localMax

localMax ( integer Input, integer Output , integer Probe )

Use this function to find local maxima of intensity in an image or selection. The function works by extracting only those target pixels whose values are greater or equal to the values of all the pixels in their neighborhood. The size and shape of the neighborhood pattern is selected with the Probe parameter.

Parameters

Input

An integer between 0 and 116 specifying the input image frame number. A value of 0 represents the DMA memory buffer of the video device. Values in the range of 100-116 correspond to hidden frames.

Output

An integer between 1 and 116 specifying the output image frame number. Values in the range of 100-116 correspond to hidden frames.

Probe

An enumerated integer that describes the shape and size of the kernel used in the operation. The value is determined as a combination of four basic shapes constructed of 3 pixels:

PR_VBAR=1 – vertical bar

PR_BKSLASH=2 – diagonal bar (top left – bottom right)

PR_HBAR=4 – horizontal bar

PR_FWSLASH=8 –diagonal bar (bottom left – top right)

The following frequently used shapes represent combinations of the basic shapes:

PR_CROSS=5 – cross 3x3

PR_DCROSS=10 – diagonal cross 3x3

PR_SQUARE=15 – square 3x3

You can also assign one kernel of size 5x5:

PR_CIRCLE=16 – circle 5x5

Error flags

ERR_OK

The flag set if successful.

ERR_FAILED

The flag set if failed.

Example

This set of statements extracts local maxima from a sample image:

setCurDir ("samples")

loadIm (1,"sample14.iwd")

localMax(1,2)