Merge pull request #23 from birktj/encode

Tiff encoding

Cargo.toml

@@ -19,3 +19,6 @@ byteorder = "1.2"
 lzw = "0.10"
 num-derive = "0.2"
 num-traits = "0.2"
+
+[dev-dependencies]
+tempfile = "3.0"

src/decoder/ifd.rs

@@ -26,6 +26,12 @@ macro_rules! tags {
                     Tag::Unknown(n)
                 }
             }
+            pub fn to_u16(&self) -> u16 {
+                match self {
+                    $( Tag::$tag => $val, )*
+                    Tag::Unknown(n) => *n,
+                }
+            }
         }
     }
 }

src/encoder/colortype.rs

@@ -0,0 +1,60 @@
+use crate::decoder::PhotometricInterpretation;
+
+/// Trait for different colortypes that can be encoded.
+pub trait ColorType {
+    /// The type of each sample of this colortype
+    type Inner: super::TiffValue;
+    /// The value of the tiff tag `PhotometricInterpretation`
+    const TIFF_VALUE: PhotometricInterpretation;
+    /// The value of the tiff tag `BitsPerSample`
+    const BITS_PER_SAMPLE: &'static [u16];
+}
+
+pub struct Gray8;
+impl ColorType for Gray8 {
+    type Inner = u8;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::BlackIsZero;
+    const BITS_PER_SAMPLE: &'static [u16] = &[8];
+}
+
+pub struct Gray16;
+impl ColorType for Gray16 {
+    type Inner = u16;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::BlackIsZero;
+    const BITS_PER_SAMPLE: &'static [u16] = &[16];
+}
+
+pub struct RGB8;
+impl ColorType for RGB8 {
+    type Inner = u8;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
+    const BITS_PER_SAMPLE: &'static [u16] = &[8, 8, 8];
+}
+
+pub struct RGB16;
+impl ColorType for RGB16 {
+    type Inner = u16;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
+    const BITS_PER_SAMPLE: &'static [u16] = &[16, 16, 16];
+}
+
+pub struct RGBA8;
+impl ColorType for RGBA8 {
+    type Inner = u8;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
+    const BITS_PER_SAMPLE: &'static [u16] = &[8, 8, 8, 8];
+}
+
+pub struct RGBA16;
+impl ColorType for RGBA16 {
+    type Inner = u16;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::RGB;
+    const BITS_PER_SAMPLE: &'static [u16] = &[16, 16, 16, 16];
+}
+
+pub struct CMYK8;
+impl ColorType for CMYK8 {
+    type Inner = u8;
+    const TIFF_VALUE: PhotometricInterpretation = PhotometricInterpretation::CMYK;
+    const BITS_PER_SAMPLE: &'static [u16] = &[8, 8, 8, 8];
+}