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jit.sobel

Sobel and Prewitt gradient edge detector

Description

The jit.sobel object offers two similar gradient edge detection implementations, Sobel and Prewitt. These edge detectors use 3x3 convolution kernels to compute a 2-dimensional spatial gradient of an incoming matrix, brightening features with "high spatial frequency" -- a large amount of change from cell to cell -- and darkening features with less change. The Sobel detector is fairly good at detecting edges in all directions, while the Prewitt is more biased toward edges running vertically and horizontally along the matrix frame.

Matrix Operator

matrix inputs:1, matrix outputs:1
Name IOProc Planelink Typelink Dimlink Plane Dim Type
out n/a 1 1 1 1 1 char long float32 float64

Information for Jitter Matrix Operator (MOP) messages and attributes to this object

Attributes

Name Type g/s Description
mode int The detection mode. (default = 0 (Sobel))
0 = Sobel
1 = Prewitt
thresh float The threshold below which matrix values are set to 0. (default = 0.)

Information for box attributes common to all objects

Examples

See Also

Name Description
jit.brass Emboss image
jit.qt.effect QuickTime Effects for Jitter matrices
jit.robcross Robert's Cross edge detection
Tutorial 25: Tracking the Position of a Color in a Movie Tutorial 25: Tracking the Position of a Color in a Movie