An image gradient is a(or the most) directional change in the intensity or color in an image. * Canny edge detector uses image gradient for edge detection. The gradient of a two-variable function (here the image intensity function) at each image point is a 2D vector with the components givenContinue Reading
Representing points in a homogeneous way on a projective plane is done for easier way to write down a coordinate system of a point in infinity, and also it’s very convenient way forming lines from points in algebric formulation. Viewing a point on an image from a distance(1 distance awayContinue Reading
Is the regression line good? We need to check the mean and std of x and the mean and std y. r = ((1/n)(∑xi-x¯)/sx) (∑yi -ȳ)/sy = ((1/n)(∑xi-x¯)/sqrt(xi-x¯/n))(∑yi -ȳ)/sqrt(∑yi -ȳ/n) r= (1/n-1) ∑Zscore(xi)Zscore(yi) [-1,1] is the range/interval of the residual/correlation coefficient when r=-1 or r=1 represent that each point willContinue Reading
Measure distance/length and position from a single photo. By vanishing points: Vanishing points lie in a particular line called the horizon. Connecting these vanishing points gives you information whether the camera is tilted or not with respect to the ground floor, and also an idea about where the camera centerContinue Reading
Regression is estimation(correlation) – of the independent variable with the dependent variable.(We can make a scatter plot whenever you have data that relates two values together). We need an equation – which models the data for y(dependent) for any x(independent), that is, the correlation between them. If the data pointsContinue Reading
Yair Shinar for Clarity and Solutions