huffman-compress

Crates.iohuffman-compress
lib.rshuffman-compress
version0.6.1
sourcesrc
created_at2018-01-29 00:23:21.08549
updated_at2021-04-25 21:13:29.608035
descriptionHuffman compression given a probability distribution over arbitrary symbols
homepage
repositoryhttps://github.com/niklasf/rust-huffman-compress
max_upload_size
id48719
size34,635
(kraktus)

documentation

README

huffman-compress

Huffman compression given a probability distribution over arbitrary symbols.

Build Status crates.io docs.rs No Maintenance Intended

Examples

use std::iter::FromIterator;
use std::collections::HashMap;
use bit_vec::BitVec;
use huffman_compress::{CodeBuilder, Book, Tree};

let mut weights = HashMap::new();
weights.insert("CG", 293);
weights.insert("AG", 34);
weights.insert("AT", 4);
weights.insert("CT", 4);
weights.insert("TG", 1);

// Construct a Huffman code based on the weights (e.g. counts or relative
// frequencies).
let (book, tree) = CodeBuilder::from_iter(weights).finish();

// More frequent symbols will be encoded with fewer bits.
assert!(book.get("CG").map_or(0, |cg| cg.len()) <
        book.get("AG").map_or(0, |ag| ag.len()));

// Encode some symbols using the book.
let mut buffer = BitVec::new();
let example = vec!["AT", "CG", "AT", "TG", "AG", "CT", "CT", "AG", "CG"];
for symbol in &example {
    book.encode(&mut buffer, symbol);
}

// Decode the symbols using the tree.
let decoded: Vec<&str> = tree.decoder(&buffer).collect();
assert_eq!(decoded, example);

Documentation

Read the documentation

Changelog

  • 0.6.1
    • Fix deprecation warning and remove #[deny(warnings)] (a future compatibility hazard in libraries).
  • 0.6.0
    • Update to bit-vec 0.6.
  • 0.5.0
    • Update to bit-vec 0.5.
  • 0.4.0
    • Renamed Tree::decoder() to Tree::unbounded_decoder() to avoid surprises. A new Tree::decoder() takes the maximum number of symbols to decode.
    • No longer reexporting Saturating from num-traits.
  • 0.3.2
    • Preallocate arena space for Huffman tree.
  • 0.3.1
    • Update num-traits to 0.2 (semver compatible).
  • 0.3.0
    • Introduce CodeBuilder.
    • Changes tie breaking order.
  • 0.2.0
    • Allow initialization from iterators without creating a HashMap. Thanks @mernen.
    • Require K: Ord instead of K: Hash + Eq for symbols and switch Book internals from HashMap to BTreeMap.
    • Specify stability guarantees.
  • 0.1.1
    • Expose more methods on Book.
  • 0.1.0
    • Initial release.

License

huffman-compress is dual licensed under the Apache 2.0 and MIT license, at your option.

Commit count: 93

cargo fmt