chunk_diff/encoder/
mod.rs

1mod config;
2
3pub use config::Config;
4
5use crate::{
6    frame::{Changed, Frame},
7    hasher::Hasher,
8    util::{chunk::Chunk, point::Point},
9};
10use rayon::prelude::{IndexedParallelIterator, IntoParallelRefIterator, ParallelIterator};
11
12pub struct Encoder<T>
13where
14    T: Hasher,
15{
16    hasher: T,
17    config: Config,
18    chunks: Vec<Chunk>,
19    hashes: Vec<(Chunk, Vec<u64>)>,
20}
21
22impl<T> Encoder<T>
23where
24    T: Hasher + Sync,
25{
26    pub fn new(config: Config) -> Self
27    where
28        T: Default,
29    {
30        Self::new_with_hasher(T::default(), config)
31    }
32
33    pub fn new_with_hasher(hasher: T, config: Config) -> Self {
34        let full = config.full();
35        let rect = config.rect();
36        let chunks = full.divide(rect);
37        let size = chunks.len();
38
39        Self {
40            hasher,
41            config,
42            chunks,
43            hashes: Vec::with_capacity(size),
44        }
45    }
46
47    pub fn encode(&mut self, data: &[u8]) -> Vec<Frame> {
48        let full = self.config.full();
49
50        if data.len() != full.area() {
51            panic!("Data length does not match full rect area");
52        }
53
54        let hashes = self
55            .chunks
56            .par_iter()
57            .map(|chunk| (*chunk, self.hasher.hash_rect(data, chunk, full)))
58            .collect::<Vec<_>>();
59        let frames = if self.hashes.len() != hashes.len() {
60            let full_chunk = Chunk::new(Point::new(0, 0), *full);
61            vec![Frame::Changed(Changed::new(
62                full_chunk,
63                full_chunk.extract(data, full),
64            ))]
65        } else {
66            hashes
67                .par_iter()
68                .zip(self.hashes.par_iter())
69                .filter(|((_, new_hash), (_, old_hashes))| new_hash != old_hashes)
70                .map(|((chunk, _), (_, _))| {
71                    Frame::Changed(Changed::new(*chunk, chunk.extract(data, full)))
72                })
73                .collect::<Vec<_>>()
74        };
75
76        self.hashes = hashes;
77
78        frames
79    }
80}
chunk_diff/encoder/mod.rs

chunk_diff/encoder/
mod.rs
