subsonic-tui/vendor/github.com/gopxl/beep/interface.go
Sagi Dayan 48661005be
initial commit
Signed-off-by: Sagi Dayan <sagidayan@gmail.com>
2024-09-01 16:30:56 +03:00

106 lines
3.4 KiB
Go

package beep
// Streamer is able to stream a finite or infinite sequence of audio samples.
type Streamer interface {
// Stream copies at most len(samples) next audio samples to the samples slice.
//
// The sample rate of the samples is unspecified in general, but should be specified for
// each concrete Streamer.
//
// The value at samples[i][0] is the value of the left channel of the i-th sample.
// Similarly, samples[i][1] is the value of the right channel of the i-th sample.
//
// Stream returns the number of streamed samples. If the Streamer is drained and no more
// samples will be produced, it returns 0 and false. Stream must not touch any samples
// outside samples[:n].
//
// There are 3 valid return patterns of the Stream method:
//
// 1. n == len(samples) && ok
//
// Stream streamed all the requested samples. Cases 1, 2 and 3 may occur in the following
// calls.
//
// 2. 0 < n && n < len(samples) && ok
//
// Stream streamed n samples and drained the Streamer. Only case 3 may occur in the
// following calls.
//
// 3. n == 0 && !ok
//
// The Streamer is drained and no more samples will come. If Err returns a non-nil error, only
// this case is valid. Only this case may occur in the following calls.
Stream(samples [][2]float64) (n int, ok bool)
// Err returns an error which occurred during streaming. If no error occurred, nil is
// returned.
//
// When an error occurs, Streamer must become drained and Stream must return 0, false
// forever.
//
// The reason why Stream doesn't return an error is that it dramatically simplifies
// programming with Streamer. It's not very important to catch the error right when it
// happens.
Err() error
}
// StreamSeeker is a finite duration Streamer which supports seeking to an arbitrary position.
type StreamSeeker interface {
Streamer
// Duration returns the total number of samples of the Streamer.
Len() int
// Position returns the current position of the Streamer. This value is between 0 and the
// total length.
Position() int
// Seek sets the position of the Streamer to the provided value.
//
// If an error occurs during seeking, the position remains unchanged. This error will not be
// returned through the Streamer's Err method.
Seek(p int) error
}
// StreamCloser is a Streamer streaming from a resource which needs to be released, such as a file
// or a network connection.
type StreamCloser interface {
Streamer
// Close closes the Streamer and releases it's resources. Streamer will no longer stream any
// samples.
Close() error
}
// StreamSeekCloser is a union of StreamSeeker and StreamCloser.
type StreamSeekCloser interface {
Streamer
Len() int
Position() int
Seek(p int) error
Close() error
}
// StreamerFunc is a Streamer created by simply wrapping a streaming function (usually a closure,
// which encloses a time tracking variable). This sometimes simplifies creating new streamers.
//
// Example:
//
// noise := StreamerFunc(func(samples [][2]float64) (n int, ok bool) {
// for i := range samples {
// samples[i][0] = rand.Float64()*2 - 1
// samples[i][1] = rand.Float64()*2 - 1
// }
// return len(samples), true
// })
type StreamerFunc func(samples [][2]float64) (n int, ok bool)
// Stream calls the wrapped streaming function.
func (sf StreamerFunc) Stream(samples [][2]float64) (n int, ok bool) {
return sf(samples)
}
// Err always returns nil.
func (sf StreamerFunc) Err() error {
return nil
}