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Case Study: How to Evaluate Property Tax using Drone Photogrammetric Images?

Objective: Land and Revenue department of Bihar Government responsible for Tax and Revenue collection in the state of Bihar, India, was struggling with efficient property tax collection; considering the poor evaluation techniques and weaker effect of the existing system.


Photo Credits: Archinect Features

Problems Faced by Government

  1. For effective property tax evaluation District Magistrate needs to know the following factors:

Drone Photogrammetry and Property Tax Evaluation

Flow Chart showing Work Progression

Tax Calculation

The Challenge we faced:

Solutions Provided

  1. Detecting Building Footprint from orthomosaic aerial image.
  2. Vectorized output of building’s boundary Building Foot Prints.
  3. Area and the number of floors*.
  4. Estimated tax collection from the area.

What Impact did the Solution Make?

  1. Quick: The first key metric to understand the increased efficiency is reduced man-hours (time); In the manual digitizing process it took 2 man-days to give qualified output for 5 sq. km, now the same is performed in 2 minutes employing 0.5 man days.
  2. Digitalized data: The raster drone images were digitalized to provide attributes for calculating revenue on the basis of the area and the number of storeys in the building. Digitalizing data is also synonymous to preserving it for future scope.
  3. Better: As the property tax and revenue collection was increased by 2.5x.

Methods Used



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Maitri Dwivedi

I put words to ideas, interested in functional products, consumer psychology, forms of human articulation, design, and art.