Histogram Calculation

Overview

// classes

class cv::cuda::CLAHE;

// global functions

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

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

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

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

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

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

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

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

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

Detailed Documentation

Global Functions

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

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

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

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

Equalizes the histogram of a grayscale image.

Parameters:

src Source image with CV_8UC1 type.
dst Destination image.
stream Stream for the asynchronous version.

See also:

equalizeHist

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

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

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

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

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

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

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