Comments on: Locating the US continental divide, part 1 – Introduction

By: Steve

Steve — Wed, 14 Sep 2011 12:51:54 +0000

Matteo—Use imfill to fill the “holes” (low spots) in the image. Use > to find where the filled image is greater than the unfilled image. Use bwareaopen to eliminate small basins. Add the remaining large basins to the marker used for imimposemin.

I’ll add this to my list of potential topics.

By: Matteo

Matteo — Sun, 21 Aug 2011 03:43:44 +0000

Hi Steve,

Thanks for your comment.
I was more thinking along the lines – if there were significant endorheic basins, like the Wyoming bulge in Bit Player’s post, or larger ones, like there are in every continent, e.g.
http://en.wikipedia.org/wiki/File:Ocean_drainage.png
how would you go about keeping them instead of eliminating them using imimposemin (if I understand your reply).
Any way to do it without having to use a marker?
Thanks a lot. Matteo

By: Steve

Steve — Wed, 17 Aug 2011 02:03:18 +0000

Matteo—If I understand your question correctly, then I would say to use imimposemin. This technique is discussed in part 5 of this series.

By: Matteo

Matteo — Tue, 16 Aug 2011 02:37:24 +0000

Hi Steve

Brian’s blog post on the divide on Bit Player shows that he had to go around endorheic basins (I am not too sure he calls him that – it’s the basins that are not connected to the ocean)
http://en.wikipedia.org/wiki/Endorheic_basin
Have you given any thoughts as to how that could be handled in Matlab?
Thanks
Matteo

By: Steve

Steve — Mon, 18 Jul 2011 15:27:07 +0000

Dr. El-Sayed—You were close:

I = imread('http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg');

By: Dr Ihab El-Sayed

Dr Ihab El-Sayed — Fri, 15 Jul 2011 15:12:43 +0000

Cropping or reading Image from web address
Dear Steve,
I am trying to use “imread” to read image from a local web Address
It appears after calling it like this:
I manage to to get the image I need from the D-Link IP Camera by :
using the following in Matlab.
web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg
I am trying now to use the command “imread”
I tried the following, as you are aware it is difficult to get consultant in Jazan area in short time.
My question is very simple , I will really appreciate your prompt reply on this issue,
How to read the image in the above web link as a variable “I”?
The following is my guess but it did not succeed.
Many thanks in advance for your help and support
Ihab

web http://192.168.1.3/image.jpg
>> web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg
>> ImageURL=web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg
??? ImageURL=web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg
                 |
Error: Unexpected MATLAB expression.

>> ImageURL=['web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg'

ImageURL =

web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg

>> ImageURL=['web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg'

ImageURL =

web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg

>> edit web
>> strmatch(fname, ['netscape';'Netscape'])
??? Undefined function or variable 'fname'.

>> fname=polic11.jpg
??? Undefined variable "polic11" or class "polic11.jpg".

>> fname='polic11.jpg'

fname =

polic11.jpg

>> strmatch(fname, ['netscape';'Netscape'])

ans =

     []

>> strmatch(fname, ['netscape';'Netscape'])

ans =

     []

>> I=strmatch(fname, ['netscape';'Netscape'])

I =

     []

>> imshow(I)
>> I=strmatch(fname, ['web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg')

I =

     []

>> imshow(I)
>> I=getimage(strmatch(fname,['web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg'))
??? Error using ==> imhandles at 81
The handle must be a valid graphics handle.

Error in ==> getimage>parseInputs at 223
him = imhandles(h);

Error in ==> getimage at 86
him = parseInputs(varargin{:});

>> I=getimage(strmatch(fname,['web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg'))(strmatch(fname,'web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg'))
??? Error: ()-indexing must appear last in an index expression.

>> I=getimage(fname)
??? Error using ==> getimage>parseInputs at 217
GETIMAGE: Invalid handle H.

Error in ==> getimage at 86
him = parseInputs(varargin{:});

>> I =imread(['web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg')
??? Error using ==> imread at 293
Can't read URL "web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg".

>> web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg
>> I=imread('web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg')
??? Error using ==> imread at 293
Can't read URL "web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg".

>> I=imread('web http://l1.yimg.com/i/i/ab-mk/metro/polic11.jpg')

could you please help me to read the image from the browser programmatically and place it as a variable in my workspace.
Many thanks in advance for your understanding and cooperation, I am giving a summer course now to the students and they need to know how to do this.
Best regards,
Dr . Eng. Ihab El-Sayed
Assistant Professor Faculty of Engineering
Department of Industrial Engineering

By: Steve

Steve — Mon, 24 May 2010 15:28:40 +0000

Arni—Thanks for the pointer.

By: Arni

Arni — Fri, 21 May 2010 17:49:46 +0000

Hi Steve,

I found this interesting blog post on use of watershed for stitching 2 pieces of a panoramic view.
http://www.cb.uu.se/~cris/blog/index.php/archives/76#more-76

By: Steve

Steve — Fri, 04 Dec 2009 18:33:15 +0000

rzsh5—You can construct any colormap you like in MATLAB. You are not limited by the colormap functions we provide. You can even read the exact colormap used to display the images on that web page:

[X,map] = imread('http://www.ngdc.noaa.gov/mgg/topo/img/gtanew.gif');

By: rzsh5

rzsh5 — Tue, 24 Nov 2009 09:49:52 +0000

Great job!
I have a question, I tried to plot the data into the same color as the one posted in NGDC gallery (http://www.ngdc.noaa.gov/mgg/topo/gltiles.html), however, I tried all the colomaps in Matlab, I couldn’t get the same color assignment, any one know what kind of colormap should be used? Thank you. rzsh5@hotmail.com