This application computes edge features on every pixel of the input image selected channel
This application computes edge features on a selected channel of the input.It uses different filters such as gradient, Sobel and Touzi
This application has several output images and supports “multi-writing”. Instead of computing and writing each image independently, the streamed image blocks are written in a synchronous way for each output. The output images will be computed strip by strip, using the available RAM to compute the strip size, and a user defined streaming mode can be specified using the streaming extended filenames (type, mode and value). Note that multi-writing can be disabled using the multi-write extended filename option: &multiwrite=false, in this case the output images will be written one by one. Note that multi-writing is not supported for MPI writers.
-in image Mandatory
The input image on which the features are computed.
Feature Output Image
-out image [dtype] Mandatory
Output image containing the edge features.
-channel int Default value: 1
The selected channel index
-filter [gradient|sobel|touzi] Default value: gradient
Choice of edge feature
This filter computes the gradient magnitude of the image at each pixel.
This filter uses the Sobel operator to calculate the image gradient and then finds the magnitude of this gradient vector.
This filter is more suited to radar images. It has a spatial parameter to avoid speckle noise perturbations. The larger the radius is, the less sensitive the filter is to the speckle noise, but micro edge will be missed.
From the command-line:
otbcli_EdgeExtraction -in qb_RoadExtract.tif -channel 1 -out Edges.tif
import otbApplication app = otbApplication.Registry.CreateApplication("EdgeExtraction") app.SetParameterString("in", "qb_RoadExtract.tif") app.SetParameterInt("channel", 1) app.SetParameterString("out", "Edges.tif") app.ExecuteAndWriteOutput()