vDSP

Use these functions for digital signal processing.

Overview

This section describes the C and Swift APIs for performing common routines on a single vector in vDSP. These functions perform tasks such as finding the absolute value of a vector, compressing the values of a vector, or converting between single and double precision vectors.

This document describes the vDSP portion of the Accelerate framework. The vDSP header provides a number of functions related to digital signal processing, including:

  • Vector and matrix arithmetic

  • Fourier transforms

  • Convolution, correlation, and window generation

  • Biquadratic filtering

For an overview that describes how to use these routines, read vDSP Programming Guide.

Topics

Vector Generation, Filling, and Clearing

Vector Generation
Vector Clear and Fill Functions

Vector Reduction

Vector Extrema Calculation
Vector Average Calculation
Vector Summation

Vector Geometry Functions

Vector-to-Vector Distance and Pythagorean Computation
Dot Product Calculation

Vector-Scalar Arithmetic

Basic Arithmetic Functions
Multiply-Add Functions
Multiply-Subtract Functions

Vector-Vector Arithmetic

Real Basic Arithmetic
Complex Basic Arithmetic
Integer Arithmetic
Linear Averaging Functions
Polynomial Evaluation

Vector Operations

Compression and Gathering Functions
Copying, Element Swapping, and Merging Functions
Reversing and Sorting Functions

Vector Interpolation

Linear Interpolation Functions
Quadratic Interpolation Functions

Vector Filtering

Single-Channel Biquadratic IIR Filters
Multichannel Biquadratic IIR Filters
Finite Impulse Response Filters
Recursive Filters

Vector Conversion Functions

Conversion to Decibel Equivalents
Type Conversion
Complex Vector Conversion
Polar-Rectangular Conversion

Single-Vector Arithmetic Functions

Absolute and Negation Functions
Integration Functions
Clipping, Limit, and Threshold Operations
Normalization Functions
Phase Computation Functions
Complex Conjugation Functions
Vector Squaring Functions
Fractional Part Extraction
Zero Crossing Search

Single-Vector Sliding-Window Operations

Sliding-Window Summation Functions
Sliding-Window Maxima Functions

Vector-to-Vector Spectra and Coherence Computation

Autospectrum Computation
Cross-Spectrum Computation
Coherence Function Computation

Vector-to-Vector Extrema Functions

Vector-to-Vector Minima and Maxima
Extrema Finding Functions

Matrix Operations

Multiplication
Transposition
Matrix and Submatrix Copying Functions

Vector and Matrix Correlation and Convolution

1D Correlation and Convolution
2D Convolution

Vector and Matrix Fourier Transforms

Fast Fourier Transforms
Discrete Fourier Transforms

Data Types

typealias vDSP_Length

Used for numbers of elements in arrays and indices of elements in arrays. It is also used for the base-two logarithm of numbers of elements.

typealias vDSP_Stride

Used to hold differences between indices of elements, including the lengths of strides.

struct DSPComplex

Used to hold a complex value.

struct DSPSplitComplex

A structure that represents a single-precision complex number with the real and imaginary parts stored in separate arrays.

struct DSPDoubleComplex

Used to hold a double-precision complex value.

struct DSPDoubleSplitComplex

A structure that represents a double-precision complex number with the real and imaginary parts stored in separate arrays.

Constants

vDSP Compile-Time Version Information

The version of vDSP (at compile time).