Implement RANSAC for robust line fitting to 2D points with outliers. This task involves using the RANSAC algorithm to estimate the parameters of a line that best fits a set of 2D points, some of which may be outliers.
The RANSAC algorithm is a robust estimation technique used to fit models to data with outliers. It works by randomly selecting a minimum number of samples, fitting a model to these samples, and then counting the number of inliers, which are points that are within a certain threshold of the model. The process is repeated for a specified number of iterations, and the model with the most inliers is kept as the best fit. In the case of line fitting, the line can be represented by the equation ax+by+c=0, where a2+b2=1. The distance from a point (x0,y0) to the line is given by d=∣ax0+by0+c∣.
Here are the steps to follow:
This technique is widely used in computer vision applications, such as image processing and feature detection.
points = [[0,0], [1,1], [2,2], [3,3], [10,0]] # Last is outlier threshold = 0.1 n_iterations = 100
{'line': [0.707, -0.707, 0], 'inliers': 4}Points [0,0], [1,1], [2,2], [3,3] lie on y=x line. Line equation: x - y = 0, normalized: 0.707x - 0.707y = 0
Point [10,0] is far from this line (outlier).
RANSAC finds the line with 4 inliers, ignoring the outlier.