Struct ChannelLayoutDescription 

pub struct ChannelLayoutDescription { /* private fields */ }

Available on crate features alloc or std only.

Audio channel layout, described in full — order + channel count + identification.

The bundle FFmpeg’s AVChannelLayout carries through to consumers, rendered as plain Rust data:

• order — Native / Custom / Ambisonic / Unspecified.
• channels — total count.
• known_kind — the layout’s name, as a ChannelLayout. ChannelLayout::default (the Other("") absent sentinel) when no well-known shape matches.
• native_mask — Some(bitmask) for ChannelOrder::Native / ChannelOrder::Ambisonic, None otherwise.
• custom_channels — populated for ChannelOrder::Custom layouts; one ChannelSpec per channel.
• text — the backend’s own free-form rendering, e.g. FFmpeg’s av_channel_layout_describe output ("5.1(side)", "3 channels (FL+FR+LFE)").

With the serde feature the wire form is a map of those six names, each field in its own shape: order as its u32 code, known_kind as its canonical slug, native_mask as a nullable integer, custom_channels as an array of ChannelSpec maps.

No invariant across the fields. An incoherent combination — a Custom order with an empty channel list, a Native order with no mask — is exactly as constructible through the public setters as a coherent one, so the derive rejects nothing the builders would have accepted, and the fuzz generators deliberately reach those combinations. A consumer that needs coherence checks it.

Implementations

impl ChannelLayoutDescription

pub const fn new(channels: u32) -> Self

Constructs a minimal description with the given channel count. Every other field starts at its own absent value (Unspecified order, no name, no mask, no channel list, no rendering); fill them in with the with_* builders.

pub const fn order(&self) -> ChannelOrder

Channel ordering (Native / Custom / Ambisonic / Unspecified).

pub const fn channels(&self) -> u32

Total channel count.

pub const fn known_kind(&self) -> &ChannelLayout

The layout’s name, or ChannelLayout::default — the Other("") absent sentinel — when no well-known shape matches.

Borrowed rather than copied: ChannelLayout carries a SmolStr in its escape arm and so is not Copy.

pub const fn native_mask(&self) -> Option<u64>

Native-order bitmask of AV_CH_* channel positions, when applicable. None for Custom / Unspecified orders, or when the mask is zero.

pub const fn custom_channels(&self) -> &[ChannelSpec]

Per-channel descriptors for ChannelOrder::Custom layouts; empty otherwise.

pub fn text(&self) -> &str

The backend’s own free-form rendering of this layout — FFmpeg’s av_channel_layout_describe output ("5.1(side)", "3 channels (FL+FR+LFE)"), empty when there is none.

Not a slug: this is what the backend printed, verbatim, and it is the seat that keeps a layout no vocabulary can name from being lost entirely. known_kind is the parsed name; this is the rendering.

pub fn is_empty(&self) -> bool

true when every field is at its absent value — zero channels, Unspecified order, no name, no mask, no custom channels, no rendering. Useful as an “uninitialized” sentinel.

pub const fn with_order(self, v: ChannelOrder) -> Self

Sets the order — consuming builder.

pub const fn with_channels(self, v: u32) -> Self

Sets the channel count — consuming builder.

pub fn with_known_kind(self, v: ChannelLayout) -> Self

Sets the layout’s name — consuming builder.

pub const fn with_native_mask(self, v: Option<u64>) -> Self

Sets the native-order bitmask — consuming builder.

pub fn with_custom_channels(self, v: Vec<ChannelSpec>) -> Self

Sets the custom-order channel list — consuming builder.

pub fn with_text(self, v: impl Into<SmolStr>) -> Self

Sets the backend’s rendering — consuming builder.

pub const fn set_order(&mut self, v: ChannelOrder) -> &mut Self

Sets the order in place.

pub const fn set_channels(&mut self, v: u32) -> &mut Self

Sets the channel count in place.

pub fn set_known_kind(&mut self, v: ChannelLayout) -> &mut Self

Sets the layout’s name in place.

pub const fn set_native_mask(&mut self, v: Option<u64>) -> &mut Self

Sets the native-order bitmask in place.

pub fn set_custom_channels(&mut self, v: Vec<ChannelSpec>) -> &mut Self

Sets the custom-order channel list in place.

pub fn set_text(&mut self, v: impl Into<SmolStr>) -> &mut Self

Sets the backend’s rendering in place.

Trait Implementations

impl Arbitrary for ChannelLayoutDescription

fn arbitrary(__quickcheck_g: &mut Gen) -> Self

Return an arbitrary value.

fn shrink(&self) -> Box<dyn Iterator<Item = Self>>

Return an iterator of values that are smaller than itself.

impl<'a> Arbitrary<'a> for ChannelLayoutDescription

Available on crate feature arbitrary only.

fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self>

Generate an arbitrary value of Self from the given unstructured data.

fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self, Error>

Generate an arbitrary value of Self from the entirety of the given unstructured data.

fn size_hint(depth: usize) -> (usize, Option<usize>)

Get a size hint for how many bytes out of an Unstructured this type needs to construct itself.

fn try_size_hint( depth: usize, ) -> Result<(usize, Option<usize>), MaxRecursionReached>

Get a size hint for how many bytes out of an Unstructured this type needs to construct itself.

impl Clone for ChannelLayoutDescription

fn clone(&self) -> ChannelLayoutDescription

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ChannelLayoutDescription

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

Formats the value using the given formatter.

impl Default for ChannelLayoutDescription

fn default() -> Self

Delegates to ChannelLayoutDescription::new with zero channels — the “uninitialized” sentinel Self::is_empty recognises.

impl DefaultInstance for ChannelLayoutDescription

Available on crate feature buffa only.

fn default_instance() -> &'static Self

Return a reference to the single default instance of this type.

impl<'de> Deserialize<'de> for ChannelLayoutDescription

where ChannelLayoutDescription: Default,

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for ChannelLayoutDescription

impl Hash for ChannelLayoutDescription

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Message for ChannelLayoutDescription

Available on crate feature buffa only.

fn compute_size(&self, cache: &mut SizeCache) -> u32

Compute the encoded byte size of this message, recording nested sub-message sizes in cache for write_to to consume.

fn write_to(&self, cache: &mut SizeCache, buf: &mut impl EncodeSink)

Write this message’s encoded bytes to a buffer, consuming nested-message sizes from cache (populated by a prior compute_size call on the same cache).

fn merge_field( &mut self, tag: Tag, buf: &mut impl Buf, ctx: DecodeContext<'_>, ) -> Result<(), DecodeError>

Processes a single already-decoded tag and its associated field data from buf.

fn clear(&mut self)

Clear all fields to their default values.

fn encode(&self, buf: &mut impl EncodeSink)

Compute size, then write. This is the primary encoding API.

fn try_encode(&self, buf: &mut impl EncodeSink) -> Result<(), EncodeError>

Encode, returning an error instead of panicking if the encoded size exceeds the 2 GiB protobuf limit (MAX_MESSAGE_BYTES).

fn encode_with_cache(&self, cache: &mut SizeCache, buf: &mut impl EncodeSink)

Encode using a caller-supplied SizeCache, for reuse across many encodes in a hot loop. Clears the cache first.

fn try_encode_with_cache( &self, cache: &mut SizeCache, buf: &mut impl EncodeSink, ) -> Result<(), EncodeError>

Encode with a caller-supplied SizeCache, returning an error instead of panicking if the encoded size exceeds the 2 GiB protobuf limit (MAX_MESSAGE_BYTES). Clears the cache first.

fn try_encode_bounded( &self, max_bytes: u32, buf: &mut impl EncodeSink, ) -> Result<u32, EncodeError>

Encode this message into buf only if its encoded size fits within max_bytes, using a single size pass that is then reused for the write.

fn try_encode_bounded_with_cache( &self, max_bytes: u32, cache: &mut SizeCache, buf: &mut impl EncodeSink, ) -> Result<u32, EncodeError>

Like try_encode_bounded but reuses an existing SizeCache, clearing it first.

fn encoded_len(&self) -> u32

Compute the encoded byte size of this message.

fn try_encoded_len(&self) -> Result<u32, EncodeError>

Compute the encoded byte size, returning an error instead of panicking if it exceeds the 2 GiB protobuf limit (MAX_MESSAGE_BYTES).

fn encode_length_delimited(&self, buf: &mut impl EncodeSink)

Encode this message as a length-delimited byte sequence.

fn try_encode_length_delimited( &self, buf: &mut impl EncodeSink, ) -> Result<(), EncodeError>

Encode as a length-delimited byte sequence, returning an error instead of panicking if the encoded size exceeds the 2 GiB protobuf limit (MAX_MESSAGE_BYTES).

fn encode_to_vec(&self) -> Vec<u8>

Encode this message to a new Vec<u8>.

fn try_encode_to_vec(&self) -> Result<Vec<u8>, EncodeError>

Encode to a new Vec<u8>, returning an error instead of panicking if the encoded size exceeds the 2 GiB protobuf limit (MAX_MESSAGE_BYTES).

fn encode_to_bytes(&self) -> Bytes

Encode this message to a new bytes::Bytes.

fn try_encode_to_bytes(&self) -> Result<Bytes, EncodeError>

Encode to a new bytes::Bytes, returning an error instead of panicking if the encoded size exceeds the 2 GiB protobuf limit (MAX_MESSAGE_BYTES).

fn decode(buf: &mut impl Buf) -> Result<Self, DecodeError>

where Self: Sized,

Decode a message from a buffer.

fn decode_from_slice(data: &[u8]) -> Result<Self, DecodeError>

where Self: Sized,

Decode a message from a byte slice.

fn decode_length_delimited(buf: &mut impl Buf) -> Result<Self, DecodeError>

where Self: Sized,

Decode a length-delimited message from a buffer.

fn merge_to_limit( &mut self, buf: &mut impl Buf, ctx: DecodeContext<'_>, limit: usize, ) -> Result<(), DecodeError>

Merge fields from a buffer until buf.remaining() reaches limit.

fn merge_group( &mut self, buf: &mut impl Buf, ctx: DecodeContext<'_>, field_number: u32, ) -> Result<(), DecodeError>

Merges a group-encoded message from buf, reading fields until an EndGroup tag with the given field_number is encountered.

fn merge( &mut self, buf: &mut impl Buf, ctx: DecodeContext<'_>, ) -> Result<(), DecodeError>

Merge fields from a buffer into this message.

fn merge_from_slice(&mut self, data: &[u8]) -> Result<(), DecodeError>

Merge fields from a byte slice into this message.

fn merge_length_delimited( &mut self, buf: &mut impl Buf, ctx: DecodeContext<'_>, ) -> Result<(), DecodeError>

Merge fields from a length-delimited sub-message payload into this message.

impl PartialEq for ChannelLayoutDescription

fn eq(&self, other: &ChannelLayoutDescription) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for ChannelLayoutDescription

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for ChannelLayoutDescription