feat: Add ZSTD Decoder

Cargo.toml

@@ -21,6 +21,7 @@ reqwest = { version = "0.12", default-features = false, optional = true }
 thiserror = "1"
 tokio = { version = "1.43.0", default-features = false, features = ["sync"] }
 weezl = "0.1.0"
+zstd = "0.13"
 
 [dev-dependencies]
 object_store = { version = "0.12", features = ["http"] }

src/decoder.rs

@@ -38,12 +38,13 @@ impl AsMut<HashMap<CompressionMethod, Box<dyn Decoder>>> for DecoderRegistry {
 
 impl Default for DecoderRegistry {
     fn default() -> Self {
-        let mut registry = HashMap::with_capacity(5);
+        let mut registry = HashMap::with_capacity(6);
         registry.insert(CompressionMethod::None, Box::new(UncompressedDecoder) as _);
         registry.insert(CompressionMethod::Deflate, Box::new(DeflateDecoder) as _);
         registry.insert(CompressionMethod::OldDeflate, Box::new(DeflateDecoder) as _);
         registry.insert(CompressionMethod::LZW, Box::new(LZWDecoder) as _);
         registry.insert(CompressionMethod::ModernJPEG, Box::new(JPEGDecoder) as _);
+        registry.insert(CompressionMethod::ZSTD, Box::new(ZstdDecoder) as _);
         Self(registry)
     }
 }
@@ -125,6 +126,24 @@ impl Decoder for UncompressedDecoder {
     }
 }
 
+/// A decoder for the Zstd compression method.
+#[derive(Debug, Clone)]
+pub struct ZstdDecoder;
+
+impl Decoder for ZstdDecoder {
+    fn decode_tile(
+        &self,
+        buffer: Bytes,
+        _photometric_interpretation: PhotometricInterpretation,
+        _jpeg_tables: Option<&[u8]>,
+    ) -> AsyncTiffResult<Bytes> {
+        let mut decoder = zstd::Decoder::new(Cursor::new(buffer))?;
+        let mut buf = Vec::new();
+        decoder.read_to_end(&mut buf)?;
+        Ok(buf.into())
+    }
+}
+
 // https://github.com/image-rs/image-tiff/blob/3bfb43e83e31b0da476832067ada68a82b378b7b/src/decoder/image.rs#L389-L450
 fn decode_modern_jpeg(
     buf: Bytes,

tests/image_tiff/decode_images.rs

@@ -224,6 +224,17 @@ async fn test_int16_rgb() {
     assert!(ifd.bits_per_sample().iter().all(|x| *x == 16));
 }
 
+#[tokio::test]
+async fn test_zstd_compression() {
+    let tiff = open_tiff("int16_zstd.tif").await;
+    let ifd = &tiff.ifds()[0];
+    assert!(matches!(
+        ifd.photometric_interpretation(),
+        PhotometricInterpretation::BlackIsZero
+    ));
+    assert!(ifd.bits_per_sample().iter().all(|x| *x == 16));
+}
+
 #[tokio::test]
 async fn test_string_tags() {
     // these files have null-terminated strings for their Software tag. One has extra bytes after