About

The eLog library was initially developed as a research prototype and later published for lifelogging researchers in 2010 to help them easily analyze heterogenous data and complex visualization. It has been kept growing with the progress of mobile computing environments and recently its UI part is released with GPL v3 license for wider usage. The eLog UI library is optimized for mobile environment and can get easily integrated with existing Web services.

Who We Are

The original work was proposed by Pil Ho and later extended the work with collaboration with 28 researchers around the world who contributed their lifelogs, collaborated for lifelog analysis and share research results to build up an open lifelogging platform for the public. Pil Ho has been keeping the development updating the library following up the progress in mobile computing.

Updates

  • Nov. 2014: Change the web page skin using bootstrap.
  • Nov. 2014: Published elog UI library as GPL v3.
  • Oct. 2014: Version up eLog library and documentation.

 

GoPro 3D system

I've played with this new system time-to-time for two weeks now. Overall I found a number of major benefits and drawbacks to use for life logging experiments. Let's first see its technical specification.

  • Lens Type: Fixed Focus (2ft/.6m – ∞), glass, f/2.8, Super low-light sensitivity (>1.4 V/lux-sec)
  • Angle of View: 170º ultra wide angle in WVGA, 720p, or 960p mode, 127º wide angle in 1080p mode
  • HD Video Resolution Modes: 
1080p = 1920×1080 pixels (16:9), 30 fps, 15 Mbit/s data rate
960p = 1280×960 pixels (4:3), 30 fps, 12 Mbit/s data rate
  • Sensor Type: 1/2.5″ HD CMOS, 2.2µm-sized pixels
  • Video Format: H.264 compression, saved as Windows- & Mac-compatible MPEG4 (.mp4) file
  • Exposure Control: Auto with user selectable center weighted average and spot metering settings, Auto white balance.
  • Dimensions: 130mm x 62mm x 45mm, 350 gram

Originally GoPro HD camera looks designed to capture sport activities where fast shutter speed, small size, light weight, wide view angle, long battery time and the quality of video are important. It comes with many types of accessories for this purpose. 3D camera is an extension to capture a movie in 3D using two GoPro HD camera. All satisifiy the need for life logs.

Compared to ViconRevue, it weighs double and with an enclosing case, it clearly gets heavier. I felt uncomportable when I hang it on my neck, whereas with ViconRevue, I sometimes completely forgot I had it on my neck. So I had to use it with the chest mount (See the picture).

One problem with the chest mount is that acutal video shots tremble a lot as I was walking or moving. This happens equally for ViconRevue, which is a camera that takes a shot every tens of seconds. So for ViconRevue images mostly get motion blurred. For GoPro, videos just tremble a lot. The good part is that thanks to their fast shutter speed captured video frames are cristal clear without any blurring. The answer is then software video stablization.

Challenging problem is becuase I am moving, in other words camera is moving forward, most frame-by-frame matching methods (Feature points matching or phase correlation) do not work well. I am currently working on this matter since without it its 3D video easily gives you a headache.