RSGISLib Image Change Detection Module

The changedetect module provides tools for change detection using remotely sensed imagery.

Image Pixel Change Detection

rsgislib.changedetect.pxl_outlier_chng.find_class_outliers(pyod_obj, img, img_mask, out_lbls_img, out_scores_img=None, img_mask_val=1, img_bands=None, gdalformat='KEA')

This function uses the pyod (https://github.com/yzhao062/pyod) library to find outliers within a class. It is assumed that the input images are from a different date than the mask (classification) and therefore the outliners will related to class changes.

Parameters

  • pyod_obj – an instance of a pyod.models (e.g., pyod.models.knn.KNN) pass parameters to the constructor

  • img – input image used for analysis

  • img_mask – input image mask use to define the region of interest.

  • out_lbls_img – output image with pixel over of 1 for within mask but not outlier and 2 for in mask and outlier.

  • out_scores_img – output image (optional, None and won’t be provided; Default None) providing the probability of each pixel being an outlier

  • img_mask_val – the pixel value within the mask image for the class of interest. (Default 1)

  • img_bands – the image bands to be used for the analysis. If None then all used (Default: None)

  • gdalformat – file format for the output image(s). Default KEA.