Function

vImageConvert_Planar16Q12toARGB8888(_:_:_:_:_:_:)

Combines three 16Q12 images into one ARGB8888 image.

Declaration

func vImageConvert_Planar16Q12toARGB8888(_ alpha: UnsafePointer<vImage_Buffer>, _ red: UnsafePointer<vImage_Buffer>, _ green: UnsafePointer<vImage_Buffer>, _ blue: UnsafePointer<vImage_Buffer>, _ dest: UnsafePointer<vImage_Buffer>, _ flags: vImage_Flags) -> vImage_Error

Parameters

alpha

A pointer to a vImage buffer structure that contains the 16Q12 image to use as the alpha channel of the destination image.

red

A pointer to a vImage buffer structure that contains the 16Q12 image to use as the red channel of the destination image.

green

A pointer to a vImage buffer structure that contains the 16Q12 image to use as the green channel of the destination image.

blue

A pointer to a vImage buffer structure that contains the 16Q12 image to use as the blue channel of the destination image.

dest

A pointer to a vImage buffer data structure. You're responsible for filling out the height, width, and rowBytes fields of this structure, and for allocating a data buffer of the appropriate size. On return, the data buffer this structure points to contains the destination image data. When you no longer need the data buffer, you must deallocate the memory.

flags

The options to use when performing the operation. If you plan to perform your own tiling or use multithreading, pass kvImageDoNotTile.

Return Value

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

Discussion

The conversion from 16-bit format with 12 fractional bits to 8-bit float is:

uint8_t dest = clamp(src, 0, 4096)*255 + 2048 >> 12

Source pixel values of 0 are mapped to 0, and source pixel values of 4088 or greater are mapped to 255.

This function doesn't operate in place.

See Also

Converting from Planar Formats

func vImageConvert_FTo16S(UnsafePointer<vImage_Buffer>, UnsafePointer<vImage_Buffer>, Float, Float, vImage_Flags) -> vImage_Error

Converts a PlanarF image into a special format in which each pixel is a 16-bit signed integer.

func vImageConvert_FTo16U(UnsafePointer<vImage_Buffer>, UnsafePointer<vImage_Buffer>, Float, Float, vImage_Flags) -> vImage_Error

Converts a PlanarF image into a special format in which each pixel is a 16-bit unsigned integer.

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