README
¶
Synopsis
This is a golang ALSA client implementation, without cgo! Unfortunately, doing it without cgo means throwing away many years of compatibility work that has been put into libalsa. So be warned, this library is not likely to work with a lot of the more colorful audio cards out there, and is not likely to work on platforms other than x86_64. (Though, someone has nicely done some work on ARM. Thanks!)
But fear not! Go is fun, and I tried to keep the library on the simple side, so adding in support for what your audio card needs might actually be just a nice afternoon of programming. The hardest part for me was just trying to understand all of the alsa terminology.
For a simple example of synthesized playback, the beep command will produce a sine wave for a few seconds on each detected ALSA output:
go get github.com/yobert/alsa/cmd/beep
$GOPATH/beep
And for recording from a microphone into a WAV file:
go get github.com/yobert/alsa/cmd/record
$GOPATH/record
This example does recording and playback, but it's got a really buggy ring buffer going on:
go get github.com/yobert/alsa/cmd/echoback
$GOPATH/echoback
Disclaimer
This module makes syscalls with pointers to memory buffers that are in garbage collectable memory. I have a feeling this isn't safe, but it hasn't crashed on me yet.
Contributors
Thanks so much for the help! Thanks! See AUTHORS for a list. Pull requests welcome from anybody, regardless of skill level.
See Also
You may be interested in https://github.com/jfreymuth/pulse which is a lot less likely to crash and will probably work with your sound card.
Documentation
¶
Index ¶
- Constants
- func CloseCards(cards []*Card)
- type AccessType
- type Buffer
- type BufferFormat
- type Card
- type Device
- func (device *Device) BufferFormat() BufferFormat
- func (device *Device) BytesPerFrame() int
- func (device *Device) Close()
- func (device *Device) Debug(v bool)
- func (device *Device) NegotiateBufferSize(buffer_sizes ...int) (int, error)
- func (device *Device) NegotiateChannels(channels ...int) (int, error)
- func (device *Device) NegotiateFormat(formats ...FormatType) (FormatType, error)
- func (device *Device) NegotiatePeriodSize(period_sizes ...int) (int, error)
- func (device *Device) NegotiateRate(rates ...int) (int, error)
- func (device *Device) NewBufferDuration(d time.Duration) Buffer
- func (device *Device) NewBufferSeconds(seconds int) Buffer
- func (device *Device) Open() error
- func (device *Device) Prepare() error
- func (device *Device) Read(buf []byte) error
- func (device Device) String() string
- func (device *Device) Write(buf []byte, frames int) error
- type DeviceType
- type Flags
- type FormatType
- type SubformatType
Constants ¶
const ( StandardSubformat SubformatType = iota SubformatTypeFirst = StandardSubformat SubformatTypeLast = StandardSubformat )
Variables ¶
This section is empty.
Functions ¶
func CloseCards ¶
func CloseCards(cards []*Card)
Types ¶
type AccessType ¶
type AccessType int
const ( MmapInterleaved AccessType = iota MmapNonInterleaved MmapComplex RWInterleaved RWNonInterleaved AccessTypeLast = RWNonInterleaved AccessTypeFirst = MmapInterleaved )
func (AccessType) String ¶
func (a AccessType) String() string
type Buffer ¶
type Buffer struct {
Format BufferFormat
Data []byte
}
type BufferFormat ¶
type BufferFormat struct {
SampleFormat FormatType
Rate int
Channels int
}
func (BufferFormat) String ¶
func (bp BufferFormat) String() string
type Device ¶
type Device struct {
Type DeviceType
Number int
Play, Record bool
Path string
Title string
// contains filtered or unexported fields
}
func (*Device) BufferFormat ¶
func (device *Device) BufferFormat() BufferFormat
BufferFormat() is not valid until after Prepare() is called
func (*Device) BytesPerFrame ¶
func (*Device) NegotiateBufferSize ¶
func (*Device) NegotiateChannels ¶
func (*Device) NegotiateFormat ¶
func (device *Device) NegotiateFormat(formats ...FormatType) (FormatType, error)
func (*Device) NegotiatePeriodSize ¶
func (*Device) NewBufferSeconds ¶
This function is deprecated and will be removed at some point. Please use NewBufferDuration
type DeviceType ¶
type DeviceType int
const ( UnknownDeviceType DeviceType = iota PCM )
func (DeviceType) String ¶
func (t DeviceType) String() string
type FormatType ¶
type FormatType int
const ( S8 FormatType = iota U8 S16_LE S16_BE U16_LE U16_BE S24_LE S24_BE U24_LE U24_BE S32_LE S32_BE U32_LE U32_BE FLOAT_LE FLOAT_BE FLOAT64_LE FLOAT64_BE // There are so many more... FormatTypeLast = FLOAT64_BE FormatTypeFirst = S8 )
const (
Unknown FormatType = -1
)
func (FormatType) String ¶
func (f FormatType) String() string
type SubformatType ¶
type SubformatType int
func (SubformatType) String ¶
func (f SubformatType) String() string
Source Files
Directories