Question

Which of the following method is NOT used for compact storage of raster GIS data?

• A. \( \text{Chain code} \)
• B. \( \text{Run-length code} \)
• C. \( \text{Quadtree} \)
• D. \( \text{Decision-tree} \)

Hint:

Think of raster compression methods as reducing redundancy in the grid of pixel values. Decision trees serve a different purpose in data analysis.

Answer 1

The Correct Option is D

\begin{itemize} \item Run-length encoding is a method for compressing raster data by storing sequences of identical pixel values (runs) as a single value and its count. \item Quadtrees are hierarchical data structures used to partition a two-dimensional space by recursively subdividing it into four equal-sized quadrants, efficient for storing and querying spatial data, including raster. \item Chain codes are primarily used to represent vector data, describing the boundary of an area as a sequence of connected line segments and their directions. \item Decision trees are tree-like structures used for classification and regression, not typically for the compact storage of raster GIS data itself. \end{itemize} Therefore, Decision-tree is NOT a standard method for compact raster data storage.