Diving, Photography and Things - Ian Brennan's Blog

Our Leafy Sea Dragon Video on YouTube

2006-10-11T20:16:00.000+09:30

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

2006-08-27T18:25:00.000+09:30

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)

2006-08-15T21:32:00.000+09:30

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

2006-07-02T08:39:00.000+09:30

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

2006-07-02T08:36:00.000+09:30

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

2006-02-27T08:31:00.000+10:30

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

2006-01-23T21:24:00.000+10:30

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

2006-01-11T08:29:00.000+10:30

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.

MikeSe gets exposed

2005-04-26T08:39:00.000+09:30

Mike Seyfang got plenty of exposure over the last two weeks. He and I worked at Microsoft together in Australia.

He's recently left to start up Learndog. This week he got coverage in The Australian and last week he was in The Adelaide Review. Both can be seen over at his Blog site so I won't post the stuff here.

The Adelaide Review piece didn't quote him (or Cameron Reilly (mispelt in the article) - another MSFTie). I get the feeling that it was an article put together from reading other blogs... there were no quotes from either person - even though they are regularly online and would probably have given a quote.

The Australian actually spoke to Mike (or at least attributed a quote to him).

So what do you call a paper article written by reviewing online blogs? Mike - got an idea?

Dive Review: Live aboard Diving on the Undersea Explorer

2005-03-20T13:44:00.000+10:30

Got back from a week living onboard the Undersea Explorer. http://www.undersea.com.au/ They visit Australia's best dive sites on Australia's Great Barrier Reef and Osprey Reef - in the Coral Sea. This isn't a day trip to the reef, but a six-day expedition into wilderness. The facilities are top-rate and the food was amazing (thanks Erwann). There were 20-odd explorers and six-or seven crew members. Some of the group were a team doing Reef-Watch work both in the GBR and Osprey reef. Undersea Explorer runs a research programme as well as explorer trips for us divers. We were so far out into the Coral Sea that I'm sure we had 4 days without sighting another ship! That's some wilderness trip. We got to see sharks close up.

You can see photos from some of their recent trips over at http://www.undersea.com.au/index_photographs.htm

If you're over this side of the world and dive - this is a must-do trip.

Colour Balance and Underwater Photos

2005-03-04T08:01:00.000+10:30

The Pentax Optio S5i has a "marine" mode that sets the color balance for underwater photography.

Water filters out red light from the sun and so it leaves a blue cast. Depending on the sunlight, the water clarity, the depth and even which way you're facing impacts the level of blue.

Also, the deeper you go the more the other colours are filtered, until there's just blue.

The Optio has a marine mode that compensates for the reduction of red light - it's in effect a digital filter inside the camera.

It looks like the camera is geared more for shallow diving rather than deep diving. Also in close-up it works very well.

But on images that are a little further away there's still a colour cast. We've tried Video Pilot on some of our movies to reduce the cast. You can see the results here taken at Port Turton, Australia in a before-and after movie (reduced for web download).

One of the good things about this tool is that you can fix the cast up once for a movie, then use the "palette" to fix other movies taken at the same time and depth.

Another cool thing is that it's not just about white balance. Let's say there's a movie with me diving, and my hand is in view. I could find another image that showed my hand (or maybe my face) and take that "above-water" flesh colour as the basis of the balance - basically tell the program that the two images share the same colour palette.

We'll keep you posted on how it works on our upcoming scuba dive holiday.

A review site of the Pentax Optio S5i

2005-03-01T07:51:00.000+10:30

Over at Steve's Digicams site there's a detailed review of the Optio S5i and a gool shot here

that shows the size of the camera.
This was one of the reasons we chose this camera - not only does it do lots, it's small and has underwater support.

Rapid Bay Jetty

2005-03-01T00:15:00.000+10:30

One of the most beautiful dives in South Australia. It's also one of the most run down sites.

This was originally a deep sea jetty for the cement works that still stand (disused) on the coast. After it was handed over to the State in the 1980's it fell into disrepair. A storm a few years ago damaged it and since then the powers-that-be have not come up with a plan to maintain it.

Where divers once had to take a 700 meter walk to the end of the jetty, they now have a swim from the shore. This is because the jetty has recently been closed off to both anglers and divers.

Petitions have been raised to try and get it open for recreational use, but to date there's no joy.

The good thing about it is that there's a renewal of growth in sea life, including the dragons, cuttlefish and fish.

I'll post some photos at a later date.

Sample Pentax Optio S 5i Video

2005-02-28T08:41:00.000+10:30

Our first camera - a Coolpix 995 - stored videos in MOV format which was pain.

The Pentax Optio S 5i saves video files in AVI format, which means they're really easy to work with without buying extra software. As I said earlier, we've used Microsoft Movie Maker (the one that comes with Windows XP) to edit them.

Here's a sample of underwater video with the camera. It's now in WMV format and I've compressed it to get it to a resonable size for download. The compression means it's more grainy than in real life, but you'll get the idea.

Movies with the Pentax Optio S 5i

2005-02-26T18:50:00.000+10:30

There is a movie mode for this camera - and a marine mode (that's what the "i" means). Combine them together and you get underwater movies!

The resolution is quite small at 320x240 - but it's fun to have a palm-sized camera that can shoot as much movie as your memory card can hold.

We've taken these movies and blended them in with stills using Movie Maker. Initially the results were average - user problems - but with perseverance we're getting some fun out of it.

When I get the time I'll take you through what can be done with Movie Maker.

Leafy Sea Dragons

2005-02-18T12:54:00.000+10:30

One reason we like diving in South Australian waters is to find these animals. They are the aquatic emblem of SA.

This photo was taken under Rapid Bay Jetty using our first outing with the new Pentax Optio S 5i (Click here for larger image) of a Leafy Sea Dragon.

WA Fisheries has a detailed page on these endangered species.

Diving and Photography

2005-02-07T18:39:00.000+10:30

I've been diving for a few years with my wife Jo. We've recently bought our 2nd digital Camera - an Pentax Optio S 5i with an optional underwater housing. It's added another dimension to our sport.

Here we'll explore the place where the sport and hobby intersect and will post lessons we've learnt and fun we've had and places we've seen.