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From: Arvind Prasad on 8 May 2010 02:58
Okay, this is a little complicated. Please read the following statement carefully n try to understand.. Here goes
We have an image. Say, 1500x1200 pixels.
Firstly, we need to read the image and obtain the pixel values of each and every pixel.
Mainly, this program should check whether there is uniformity in the image. That is, there shouldn't be an abrupt change in pixel value at any region of the image.
So, we need the program to select one pixel, and compare its value with few neighboring pixels, say, around 10-15 pixels. We should check that the difference in pixel value should be less than 30% of the maximum pixel intensity in the whole image.
Repeat the same procedure selecting successive pixels, one at a time.

Please give ideas on how to go about the programming part.
Thanks in advance.
From: Rune Allnor on 8 May 2010 03:06
On 8 Mai, 08:58, "Arvind Prasad" <ssr_r...(a)yahoo.co.in> wrote:
> Okay, this is a little complicated.

No, it isn't.

> Please read the following statement carefully n try to understand..

If you had followed your own advice with respect to the
class textbook and other course notes, you would have
found the solution to this homework problem in less time
than it took you to write the post.

Rune
From: us on 8 May 2010 08:20
"Arvind Prasad" <ssr_rulz(a)yahoo.co.in> wrote in message <hs321t$um$1(a)fred.mathworks.com>...
> Okay, this is a little complicated. Please read the following statement carefully n try to understand.. Here goes
> We have an image. Say, 1500x1200 pixels.
> Firstly, we need to read the image and obtain the pixel values of each and every pixel.
> Mainly, this program should check whether there is uniformity in the image. That is, there shouldn't be an abrupt change in pixel value at any region of the image.
> So, we need the program to select one pixel, and compare its value with few neighboring pixels, say, around 10-15 pixels. We should check that the difference in pixel value should be less than 30% of the maximum pixel intensity in the whole image.
> Repeat the same procedure selecting successive pixels, one at a time.
>
> Please give ideas on how to go about the programming part.
> Thanks in advance.

useless verbosity...
all CSSMers want to know is:
what have YOU done so far to solve YOUR particular problem...

us
From: ImageAnalyst on 8 May 2010 08:30
It's not hard or complicated at all. In fact it's so easy that I have
a hard time thinking of a hint to give you. I mean it's literally ONE
line of code - no joke, just one single line. Of course you could do
the brute force method of for nested for loops to scan your image, but
the best way to do it is just one single line of code. Not even a
line - in its most compact form (single letter variables for the input
and output image names) it's only 33 characters long - I actually just
tried it. Even if you did it the "dumb" way, it's less than about 20
lines of code.

I can give you the hints that it involves an equal sign (to assign the
result to a variable) and a greater than sign (to do your 30%
comparison). And if you call the result "b" and the input image "a"
then can you come up with the other 29 characters?
From: Arvind Prasad on 8 May 2010 10:05
"us " <us(a)neurol.unizh.ch> wrote in message <hs3ku7$4al$1(a)fred.mathworks.com>...
> "Arvind Prasad" <ssr_rulz(a)yahoo.co.in> wrote in message <hs321t$um$1(a)fred.mathworks.com>...
> > Okay, this is a little complicated. Please read the following statement carefully n try to understand.. Here goes
> > We have an image. Say, 1500x1200 pixels.
> > Firstly, we need to read the image and obtain the pixel values of each and every pixel.
> > Mainly, this program should check whether there is uniformity in the image. That is, there shouldn't be an abrupt change in pixel value at any region of the image.
> > So, we need the program to select one pixel, and compare its value with few neighboring pixels, say, around 10-15 pixels. We should check that the difference in pixel value should be less than 30% of the maximum pixel intensity in the whole image.
> > Repeat the same procedure selecting successive pixels, one at a time.
> >
> > Please give ideas on how to go about the programming part.
> > Thanks in advance.
>
> useless verbosity...
> all CSSMers want to know is:
> what have YOU done so far to solve YOUR particular problem...
>
> us



I've made a program to compare pixels row wise. You really don't need to know how much of it i've done. Since you claim its a small program, please post the complete program, if possible.
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