Struct BoolDecoder 

pub struct BoolDecoder<'a> { /* private fields */ }

VP8 boolean entropy decoder (RFC 6386 §7.3).

Reads the bools/literals/tree symbols written by a BoolEncoder, in the same order and with the same probabilities. Reading past the end of the partition yields zero bits (matching the reference decoders’ zero-padding) rather than panicking; BoolDecoder::is_past_end reports whether that has happened, so the codec layer can reject a truncated stream.

Implementations

impl<'a> BoolDecoder<'a>

pub fn new(input: &'a [u8]) -> Self

Creates a decoder over input, priming value with the first two bytes (zero-padded if input is shorter), per RFC 6386 §7.3 init_bool_decoder.

pub fn get_bool(&mut self, prob: Prob) -> bool

Decodes one bool encoded at probability prob / 256 (RFC 6386 §7.3 read_bool).

pub fn get_flag(&mut self) -> bool

Decodes a one-bit flag (a bool at probability 128) — the F / L(1) of §8.

pub fn get_literal(&mut self, num_bits: u32) -> u32

Decodes an unsigned num_bits-bit literal L(num_bits), high-order bit first (RFC 6386 §7.3 read_literal). num_bits must be 0..=32.

pub fn get_signed_literal(&mut self, num_bits: u32) -> i32

Decodes a signed num_bits-bit literal (RFC 6386 §7.3 read_signed_literal): a sign flag followed by num_bits - 1 magnitude bits.

pub fn get_tree_start( &mut self, tree: &Tree, probs: &[Prob], start: usize, ) -> usize

Decodes a tree-coded value from tree with interior-node probabilities probs, beginning the descent at interior node start (RFC 6386 §8.1 treed_read).

pub fn get_tree(&mut self, tree: &Tree, probs: &[Prob]) -> usize

Decodes a tree-coded value from the root (equivalent to get_tree_start with start = 0).

pub fn is_past_end(&self) -> bool

Whether a read has consumed input beyond the end of the partition (zero-padded). A correct, untruncated stream never reads past its meaningful end by more than the coder’s lookahead, so the codec layer can use this to detect a malformed or truncated partition.

Trait Implementations

impl<'a> Clone for BoolDecoder<'a>

fn clone(&self) -> BoolDecoder<'a>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a> Debug for BoolDecoder<'a>

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

Formats the value using the given formatter.