Function

vImageConvert_ARGB8888ToARGB2101010(_:_:_:_:_:_:)

Converts an ARGB8888 format image to an ARGB2101010 format image.

Declaration

func vImageConvert_ARGB8888ToARGB2101010(_ src: UnsafePointer<vImage_Buffer>, _ dest: UnsafePointer<vImage_Buffer>, _ RGB101010RangeMin: Int32, _ RGB101010RangeMax: Int32, _ permuteMap: UnsafePointer<UInt8>!, _ flags: vImage_Flags) -> vImage_Error

Parameters

src

A pointer to the vImage buffer that references 8-bit ARGB interleaved source pixels.

dest

A pointer to the vImage buffer that references 10-bit RGB interleaved destination pixels.

RGB101010RangeMin

The minimum value for the range of 10-bit RGB pixels.

RGB101010RangeMax

The maximum value for the range of 10-bit RGB pixels.

permuteMap

An array of four 8-bit integers with the values 0, 1, 2, and 3, in some order. Each value specifies a channel from the source image that should be copied to that channel in the destination image. 0 denotes the alpha channel, 1 the red channel, 2 the green channel, and 3 the blue channel. 

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

RGB101010RangeMin and RGB101010RangeMax are available for non-full-range pixel values. You can set full-range pixel values as:

 RGB101010RangeMin  = 0;
 RGB101010RangeMax  = 1023;

The per-pixel operation is:

 uint8_t *srcPixel = src.data;
 A8 = srcPixel[permuteMap[0]];
 R8 = srcPixel[permuteMap[1]];
 G8 = srcPixel[permuteMap[2]];
 B8 = srcPixel[permuteMap[3]];
 srcPixel += 4;
 
 int32_t R10, G10, B10;
 int32_t range10 = RGB101010RangeMax - RGB101010RangeMin;
 int32_t rounding = UCHAR_MAX >> 1;
 R10 = ((R8 * range10 + rounding) / UCHAR_MAX) + RGB101010RangeMin;
 G10 = ((G8 * range10 + rounding) / UCHAR_MAX) + RGB101010RangeMin;
 B10 = ((B8 * range10 + rounding) / UCHAR_MAX) + RGB101010RangeMin;
 A10 = ((A10 * 3 + rounding) / UCHAR_MAX);
 
 uint32_t *destPixel = dest.data;
 destPixel[0] = htonl((R10 << 22) | (G10 << 12) | (B10 << 2) | A10);
 destPixel += 1;

See Also

Converting from ARGB Formats

func vImageConvert_ARGBFFFFtoRGBFFF(UnsafePointer<vImage_Buffer>!, UnsafePointer<vImage_Buffer>!, vImage_Flags) -> vImage_Error

Converts a four-channel ARGBFFFF image to a three-channel RGBFFF image by removing the alpha channel.

func vImageConvert_ARGB8888toRGB888(UnsafePointer<vImage_Buffer>, UnsafePointer<vImage_Buffer>, vImage_Flags) -> vImage_Error

Converts a four-channel ARGB8888 image to a three-channel RGB888 image by removing the alpha channel..