Image Processing

[adiDavid]

Hello
I was given this question on a job interview and think I really messed up. I was wondering how others would go about it so I could learn from this expirience-
You have one image from a surveillance video located at an airport which includes line of people waiting for Check-in. You have to asses if the line is big/crowded and therefore additional clerks are necessary. You can assume anything that may help your answer. What would you do?
I told them I would try to
1)segment the area containing people from the rest by edge detection
2) use assumptions on body contour such as relative height/width to denoise unwanted edges
3)use color knowledges- but then they asked how to do that and I didn't know

Thanks in advance
Adi

[snibgo]

I think they just wanted you to explain what could be done, so you could demonstrate your knowledge.

You could talk about how to recognise the presence of a person, perhaps even a face, and count them. You could say the physical length of the queue may be more important than actually counting people, so cropping the shot to the floor area would give an easy estimate. You might mention that the problem is much simpler if you have two images where one contains no people, or two frames from the video.