Struct ProtectionCoverage 

pub struct ProtectionCoverage { /* private fields */ }

The assignment of media packets to repair packets.

Repair packets are interleaved: with two of them, the first covers media packets 0, 2, 4, … and the second covers 1, 3, 5, …. Interleaving is what makes the scheme tolerate a burst — consecutive losses land in different repair packets, and each can be recovered independently, whereas contiguous blocks would put a burst entirely inside one and recover none of it.

Implementations

impl ProtectionCoverage

pub fn new(num_media_packets: u32, num_fec_packets: u32) -> Option<Self>

Assign num_media_packets media packets across num_fec_packets repair packets.

Returns None when the media count is zero or beyond what the masks can describe.

pub fn update(&mut self, num_media_packets: u32, num_fec_packets: u32)

Recompute the assignment for a new block shape.

A no-op when the shape has not changed, which is the common case: a sender protecting a steady stream keeps the same counts block after block.

pub fn num_fec_packets(&self) -> u32

How many repair packets this covers.

pub fn num_media_packets(&self) -> u32

How many media packets this covers.

pub fn mask(&self, fec_index: u32) -> Option<&BitArray>

The packet mask of one repair packet.

pub fn covered_by(&self, fec_index: u32) -> Vec<u32>

The media packet indices that fec_index protects, in order.

Upstream returns a stateful iterator with Reset/First/HasNext, because its encoder walks the same coverage three times. A plain Vec of indices says the same thing without the cursor, and the caller can walk it as often as it likes.

Trait Implementations

impl Clone for ProtectionCoverage

fn clone(&self) -> ProtectionCoverage

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ProtectionCoverage

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

Formats the value using the given formatter.