exr/compression/
zip.rs

1
2// see https://github.com/openexr/openexr/blob/master/OpenEXR/IlmImf/ImfCompressor.cpp
3
4
5use super::*;
6use super::optimize_bytes::*;
7use crate::error::Result;
8
9// scanline decompression routine, see https://github.com/openexr/openexr/blob/master/OpenEXR/IlmImf/ImfScanLineInputFile.cpp
10// 1. Uncompress the data, if necessary (If the line is uncompressed, it's in XDR format, regardless of the compressor's output format.)
11// 3. Convert one scan line's worth of pixel data back from the machine-independent representation
12// 4. Fill the frame buffer with pixel data, respective to sampling and whatnot
13
14
15pub fn decompress_bytes(
16    channels: &ChannelList,
17    data: ByteVec,
18    rectangle: IntegerBounds,
19    expected_byte_size: usize,
20    _pedantic: bool,
21) -> Result<ByteVec> {
22    let options = zune_inflate::DeflateOptions::default().set_limit(expected_byte_size).set_size_hint(expected_byte_size);
23    let mut decoder = zune_inflate::DeflateDecoder::new_with_options(&data, options);
24    let mut decompressed = decoder.decode_zlib()
25        .map_err(|_| Error::invalid("zlib-compressed data malformed"))?;
26
27    differences_to_samples(&mut decompressed);
28    interleave_byte_blocks(&mut decompressed);
29
30    Ok(super::convert_little_endian_to_current(decompressed, channels, rectangle))// TODO no alloc
31}
32
33pub fn compress_bytes(channels: &ChannelList, uncompressed: ByteVec, rectangle: IntegerBounds) -> Result<ByteVec> {
34    // see https://github.com/AcademySoftwareFoundation/openexr/blob/3bd93f85bcb74c77255f28cdbb913fdbfbb39dfe/OpenEXR/IlmImf/ImfTiledOutputFile.cpp#L750-L842
35    let mut packed = convert_current_to_little_endian(uncompressed, channels, rectangle);
36
37    separate_bytes_fragments(&mut packed);
38    samples_to_differences(&mut packed);
39
40    Ok(miniz_oxide::deflate::compress_to_vec_zlib(packed.as_slice(), 4))
41}
exr/compression/zip.rs

exr/compression/
zip.rs
