MATLAB: websave function doesn't save the image - matlab

I am using the following function to save map from mapquest as a png file as follows
f_name='abc.png';
url='https://www.mapquest.com?center=1.34,103.683'
%other parameters also go through the url.
websave(f_name, url);
Image is saved but it cannot be displayed throwing the following error.
Error using imread>get_format_info (line 543)
Unable to determine the file format.
Error in imread (line 391)
fmt_s = get_format_info(fullname);
Subsequently following line also throws an error.
[M, Mcolor] = imread(filepath);
When image is opened a message is displayed
File format is not supported.
But if its extension is changed for example to html it does try to load the actual web page display.
Any clues will be highly appreciated

Finally I managed to find the way to do this after a little research!
Static APIs are used in this regard and are available with maps like Google, Mapquest etc.
These static APIs convert the web page of map to its respective image, to put an example for Mapquest it can be used using this

Related

Extrapolate Coordinates form Leaflet map

I'm planning a climbing trip and I wanted to retrieve the climbing locations from a leaflet map.
I thought I could use chromedriver and selenium to get the information I wanted but I'm having difficulty scanning through all markers since I can't understand where all the informations are stored.
Could someone guide me through how I could get the information? (also without using selenium)
The map in question is: https://www.climbingsardinia.com/topos/maps/
Thank you in advance.
in that page you will see a global variable called cttm_markers, it contains all markers informations and relative coordinates.
For example, cttm_markers[0][[0].additionalData.title evaluates "M.te Arci – Trebina Longa".Further, cttm_markers[0][[0]._latlng is an object {lat,lng} that contains coordinates.
Try to open console and paste this: JSON.stringify(cttm_markers[0].map(c=>({title:c.additionalData.title,latlng:c._latlng}))), it will print a json.
One way to do it is to get some information on one of the markers and use this to search the request reponses made by the page (you can do this in the debug tools, usually opened with F12). One of the markers for example reveals the location "Grighini". The base request redirects to (in my case) https://www.climbingsardinia.com/topos/maps/?doing_wp_cron=1651158093.0027918815612792968750
Searching the response, reveals that in line 1908 there's the string "Grighini". This line contains a serialized JSON array, containing the markers.

leaflet shp-write to convert geojson to shapefile

I'm trying to convert a Geojson to a zipped shapefile using shp-write.
But when I follow the example given on the GitHub page https://github.com/mapbox/shp-write#example
I'm getting a "ReferenceError: require is not defined" error on this line:
var shpwrite = require('shp-write');
This question was posted at Converting Geojson to Shapefile in Javascript using shp-write, but I was unable to access the updated file at https://jsfiddle.net/rajkishan16/3xff9zmy/
Can someone help me?
Thanks.

How to Convert IPicture to Image - .NET 4.5 TagLib Sharp

I am wanting to display the album artwork of a song (accessed via the taglib-sharp library) within a Windows Forms picture box. The problem I'm running into is that the taglib-library returns an image of type TagLib.IPicture whereas the picture box requires an object of type System.Drawing.Image.
I have scoured the internet for many hours now, looking for a way to convert from an IPicture to Image, but to no avail. The best lead I have is this: http://msdn.microsoft.com/en-us/library/system.windows.forms.axhost.getpicturefromipicture.aspx, but I have yet to see a successful example of how to implement this.
Any help as to how to convert between these two types would be much appreciated. Note: IPicture is not analogous to IPictureDisp in this case.
I've done the opposite before - turning an existing .jpg into an IPicture for embedding in an .mp3 file. I just tried reversing that operation and, after tweaking and testing, came up with this:
TagLib.File tagFile = TagLib.File.Create(mp3FilePath);
MemoryStream ms = new MemoryStream(tagFile.Tag.Pictures[0].Data.Data);
System.Drawing.Image image = System.Drawing.Image.FromStream(ms);
Thanks for the question - I already know how I'm going to use this myself!
Update: Here's the other way (.jpg to IPicture that I've done before):
tagFile.Tag.Pictures = new TagLib.IPicture[]
{
new TagLib.Picture(new TagLib.ByteVector((byte[])new System.Drawing.ImageConverter().ConvertTo(System.Drawing.Image.FromFile(jpgFilePath), typeof(byte[]))))
};

Dicominfo not giving all metadata

I have a dicom from a GE MRI scanner and there are a few pieces of information in the header I require (namely the relative position of the scan). I tried using info = dicominfo(filename) but, for some reason, this piece of information does not show up. I know that this information is saved, however. It might be a private data, but I'm not completely sure. If anyone has any information on how to resolve this issue that would be greatly appreciated.
Try using the dicomread function instead, it should be more versatile than dicominfo and it reads the information files too. If this doesn't work then it means that the information you are trying to obtain is not made available by GE.
Or use gdcm to dump the private GE header:
$ gdcmdump --pdb input.dcm

MATLAB: force doc command to open a specified reference HTML page

Say I've written a class in a package, called mypackage.myclass. I've written my own HTML documentation for the package and the class, and have included this within the MATLAB help browser as described in the MATLAB documentation.
I can display this HTML documentation by using the help browser to navigate directly to it, but typing doc mypackage.myclass does not display it; instead it displays some HTML documentation that is auto-generated by helpwin (which is a nice feature, but not what I want - the auto-generated documentation is too techy for my users).
How can I force doc to display my documentation, rather than the auto-generated documentation?
Equivalently:
When you run doc docTopic, inside the doc command the Java class com.mathworks.mlservices.MLHelpServices.showReferencePage(docTopic) gets called. If a reference page for docTopic exists, it displays it and returns a success value. If a reference page doesn't exist, it returns a failure value, which then causes helpwin(docTopic) to get called. Somewhere there must be some catalog that connects values of docTopic with individual reference HTML files. How can I fiddle with that catalog - or can I create one for my package?
MathWorkers and #Yair, please give me enough undocumented rope to hang myself with :)
As far as I know this is not possible and not intended by MathWorks. I don't know of an undocumented way of doing this either. As far as I remember the keywords for doc are hard-coded somewhere.
Depending on your setup you can try the following: Prepare your own doc command that uses web(..., '-helpbrowser') to display HTML pages in MATLAB's help browser:
function doc(topic)
my_topics = {
'foo', 'foo.html'
'bar', 'bar/help/intro.html'
};
for i = 1 : size(my_topics, 1)
if strcmpi(topic, my_topics{i, 1})
web(my_topics{i, 2}, '-helpbrowser');
return;
end
end
% Fall back to MATLAB's doc. Note that our doc shadows MATLAB's doc.
docs = which('doc', '-all');
old_dir = cd();
c = onCleanup(#() cd(old_dir));
cd(fileparts(docs{2}));
doc(topic);
end
If you put that function in a file doc.m and put the corresponding directory at the beginning of the MATLAB path (see help addpath) then it will be called instead of the built-in doc.
Of course you could use some other place to store your custom doc mapping (a file, for instance) or use some kind of dynamic lookup scheme.
UPDATE: As of MATLAB R2012b, the '-helpbrowser' option of web is undocumented. This is probably related to the GUI changes in that MATLAB version, which also include the help browser. web(..., '-helpbrowser') still works as intended, but that may change in future versions of MATLAB. As far as I know, there is no documented way of opening any HTML page in the help browser in R2012b.