Function

vImageHistogramCalculation_ARGB8888(_:_:_:)

Calculates histograms for each channel of an ARGB8888 image.

Declaration

func vImageHistogramCalculation_ARGB8888(_ src: UnsafePointer<vImage_Buffer>, _ histogram: UnsafeMutablePointer<UnsafeMutablePointer<vImagePixelCount>?>, _ flags: vImage_Flags) -> vImage_Error

Parameters

src

A pointer to a vImage buffer structure that contains the source image.

histogram

A pointer to an array of four histograms, one each for alpha, red, green, and blue (in that order). On return, this array will contain the four histograms for the corresponding channels. Each of the four histograms will be an array with 256 elements.

flags

The options to use. Set the kvImageDoNotTile flag if you plan to perform your own tiling or use multithreading.

Return Value

kvImageNoError; otherwise, one of the error codes described in Data Types and Constants.

Discussion

The function calculates the histogram for each channel completely separately from the others. However, size and range values are the same for each of the four histograms.