Converts an RGBA8888 image to an RGB565 image with dithering.
- iOS 7.0+
- macOS 10.9+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 2.0+
A pointer to a vImage buffer structure that contains the source image whose data you want to convert.
A pointer to a vImage buffer data structure. You're responsible for filling out the
rowfields 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.
A pointer to a region of memory that vImage can use as a scratch space for storing temporary data.
The options to use when performing the operation. If you plan to perform your own tiling or use multithreading, pass
Image Do Not Tile
The calculation for each pixel is:
This function supports the following dithering options:
Image Convert _Dither Ordered
Precomputed blue noise is added to the image before the values are rounded to the destination format. The offset into the blue noise is randomized per call to avoid visible artifacts if you do your own tiling or call the function on sequential frames of video.
Image Convert _Dither Ordered Reproducible
Precomputed blue noise is added to the image before the values are rounded to the destination format. The offset into the blue noise is the same for every call to allow users to get reproducible results.
This function can operate in place, provided that
src->data == dest->data,
src->row, and the
kv flag is used if