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From: Avengeline on 12 Mar 2010 05:14
ImageAnalyst <imageanalyst(a)mailinator.com> wrote in message <87b76e9b-a30a-4b52-a3e4-2924dac10e8d(a)e7g2000yqf.googlegroups.com>...
> On Mar 11, 8:54 am, "Avengeline " <avengeline....(a)gmail.com> wrote:
> > BW = edge(Y,'sobel',[], 'vertical');
> > B1 = bwmorph(BW,'skel',Inf);
> >
> > ...but still no difference. Any other suggestion?
> -----------------------------------------------------------------------------------------
> Yes - that's not surprising.
>
> Apparently you didn't read or understand what I said about the built-
> in edge() function automatically thresholding and skeletonizing the
> gray scale edge image. So it makes sense (now that you know this)
> that skeletonizing an already skeletonized image will make no
> difference.
>
> I'm not sure what you want to do. Do you want thin edges or thick
> edges?
>
> If you want the original, un-processed edge image, you should look up
> fspecial() and imfilter().
>
> And like Ashish recommended, posting an image somewhere (like http://drop.io)
> might help in this conversation.

I guess I dont have a deeper understanding on the edge() function..

Anyway,.. in your point of view...

from this graph... http://farm5.static.flickr.com/4068/4426963732_90f9fd0658_o.jpg

I know it is possible to have an edge like E2..

How about for E1 and E3?

The y-axis is the gray value.. x-axis is the column position of the image..
this graph is plotted based on one row of image... but till column 15..
From: ImageAnalyst on 12 Mar 2010 06:49
I suppose. Why don't you post an image and see what we can do with
that?
From: Avengeline on 12 Mar 2010 07:41
ImageAnalyst <imageanalyst(a)mailinator.com> wrote in message <d3f578b7-f1b7-4b37-981e-03cbd706b772(a)f8g2000yqn.googlegroups.com>...
> I suppose. Why don't you post an image and see what we can do with
> that?


this is the image: http://drop.io/gyx0i87/asset/img150-bmp

basically, i convert the image to ycbcr.. take y component image..
did sobel edge detection (default threshold) on the y component image..
then...
at row 4, col 767.. an edge is detected..

here is the graph: http://farm3.static.flickr.com/2524/4426368251_9723da179f_o.jpg

yaxis-luminance value..
x-axis-column position from 760 to 768..

if such case happen.. may i know what is the local minima and local maxima for that edge position...

the local maxima is the same as the edge position?
From: ImageAnalyst on 12 Mar 2010 08:08
There are so many edges in this image that it's basically a judgement
call. There are lots of algorithms that would give different edges on
it. If you're looking for accuracy - well, they're all accurate, or
none of them are accurate. It really depends on how YOU want to
define an edge. So at this point you really have to step back and ask
why you are computing edges. There must be some reason. You don't
just find edges for the heck of it. What are you really after? Maybe
edges aren't even the way to go. Maybe you want color classification
or something.
From: Avengeline on 12 Mar 2010 08:36
i just want to find the edge width for every edges.. then divided by the number of edges to obtain a blur metric.. so, what do you say?
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