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step

System object: visionhdl.ImageFilter
Package: visionhdl

2-D FIR filtering

Description

Note

Starting in R2016b, instead of using the step method to perform the operation defined by the System object™, you can call the object with arguments, as if it were a function. For example, y = step(obj,x) and y = obj(x) perform equivalent operations.

[pixelOut,ctrlOut] = step(filt,pixelIn,ctrlIn) returns the next pixel, pixelOut, of the filtered image resulting from applying the coefficients in the Coefficients property to the image described by the input pixel stream, pixelIn.

[pixelOut,ctrlOut] = step(filt,pixelIn,ctrlIn,coeff) returns the next pixel, pixelOut, of the filtered image resulting from applying the coefficients in the coeff argument to the image described by the input pixel stream, pixelIn. The object samples the values from the coeff argument only at the start of a frame and ignores any changes within a frame. To enable this syntax, set the CoefficientsSource property to 'Input port'.

Note

The System object performs an initialization the first time you call the step method. This initialization locks nontunable properties and input specifications, such as dimensions, complexity, and data type of the input data. If you change a nontunable property or an input specification, the object issues an error. To change nontunable properties or inputs, first call the release method to unlock the object.

Input Arguments

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Specify a visionhdl.ImageFilter System object that you created and configured.

Single pixel, specified as a scalar value.

double and single data types are supported for simulation, but not for HDL code generation.

You can simulate System objects with a multipixel streaming interface, but System objects are not supported for HDL code generation. Use the equivalent blocks to generate HDL code for multipixel algorithms.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | fi

Control signals accompanying input pixel stream, specified as a pixelcontrol structure containing five logical data type signals. The signals describe the validity of the pixel and its location in the frame. For more details, see Pixel Control Structure.

Data Types: struct

Filter coefficients, specified as a matrix. Each dimension of the matrix must have at least 2 elements and no more than 16 elements. The object samples the values from the coeff argument only at the start of a frame and ignores any changes within a frame.

To enable this argument, set the CoefficientsSource property to 'Input port'.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | fi

Output Arguments

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Single filtered pixel, returned as a scalar value.

Configure the data type of the output pixel by using the OutputDataType and CustomOutputDataType properties.

Control signals accompanying output the pixel stream, returned as a pixelcontrol structure containing five logical data type signals. The signals describe the validity of the pixel and its location in the frame. For more details, see Pixel Control Structure.

Data Types: struct

Introduced in R2015a