# init(device:kernelWidth:kernelHeight:weights:) Initialize a downwards n-tap image pyramid with a custom filter kernel and device. ``` init(device: any MTLDevice, kernelWidth: Int, kernelHeight: Int, weights kernelWeights: UnsafePointer) ``` ## Parameters `device` The device the filter will run on. `kernelWidth` The width of the filter kernel. `kernelHeight` The height of the filter kernel. `kernelWeights` A pointer to an array of `kernelWidth*kernelHeight` values to be used as the kernel. These values are in row-major order. ## Return Value A valid [`MPSImagePyramid`](/documentation/MetalPerformanceShaders/MPSImagePyramid) object or `nil`, if failure. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)