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From: Erik on 20 Jul 2010 18:32
I believe i compared a breast to a "tapered cylinder". For the purposes of this problem, I think its an adequate description. I'd appreciate help much more than criticism of my word choice.

The problem remains. How to interpolate these slices using information from other slices.
From: Walter Roberson on 20 Jul 2010 18:55
Erik wrote:
> I believe i compared a breast to a "tapered cylinder". For the purposes
> of this problem, I think its an adequate description. I'd appreciate
> help much more than criticism of my word choice.

You've been dealing with the problem for a while, Erik; we onlookers are still
trying to figure out what is needed to be done.

In my experience, small differences in word choice often hint that the person
posing the problem is trying to do something that hasn't been described, or
something more specific than has been described. When we do not probe around
wording oddities, people can end up spending a fair bit of time working out or
describing inapplicable solutions or solutions to a problem more difficult
than the situation calls for.


Besides... we get nine to ten thousand postings here every month. If we can't
banter a bit about some of them, we'd go "stir crazy".
From: us on 20 Jul 2010 19:16
Walter Roberson <roberson(a)hushmail.com> wrote in message <i259ni$f9u$1(a)canopus.cc.umanitoba.ca>...
> Erik wrote:
> > I believe i compared a breast to a "tapered cylinder". For the purposes
> > of this problem, I think its an adequate description. I'd appreciate
> > help much more than criticism of my word choice.
>
> You've been dealing with the problem for a while, Erik; we onlookers are still
> trying to figure out what is needed to be done.
>
> In my experience, small differences in word choice often hint that the person
> posing the problem is trying to do something that hasn't been described, or
> something more specific than has been described. When we do not probe around
> wording oddities, people can end up spending a fair bit of time working out or
> describing inapplicable solutions or solutions to a problem more difficult
> than the situation calls for.
>
>
> Besides... we get nine to ten thousand postings here every month. If we can't
> banter a bit about some of them, we'd go "stir crazy".

i FULLY second walter (as usual, i might add)...
if you cannot take it - better don't visit this NG...
after all, MLbbers ARE living human beings...

us
From: Erik on 20 Jul 2010 23:34
It's no problem. I just felt it was being picky about the wording when we both knew what I meant. If there was a misunderstanding due to the wording that's another story.

Anyways, I guess to help clear up the problem think of an MRI in the coronal view. Cross sections of the breast are taken such that the breast appears as an ellipsoid. To be more specific, cross sections are taken approximately every millimeter. I am trying to mask the breast so as to eliminate information outside of the breast.

So I have these slices every millimeter that each have a set of XYZ coordinates where Z is simply the slice number multiplied by 1mm. These coordinates are eventually converted to binary masks. Occasionally the masking program outputs XYZ coordinates such that the ellipsoid shape is cut by a line. I would like to interpolate the ellipsoid to accurately identify the boundary of the breast.

Because the total volume represents a continuous surface, using information from all of the other slices to interpolate this region, which is missing points, should be much more accurate than doing simple 2D interpolation.

Hopefully this additional information helps. I've been working on this for 2 months now and this small problem is keeping me from calling the project finished. Thanks again for any help anyone can provide.
From: Sean on 21 Jul 2010 09:55
"Erik " <stevesmith121(a)gmail.com> wrote in message <i25prc$7bq$1(a)fred.mathworks.com>...
> It's no problem. I just felt it was being picky about the wording when we both knew what I meant. If there was a misunderstanding due to the wording that's another story.
>
> Anyways, I guess to help clear up the problem think of an MRI in the coronal view. Cross sections of the breast are taken such that the breast appears as an ellipsoid. To be more specific, cross sections are taken approximately every millimeter. I am trying to mask the breast so as to eliminate information outside of the breast.
>
> So I have these slices every millimeter that each have a set of XYZ coordinates where Z is simply the slice number multiplied by 1mm. These coordinates are eventually converted to binary masks. Occasionally the masking program outputs XYZ coordinates such that the ellipsoid shape is cut by a line. I would like to interpolate the ellipsoid to accurately identify the boundary of the breast.

%%%%
Are the lines always in the same location? Are the lines usually in the same orientation?
I think a morphological closing on the binary mask would help you. If the lines are always in the same location (detector non-linearities, blemishes etc.) then you could mask them individually and cover them.
>>help imclose
Note the structuring element can be tuned to specific orientations shapes that your gaps may have. That's why I was wondering about orientation.
%%%%

> Because the total volume represents a continuous surface, using information from all of the other slices to interpolate this region, which is missing points, should be much more accurate than doing simple 2D interpolation.

%%%%
For interpolation with missing points
>>help griddata

%%%%

> Hopefully this additional information helps. I've been working on this for 2 months now and this small problem is keeping me from calling the project finished. Thanks again for any help anyone can provide.

%%%%
So you know I (and I'm sure others) clicked on this thread because of the "humor" tag. They're not always a bad thing.
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