---
title: "vImageConvert_RGB565toRGBA8888(_:_:_:_:)"
framework: accelerate
role: symbol
role_heading: Function
path: "accelerate/vimageconvert_rgb565torgba8888(_:_:_:_:)"
---

# vImageConvert_RGB565toRGBA8888(_:_:_:_:)

Combines an RGB565 3-channel RGB buffer and a constant alpha value to produce an 8-bit-per-channel, 4-channel RGBA buffer.

## Declaration

```swift
func vImageConvert_RGB565toRGBA8888(_ alpha: Pixel_8, _ src: UnsafePointer<vImage_Buffer>, _ dest: UnsafePointer<vImage_Buffer>, _ flags: vImage_Flags) -> vImage_Error
```

## Parameters

- `alpha`: The constant destination alpha value.
- `src`: The source vImage buffer.
- `dest`: A pointer to the destination vImage buffer structure. You’re responsible for filling out the doc://com.apple.accelerate/documentation/Accelerate/vImage_Buffer/height, doc://com.apple.accelerate/documentation/Accelerate/vImage_Buffer/width, and doc://com.apple.accelerate/documentation/Accelerate/vImage_Buffer/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, deallocate the memory to prevent memory leaks.
- `flags`: The options to use when performing the operation. If your code implements its own tiling or its own multithreading, pass doc://com.apple.accelerate/documentation/Accelerate/kvImageDoNotTile; otherwise, pass doc://com.apple.accelerate/documentation/Accelerate/kvImageNoFlags.

## Return Value

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

## Discussion

Discussion The function uses the following calculation to perform the conversion:     Pixel8 alpha = alpha     Pixel8 red   = (5bitRedChannel   * 255 + 15) / 31     Pixel8 green = (6bitGreenChannel * 255 + 31) / 63     Pixel8 blue  = (5bitBlueChannel  * 255 + 15) / 31

## See Also

### Conversion from RGB565 16-bit-per-channel, 3-channel interleaved buffers

- [vImageConvert_RGB565toARGB8888(_:_:_:_:)](accelerate/vimageconvert_rgb565toargb8888(_:_:_:_:).md)
- [vImageConvert_RGB565toBGRA8888(_:_:_:_:)](accelerate/vimageconvert_rgb565tobgra8888(_:_:_:_:).md)
- [vImageConvert_RGB565toARGB1555(_:_:_:_:)](accelerate/vimageconvert_rgb565toargb1555(_:_:_:_:).md)
- [vImageConvert_RGB565toRGBA5551(_:_:_:_:)](accelerate/vimageconvert_rgb565torgba5551(_:_:_:_:).md)