使用 Accelerate 框架将单精度浮点值转换为 Int 16

Question

如何借助 Accelerate 框架将单精度浮点数转换为 int 16。

Int16 到浮点数：

import Accelerate

let rr: [Int16] = [ 18, 21, 41, 42, 48, 50, 55, 90]

var float = [Float](repeating: 0, count: rr.count)

vDSP_vflt16(rr, 1, &float, 1, vDSP_Length(rr.count))

现在我要尝试将它从 Float 恢复为 Int16 吗？

Answer 1

你可以使用 vDSP_vfix16 :

var ints = [Int16](repeating: 0, count: rr.count)

vDSP_vfix16(float, 1, &ints, 1, vDSP_Length(float.count))

print(ints)

// [18, 21, 41, 42, 48, 50, 55, 90]

vDSP_vfix16 向 0 舍入。您可以在 "Single-Vector Floating Point to 16-Bit Integer Conversion" 部分 here.[= 中找到使用其他舍入规则的其他函数14=]

Answer 2

vDSP Swift 覆盖层中还有 floatingPointToInteger：

let floats: [Float] = [ 18, 21, 41, 42, 48, 50, 55, 90]

let ints = vDSP.floatingPointToInteger(floats,
                                       integerType: Int16.self,
                                       rounding: .towardNearestInteger)

print(ints) // Prints "[18, 21, 41, 42, 48, 50, 55, 90]"

使用 Accelerate 框架将单精度浮点值转换为 Int 16

Convert single-precision, floating-point value to Int 16 using Accelerate framework

ios

swift

accelerate-framework

vdsp