> c = cornermetric(I) generates a corner metric matrix for the grayscale
> or logical image I. The corner metric, c, is used to detect corner
> features in I and is the same size as I. Larger values in c correspond
> to pixels in I with a higher likelihood of being a corner feature.
>
> c = cornermetric(I, method) generates a corner metric matrix for the
> grayscale or logical image I using the specified method. Valid values
> for method are:
> Value	Description
> 'Harris'	The Harris corner detector. This is the default method.
> 'MinimumEigenvalue'	Shi and Tomasi's minimum eigenvalue method.

thanx a lot ImageAnalyst..
If possible provide me the  matlab code for Harris  Corner Detector method...it will be great help for me ...

 0
amitesh
11/24/2010 2:43:03 PM
The best place to look first is always the File Exchange:

http://www.mathworks.com/matlabcentral/fileexchange/9272-harris-corner-detector

 0
Image
11/24/2010 2:56:04 PM
"Image Analyst" <imageanalyst@mailinator.com> wrote in message <icj923$rsb$1@fred.mathworks.com>...
> The best place to look first is always the File Exchange:
>
> http://www.mathworks.com/matlabcentral/fileexchange/9272-harris-corner-detector

hello Image Analyst
i downloaded this file from file exchange. when i am running this Harris. m file , i get a image . but when  i move the mouse on the excuted image and click as par given instruction  ,than i got the following message on the command window --

Warning: Image is too big to fit on screen; displaying at 67%
> In imuitools\private\initSize at 73
In imshow at 264
In Harris at 7

PIP =

Empty matrix: 0-by-2

Warning: Image is too big to fit on screen; displaying at 67%
> In imuitools\private\initSize at 73
In imshow at 264
In Harris at 80

What should i do to get the feature point succesfully.plz suggest me .....

 0
amitesh
11/26/2010 10:59:05 AM
On Nov 26, 5:59=A0am, "amitesh kumar" <amiteshkuma...@gmail.com> wrote:
> hello Image Analyst
> What should i do to get the feature point succesfully.plz suggest me ....=
..
-----------------------------
amitesh kumar:
You should try to contact the author, but since he probably won't
answer, you should try to debug it yourself.  I have no idea what the
internal code of that File Exchange submission is doing, but I think
you could debug it as well as I could.  Secondly I would upgrade to
the newest MATLAB and try to run the built-in corner detection
function.  These are the things I would do if it were me that had to
get this working.
Good luck,
ImageAnalyst


 0
ImageAnalyst
11/26/2010 2:00:14 PM
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