Intersections are an important area for using surveillance cameras. Accidents, thefts and traffic congestion are among the many common incidents that cameras can help solve.

However, intersections are particularly challenging to monitor. The scenes are complex with many vehicles and people moving through it. The reflective surface of the cars and their headlights at night make it harder for surveillance cameras to accurately capture details.

Megapixel cameras should provide an important advancement in monitoring intersections as they deliver a significant increase in pixel density relative to traditional CCTV cameras. How much of an advancement is it really and under what conditions?

In this report, we share our extensive findings from a real world intersection test. We went out to a busy intersection with a kit of 7 IP cameras (including SD, 720p, 2MP, 3MP and 5MP from Arecont Vision, Axis, Bosch, IQinVision and Sony) to better understand the tradeoffs for ourselves. As the image below shows, we captured most of the intersection from one side to the other:

We placed our camera kit on one corner to capture both directions of traffic. The overhead image and map below demonstrates the coverage, distances and pixels per foot at different positions.

Then we analyzed a series of scenes to see how performance varied across the cameras. We digitally zoomed each camera to the same level to see the differences. See an example scene comparison from our parking lot test.

We conducted our analysis across 13 scenes. They are:

• Midday Comparison By Distance / HFoV
• Night Comparison by Distance / HFoV
• Midday Intersection - Vehicle (Far)
• Midday Intersection - Vehicle (Mid)
• Midday Intersection - Vehicle (Near)
• Midday Intersection - Person (Far)
• Midday Intersection - Person (Near)
• Night Intersection - Vehicle  (Far)
• Night Intersection - Vehicle (Mid)
• Night Intersection - Vehicle (Near)
• Night Intersection - Person (Far)
• Night Intersection - Person (Near)
• Midday Half Intersection Analysis

Inside, we dig into and provide recommendations on each one, sharing our findings from the test.