Creating an image from a URL

[yelnic]

We have a rather bizarre issue here, and I was wondering if anyone had any ideas:

The Windows API exposes the call IExtractImage, which, among other things, can extract a bitmap from a URL link. It works quite nicely, except that it doesnt work in XP. The call is still there, but apparently doesnt supported extracting images from URLs in XP.

Now, XP does create thumbnails from html in Windows Explorer, so I know the functionality is there. The question is: where is it? Where did they hide it? Ive seen one product (html2jpg) that basically does this, but nobody seems to have noticed that this functionality is not available in XP. The reason that this is an issue is that if a server is updated from 2000 to XP, we would lose the ability to create thumbnails on the fly for clients.

Any help would be greatly appreciated

 

[Derek Stone]

You can download the image file directly using the [msdn]System.Net.WebClient[/msdn] class, unless theres some particular need for the API, that is.

 

[yelnic]

this converts html to an image?

Im not sure were on the same page. Basically, I need to convert html (googles home page, for instance) to an image. I have no image resource to download. Im looking at System.Net.WebClient, and I dont see any mention of taking a URL and converting into a jpg/bmp/whatever...unless this DownloadData() method is more powerful than it looks. Is there something Im missing there?

Thanks
mike

 

[Derek Stone]

The way in which you worded your question led me to believe you were asking for something slightly different. WebClient will not work for such a task.

Steve McMahon from vbAccelerator has an example that you might just like however: Thumbnail Extraction Using the Shell.

 

[yelnic]

Unfortunately, that uses the IExtractImage call from the Win API. It works perfectly in all versions other than XP.

It pulls an image perfectly on my 2000 box, but just leaves a blank on the XP machine.

Somehow, XP is doing this for Windows Explorer, but has hidden the call (or made it unavailable). I have no idea why they did so or where it might be now.


mike

 

[dynamic_sysop]

not sure if this link helps, its done in C# and uses IExtractImage ...
thumbs using IExtractImage

 

[Derek Stone]

The code runs smoothly on Windows XP, yelnic. Steve McMahon developed the application on it and I just tested it. Theres something different with your machine.

 

[yelnic]

odd

that is strange if it worked with URLs for you---it only works with images on every XP box here---are you running an unusual setup?

 

[cbeckner]

Has anyone found an answer to this yet?

 

[privateer]

Looking for a solution to this as well

Hey, is it possible to use the old shell32.dll file? Before service pack 1 or 2 it did work, so, shouldnt it be possible to register the old dll under another name and use it?

BTW, you can check this out as well:

http://www.nbrandt.com/html-preview-xp-thumbnails.html

it talks about how to revert the setting change. It isnt actully a change in the shell32.dll file itself.

Let me know if you find a solution, and I will do the same.

 

[privateer]

More sites that I have found.

Microsofts note about removing this feature:

http://support.microsoft.com/default.aspx?scid=kb;en-us;327833

Microsoft telling you how to use the feature(but without web documents):

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dv_vstechart/html/shareptthum.asp