computes the accumulator matrix used by the Hough lines detector More...

IPSDKIPLFEATUREDETECTION_API image::ImagePtr	ipsdk::imaproc::fd::houghLines2dImg (const image::ImageConstPtr &pInGreyImg2d)
	wrapper function for computation of accumulator matrix of regular Hough lines detector detector, from a grey-level input image More...

IPSDKIPLFEATUREDETECTION_API image::ImagePtr	ipsdk::imaproc::fd::houghLines2dImg (const image::ImageConstPtr &pInGreyImg2d, const ipsdk::imaproc::attr::HoughLinesImgParamsConstPtr &pHoughLinesImgParams)
	wrapper function for computation of accumulator matrix of regular Hough lines detector detector, from a grey-level input image More...

Detailed Description

computes the accumulator matrix used by the Hough lines detector

This algorithm computes, from a grey levels 2d image, the accumulation matrix used to detect straight lines in the input image, using Hough transform.

See HoughLines2d for more information

Attributes description

Attribute description for algorithm :

Name	ToolTip	Default Initializer
ipsdk::imaproc::attr::InGreyImg2d	[Input] 2d grey levels image	X
ipsdk::imaproc::attr::InOptHoughLinesImgParams	[Input Optional] Parameters for Hough lines detection algorithm	X
ipsdk::imaproc::attr::OutImg	[Output] image for processing operation	customOutput (_pOutImg, outputHoughLines2dImg(_pInGreyImg2d,_pInOptHoughLinesImgParams))

Global Rule description

Global rule description for algorithm :
ipsdk::imaproc::customImageProperty (_pOutImg,
ipsdk::imaproc::fd::houghLines2dCheckOutImgSzXEquals (_pInGreyImg2d,_pInOptHoughLinesImgParams)) &&
ipsdk::imaproc::customImageProperty (_pOutImg,
ipsdk::imaproc::fd::houghLines2dCheckOutImgSzYEquals (_pInGreyImg2d,_pInOptHoughLinesImgParams)) &&
ipsdk::imaproc::customImageProperty (_pOutImg,
ipsdk::imaproc::fd::houghLines2dCheckOutImgBufferType (_pInGreyImg2d)) &&
ipsdk::imaproc::matchSize (eMatchImageSizeType::eMIST_T,_pInGreyImg2d,_pOutImg) &&
ipsdk::imaproc::matchVolumeGeometryType (_pInGreyImg2d,_pOutImg) &&
ipsdk::imaproc::matchColorGeometryType (_pInGreyImg2d,_pOutImg) &&
ipsdk::imaproc::noInSitu (_pInGreyImg2d,_pOutImg)

Example of Python code :

Example imports

import PyIPSDK
import PyIPSDK.IPSDKIPLFeatureDetection as fd
import PyIPSDK.IPSDKIPLFiltering as filter

Code Example

    # opening of input image
    inImg = PyIPSDK.loadTiffImageFile(inputImgPath)
    
    # Initialize parameters for Hough lines accumulation matrix construction:
    # - step for rho = 1
    rhoStep = 2.0
    
    # - range of 15 evenly spaced orientations between pi/2 and 3.pi/4 radians
    thetaRange = PyIPSDK.createEvenlySpacedRange(math.pi/2, 3*math.pi/4, 15)
        
    # only accumulate pixels of input image with intensity greater than  210
    intensityThreshold = 210.0
    
    imgParams = PyIPSDK.createHoughLinesImgParams(
        rhoStep, thetaRange, intensityThreshold)
    # hough circle detection computation
    outImg = fd.houghLines2dImg(inImg, imgParams)

Example of C++ code :

Example informations

Associated library

IPSDKIPLFeatureDetection

Header file

#include <IPSDKIPL/IPSDKIPLFeatureDetection/Processor/HoughLines2dImg/HoughLines2dImg.h>

Code Example

    ImageConstPtr pInImg = loadTiffImageFile(inImgPath);
    // Initialize parameters for Hough lines accumulation matrix construction:
    // - step for rho = 1
    const ipReal64 rhoStep = 1.0;
    // - range of 15 evenly spaced orientations between pi/2 and 3.pi/4 radians
    const EvenlySpacedRange& thetaRange = *createEvenlySpacedRange(
        M_PI / 2, 3 * M_PI / 4, 15);
    // only accumulate pixels of input image with intensity greater than  10
    const ipReal32 intensityThreshold = 10.0f;
    const HoughLinesImgParamsConstPtr pInHoughImgPrms = createHoughLinesImgParams(
        rhoStep, thetaRange, intensityThreshold);
    // launch Hough lines detection algorithm
    const ImageConstPtr pOutImg = houghLines2dImg(pInImg, pInHoughImgPrms);

See also: HoughLines2dImgLvl1; HoughLines2dImgLvl2; HoughLines2dImgLvl3

Function Documentation

◆ houghLines2dImg() [1/2]

IPSDKIPLFEATUREDETECTION_API image::ImagePtr ipsdk::imaproc::fd::houghLines2dImg ( const image::ImageConstPtr & pInGreyImg2d )

wrapper function for computation of accumulator matrix of regular Hough lines detector detector, from a grey-level input image

Exceptions

ipsdk::processor::IPSDKBaseProcessingException on failure

◆ houghLines2dImg() [2/2]

IPSDKIPLFEATUREDETECTION_API image::ImagePtr ipsdk::imaproc::fd::houghLines2dImg	(	const image::ImageConstPtr &	pInGreyImg2d,
		const ipsdk::imaproc::attr::HoughLinesImgParamsConstPtr &	pHoughLinesImgParams
	)

wrapper function for computation of accumulator matrix of regular Hough lines detector detector, from a grey-level input image

Exceptions

ipsdk::processor::IPSDKBaseProcessingException on failure