Add support for IEEEFP 32 and 64 bit encoding

src/encoder/colortype.rs

@@ -1,4 +1,4 @@
-use tags::PhotometricInterpretation;
+use tags::{PhotometricInterpretation, SampleFormat};
 
 /// Trait for different colortypes that can be encoded.
 pub trait ColorType {
@@ -8,6 +8,8 @@ pub trait ColorType {
     const TIFF_VALUE: PhotometricInterpretation;
     /// The value of the tiff tag `BitsPerSample`
     const BITS_PER_SAMPLE: &'static [u16];
+    /// The value of the tiff tag `SampleFormat`
+    const SAMPLE_FORMAT: &'static [SampleFormat];
 }
 
 pub struct Gray8;
@@ -15,6 +17,7 @@ impl ColorType for Gray8 {
     type Inner = u8;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::BlackIsZero;
     const BITS_PER_SAMPLE: &'static [u16] = &[8];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT];
 }
 
 pub struct Gray16;
@@ -22,6 +25,7 @@ impl ColorType for Gray16 {
     type Inner = u16;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::BlackIsZero;
     const BITS_PER_SAMPLE: &'static [u16] = &[16];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT];
 }
 
 pub struct Gray32;
@@ -29,6 +33,15 @@ impl ColorType for Gray32 {
     type Inner = u32;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::BlackIsZero;
     const BITS_PER_SAMPLE: &'static [u16] = &[32];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT];
+}
+
+pub struct Gray32Float;
+impl ColorType for Gray32Float {
+    type Inner = f32;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::BlackIsZero;
+    const BITS_PER_SAMPLE: &'static [u16] = &[32];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::IEEEFP];
 }
 
 pub struct Gray64;
@@ -36,6 +49,15 @@ impl ColorType for Gray64 {
     type Inner = u64;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::BlackIsZero;
     const BITS_PER_SAMPLE: &'static [u16] = &[64];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT];
+}
+
+pub struct Gray64Float;
+impl ColorType for Gray64Float {
+    type Inner = f64;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::BlackIsZero;
+    const BITS_PER_SAMPLE: &'static [u16] = &[64];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::IEEEFP];
 }
 
 pub struct RGB8;
@@ -43,6 +65,7 @@ impl ColorType for RGB8 {
     type Inner = u8;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
     const BITS_PER_SAMPLE: &'static [u16] = &[8, 8, 8];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT; 3];
 }
 
 pub struct RGB16;
@@ -50,6 +73,7 @@ impl ColorType for RGB16 {
     type Inner = u16;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
     const BITS_PER_SAMPLE: &'static [u16] = &[16, 16, 16];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT; 3];
 }
 
 pub struct RGB32;
@@ -57,6 +81,15 @@ impl ColorType for RGB32 {
     type Inner = u32;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
     const BITS_PER_SAMPLE: &'static [u16] = &[32, 32, 32];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT; 3];
+}
+
+pub struct RGB32Float;
+impl ColorType for RGB32Float {
+    type Inner = f32;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
+    const BITS_PER_SAMPLE: &'static [u16] = &[32, 32, 32];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::IEEEFP; 3];
 }
 
 pub struct RGB64;
@@ -64,6 +97,15 @@ impl ColorType for RGB64 {
     type Inner = u64;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
     const BITS_PER_SAMPLE: &'static [u16] = &[64, 64, 64];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT; 3];
+}
+
+pub struct RGB64Float;
+impl ColorType for RGB64Float {
+    type Inner = f64;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
+    const BITS_PER_SAMPLE: &'static [u16] = &[64, 64, 64];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::IEEEFP; 3];
 }
 
 pub struct RGBA8;
@@ -71,6 +113,7 @@ impl ColorType for RGBA8 {
     type Inner = u8;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
     const BITS_PER_SAMPLE: &'static [u16] = &[8, 8, 8, 8];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT; 4];
 }
 
 pub struct RGBA16;
@@ -78,6 +121,7 @@ impl ColorType for RGBA16 {
     type Inner = u16;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
     const BITS_PER_SAMPLE: &'static [u16] = &[16, 16, 16, 16];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT; 4];
 }
 
 pub struct RGBA32;
@@ -85,6 +129,15 @@ impl ColorType for RGBA32 {
     type Inner = u32;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
     const BITS_PER_SAMPLE: &'static [u16] = &[32, 32, 32, 32];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT; 4];
+}
+
+pub struct RGBA32Float;
+impl ColorType for RGBA32Float {
+    type Inner = f32;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
+    const BITS_PER_SAMPLE: &'static [u16] = &[32, 32, 32, 32];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::IEEEFP; 4];
 }
 
 pub struct RGBA64;
@@ -92,6 +145,15 @@ impl ColorType for RGBA64 {
     type Inner = u64;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
     const BITS_PER_SAMPLE: &'static [u16] = &[64, 64, 64, 64];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT; 4];
+}
+
+pub struct RGBA64Float;
+impl ColorType for RGBA64Float {
+    type Inner = f64;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
+    const BITS_PER_SAMPLE: &'static [u16] = &[64, 64, 64, 64];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::IEEEFP; 4];
 }
 
 pub struct CMYK8;
@@ -99,6 +161,7 @@ impl ColorType for CMYK8 {
     type Inner = u8;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::CMYK;
     const BITS_PER_SAMPLE: &'static [u16] = &[8, 8, 8, 8];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT; 4];
 }
 
 pub struct CMYK16;
@@ -106,6 +169,7 @@ impl ColorType for CMYK16 {
     type Inner = u16;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::CMYK;
     const BITS_PER_SAMPLE: &'static [u16] = &[16, 16, 16, 16];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT; 4];
 }
 
 pub struct CMYK32;
@@ -113,6 +177,15 @@ impl ColorType for CMYK32 {
     type Inner = u32;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::CMYK;
     const BITS_PER_SAMPLE: &'static [u16] = &[32, 32, 32, 32];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT; 4];
+}
+
+pub struct CMYK32Float;
+impl ColorType for CMYK32Float {
+    type Inner = f32;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::CMYK;
+    const BITS_PER_SAMPLE: &'static [u16] = &[32, 32, 32, 32];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::IEEEFP; 4];
 }
 
 pub struct CMYK64;
@@ -120,4 +193,13 @@ impl ColorType for CMYK64 {
     type Inner = u64;
     const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::CMYK;
     const BITS_PER_SAMPLE: &'static [u16] = &[64, 64, 64, 64];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::UINT; 4];
+}
+
+pub struct CMYK64Float;
+impl ColorType for CMYK64Float {
+    type Inner = f64;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::CMYK;
+    const BITS_PER_SAMPLE: &'static [u16] = &[64, 64, 64, 64];
+    const SAMPLE_FORMAT: &'static [SampleFormat] = &[SampleFormat::IEEEFP; 4];
 }

src/encoder/mod.rs

@@ -153,6 +153,40 @@ impl TiffValue for [u64] {
     }
 }
 
+impl TiffValue for [f32] {
+    const BYTE_LEN: u32 = 4;
+    const FIELD_TYPE: Type = Type::FLOAT;
+
+    fn count(&self) -> u32 {
+        self.len() as u32
+    }
+
+    fn write<W: Write>(&self, writer: &mut TiffWriter<W>) -> TiffResult<()> {
+        // We write using nativeedian so this sould be safe
+        let slice =
+            unsafe { ::std::slice::from_raw_parts(self.as_ptr() as *const u8, self.len() * 4) };
+        writer.write_bytes(slice)?;
+        Ok(())
+    }
+}
+
+impl TiffValue for [f64] {
+    const BYTE_LEN: u32 = 8;
+    const FIELD_TYPE: Type = Type::DOUBLE;
+
+    fn count(&self) -> u32 {
+        self.len() as u32
+    }
+
+    fn write<W: Write>(&self, writer: &mut TiffWriter<W>) -> TiffResult<()> {
+        // We write using nativeedian so this sould be safe
+        let slice =
+            unsafe { ::std::slice::from_raw_parts(self.as_ptr() as *const u8, self.len() * 8) };
+        writer.write_bytes(slice)?;
+        Ok(())
+    }
+}
+
 impl TiffValue for [Rational] {
     const BYTE_LEN: u32 = 8;
     const FIELD_TYPE: Type = Type::RATIONAL;
@@ -283,6 +317,34 @@ impl TiffValue for u64 {
     }
 }
 
+impl TiffValue for f32 {
+    const BYTE_LEN: u32 = 4;
+    const FIELD_TYPE: Type = Type::FLOAT;
+
+    fn count(&self) -> u32 {
+        1
+    }
+
+    fn write<W: Write>(&self, writer: &mut TiffWriter<W>) -> TiffResult<()> {
+        writer.write_f32(*self)?;
+        Ok(())
+    }
+}
+
+impl TiffValue for f64 {
+    const BYTE_LEN: u32 = 8;
+    const FIELD_TYPE: Type = Type::DOUBLE;
+
+    fn count(&self) -> u32 {
+        1
+    }
+
+    fn write<W: Write>(&self, writer: &mut TiffWriter<W>) -> TiffResult<()> {
+        writer.write_f64(*self)?;
+        Ok(())
+    }
+}
+
 impl TiffValue for Rational {
     const BYTE_LEN: u32 = 8;
     const FIELD_TYPE: Type = Type::RATIONAL;
@@ -593,6 +655,8 @@ impl<'a, W: 'a + Write + Seek, T: ColorType> ImageEncoder<'a, W, T> {
         encoder.write_tag(Tag::Compression, tags::CompressionMethod::None.to_u16())?;
 
         encoder.write_tag(Tag::BitsPerSample, <T>::BITS_PER_SAMPLE)?;
+        let sample_format: Vec<_> = <T>::SAMPLE_FORMAT.iter().map(|s| s.to_u16()).collect();
+        encoder.write_tag(Tag::SampleFormat, &sample_format[..])?;
         encoder.write_tag(Tag::PhotometricInterpretation, <T>::TIFF_VALUE.to_u16())?;
 
         encoder.write_tag(Tag::RowsPerStrip, u32::try_from(rows_per_strip)?)?;

src/encoder/writer.rs

@@ -93,6 +93,20 @@ impl<W: Write> TiffWriter<W> {
         Ok(())
     }
 
+    pub fn write_f32(&mut self, n: f32) -> Result<(), io::Error> {
+        self.writer.write_f32::<NativeEndian>(n)?;
+        self.offset += 4;
+
+        Ok(())
+    }
+
+    pub fn write_f64(&mut self, n: f64) -> Result<(), io::Error> {
+        self.writer.write_f64::<NativeEndian>(n)?;
+        self.offset += 8;
+
+        Ok(())
+    }
+
     pub fn pad_word_boundary(&mut self) -> Result<(), io::Error> {
         if self.offset % 4 != 0 {
             let padding = [0, 0, 0];

src/tags.rs

@@ -127,6 +127,8 @@ pub enum Type(u16) {
     SSHORT = 8,
     SLONG = 9,
     SRATIONAL = 10,
+    FLOAT = 11,
+    DOUBLE = 12,
     /// BigTIFF 64-bit unsigned integer
     LONG8 = 16,
 }

tests/encode_images.rs

@@ -94,6 +94,8 @@ test_roundtrip!(test_u8_roundtrip, U8, u8);
 test_roundtrip!(test_u16_roundtrip, U16, u16);
 test_roundtrip!(test_u32_roundtrip, U32, u32);
 test_roundtrip!(test_u64_roundtrip, U64, u64);
+test_roundtrip!(test_f32_roundtrip, F32, f32);
+test_roundtrip!(test_f64_roundtrip, F64, f64);
 
 #[test]
 fn test_gray_u8_roundtrip() {
@@ -145,6 +147,26 @@ fn test_rgb_u64_roundtrip() {
     test_u64_roundtrip::<colortype::RGB64>("gradient-3c-64b.tiff", ColorType::RGB(64));
 }
 
+#[test]
+fn test_gray_f32_roundtrip() {
+    test_f32_roundtrip::<colortype::Gray32Float>("gradient-1c-32b-float.tiff", ColorType::Gray(32));
+}
+
+#[test]
+fn test_rgb_f32_roundtrip() {
+    test_f32_roundtrip::<colortype::RGB32Float>("gradient-3c-32b-float.tiff", ColorType::RGB(32));
+}
+
+#[test]
+fn test_cmyk_f32_roundtrip() {
+    test_f32_roundtrip::<colortype::CMYK32Float>("cmyk-3c-32b-float.tiff", ColorType::CMYK(32));
+}
+
+#[test]
+fn test_gray_f64_roundtrip() {
+    test_f64_roundtrip::<colortype::Gray64Float>("gradient-1c-64b-float.tiff", ColorType::Gray(64));
+}
+
 #[test]
 fn test_multiple_byte() {
     let mut data = Cursor::new(Vec::new());