iPhone Panorama Stitching
All photos on my travel blog have been shot with a 1st generation iPhone. The picture quality at the original resolution of 1600×1200 is lousy. However, if you scale them down to something tiny like 640×480 it’s actually alright for my purpose: posting them on a blog or sending them by email.
I wondered how difficult it would be to stitch panoramas from those grainy, blurry iPhone photos and those images in my previous post are the result. I used the free open-source toolset Hugin. It’s 0.8 version for Windows is a bit difficult to find, and you need at least that version for the photometric white balance compensation, so here’s a link to a pre-compiled EXE installer.
I’m amazed at how mature the imaging algorithms are, or that those algorithms exist in the first place (and I’m working with digital images on a daily basis :-)). Hugin not only managed to undistort and blend the images perfectly, it also removed the camera’s vignetting and compensated for the difference in exposure. This is an important bit because the iPhone adjusts its shutter speed automatically which is usually a bad thing for panoramas.
The only thing I had to do (apart from clicking two buttons) was entering the camera’s focal length. It’s not included in the EXIF data which is a bit of a disappointment. Maybe Apple wanted to hide it from other smartphone manufacturers? Well, google turns up the required data pretty quickly. The iPhone (2G) has a film-equivalent focal length of 37mm or a field of view of about 50 degrees.
Of course the final panorama doesn’t allow for severe color corrections. The colors are dull (it was an overcast day as well) but you could play around a bit more to create a more vibrant result. Anyway, it’s good enough for me to snap some more in the future for my Shanghai reports. Stay tuned!
Airports and Laptop Batteries
Since I’ve just flown across the globe to China, this comic from xkcd seems a bit familiar I must say 🙂
No Dogs Allowed
That must be the craziest “no pets allowed inside this store” sign I have ever seen. At least they didn’t choose a panda bear for this sign since walking inside with one of them is as unlikely as having my dog carry a bottle of schnapps.
Shanghai Photos 1
A few impressions from around our office on Yuyuan Lu. The dog was wearing 2 pairs of tiny shoes. I didn’t dare to approach the girl for a closeup photo. Besides, a dozen cyclists would have run me over 🙂
Childhood Memories
I still fondly remember a book I had when I was a child. It was about dogs running and driving towards a big tree where they had a party. I couldn’t remember the title though.
Not anymore! I recently stumbled upon its original English version on the internet. It was called “Go Dog Go” and it’s still in print although I couldn’t find anything about a German version. Not even Amazon seems to have it.
But here’s the video version I found on a Chinese video portal. It’s a bit hypnotizing (and probably not by Dr. Seuss at all) but contains all the small details I couldn’t remember anymore (or rather overlooked when I was a child, like the recurring boy-meets-girl-theme).
