Question

Process of conversion of a pixel (raster) image into point, line and polygon format is called as

• A. Rasterization
• B. Vectorization
• C. Image processing
• D. Clipping

Hint:

In GIS, spatial data is stored in two main models: the raster model (a grid of pixels) and the vector model (points, lines and polygons). Moving data from one model to the other is called data conversion.

Answer 1

The Correct Option is C

Step 1: Know the two GIS data models.
GIS stores spatial data either as a raster (a grid of pixels) or as a vector (points, lines and polygons).

Step 2: Read the question direction.
Here we start from a pixel (raster) image and want to turn it into points, lines and polygons, that is into the vector form.

Step 3: Rule out rasterization.
Rasterization is the opposite, turning vector data into a grid of pixels, so it is not the answer.

Step 4: Rule out the other options.
Image processing means improving or analysing an image, and clipping means cutting data to a boundary, so neither describes this conversion.

Step 5: Name the correct process.
Changing raster pixels into vector points, lines and polygons is called vectorization.

Step 6: State the answer.
The process is vectorization.
\[ \boxed{\text{Vectorization}} \]