Wednesday, 10 March 2010

Defishing Video


A few months ago I wrote about defishing fisheye photographs with software, and I've long been curious as to whether I could apply the same ultra-wide effect to video footage. It turns out that I can, although it is time-consuming and laborious. The video above is an example of some footage shot in London's Natural History Museum, and also the area outside London Waterloo.

Amongst its many options VirtualDub can export video to a sequence of still frames, which is what I did. Ten seconds of timelapse footage at 30fps equals 300 still frames, which I then processed as a batch with Panotools. I have since been informed that the popular and surprisingly valueful image retouching software DxO Optics will do this automatically, and after having a look at the trial version I'm impressed, and slightly worried that I hadn't heard of it before. N.b. I am not being paid to advertise the quite wonderful functionality of DxO Optics, although if they want to send me the Elite version and a t-shirt and some Edam cheese - I love Edam - I would not object.

See, when I was a kid I couldn't stand Edam. It had a bland, hollow taste that did not appeal to me. Now that I am older and more attuned to the world's subtleties I realise that Edam is in fact the King of Cheeses; tasty, healthy, and also compatible with the modern age. It is industrial cheese. Cheese with the scaffolding left in place. Perhaps the only cheese that could survive the vacuum of space and subsequent re-entry. The only cheese that could be inserted into an elephant's bottom, removed, and it would still be palatable. The bright red waxy coating would make it easy to spot amongst the elephant dung. If only it lit up. I'm not being paid to advertise Edam, but trust me, it's a great cheese.

Still, once I had the individual frames in my sweaty right hand I simply assembled them with Virtualdub and added borders so that the image was a sensible resolution - XVid and DivX have trouble compressing footage if the vertical and horizontal resolution are not whole numbers - and I then assembled the clips results with Windows Movie Maker and added a soundtrack of my own devising. It took an age to defish the individual frames, a process that tied up my main computer when I could have been doing other things. In future I might press-gang my Asus Eee netbook into use as an overnight frame defisher.

There was one problem that defeated me. The video has a flat look caused by a lack of contrast. The black bars at the top and bottom should be the same black as the background of this blog, but they're brighter. As I understand it this is a common problem caused by inexperience, which is fair enough because video is not my field.