Enum EncodingScheme 

pub enum EncodingScheme {
    BalancedTree,
    Fano,
    Shannon,
    Huffman,
}

Encoding schems (i.e. the compression algorithms) supported by this library.

Variants

BalancedTree

Create a new balanced tree encoding.

All letters in this encoding are fixed width bit strings. The smallest width necessary to generate the required number of letters for all input tokens is used.

Fano

Create a new Fano encoding.

Shannon

Create a new Shannon encoding.

The Shannon encoding scheme is defined thus:

Let the tokens, sorted in decreasing order of frequency be t1, t2, t3 ...

Let the probability of occurrence of the Tokens be f1, f2, f3 ...

Define the numbers l1, l2, l3 ... such that lk = ceil(log2(1/fk))

Let the (computed) cumulative proportions be c1, c2, c3 ...

Then, the code is e1, e2, e3 ... such that ek = first lk bits of the binary expansion of Fk.

Huffman

Create a new Huffman encoding.

Of the algorithms implemented in this library, this is closest to practical compression libraries used widely - e.g., deflate, jpeg and mp3 use a Huffman-like encoding in their backends.

Trait Implementations

impl Clone for EncodingScheme

fn clone(&self) -> EncodingScheme

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for EncodingScheme

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

Formats the value using the given formatter.

impl Hash for EncodingScheme

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 PartialEq for EncodingScheme

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for EncodingScheme

impl Eq for EncodingScheme

impl StructuralPartialEq for EncodingScheme