Diving, Photography, Software and Things - Ian Brennan's Blog

Our Leafy Sea Dragon Video on YouTube

Jo and made a video compilation of Leafy Sea Dragon footage and posted it up to YouTube.

So far it's not been heavily viewed, but it was certainly a good experiment in how this technology works.

If we get good feedback on this we might do some more from the undersea explorer trips.

Photography: High Dynamic Range Photography

I read an article on the New York Times site this month about High Dynamic Range (HDR) photography.

The essence is simple, the eye is very good at picking up details on, say, a sunny. It can see into shadows and the highlights of the view. Cameras are challenged in this. Cameras, and it seems digital cameras in particular, struggle to get the depth of a scene. A shot of a tree might, for example, expose for the shadow of the tree's trunk, which will overexpose the bright bits of the scene. Exposing for the bring sun on the grass will underexpose the shadow and leave darkness.

HDR works by taking multiple exposures of the same subject, but having some shots over exposed and some under exposed to capture the dynamics of the subject. You then use certain techniques to bring the image together.

My old camera is a Nikon Coolpix 995. As you can see from the picture it looks very clunky when compared with the current range of sleek digital cameras.

One of its main strength when it came out in 2001 was that it was an auto/manual camera with most of the features of an SLR. In particular it does auto bracketing and multi-shots.

As I researched HDR, I found a site Photomatrix that has a beta of some Windows HDR software. I downloaded it a week or so ago and had a look at it. There are some sample images you can use to explore the software. I was impressed

So today I took my old Nikon with me out on a bike ride up to Morialta national park. It was early morning and I thought that the contrast of the morning sun and the deep shadows of the gully would test the HDR software.

The results are quite interesting. Here are the three photos that were exposed.

The auto-bracketing of the Nikon meant that I just had to brace myself against a tree and keep the stutter release button down until the shots were done.

You can see that the camera has over exposed the first image, but this does bring out the detail under the log and the tree to the right of the image.

Back at home, I fired up the HDR software and loaded up my images. Following the instructions from the help file I tested some of the settings of the program. The result was impressive.

The program constructed a hybrid photo where the detail of each image came together to make an image that looks much more like the human experience of the scene. Notice the tree on the right, the bark detail from the three photos has been brought together so you can see the texture from the first image but the texture from the last image.

I found this a great opportunity, not only to dust down my old camera, but to look for other opportunities to try out this technique.

I'll keep you posted!

Microsoft Live Writer (beta)

Just downloaded and tried out this editor. For a free editor is seems pretty easy to use.

Here's a picture inserted from the tool that should get posted to the site directly...

interestingly when I tried to post this nudibrach photo of Jo's to the site, Microsoft Live Writer was smart enough to know that it couldn't post images through Blogger. It asked for an FTP site to post to. Since we own this site, the FTP details were not a problem.

This tool automatically posted up the full image and generated this thumbnail as well.

I'll be looking into this more over the coming days.

Show lost Windows XP Recycle Bin

I was on a corporate network today and accidentally deleted some files (what, that's never happened to you?).

The Standard Operating Environment (SOE) that was defined doesn't have the recycle bin on the desktop (don't know why) and the SOE is so locked down that you can't do the right-mouse click on the desktop trick to turn it on - the option doesn't appear. So I had to find a way of getting to the Recycle Bin.

Digging through Google I found no simple VBScript that would do the job for me. So Here's 3 lines of VBScript that will open up the Recycle Bin for Windows XP - even if it does not have an icon on the desktop. You have to be able to save this VBScript to a directory to run it.

Running the script will open Explorer showing the Recycle Bin.

Cut the lines below into a VBScript file. Note the long line of code may wrap.

'~~~~ RecycleBin.VBS~~~~
set WshShell = CreateObject("WScript.Shell")
dim lReturnValue
lReturnValue= WshShell.run("explorer.exe /root,::{645FF040-5081-101B-9F08-00AA002F954E}", 1)
Set WshShell = nothing
'~~~~ RecycleBin.VBS~~~~

Enjoy!

Image Resizer

Here's the executable code for the Resizer described in an earlier post. It's a single MSI file that installs on your machine.It requires the .Net 1.1 Runtimes.You can download it here.

Changing Sharepoint Image Sizes

In an earlier post we discussed the challenge in keeping Sharepoint Picture Libraries down to a manageable size. We've created this application to help squeeze images down to size.

Modern digital cameras create very large images, but in many cases there’s no point in having an image larger than the screen. This application reduces the size of your pictures to a specified size. There are 3 steps once the application is loaded.

Set the maximum size for the converted images. The default is 800 pixels by 600 pixels
Select the images to convert
Identify the output directory for the new images

You can see the screen shot here. Note that this "thumbnail" was produced using the program!

When you click the "Convert Files" button, the source images are processed. The proportions are kept, so if an image is reduced from 1200 pixels wide to 800 pixels, then the height is kept to the same proportions.

If the source image is smaller than the given dimensions then it is not adjusted.

This application has been tested accessing images on a Sharepoint server directly (as described here). It has not been tested saving the new images back to the server.

Don't forget that replacing the Sharepoint Picture Library images is easy. When you go to the Library and Upload an image there’s a “multiple Items” link. Click that and you can select the modified images and upload.

[Note]

This is a first release of this resizer. I would suggest that you copy any images to a working directory before using this application, just in case the size of the created files are not to your liking.

This application has not been tested where the output directory is the same as the location of the input images, so we don't recommend trying this as it could delete your images!

Hunting for U-boats

or Triangulating for Viruses and Spyware

I was surfing the internet a while back when Microsoft’s AntiSpyware popped up to say that something had got through two firewalls, my anti-virus software and managed to get itself into my machine.

I had arrived at the page in question via my search engine (Google in this case). I reviewed what had happened and it seemed I had picked up a malicious JavaScript attack.

That got me thinking. With all the technology pieces I had in place this thing still got through. What about those who don’t have security in depth. The battle against these vandals is flawed. It relies on me being constantly on my guard and always being up to date. Anti-virus doesn’t stop me getting the code, it just checks it before it runs. AntiSpyware works in a similar way. I would prefer is not to have the stuff come down to my PC in the first place.

Is there a way to leverage the experience of people like me to help protect the rest of the internet population? Why does anyone else have to experience the pain of undetected code getting onto their machine?

There must be a better way. I was thinking this was beatable. I recalled when I first read Robert Harris’ 1995 book Enigma about their attempt to break the German Naval code of that name.

[WARNING: PLOT SPOILER]
An American convoy is being stalked by U-boats and the British cannot break the naval code (Enigma) to give advance warning. Once the 1st U-boat finds the convoy it sends its coded location and the course of the convoy to the other U‑boats. These are picked up by the British as “cribs” – partial solutions to the cipher. As each U-boat starts to tail the convoy they also broadcast their location and course. This collection of “cribs” is eventually enough for the British to crack the code.
[END OF PLOT SPOILER]

What’s this got to do with virus hunting? Well there are 2 main ways to get viruses today – by email and by the internet. Email viruses, by their nature, come in randomly and hide their source location. But normal anti-virus software should address this. But what if you find it off the internet? Here we could use triangulation and logic.

Fact: Most sites are found from search engines. Therefore removing dubious sites from the search results should reduce the risk for all internet users.

But how to identify them? Well software like Microsoft’s AntiSpyware and other anti-virus vendors could help. As each type of protection triggered an event, it could anonymously alert a central point with details of (say) the last dozen URLs visited. Perhaps derived from the browser or a plug-in.

Each of these alerts gives us a "crib" into the location of the bad site. As more people tripped over this site more data would be collected. Eventually a pattern would emerge. Once a threshold had been reached the site would be blocked from the search results. Maybe even referring sites would be blocked.

There would need to be an opt-in stage to ensure that users explicitly permitted the forwarding of anonymous data. To manage data quality, there would need to be guarantees that only real users are submitting data; if this wasn’t done then malicious people could submit sites to be blacklisted. So there would need to be some form of certificate (GUID, public key etc) to encode the posting. There might also be a throttle on the number of posts from a client per 24 hours to ensure there was no rogue code abusing the system.

I could imagine the central agency would need to process many different file types and have a library of known exploits and a method for addressing them.

Or perhaps the agency just aggregates the data and circulates the list of sites that have exceeded the threshold. The search engine company could either confirm the presence of malicious code themselves or partner with another software company to provide this service. Anti-virus and AntiSpyware software manufacturers would obviously have such expertise.

Of course a company that has a search engine, AV skills and has browser technology would be in a strong position to lead this.

In this way we establish a feedback loop to ensure that only low-risk sites are presented to us.

[I need to think about how to manage false-positives - valid sites that got caught up in this collection and review process]

Managing the Size of Sharepoint Picture Libraries

Our corporate Sharepoint site is a big hit. We’ve set it up so that each department has its own sub-web that they maintain.This is a great win for the company because it means that department intranets become self-managing. The Information Technology team can then focus on other things and don’t become a “bottle-neck” in the delivery of intranet services.The down-side of this is that the size of the sites can get out of hand. I was doing a review of usage of the sites and found some very large Picture Libraries. Further investigation showed that users had uploaded digital photographs onto the site. That’s great, it’s what we want them to do. But unfortunately it means that the site has become large and slow to load.Reducing the size of each individual image would be time-consuming. But I’ve got some ideas for a tool to process these images in bulk and reduce the size.