media

type AudioParameters interface {
	// Return the channel layout
	ChannelLayout() string

	// Return the sample format
	SampleFormat() string

	// Return the sample rate (Hz)
	Samplerate() int
}

type Decoder interface {
	// Demultiplex media into packets. Pass a packet to a decoder function.
	// Stop when the context is cancelled or the end of the media stream is
	// reached.
	Demux(context.Context, DecoderFunc) error

	// Decode media into frames, and resample or resize the frame.
	// Stop when the context is cancelled or the end of the media stream is
	// reached.
	Decode(context.Context, FrameFunc) error
}

type DecoderFunc func(Packet) error

type DecoderMapFunc func(Stream) (Parameters, error)

type Device interface {
	// Device name, format depends on the device
	Name() string

	// Description of the device
	Description() string

	// Flags indicating the type INPUT or OUTPUT, AUDIO or VIDEO
	Type() MediaType

	// Whether this is the default device
	Default() bool
}

type Format interface {
	// Name(s) of the format
	Name() []string

	// Description of the format
	Description() string

	// Extensions associated with the format, if a stream. Each extension
	// should have a preceeding period (ie, ".mp4")
	Extensions() []string

	// MimeTypes associated with the format
	MimeTypes() []string

	// Flags indicating the type. INPUT for a demuxer or source, OUTPUT for a muxer or
	// sink, DEVICE for a device, FILE for a file. Plus AUDIO, VIDEO, DATA, SUBTITLE.
	Type() MediaType
}

type Frame interface{}

type FrameFunc func(Frame) error

type Manager interface {
	// Open a media file or device for reading, from a path or url.
	// If a format is specified, then the format will be used to open
	// the file. Close the media object when done.
	Open(string, Format, ...string) (Media, error)

	// Open a media stream for reading.  If a format is
	// specified, then the format will be used to open the file. Close the
	// media object when done. It is the responsibility of the caller to
	// also close the reader when done.
	Read(io.Reader, Format, ...string) (Media, error)

	// Create a media file or device for writing, from a path. If a format is
	// specified, then the format will be used to create the file. Close
	// the media object when done.
	// TODO
	Create(string, Format) (Media, error)

	// Create a media stream for writing. If a format is
	// specified, then the format will be used to create the file.
	// Close the media object when done. It is the responsibility of the caller to
	// also close the writer when done.
	// TODO
	Write(io.Writer, Format) (Media, error)

	// Return supported input formats which match any filter, which can be
	// a name, extension (with preceeding period) or mimetype. The MediaType
	// can be NONE (for any) or combinations of DEVICE and STREAM.
	InputFormats(MediaType, ...string) []Format

	// Return supported output formats which match any filter, which can be
	// a name, extension (with preceeding period) or mimetype. The MediaType
	// can be NONE (for any) or combinations of DEVICE and STREAM.
	OutputFormats(MediaType, ...string) []Format

	// Return supported input devices for a given format name
	// Not all devices may be supported on all platforms or listed
	// if the device does not support enumeration.
	InputDevices(string) []Device

	// Return supported output devices for a given format name
	// Not all devices may be supported on all platforms or listed
	// if the device does not support enumeration.
	OutputDevices(string) []Device

	// Return all supported channel layouts
	ChannelLayouts() []Metadata

	// Return all supported sample formats
	SampleFormats() []Metadata

	// Return all supported  pixel formats
	PixelFormats() []Metadata

	// Return audio parameters for encoding
	// ChannelLayout, SampleFormat, Samplerate
	AudioParameters(string, string, int) (AudioParameters, error)

	// Return video parameters for encoding
	// Width, Height, PixelFormat, Framerate
	VideoParameters(int, int, string, float64) (VideoParameters, error)

	// Return version information for the media manager as a set of
	// metadata
	Version() []Metadata
}

type Media interface {
	io.Closer

	// Return a decoding context for the media stream, and
	// map the streams to decoders. If no function is provided
	// (ie, the argument is nil) then all streams are demultiplexed.
	Decoder(DecoderMapFunc) (Decoder, error)

	// Return INPUT for a demuxer or source, OUTPUT for a muxer or
	// sink, DEVICE for a device, FILE for a file or stream.
	Type() MediaType

	// Return the metadata for the media.
	Metadata() []Metadata
}

type MediaType uint32

type Metadata interface{}

type Packet interface{}

type Parameters interface {
	AudioParameters
	VideoParameters

	// Return the media type (AUDIO, VIDEO, SUBTITLE, DATA)
	Type() MediaType
}

type Stream interface {
	// Return AUDIO, VIDEO, SUBTITLE or DATA
	Type() MediaType

	// Return the stream parameters
	Parameters() Parameters
}

type VideoParameters interface {
	// Return the width of the video frame
	Width() int

	// Return the height of the video frame
	Height() int

	// Return the pixel format
	PixelFormat() string

	// Return the frame rate (fps)
	Framerate() float64
}