Canalview

Projects
Participants	Dramaturg
Skills	coding, cameras
Status	Planning
Niche	Software
Purpose	Fun

The goal is to make something like streetview, but for the Amsterdam canals.

Challenges

• how to make useable 360 shots.
• while on a boat which moves
• reliably add GPS coordinates to the 360 shot
• implement it online? (osm/openlayers/html5/flash?)

Ideas/Brainstorming

Camera stuff

A boat is never ever stationary. Every shot will have to cover 360 degrees instantly (or VERY fast).

Use three cameras in a star-shaped configuration

like this:

         |
      ↖  |  ↗
         O
        /  \
       / ↓  \

Three cameras on a stick. As easy as that.

Use one camera pointed upwards and a reflecting cone

Create a full 360 degree pictures in one picture:

        \  /
  <----  \/  ---->
        ↰ ↱
         __
         \/
         ⬛⬛
         ⬛⬛

To build it we could put an UV filter on the lens and glue a mounting rod to the middle of it, attaching the cone on top of it. (We don't need the center part in this scenario anyway.)

Use a film camera and a rotating mirror

Added diffuculty: need to record mirror position relative to boat heading constantly.

         ⟳ /
          /
         /↱ → → →
          ↑
         __
         \/
         ⬛⬛
         ⬛⬛

Some LIDAR sensors use a similar setup.

Camera mount

The boat will rock. options:

• stable mount that can counter pitch, roll, yaw.
• record tilt with wiimote (or similar) and correct in software.

Positioning

Required precision: few meters, fixed to the canal.

• We need to figure out if a (D)GPS really is acurate enough. If will be severely influenced by the surrounding houses and bridges. We might need to determine our exact position in the canal by using range sensors against the canal walls.
• Add a magnetic compass sensor to record the exact heading of the boat.
• Make sure you use AGPS for faster fix
• Try to keep and accurate speed record (can also use wiimote to sense acceliration) to make corrections afterwards.
• record wifi bssids, for added reference and as backup for gps loss or glitches. (there are (semi) public databases with bssids and precieved gps coords online)

Data gathering

Many cameras are able to store GPS information with every pictures' exif data, the exif spec has a field for GPS location, cameras with gps device can add these in immediately or the data can be added later by using a timed gps log. The later options gives a higher precision (more gps locations recorded), and makes it easier to link with other data like speed and direction.

Justa pointed of the Ceres Solver (Google Code) used in Street View. We can use freely available digital maps of the dutch waterways to cross-reference.

A flying boat?

Does it really need a boat - what about a drone? That would be a more universal approach, as you also could take pictures e.g. of parks and not be limited to canals. Same challenges in regard to drift/position would apply and for 'fly over canal' the added problem of drone crashing into water. Plus side: It would probably more easy to deploy and move compared to a boat.

Requirements

• A boat (sjaan has one that might be suitable)
• Atleast one DSLR
•  ?

Options

webmind can probably arrange a motorised boat in amsterdam and has one EOS350D