Struct AudioRef 

pub struct AudioRef<'a, S: FrameFree<RawFrame = NDIlib_audio_frame_v3_t>> { /* private fields */ }

A zero-copy borrowed audio frame, generic over its free strategy S.

This type wraps an RAII Guard that owns the NDI frame buffer lifetime, exposing a safe, zero-copy view of the audio data. The frame is automatically freed when dropped, via whichever NDIlib_*_free_audio* call the strategy S encodes.

The shared accessors and the Debug impl are written exactly once here; the two public spellings are aliases that layer their differing format/owned/empty policy on top:

• AudioFrameRef<'rx> — frames captured from a Receiver (always concrete: format() -> AudioFormat, to_owned() -> AudioFrame).
• FrameSyncAudioRef<'fs> — frames captured from a FrameSync, which additionally model a validated empty query/no-source state (is_empty, Option-returning format/to_owned).

Key characteristics:

• Zero allocations: References NDI SDK buffers directly
• Zero copies: No memcpy of audio samples
• RAII lifetime: Exactly one free per frame, enforced at compile time
• Receiver refs are Send + Sync; FrameSync refs stay on their capture thread

Implementations

impl<'a, S: FrameFree<RawFrame = NDIlib_audio_frame_v3_t>> AudioRef<'a, S>

pub fn sample_rate(&self) -> i32

Get the sample rate in Hz.

pub fn num_channels(&self) -> i32

Get the number of audio channels.

pub fn num_samples(&self) -> i32

Get the number of samples per channel.

pub fn timecode(&self) -> i64

Get the timecode in 100 ns units.

pub fn timestamp(&self) -> i64

Get the receive timestamp in 100 ns units since the Unix epoch.

pub fn channel_stride_in_bytes(&self) -> i32

Get the channel stride in bytes.

pub fn metadata(&self) -> Option<&str>

Get frame metadata as UTF-8 text, if present.

pub fn data(&self) -> Option<&[f32]>

Get a zero-copy slice when channels are tightly packed.

Returns None for multi-channel buffers with padding between channels. Use channel_data or channels for those buffers. An empty query/no-source frame returns Some(&[]).

pub fn channel_data(&self, channel: usize) -> Option<&[f32]>

Get the zero-copy samples for a single channel, excluding padding.

pub fn channels(&self) -> impl ExactSizeIterator<Item = &[f32]> + '_

Iterate over channel slices without reading inter-channel padding. Empty query/no-source frames yield no channels.

impl<'rx> AudioRef<'rx, AudioKind>

pub fn format(&self) -> AudioFormat

Get the audio format (FourCC code).

This is guaranteed to be a valid, supported format since it’s validated during construction.

pub fn to_owned(&self) -> Result<AudioFrame>

Convert this borrowed frame to an owned AudioFrame.

Copies channel samples into tightly packed planar storage and copies metadata, allowing the frame to outlive the SDK buffer. Padding is omitted.

impl<'fs> AudioRef<'fs, FrameSyncAudioFree>

pub fn is_empty(&self) -> bool

Returns true for a valid query/no-source state with no sample buffer.

pub fn format(&self) -> Option<AudioFormat>

Get the audio format (FourCC code), or None for an empty query/no-source state.

pub fn to_owned(&self) -> Result<Option<AudioFrame>>

Convert this borrowed frame to an owned AudioFrame.

Copies channel samples into tightly packed planar storage and copies metadata, allowing the frame to outlive the SDK buffer. Padding is omitted.

Returns Ok(None) for a valid query/no-source state with no sample buffer to own.

Trait Implementations

impl<'a, S: FrameFree<RawFrame = NDIlib_audio_frame_v3_t>> Debug for AudioRef<'a, S>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.