Dear friend, 

Can you give us any other measurement? For example: Distance of camera, height of camera, etc.?

What features does your camera supply? Gps, backround recognition..?

Distance of the camera is at orthogonal distance of  8.10 m at the height of 1.44 m  . The height of person is 1.72 m . 

Soory sir but i didn't get by " features from camera"?. no Gps, no background recognition. I am using camera for recording and then my objective is find the height from the video. 

Dear Chandra

you can use the following solution:

1. find angle  between at least point of wall and your camera (as shown in attached figure as 'alpha')

2. find angle between top point of your object(for example human) and camera . it was shown with 'beta'

3. find difference of these two angles. it can be names as 'phi'

4. find  length of opposite line through 'phi' angle. it can be named as : 'H'

5. final height can be found by : camera height  - H

a diagram was attached for detailed information

I hope it may be useful

Regards

Hi

If the scene has a known height of the reference and the background is static, the simple approach are, for example: Approach-1. Known height of the person, or, Approach-2. known height of four white boxes. The actual height of object can be roughly calculated within image by the pixels that occupied by the object.

LSW

Below images are the concept of Approach 1 and 2.