Histogram Calculation#

Detailed Description#

Classes#

Name

Description

class cv::cuda::CLAHE

Base class for Contrast Limited Adaptive Histogram Equalization. : View details

Function Documentation#

calcHist()#

void cv::cuda::calcHist(
InputArray src,
InputArray mask,
OutputArray hist,
Stream & stream = Stream::Null() )

#include <opencv2/cudaimgproc.hpp>

Calculates histogram for one channel 8-bit image confined in given mask.

Parameters

  • src — Source image with CV_8UC1 type.

  • hist — Destination histogram with one row, 256 columns, and the CV_32SC1 type.

  • mask — A mask image same size as src and of type CV_8UC1.

  • stream — Stream for the asynchronous version.

calcHist()#

void cv::cuda::calcHist(
InputArray src,
OutputArray hist,
Stream & stream = Stream::Null() )

#include <opencv2/cudaimgproc.hpp>

Calculates histogram for one channel 8-bit image.

Parameters

  • src — Source image with CV_8UC1 type.

  • hist — Destination histogram with one row, 256 columns, and the CV_32SC1 type.

  • stream — Stream for the asynchronous version.

createCLAHE()#

Ptr< cuda::CLAHE > cv::cuda::createCLAHE(
double clipLimit = 40.0,
Size tileGridSize = Size(8, 8) )

#include <opencv2/cudaimgproc.hpp>

Creates implementation for cuda::CLAHE .

Parameters

  • clipLimit — Threshold for contrast limiting.

  • tileGridSize — Size of grid for histogram equalization. Input image will be divided into equally sized rectangular tiles. tileGridSize defines the number of tiles in row and column.

equalizeHist()#

void cv::cuda::equalizeHist(
InputArray src,
OutputArray dst,
Stream & stream = Stream::Null() )

#include <opencv2/cudaimgproc.hpp>

Equalizes the histogram of a grayscale image.

See also

equalizeHist

Parameters

  • src — Source image with CV_8UC1 type.

  • dst — Destination image.

  • stream — Stream for the asynchronous version.

evenLevels()#

void cv::cuda::evenLevels(
OutputArray levels,
int nLevels,
int lowerLevel,
int upperLevel,
Stream & stream = Stream::Null() )

#include <opencv2/cudaimgproc.hpp>

Computes levels with even distribution.

Parameters

  • levels — Destination array. levels has 1 row, nLevels columns, and the CV_32SC1 type.

  • nLevels — Number of computed levels. nLevels must be at least 2.

  • lowerLevel — Lower boundary value of the lowest level.

  • upperLevel — Upper boundary value of the greatest level.

  • stream — Stream for the asynchronous version.

histEven()#

void cv::cuda::histEven(
InputArray src,
GpuMat[4] hist,
int[4] histSize,
int[4] lowerLevel,
int[4] upperLevel,
Stream & stream = Stream::Null() )

#include <opencv2/cudaimgproc.hpp>

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

histEven()#

void cv::cuda::histEven(
InputArray src,
OutputArray hist,
int histSize,
int lowerLevel,
int upperLevel,
Stream & stream = Stream::Null() )

#include <opencv2/cudaimgproc.hpp>

Calculates a histogram with evenly distributed bins.

Parameters

  • src — Source image. CV_8U, CV_16U, or CV_16S depth and 1 or 4 channels are supported. For a four-channel image, all channels are processed separately.

  • hist — Destination histogram with one row, histSize columns, and the CV_32S type.

  • histSize — Size of the histogram.

  • lowerLevel — Lower boundary of lowest-level bin.

  • upperLevel — Upper boundary of highest-level bin.

  • stream — Stream for the asynchronous version.

histRange()#

void cv::cuda::histRange(
InputArray src,
GpuMat[4] hist,
const GpuMat[4] levels,
Stream & stream = Stream::Null() )

#include <opencv2/cudaimgproc.hpp>

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

histRange()#

void cv::cuda::histRange(
InputArray src,
OutputArray hist,
InputArray levels,
Stream & stream = Stream::Null() )

#include <opencv2/cudaimgproc.hpp>

Calculates a histogram with bins determined by the levels array.

Parameters

  • src — Source image. CV_8U , CV_16U , or CV_16S depth and 1 or 4 channels are supported. For a four-channel image, all channels are processed separately.

  • hist — Destination histogram with one row, (levels.cols-1) columns, and the CV_32SC1 type.

  • levels — Number of levels in the histogram.

  • stream — Stream for the asynchronous version.