Update notes and metadata for 0.5.0

Fix #69

CHANGES.md

@@ -1,3 +1,12 @@
+# Version 0.5.0
+
+* Added support for 32-bit and 64-bit decoded values.
+* Added CMYK(16|32|64) color type support.
+* Check many internal integer conversions to increase stability. This should
+  only lead to images being reported as faulty that would previously silently
+  break platform limits. If there are any false positives, please report them.
+* Remove an erroneous check of decoded length in lzw compressed images.
+
 # Version 0.4.0
 
 * Several enumerations are now non_exhaustive for future extensions.

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "tiff"
-version = "0.4.0"
+version = "0.5.0"
 authors = [
     "ccgn",
     "bvssvni <bvssvni@gmail.com>",

src/decoder/ifd.rs

@@ -9,7 +9,8 @@ use super::stream::{ByteOrder, EndianReader, SmartReader};
 use tags::{Tag, Type};
 use {TiffError, TiffFormatError, TiffResult, TiffUnsupportedError};
 
-use self::Value::{Ascii, List, Rational, SRational, Signed, Unsigned};
+use self::Value::{Ascii, List, Rational, Unsigned, Signed, SRational};
+
 
 #[allow(unused_qualifications)]
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
@@ -71,7 +72,7 @@ impl Value {
                             new_vec.push(numerator);
                             new_vec.push(denominator);
                         }
-                        _ => new_vec.push(v.into_i32()?),
+                        _ => new_vec.push(v.into_i32()?)
                     }
                 }
                 Ok(new_vec)
@@ -181,10 +182,16 @@ impl Entry {
                 Ok(SRational(numerator, denominator))
             }
             (Type::RATIONAL, n) => self.decode_offset(n, bo, limits, decoder, |decoder| {
-                Ok(Rational(decoder.read_long()?, decoder.read_long()?))
+                Ok(Rational(
+                    decoder.read_long()?,
+                    decoder.read_long()?,
+                ))
             }),
             (Type::SRATIONAL, n) => self.decode_offset(n, bo, limits, decoder, |decoder| {
-                Ok(SRational(decoder.read_slong()?, decoder.read_slong()?))
+                Ok(SRational(
+                    decoder.read_slong()?,
+                    decoder.read_slong()?,
+                ))
             }),
             (Type::ASCII, n) => {
                 let n = usize::try_from(n)?;
@@ -202,14 +209,7 @@ impl Entry {
     }
 
     #[inline]
-    fn decode_offset<R, F>(
+    fn decode_offset<R, F>(&self, value_count: u32, bo: ByteOrder, limits: &super::Limits, decoder: &mut super::Decoder<R>, decode_fn: F) -> TiffResult<Value>
-        &self,
-        value_count: u32,
-        bo: ByteOrder,
-        limits: &super::Limits,
-        decoder: &mut super::Decoder<R>,
-        decode_fn: F,
-    ) -> TiffResult<Value>
         where
             R: Read + Seek,
             F: Fn(&mut super::Decoder<R>) -> TiffResult<Value>,
@@ -235,7 +235,7 @@ fn offset_to_bytes(n: usize, entry: &Entry) -> TiffResult<Value> {
         entry.offset[0..n]
             .iter()
             .map(|&e| Unsigned(u32::from(e)))
-            .collect(),
+            .collect()
     ))
 }
 
@@ -246,7 +246,7 @@ fn offset_to_sbytes(n: usize, entry: &Entry) -> TiffResult<Value> {
         entry.offset[0..n]
             .iter()
             .map(|&e| Signed(i32::from(e as i8)))
-            .collect(),
+            .collect()
     ))
 }
 

src/decoder/mod.rs

@@ -1,16 +1,14 @@
-use std::cmp;
-use std::collections::HashMap;
 use std::convert::TryFrom;
+use std::collections::HashMap;
 use std::io::{self, Read, Seek};
+use std::cmp;
 
 use {ColorType, TiffError, TiffFormatError, TiffResult, TiffUnsupportedError};
 
 use self::ifd::Directory;
 use tags::{CompressionMethod, PhotometricInterpretation, Predictor, Tag, Type};
 
-use self::stream::{
+use self::stream::{ByteOrder, EndianReader, LZWReader, DeflateReader, PackBitsReader, SmartReader};
-    ByteOrder, DeflateReader, EndianReader, LZWReader, PackBitsReader, SmartReader,
-};
 
 pub mod ifd;
 mod stream;
@@ -219,14 +217,8 @@ fn rev_hpredict(image: DecodingBuffer, size: (u32, u32), color_type: ColorType)
     let samples = match color_type {
         ColorType::Gray(8) | ColorType::Gray(16) | ColorType::Gray(32) | ColorType::Gray(64) => 1,
         ColorType::RGB(8) | ColorType::RGB(16) | ColorType::RGB(32) | ColorType::RGB(64) => 3,
-        ColorType::RGBA(8)
+        ColorType::RGBA(8) | ColorType::RGBA(16) | ColorType::RGBA(32) | ColorType::RGBA(64)
-        | ColorType::RGBA(16)
+        | ColorType::CMYK(8) | ColorType::CMYK(16) | ColorType::CMYK(32) | ColorType::CMYK(64) => 4,
-        | ColorType::RGBA(32)
-        | ColorType::RGBA(64)
-        | ColorType::CMYK(8)
-        | ColorType::CMYK(16)
-        | ColorType::CMYK(32)
-        | ColorType::CMYK(64) => 4,
         _ => {
             return Err(TiffError::UnsupportedError(
                 TiffUnsupportedError::HorizontalPredictor(color_type),
@@ -281,7 +273,8 @@ impl<R: Read + Seek> Decoder<R> {
 
     pub fn colortype(&mut self) -> TiffResult<ColorType> {
         match self.photometric_interpretation {
-            PhotometricInterpretation::RGB => match self.bits_per_sample[..] {
+            PhotometricInterpretation::RGB  => {
+                match self.bits_per_sample[..] {
                     [r, g, b] if [r, r] == [g, b] => Ok(ColorType::RGB(r)),
                     [r, g, b, a] if [r, r, r] == [g, b, a] => Ok(ColorType::RGBA(r)),
                     _ => Err(TiffError::UnsupportedError(
@@ -290,8 +283,10 @@ impl<R: Read + Seek> Decoder<R> {
                             self.bits_per_sample.clone(),
                         ),
                     )),
+                }
             },
-            PhotometricInterpretation::CMYK => match self.bits_per_sample[..] {
+            PhotometricInterpretation::CMYK => {
+                match self.bits_per_sample[..] {
                     [c, m, y, k] if [c, c, c] == [m, y, k] => Ok(ColorType::CMYK(c)),
                     _ => Err(TiffError::UnsupportedError(
                         TiffUnsupportedError::InterpretationWithBits(
@@ -299,6 +294,7 @@ impl<R: Read + Seek> Decoder<R> {
                             self.bits_per_sample.clone(),
                         ),
                     )),
+                }
             },
             PhotometricInterpretation::BlackIsZero | PhotometricInterpretation::WhiteIsZero
                 if self.bits_per_sample.len() == 1 =>
@@ -375,11 +371,9 @@ impl<R: Read + Seek> Decoder<R> {
             self.samples = val;
         }
         match self.samples {
-            1 | 3 | 4 => {
+            1 | 3 | 4 => if let Some(val) = self.find_tag_unsigned_vec(Tag::BitsPerSample)? {
-                if let Some(val) = self.find_tag_unsigned_vec(Tag::BitsPerSample)? {
                 self.bits_per_sample = val;
-                }
+            },
-            }
             _ => return Err(TiffUnsupportedError::UnsupportedSampleDepth(self.samples).into()),
         }
         Ok(())
@@ -522,30 +516,20 @@ impl<R: Read + Seek> Decoder<R> {
     /// Tries to retrieve a tag and convert it to the desired unsigned type.
     pub fn find_tag_unsigned<T: TryFrom<u32>>(&mut self, tag: Tag) -> TiffResult<Option<T>> {
         self.find_tag(tag)?
-            .map(|v| v.into_u32())
+            .map(|v| v.into_u32()).transpose()?
-            .transpose()?
+            .map(|value| T::try_from(value)
-            .map(|value| {
+                .map_err(|_| TiffFormatError::InvalidTagValueType(tag).into()))
-                T::try_from(value).map_err(|_| TiffFormatError::InvalidTagValueType(tag).into())
-            })
             .transpose()
     }
 
     /// Tries to retrieve a vector of all a tag's values and convert them to
     /// the desired unsigned type.
-    pub fn find_tag_unsigned_vec<T: TryFrom<u32>>(
+    pub fn find_tag_unsigned_vec<T: TryFrom<u32>>(&mut self, tag: Tag) -> TiffResult<Option<Vec<T>>> {
-        &mut self,
-        tag: Tag,
-    ) -> TiffResult<Option<Vec<T>>> {
         self.find_tag(tag)?
-            .map(|v| v.into_u32_vec())
+            .map(|v| v.into_u32_vec()).transpose()?
-            .transpose()?
+            .map(|v| v.into_iter()
-            .map(|v| {
+                .map(|u| T::try_from(u).map_err(|_| TiffFormatError::InvalidTagValueType(tag).into()))
-                v.into_iter()
+                .collect())
-                    .map(|u| {
-                        T::try_from(u).map_err(|_| TiffFormatError::InvalidTagValueType(tag).into())
-                    })
-                    .collect()
-            })
             .transpose()
     }
 
@@ -600,19 +584,21 @@ impl<R: Read + Seek> Decoder<R> {
                 let (bytes, reader) = LZWReader::new(
                     &mut self.reader,
                     usize::try_from(length)?,
-                    max_uncompressed_length,
+                    max_uncompressed_length * buffer.byte_len()
                 )?;
                 (bytes, Box::new(reader))
             }
             CompressionMethod::PackBits => {
                 let order = self.reader.byte_order;
-                let (bytes, reader) =
+                let (bytes, reader) = PackBitsReader::new(
-                    PackBitsReader::new(&mut self.reader, order, usize::try_from(length)?)?;
+                    &mut self.reader,
+                    order,
+                    usize::try_from(length)?,
+                )?;
                 (bytes, Box::new(reader))
             }
             CompressionMethod::OldDeflate => {
-                let (bytes, reader) =
+                let (bytes, reader) = DeflateReader::new(&mut self.reader, max_uncompressed_length)?;
-                    DeflateReader::new(&mut self.reader, max_uncompressed_length)?;
                 (bytes, Box::new(reader))
             }
             method => {
@@ -699,7 +685,9 @@ impl<R: Read + Seek> Decoder<R> {
 
     /// Number of strips in image
     pub fn strip_count(&mut self) -> TiffResult<u32> {
-        let rows_per_strip = self.get_tag_u32(Tag::RowsPerStrip).unwrap_or(self.height);
+        let rows_per_strip = self
+            .get_tag_u32(Tag::RowsPerStrip)
+            .unwrap_or(self.height);
 
         if rows_per_strip == 0 {
             return Ok(0);
@@ -745,8 +733,9 @@ impl<R: Read + Seek> Decoder<R> {
                 TiffFormatError::InconsistentSizesEncountered,
             ))?;
 
-        let rows_per_strip =
+        let rows_per_strip = usize::try_from(self
-            usize::try_from(self.get_tag_u32(Tag::RowsPerStrip).unwrap_or(self.height))?;
+            .get_tag_u32(Tag::RowsPerStrip)
+            .unwrap_or(self.height))?;
 
         let strip_height = cmp::min(
             rows_per_strip,
@@ -755,9 +744,7 @@ impl<R: Read + Seek> Decoder<R> {
 
         let buffer_size = usize::try_from(self.width)? * strip_height * self.bits_per_sample.len();
 
-        if buffer.len() < buffer_size
+        if buffer.len() < buffer_size {
-            || usize::try_from(byte_count)? / buffer.byte_len() > buffer_size
-        {
             return Err(TiffError::FormatError(
                 TiffFormatError::InconsistentSizesEncountered,
             ));
@@ -805,9 +792,11 @@ impl<R: Read + Seek> Decoder<R> {
             n if n <= 16 => DecodingResult::new_u16(buffer_size, &self.limits),
             n if n <= 32 => DecodingResult::new_u32(buffer_size, &self.limits),
             n if n <= 64 => DecodingResult::new_u64(buffer_size, &self.limits),
-            n => Err(TiffError::UnsupportedError(
+            n => {
+                Err(TiffError::UnsupportedError(
                     TiffUnsupportedError::UnsupportedBitsPerChannel(n),
-            )),
+                ))
+            }
         }
     }
 
@@ -816,8 +805,9 @@ impl<R: Read + Seek> Decoder<R> {
         self.initialize_strip_decoder()?;
         let index = self.strip_decoder.as_ref().unwrap().strip_index;
 
-        let rows_per_strip =
+        let rows_per_strip = usize::try_from(self
-            usize::try_from(self.get_tag_u32(Tag::RowsPerStrip).unwrap_or(self.height))?;
+            .get_tag_u32(Tag::RowsPerStrip)
+            .unwrap_or(self.height))?;
 
         let strip_height = cmp::min(
             rows_per_strip,
@@ -834,8 +824,9 @@ impl<R: Read + Seek> Decoder<R> {
     /// Decodes the entire image and return it as a Vector
     pub fn read_image(&mut self) -> TiffResult<DecodingResult> {
         self.initialize_strip_decoder()?;
-        let rows_per_strip =
+        let rows_per_strip = usize::try_from(self
-            usize::try_from(self.get_tag_u32(Tag::RowsPerStrip).unwrap_or(self.height))?;
+            .get_tag_u32(Tag::RowsPerStrip)
+            .unwrap_or(self.height))?;
 
         let samples_per_strip =
             usize::try_from(self.width)? * rows_per_strip * self.bits_per_sample.len();

src/encoder/mod.rs

@@ -4,8 +4,8 @@ use std::convert::TryFrom;
 use std::io::{Seek, Write};
 use std::mem;
 
-use error::{TiffError, TiffFormatError, TiffResult};
 use tags::{self, ResolutionUnit, Tag, Type};
+use error::{TiffError, TiffFormatError, TiffResult};
 
 pub mod colortype;
 mod writer;
@@ -61,7 +61,8 @@ impl TiffValue for [i8] {
 
     fn write<W: Write>(&self, writer: &mut TiffWriter<W>) -> TiffResult<()> {
         // We write using nativeedian so this should be safe
-        let slice = unsafe { ::std::slice::from_raw_parts(self.as_ptr() as *const u8, self.len()) };
+        let slice =
+            unsafe { ::std::slice::from_raw_parts(self.as_ptr() as *const u8, self.len()) };
         writer.write_bytes(slice)?;
         Ok(())
     }
@@ -94,12 +95,8 @@ impl TiffValue for [i16] {
 
     fn write<W: Write>(&self, writer: &mut TiffWriter<W>) -> TiffResult<()> {
         // We write using nativeedian so this should be safe
-        let slice = unsafe {
+        let slice =
-            ::std::slice::from_raw_parts(
+            unsafe { ::std::slice::from_raw_parts(self.as_ptr() as *const u8, self.len() * Self::BYTE_LEN as usize) };
-                self.as_ptr() as *const u8,
-                self.len() * Self::BYTE_LEN as usize,
-            )
-        };
         writer.write_bytes(slice)?;
         Ok(())
     }
@@ -132,12 +129,8 @@ impl TiffValue for [i32] {
 
     fn write<W: Write>(&self, writer: &mut TiffWriter<W>) -> TiffResult<()> {
         // We write using nativeedian so this should be safe
-        let slice = unsafe {
+        let slice =
-            ::std::slice::from_raw_parts(
+            unsafe { ::std::slice::from_raw_parts(self.as_ptr() as *const u8, self.len() * Self::BYTE_LEN as usize) };
-                self.as_ptr() as *const u8,
-                self.len() * Self::BYTE_LEN as usize,
-            )
-        };
         writer.write_bytes(slice)?;
         Ok(())
     }
@@ -414,20 +407,14 @@ impl<W: Write + Seek> TiffEncoder<W> {
     where
         [C::Inner]: TiffValue,
     {
-        let num_pix = usize::try_from(width)?
+        let num_pix = usize::try_from(width)?.checked_mul(usize::try_from(height)?)
-            .checked_mul(usize::try_from(height)?)
+            .ok_or_else(|| ::std::io::Error::new(
-            .ok_or_else(|| {
-                ::std::io::Error::new(
                 ::std::io::ErrorKind::InvalidInput,
-                    "Image width * height exceeds usize",
+                "Image width * height exceeds usize"))?;
-                )
-            })?;
         if data.len() < num_pix {
             return Err(::std::io::Error::new(
                 ::std::io::ErrorKind::InvalidData,
-                "Input data slice is undersized for provided dimensions",
+                "Input data slice is undersized for provided dimensions").into());
-            )
-            .into());
         }
 
         let encoder = DirectoryEncoder::new(&mut self.writer)?;
@@ -477,10 +464,8 @@ impl<'a, W: 'a + Write + Seek> DirectoryEncoder<'a, W> {
             value.write(&mut writer)?;
         }
 
-        self.ifd.insert(
+        self.ifd
-            tag.to_u16(),
+            .insert(tag.to_u16(), (<T>::FIELD_TYPE.to_u16(), value.count(), bytes));
-            (<T>::FIELD_TYPE.to_u16(), value.count(), bytes),
-        );
 
         Ok(())
     }
@@ -612,10 +597,7 @@ impl<'a, W: 'a + Write + Seek, T: ColorType> ImageEncoder<'a, W, T> {
 
         encoder.write_tag(Tag::RowsPerStrip, u32::try_from(rows_per_strip)?)?;
 
-        encoder.write_tag(
+        encoder.write_tag(Tag::SamplesPerPixel, u16::try_from(<T>::BITS_PER_SAMPLE.len())?)?;
-            Tag::SamplesPerPixel,
-            u16::try_from(<T>::BITS_PER_SAMPLE.len())?,
-        )?;
         encoder.write_tag(Tag::XResolution, Rational { n: 1, d: 1 })?;
         encoder.write_tag(Tag::YResolution, Rational { n: 1, d: 1 })?;
         encoder.write_tag(Tag::ResolutionUnit, ResolutionUnit::None.to_u16())?;
@@ -640,8 +622,7 @@ impl<'a, W: 'a + Write + Seek, T: ColorType> ImageEncoder<'a, W, T> {
             return 0;
         }
 
-        let start_row =
+        let start_row = ::std::cmp::min(u64::from(self.height), self.strip_idx * self.rows_per_strip);
-            ::std::cmp::min(u64::from(self.height), self.strip_idx * self.rows_per_strip);
         let end_row = ::std::cmp::min(
             u64::from(self.height),
             (self.strip_idx + 1) * self.rows_per_strip,
@@ -660,9 +641,7 @@ impl<'a, W: 'a + Write + Seek, T: ColorType> ImageEncoder<'a, W, T> {
         if u64::try_from(value.len())? != samples {
             return Err(::std::io::Error::new(
                 ::std::io::ErrorKind::InvalidData,
-                "Slice is wrong size for strip",
+                "Slice is wrong size for strip").into());
-            )
-            .into());
         }
 
         let offset = self.encoder.write_data(value)?;
@@ -675,20 +654,14 @@ impl<'a, W: 'a + Write + Seek, T: ColorType> ImageEncoder<'a, W, T> {
 
     /// Set image resolution
     pub fn resolution(&mut self, unit: ResolutionUnit, value: Rational) {
-        self.encoder
+        self.encoder.write_tag(Tag::ResolutionUnit, unit.to_u16()).unwrap();
-            .write_tag(Tag::ResolutionUnit, unit.to_u16())
+        self.encoder.write_tag(Tag::XResolution, value.clone()).unwrap();
-            .unwrap();
-        self.encoder
-            .write_tag(Tag::XResolution, value.clone())
-            .unwrap();
         self.encoder.write_tag(Tag::YResolution, value).unwrap();
     }
 
     /// Set image resolution unit
     pub fn resolution_unit(&mut self, unit: ResolutionUnit) {
-        self.encoder
+        self.encoder.write_tag(Tag::ResolutionUnit, unit.to_u16()).unwrap();
-            .write_tag(Tag::ResolutionUnit, unit.to_u16())
-            .unwrap();
     }
 
     /// Set image x-resolution

src/encoder/writer.rs

@@ -1,5 +1,5 @@
-use byteorder::{BigEndian, ByteOrder, LittleEndian, NativeEndian, WriteBytesExt};
 use error::TiffResult;
+use byteorder::{BigEndian, ByteOrder, LittleEndian, NativeEndian, WriteBytesExt};
 use std::io::{self, Seek, SeekFrom, Write};
 
 pub trait TiffByteOrder: ByteOrder {

src/error.rs

@@ -3,9 +3,9 @@ use std::fmt;
 use std::io;
 use std::string;
 
-use decoder::ifd::Value;
+use decoder::ifd::{Value};
-use miniz_oxide::inflate::TINFLStatus;
 use tags::{CompressionMethod, PhotometricInterpretation, PlanarConfiguration, Tag};
+use miniz_oxide::inflate::TINFLStatus;
 use ColorType;
 
 /// Tiff error kinds.
@@ -62,9 +62,8 @@ impl fmt::Display for TiffFormatError {
             ImageFileDirectoryNotFound => write!(fmt, "Image file directory not found."),
             InconsistentSizesEncountered => write!(fmt, "Inconsistent sizes encountered."),
             InvalidTag => write!(fmt, "Image contains invalid tag."),
-            InvalidTagValueType(ref tag) => {
+            InvalidTagValueType(ref tag) =>
-                write!(fmt, "Tag `{:?}` did not have the expected value type.", tag)
+                write!(fmt, "Tag `{:?}` did not have the expected value type.", tag),
-            }
             RequiredTagNotFound(ref tag) => write!(fmt, "Required tag `{:?}` not found.", tag),
             UnknownPredictor(ref predictor) => {
                 write!(fmt, "Unknown predictor “{}” encountered", predictor)

src/tags.rs

@@ -131,6 +131,7 @@ pub enum Type(u16) {
 }
 }
 
+
 tags! {
 pub enum CompressionMethod(u16) {
     None = 1,

tests/decode_images.rs

@@ -21,7 +21,7 @@ macro_rules! test_image_sum {
                 DecodingResult::$buffer(res) => {
                     let sum: $sum_ty = res.into_iter().map(<$sum_ty>::from).sum();
                     assert_eq!(sum, expected_sum);
-                }
+                },
                 _ => panic!("Wrong bit depth"),
             }
         }
@@ -42,9 +42,7 @@ fn test_image_color_type_unsupported(file: &str, expected_type: ColorType) {
     let mut decoder = Decoder::new(img_file).expect("Cannot create decoder");
     assert_eq!(decoder.colortype().unwrap(), expected_type);
     assert!(match decoder.read_image() {
-        Err(tiff::TiffError::UnsupportedError(
+        Err(tiff::TiffError::UnsupportedError(tiff::TiffUnsupportedError::UnsupportedColorType(_))) => true,
-            tiff::TiffUnsupportedError::UnsupportedColorType(_),
-        )) => true,
         _ => false,
     });
 }
@@ -151,6 +149,12 @@ fn test_decode_data() {
     }
 }
 
+#[test]
+fn issue_69() {
+    test_image_sum_u16("issue_69_lzw.tiff", ColorType::Gray(16), 1015486);
+    test_image_sum_u16("issue_69_packbits.tiff", ColorType::Gray(16), 1015486);
+}
+
 // TODO: GrayA support
 //#[test]
 //fn test_gray_alpha_u8()

tests/encode_images.rs

@@ -1,9 +1,9 @@
 extern crate tiff;
 
 use tiff::decoder::{Decoder, DecodingResult};
-use tiff::encoder::{colortype, SRational, TiffEncoder};
+use tiff::encoder::{colortype, TiffEncoder, SRational};
-use tiff::tags::Tag;
 use tiff::ColorType;
+use tiff::tags::Tag;
 
 use std::fs::File;
 use std::io::{Cursor, Seek, SeekFrom};
@@ -58,10 +58,7 @@ const TEST_IMAGE_DIR: &str = "./tests/images/";
 
 macro_rules! test_roundtrip {
     ($name:ident, $buffer:ident, $buffer_ty:ty) => {
-        fn $name<C: colortype::ColorType<Inner = $buffer_ty>>(
+        fn $name<C: colortype::ColorType<Inner=$buffer_ty>>(file: &str, expected_type: ColorType) {
-            file: &str,
-            expected_type: ColorType,
-        ) {
             let path = PathBuf::from(TEST_IMAGE_DIR).join(file);
             let img_file = File::open(path).expect("Cannot find test image!");
             let mut decoder = Decoder::new(img_file).expect("Cannot create decoder");
@@ -77,7 +74,8 @@ macro_rules! test_roundtrip {
                 let mut tiff = TiffEncoder::new(&mut file).unwrap();
 
                 let (width, height) = decoder.dimensions().unwrap();
-                tiff.write_image::<C>(width, height, &image_data).unwrap();
+                tiff.write_image::<C>(width, height, &image_data)
+                    .unwrap();
             }
             file.seek(SeekFrom::Start(0)).unwrap();
             {
@@ -157,64 +155,21 @@ fn test_multiple_byte() {
         let encoder = image_encoder.encoder();
 
         encoder.write_tag(Tag::Unknown(65000), &[1_u8][..]).unwrap();
-        encoder
+        encoder.write_tag(Tag::Unknown(65001), &[1_u8, 2][..]).unwrap();
-            .write_tag(Tag::Unknown(65001), &[1_u8, 2][..])
+        encoder.write_tag(Tag::Unknown(65002), &[1_u8, 2, 3][..]).unwrap();
-            .unwrap();
+        encoder.write_tag(Tag::Unknown(65003), &[1_u8, 2, 3, 4][..]).unwrap();
-        encoder
+        encoder.write_tag(Tag::Unknown(65004), &[1_u8, 2, 3, 4, 5][..]).unwrap();
-            .write_tag(Tag::Unknown(65002), &[1_u8, 2, 3][..])
-            .unwrap();
-        encoder
-            .write_tag(Tag::Unknown(65003), &[1_u8, 2, 3, 4][..])
-            .unwrap();
-        encoder
-            .write_tag(Tag::Unknown(65004), &[1_u8, 2, 3, 4, 5][..])
-            .unwrap();
     }
 
     data.set_position(0);
     {
         let mut decoder = Decoder::new(&mut data).unwrap();
 
-        assert_eq!(
+        assert_eq!(decoder.get_tag(Tag::Unknown(65000)).unwrap().into_u32_vec().unwrap(), [1]);
-            decoder
+        assert_eq!(decoder.get_tag(Tag::Unknown(65001)).unwrap().into_u32_vec().unwrap(), [1, 2]);
-                .get_tag(Tag::Unknown(65000))
+        assert_eq!(decoder.get_tag(Tag::Unknown(65002)).unwrap().into_u32_vec().unwrap(), [1, 2, 3]);
-                .unwrap()
+        assert_eq!(decoder.get_tag(Tag::Unknown(65003)).unwrap().into_u32_vec().unwrap(), [1, 2, 3, 4]);
-                .into_u32_vec()
+        assert_eq!(decoder.get_tag(Tag::Unknown(65004)).unwrap().into_u32_vec().unwrap(), [1, 2, 3, 4, 5]);
-                .unwrap(),
-            [1]
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65001))
-                .unwrap()
-                .into_u32_vec()
-                .unwrap(),
-            [1, 2]
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65002))
-                .unwrap()
-                .into_u32_vec()
-                .unwrap(),
-            [1, 2, 3]
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65003))
-                .unwrap()
-                .into_u32_vec()
-                .unwrap(),
-            [1, 2, 3, 4]
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65004))
-                .unwrap()
-                .into_u32_vec()
-                .unwrap(),
-            [1, 2, 3, 4, 5]
-        );
     }
 }
 
@@ -230,48 +185,23 @@ fn test_signed() {
 
         //Use the "reusable" tags section as per the TIFF6 spec
         encoder.write_tag(Tag::Unknown(65000), -1_i8).unwrap();
-        encoder
+        encoder.write_tag(Tag::Unknown(65001), &[-1_i8][..]).unwrap();
-            .write_tag(Tag::Unknown(65001), &[-1_i8][..])
+        encoder.write_tag(Tag::Unknown(65002), &[-1_i8, 2][..]).unwrap();
-            .unwrap();
+        encoder.write_tag(Tag::Unknown(65003), &[-1_i8, 2, -3][..]).unwrap();
-        encoder
+        encoder.write_tag(Tag::Unknown(65004), &[-1_i8, 2, -3, 4][..]).unwrap();
-            .write_tag(Tag::Unknown(65002), &[-1_i8, 2][..])
+        encoder.write_tag(Tag::Unknown(65005), &[-1_i8, 2, -3, 4, -5][..]).unwrap();
-            .unwrap();
-        encoder
-            .write_tag(Tag::Unknown(65003), &[-1_i8, 2, -3][..])
-            .unwrap();
-        encoder
-            .write_tag(Tag::Unknown(65004), &[-1_i8, 2, -3, 4][..])
-            .unwrap();
-        encoder
-            .write_tag(Tag::Unknown(65005), &[-1_i8, 2, -3, 4, -5][..])
-            .unwrap();
 
         encoder.write_tag(Tag::Unknown(65010), -1_i16).unwrap();
         encoder.write_tag(Tag::Unknown(65011), -1_i16).unwrap();
-        encoder
+        encoder.write_tag(Tag::Unknown(65012), &[-1_i16, 2][..]).unwrap();
-            .write_tag(Tag::Unknown(65012), &[-1_i16, 2][..])
+        encoder.write_tag(Tag::Unknown(65013), &[-1_i16, 2, -3][..]).unwrap();
-            .unwrap();
-        encoder
-            .write_tag(Tag::Unknown(65013), &[-1_i16, 2, -3][..])
-            .unwrap();
 
         encoder.write_tag(Tag::Unknown(65020), -1_i32).unwrap();
-        encoder
+        encoder.write_tag(Tag::Unknown(65021), &[-1_i32][..]).unwrap();
-            .write_tag(Tag::Unknown(65021), &[-1_i32][..])
+        encoder.write_tag(Tag::Unknown(65022), &[-1_i32, 2][..]).unwrap();
-            .unwrap();
-        encoder
-            .write_tag(Tag::Unknown(65022), &[-1_i32, 2][..])
-            .unwrap();
 
-        encoder
+        encoder.write_tag(Tag::Unknown(65030), SRational { n: -1, d: 100 }).unwrap();
-            .write_tag(Tag::Unknown(65030), SRational { n: -1, d: 100 })
+        encoder.write_tag(Tag::Unknown(65031), &[SRational { n: -1, d: 100 }, SRational { n: 2, d: 100 }][..]).unwrap();
-            .unwrap();
-        encoder
-            .write_tag(
-                Tag::Unknown(65031),
-                &[SRational { n: -1, d: 100 }, SRational { n: 2, d: 100 }][..],
-            )
-            .unwrap();
     }
 
     //Rewind the cursor for reading
@@ -279,129 +209,24 @@ fn test_signed() {
     {
         let mut decoder = Decoder::new(&mut data).unwrap();
 
-        assert_eq!(
+        assert_eq!(decoder.get_tag(Tag::Unknown(65000)).unwrap().into_i32().unwrap(), -1, );
-            decoder
+        assert_eq!(decoder.get_tag(Tag::Unknown(65001)).unwrap().into_i32_vec().unwrap(), [-1]);
-                .get_tag(Tag::Unknown(65000))
+        assert_eq!(decoder.get_tag(Tag::Unknown(65002)).unwrap().into_i32_vec().unwrap(), [-1, 2]);
-                .unwrap()
+        assert_eq!(decoder.get_tag(Tag::Unknown(65003)).unwrap().into_i32_vec().unwrap(), [-1, 2, -3]);
-                .into_i32()
+        assert_eq!(decoder.get_tag(Tag::Unknown(65004)).unwrap().into_i32_vec().unwrap(), [-1, 2, -3, 4]);
-                .unwrap(),
+        assert_eq!(decoder.get_tag(Tag::Unknown(65005)).unwrap().into_i32_vec().unwrap(), [-1, 2, -3, 4, -5], );
-            -1,
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65001))
-                .unwrap()
-                .into_i32_vec()
-                .unwrap(),
-            [-1]
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65002))
-                .unwrap()
-                .into_i32_vec()
-                .unwrap(),
-            [-1, 2]
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65003))
-                .unwrap()
-                .into_i32_vec()
-                .unwrap(),
-            [-1, 2, -3]
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65004))
-                .unwrap()
-                .into_i32_vec()
-                .unwrap(),
-            [-1, 2, -3, 4]
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65005))
-                .unwrap()
-                .into_i32_vec()
-                .unwrap(),
-            [-1, 2, -3, 4, -5],
-        );
 
-        assert_eq!(
+        assert_eq!(decoder.get_tag(Tag::Unknown(65010)).unwrap().into_i32().unwrap(), -1);
-            decoder
+        assert_eq!(decoder.get_tag(Tag::Unknown(65011)).unwrap().into_i32_vec().unwrap(), [-1]);
-                .get_tag(Tag::Unknown(65010))
+        assert_eq!(decoder.get_tag(Tag::Unknown(65012)).unwrap().into_i32_vec().unwrap(), [-1, 2]);
-                .unwrap()
+        assert_eq!(decoder.get_tag(Tag::Unknown(65013)).unwrap().into_i32_vec().unwrap(), [-1, 2, -3]);
-                .into_i32()
-                .unwrap(),
-            -1
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65011))
-                .unwrap()
-                .into_i32_vec()
-                .unwrap(),
-            [-1]
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65012))
-                .unwrap()
-                .into_i32_vec()
-                .unwrap(),
-            [-1, 2]
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65013))
-                .unwrap()
-                .into_i32_vec()
-                .unwrap(),
-            [-1, 2, -3]
-        );
 
-        assert_eq!(
+        assert_eq!(decoder.get_tag(Tag::Unknown(65020)).unwrap().into_i32().unwrap(), -1);
-            decoder
+        assert_eq!(decoder.get_tag(Tag::Unknown(65021)).unwrap().into_i32_vec().unwrap(), [-1]);
-                .get_tag(Tag::Unknown(65020))
+        assert_eq!(decoder.get_tag(Tag::Unknown(65022)).unwrap().into_i32_vec().unwrap(), [-1, 2]);
-                .unwrap()
-                .into_i32()
-                .unwrap(),
-            -1
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65021))
-                .unwrap()
-                .into_i32_vec()
-                .unwrap(),
-            [-1]
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65022))
-                .unwrap()
-                .into_i32_vec()
-                .unwrap(),
-            [-1, 2]
-        );
 
-        assert_eq!(
+        assert_eq!(decoder.get_tag(Tag::Unknown(65030)).unwrap().into_i32_vec().unwrap(), [-1, 100]);
-            decoder
+        assert_eq!(decoder.get_tag(Tag::Unknown(65031)).unwrap().into_i32_vec().unwrap(), [-1_i32, 100, 2, 100]);
-                .get_tag(Tag::Unknown(65030))
-                .unwrap()
-                .into_i32_vec()
-                .unwrap(),
-            [-1, 100]
-        );
-        assert_eq!(
-            decoder
-                .get_tag(Tag::Unknown(65031))
-                .unwrap()
-                .into_i32_vec()
-                .unwrap(),
-            [-1_i32, 100, 2, 100]
-        );
     }
 }
 
@@ -416,14 +241,10 @@ fn test_multipage_image() {
 
         // write first grayscale image (2x2 16-bit)
         let img1: Vec<u16> = [1, 2, 3, 4].to_vec();
-        img_encoder
+        img_encoder.write_image::<colortype::Gray16>(2, 2, &img1[..]).unwrap();
-            .write_image::<colortype::Gray16>(2, 2, &img1[..])
-            .unwrap();
         // write second grayscale image (3x3 8-bit)
         let img2: Vec<u8> = [9, 8, 7, 6, 5, 4, 3, 2, 1].to_vec();
-        img_encoder
+        img_encoder.write_image::<colortype::Gray8>(3, 3, &img2[..]).unwrap();
-            .write_image::<colortype::Gray8>(3, 3, &img2[..])
-            .unwrap();
     }
 
     // seek to the beginning of the file, so that it can be decoded