Struct arithmetic_coding::Encoder

pub struct Encoder<'a, M, W> where
    M: Model,
    W: BitWrite,  { /* private fields */ }

An arithmetic encoder

An arithmetic decoder converts a stream of symbols into a stream of bits, using a predictive Model.

Implementations

impl<'a, M, W> Encoder<'a, M, W> where
    M: Model,
    W: BitWrite, 

pub fn new(model: M, bitwriter: &'a mut W) -> Self

Construct a new Encoder.

The ‘precision’ of the encoder is maximised, based on the number of bits needed to represent the Model::denominator. ‘precision’ bits is equal to BitStore::BITS - Model::denominator bits. If you need to set the precision manually, use Encoder::with_precision.

Panics

The calculation of the number of bits used for ‘precision’ is subject to the following constraints:

• The total available bits is BitStore::BITS
• The precision must use at least 2 more bits than that needed to represent Model::denominator

If these constraints cannot be satisfied this method will panic in debug builds

pub fn with_precision(model: M, bitwriter: &'a mut W, precision: u32) -> Self

Construct a new Encoder with a custom precision.

Panics

The calculation of the number of bits used for ‘precision’ is subject to the following constraints:

• The total available bits is BitStore::BITS
• The precision must use at least 2 more bits than that needed to represent Model::denominator

If these constraints cannot be satisfied this method will panic in debug builds

pub fn encode_all(
    &mut self,
    symbols: impl IntoIterator<Item = M::Symbol>
) -> Result<(), Error<M::ValueError>>

Encode a stream of symbols into the provided output.

This method will encode all the symbols in the iterator, followed by EOF (None), and then call Encoder::flush.

Errors

This method can fail if the underlying BitWrite cannot be written to.

pub fn encode(
    &mut self,
    symbol: Option<&M::Symbol>
) -> Result<(), Error<M::ValueError>>

Encode a symbol into the provided output.

When you finish encoding symbols, you must manually encode an EOF symbol by calling Encoder::encode with None.

The internal buffer must be manually flushed using Encoder::flush.

Errors

This method can fail if the underlying BitWrite cannot be written to.

pub fn flush(&mut self) -> Result<()>

Flush any pending bits from the buffer

This method must be called when you finish writing symbols to a stream of bits. This is called automatically when you use Encoder::encode_all.

Errors

This method can fail if the underlying BitWrite cannot be written to.

pub fn chain<X>(self, model: X) -> Encoder<'a, X, W> where
    X: Model<B = M::B>, 

Reuse the internal state of the Encoder with a new model.

Allows for chaining multiple sequences of symbols into a single stream of bits

Trait Implementations

impl<'a, M: Debug, W: Debug> Debug for Encoder<'a, M, W> where
    M: Model,
    W: BitWrite,
    M::B: Debug,
    M::B: Debug, 

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

Formats the value using the given formatter.