input

Documentation

Index

• Variables
• func CopyBuffers(dst, src [][]Sample)
• func DefaultBackend() string
• func EnsureBufferLen(cfg SessionConfig, buf [][]Sample) bool
• func GetAllBackendNames() []string
• func HasBackend(name string) bool
• func MakeBuffers(channels, samples int) [][]Sample
• func RegisterBackend(name string, b Backend)
• type Backend
  • func FindBackend(name string) Backend
  • func InitBackend(bknd string) (Backend, error)
• type Device
  • func GetDevice(backend Backend, device string) (Device, error)
• type NamedBackend
• type Processor
• type Sample
• type Session
• type SessionConfig

Variables

var Backends []NamedBackend

Functions

func CopyBuffers

func CopyBuffers(dst, src [][]Sample)

CopyBuffers deep copies src to dst. It does NOT do length check.

func DefaultBackend

func DefaultBackend() string

Get the default backend depending on runtime.GOOS

func EnsureBufferLen

func EnsureBufferLen(cfg SessionConfig, buf [][]Sample) bool

EnsureBufferLen ensures that the given buffer has matching sizes with the needed parameters from SessionConfig. It is effectively a bound check.

func GetAllBackendNames

func GetAllBackendNames() []string

Get all installed backend names.

func HasBackend

func HasBackend(name string) bool

func MakeBuffers

func MakeBuffers(channels, samples int) [][]Sample

MakeBuffer allocates a slice of sample buffers.

func RegisterBackend

func RegisterBackend(name string, b Backend)

RegisterBackend registers a backend globally. This function is not thread-safe, and most packages should call it on init().

Types

type Backend

type Backend interface {
	// Init should do nothing if called more than once.
	Init() error
	Close() error

	Devices() ([]Device, error)
	DefaultDevice() (Device, error)
	Start(SessionConfig) (Session, error)
}

func FindBackend

func FindBackend(name string) Backend

FindBackend is a helper function that finds a backend. It returns nil if the backend is not found.

func InitBackend

func InitBackend(bknd string) (Backend, error)

type Device

type Device interface {
	// String returns the device name.
	String() string
}

func GetDevice

func GetDevice(backend Backend, device string) (Device, error)

type NamedBackend

type NamedBackend struct {
	Name string
	Backend
}

type Processor

type Processor interface {
	Process()
}

Processor is called by Session everytime the buffer is full. Session may call this on another goroutine; the implementation must handle synchronization. It must also handle buffer swapping or copying if it wants to synchronize it away.

type Sample

type Sample = float64

type Session

type Session interface {
	// Start blocks until either the context is canceled or an error is
	// encountered.
	Start(context.Context, [][]Sample, chan bool, *sync.Mutex) error
}

Session is the interface for an input session. Its task is to call the processor everytime the buffer is full using the parameters given in SessionConfig.

type SessionConfig

type SessionConfig struct {
	Device     Device
	FrameSize  int     // number of channels per frame
	SampleSize int     // number of frames per buffer write
	SampleRate float64 // sample rate
}