aboutsummaryrefslogtreecommitdiff
path: root/vendor/tiff/src/encoder/compression/lzw.rs
diff options
context:
space:
mode:
authorValentin Popov <valentin@popov.link>2024-01-08 00:21:28 +0300
committerValentin Popov <valentin@popov.link>2024-01-08 00:21:28 +0300
commit1b6a04ca5504955c571d1c97504fb45ea0befee4 (patch)
tree7579f518b23313e8a9748a88ab6173d5e030b227 /vendor/tiff/src/encoder/compression/lzw.rs
parent5ecd8cf2cba827454317368b68571df0d13d7842 (diff)
downloadfparkan-1b6a04ca5504955c571d1c97504fb45ea0befee4.tar.xz
fparkan-1b6a04ca5504955c571d1c97504fb45ea0befee4.zip
Initial vendor packages
Signed-off-by: Valentin Popov <valentin@popov.link>
Diffstat (limited to 'vendor/tiff/src/encoder/compression/lzw.rs')
-rw-r--r--vendor/tiff/src/encoder/compression/lzw.rs47
1 files changed, 47 insertions, 0 deletions
diff --git a/vendor/tiff/src/encoder/compression/lzw.rs b/vendor/tiff/src/encoder/compression/lzw.rs
new file mode 100644
index 0000000..0e0f2aa
--- /dev/null
+++ b/vendor/tiff/src/encoder/compression/lzw.rs
@@ -0,0 +1,47 @@
+use crate::{encoder::compression::*, tags::CompressionMethod};
+use std::io::Write;
+use weezl::encode::Encoder as LZWEncoder;
+
+/// The LZW algorithm used to compress image data in TIFF files.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+pub struct Lzw;
+
+impl Compression for Lzw {
+ const COMPRESSION_METHOD: CompressionMethod = CompressionMethod::LZW;
+
+ fn get_algorithm(&self) -> Compressor {
+ Compressor::Lzw(*self)
+ }
+}
+
+impl CompressionAlgorithm for Lzw {
+ fn write_to<W: Write>(&mut self, writer: &mut W, bytes: &[u8]) -> Result<u64, io::Error> {
+ let mut encoder = LZWEncoder::with_tiff_size_switch(weezl::BitOrder::Msb, 8);
+ let result = encoder.into_stream(writer).encode_all(bytes);
+ let byte_count = result.bytes_written as u64;
+ result.status.map(|_| byte_count)
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+ use crate::encoder::compression::tests::TEST_DATA;
+ use std::io::Cursor;
+
+ #[test]
+ fn test_lzw() {
+ const EXPECTED_COMPRESSED_DATA: [u8; 63] = [
+ 0x80, 0x15, 0x0D, 0x06, 0x93, 0x98, 0x82, 0x08, 0x20, 0x30, 0x88, 0x0E, 0x67, 0x43,
+ 0x91, 0xA4, 0xDC, 0x67, 0x10, 0x19, 0x8D, 0xE7, 0x21, 0x01, 0x8C, 0xD0, 0x65, 0x31,
+ 0x9A, 0xE1, 0xD1, 0x03, 0xB1, 0x86, 0x1A, 0x6F, 0x3A, 0xC1, 0x4C, 0x66, 0xF3, 0x69,
+ 0xC0, 0xE4, 0x65, 0x39, 0x9C, 0xCD, 0x26, 0xF3, 0x74, 0x20, 0xD8, 0x67, 0x89, 0x9A,
+ 0x4E, 0x86, 0x83, 0x69, 0xCC, 0x5D, 0x01,
+ ];
+
+ let mut compressed_data = Vec::<u8>::new();
+ let mut writer = Cursor::new(&mut compressed_data);
+ Lzw::default().write_to(&mut writer, TEST_DATA).unwrap();
+ assert_eq!(EXPECTED_COMPRESSED_DATA, compressed_data.as_slice());
+ }
+}