SauvolaThreshold

Apply Sauvola local threshold to source image.

Syntax

Definition:

HRESULT SauvolaThreshold(
    HRESULT            hrPrev,
    ITcVnImage*        ipSrcImage,
    ITcVnImage*&       pipDestImage,
    ULONG              nBlockSize,
    double             fParamK,
    double             fMaxSigma,
    ETcVnThresholdType eThresholdType
)

Parameters

Name

Type

Description

hrPrev

HRESULT

HRESULT indicating the result of previous operations (If SUCCEEDED(hrPrev) equals false, no operation is executed.)

ipSrcImage

ITcVnImage*

Source image (USINT, UINT, INT, REAL, or LREAL, 1 channel)

pipDestImage

ITcVnImage*&

Destination image (An appropriate single channel destination image will be created if required.))

nBlockSize

ULONG

Size of the pixel neighborhood to calculate the local threshold (3, 5, 7, ...)

fParamK

double

parameter K which takes positive values in range (0,1). Recommended are K in range [0.2, 0.5]

fMaxSigma

double

Maximum value of the standard deviation, required to be strictly positive. (fMaxSigma = 128 for a grayscale document).

eThresholdType

ETcVnThresholdType

Threshold type to be applied. Supported are TCVN_TT_BINARY and TCVN_TT_BINARY_INV.

 Return value

HRESULT

Required License

TC3 Vision Base

System Requirements

Development environment

Target platform

PLC libraries to include

TwinCAT V3.1.4024.59 or later

PC or CX (x64) with PL50, e.g. Intel 4-core Atom CPU

Tc3_Vision