Object-based classification in remote sensing

Object-based classification in remote sensing is a method of image analysis that involves grouping pixels into distinct objects or features based on their characteristics, such as shape, size, and texture. The goal of object-based classification is to identify and map specific features or land covers, such as buildings, roads, or vegetation types, within an image.

The process of object-based classification typically involves several steps:

Segmentation: The image is divided into smaller, homogeneous regions or segments, based on characteristics such as color, texture, and shape.

Feature extraction: Characteristics such as size, shape, and texture are extracted from the segments, creating a set of features that can be used to differentiate one segment from another.

Classification: The segments are then classified into different classes or categories, such as buildings, roads, or vegetation, based on the extracted features.

Post-classification: The classified segments are then combined to create a final map of the study area, where each object is labeled with its corresponding class.

An example of object-based classification in remote sensing is the use of high-resolution satellite images to map and monitor urban areas. In this application, the image is first segmented into smaller regions, such as buildings, roads, and parks. Then, features such as size, shape, and texture are extracted from each segment. Finally, the segments are classified into different classes, such as residential, commercial, or industrial areas.

In summary, Object-based classification in remote sensing is a method of image analysis that involves grouping pixels into distinct objects or features based on their characteristics, such as shape, size, and texture, with the goal of identifying and mapping specific features or land covers within an image. The process typically involves segmentation, feature extraction, classification, and post-classification steps.

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