Survol des équipements vidéos pour collection de données

This is a quick overview of currently existing and/or available technologies for transportation video data collection. The information herein is current as of February 2014.

Technical requirements

• Capacity for six or more hours of independent operation, including :

1) Compatibility with and availability of external battery packs

Cameras are near-universally limited to at most two or three hours of video capture with their internal batteries alone. Use of external battery packs therefore unavoidable, and must be taken into consideration during selection.

It should be noted that the department currently has two battery packs compatible with all devices that can charge via USB.

2) Video storage capacity Though very high-capacity memory cards exist, cameras vary in both maximum supported size (often a hardware limitation) and video storage format. External memory being an impractical - if not impracticable - solution, cameras must accept internal cards of sufficient capacity to record more than six hours of continuous video, at a resolution of at least 1280x960.

• Wide viewing angle

Standard camera lenses have a viewing angle of less than 90 degrees. Unfortunately, given the constraints on camera placement in most sites (often in close proximity to the subject area) a wider viewing angle is preferred despite the inherent distortion this causes, which must be corrected.

• Resistance to the elements
• Convenience and ease of setup

The department currently has equipment to both house and encase a sufficiently small camera (the currently used GoPro Hero 2) as well as a 12 meter extendible pole for attachment to existing poles on-site,

Camera types

Pointe-of-view or "extreme-sports" cameras

These cameras are designed to be lightweight, rugged, easily attached to both persons and equipment, and tend to have wide viewing angles in order to better simulate that of a person. They also tend to be relatively inexpensive. They are therefore excellent choices for video data collection, though the distortion caused by the lenses must be corrected for (work ongoing by Nicolas Saunier and Paul St-Aubin).

	GoPro HERO2	GoPro HERO3	ContourROAM2	Contour+2	Sony POV Action Cam	Drift HD Ghost
Maximum resolution	1080p	4K	1080p	1080p	1080p	1080p
Price ($CAD)	(discontinued)	399.99	269.99	360.00	299.99	349.95
Viewing angle(s) (deg)	170, 127, 90	170, 127, 90	170	170	170	160
USB charging	Yes	Yes	Yes	Yes	Yes	Yes

All of the above cameras are capable of recording at 960p at 30 fps or more.

Surveillance cameras

The vast majority of surveillance cameras are for fixed use and require bother external power and memory. Those that do have some on-board capability are limited in both frame-rate and resolution, and cannot generally be charged while in use.

Machine-vision cameras

Many companies specialize in machine-vision equipment, including notably Edmund Optics and Allied Vision in Canada. Though these companies provide a wide range of products of interest and have some experience in traffic monitoring, the principal advantage of their products over more mainstream solutions is largely in connectivity and live data transfer - aspects of relatively little use in current applications within the department. Said focus on connectivity also means that none of the companies investigated offer a camera with on-board power or memory, and all are more delicate than equivalent point-of-view cameras. While representatives at Allied Vision offered to create a custom assembly, the total cost (quoted as "starting at $1500") is not matched by any significant advantage.