vortex_sampling_compressor/compressors/
varbin.rs

1use vortex_array::aliases::hash_set::HashSet;
2use vortex_array::array::{VarBinArray, VarBinEncoding};
3use vortex_array::{Array, Encoding, EncodingId, IntoArray};
4use vortex_error::VortexResult;
5
6use crate::compressors::{CompressedArray, CompressionTree, EncodingCompressor};
7use crate::downscale::downscale_integer_array;
8use crate::{constants, SamplingCompressor};
9
10#[derive(Debug)]
11pub struct VarBinCompressor;
12
13impl EncodingCompressor for VarBinCompressor {
14    fn id(&self) -> &str {
15        VarBinEncoding::ID.as_ref()
16    }
17
18    fn cost(&self) -> u8 {
19        constants::VARBIN_COST
20    }
21
22    fn can_compress(&self, array: &Array) -> Option<&dyn EncodingCompressor> {
23        array.is_encoding(VarBinEncoding::ID).then_some(self)
24    }
25
26    fn compress<'a>(
27        &'a self,
28        array: &Array,
29        like: Option<CompressionTree<'a>>,
30        ctx: SamplingCompressor<'a>,
31    ) -> VortexResult<CompressedArray<'a>> {
32        let varbin_array = VarBinArray::try_from(array.clone())?;
33        let offsets = ctx.auxiliary("offsets").compress(
34            &downscale_integer_array(varbin_array.offsets())?,
35            like.as_ref().and_then(|l| l.child(0)),
36        )?;
37        Ok(CompressedArray::compressed(
38            VarBinArray::try_new(
39                offsets.array,
40                varbin_array.bytes(), // we don't compress the raw bytes
41                array.dtype().clone(),
42                varbin_array.validity(),
43            )?
44            .into_array(),
45            Some(CompressionTree::new(self, vec![offsets.path, None, None])),
46            array,
47        ))
48    }
49
50    fn used_encodings(&self) -> HashSet<EncodingId> {
51        HashSet::from([VarBinEncoding::ID])
52    }
53}
vortex_sampling_compressor/compressors/varbin.rs

vortex_sampling_compressor/compressors/
varbin.rs
