Merge pull request #17 from 51systems/blackarea

Exposed masked black areas on RawImage

src/decoders/dng.rs

@@ -76,6 +76,7 @@ impl<'a> Decoder for DngDecoder<'a> {
       xyz_to_cam: try!(self.get_color_matrix()),
       cfa: if linear {CFA::new("")} else {try!(self.get_cfa(raw))},
       crops: try!(self.get_crops(raw, width, height)),
+      blackarea: self.get_masked_areas(raw),
       orientation: orientation,
     })
   }
@@ -124,6 +125,23 @@ impl<'a> DngDecoder<'a> {
     }
   }
 
+  fn get_masked_areas(&self, raw: &TiffIFD) -> Vec<(u64, u64, u64, u64)> {
+    let mut areas = Vec::new();
+
+    if let Some(masked_area) = raw.find_entry(Tag::MaskedAreas) {
+      for x in (0..masked_area.count()).step_by(4) {
+        areas.push((
+          masked_area.get_u32(x).into(),
+          masked_area.get_u32(x + 1).into(),
+          masked_area.get_u32(x + 2).into(),
+          masked_area.get_u32(x + 3).into()
+        ));
+      }
+    }
+
+    areas
+  }
+
   fn get_color_matrix(&self) -> Result<[[f32;3];4],String> {
     let mut matrix: [[f32;3];4] = [[0.0;3];4];
     let cmatrix = {

src/decoders/image.rs

@@ -31,6 +31,11 @@ pub struct RawImage {
   pub cfa: CFA,
   /// how much to crop the image to get all the usable area, order is top, right, bottom, left
   pub crops: [usize;4],
+
+  /// Areas of the sensor that is masked to prevent it from receiving light. Used to calculate
+  /// black levels and noise. Each tuple represents a masked rectangle's top, right, bottom, left
+  pub blackarea: Vec<(u64,u64,u64,u64)>,
+
   /// orientation of the image as indicated by the image metadata
   pub orientation: Orientation,
   /// image data itself, has width*height*cpp elements
@@ -73,6 +78,19 @@ impl RawImage {
       camera.blacklevels
     };
 
+    // tuple format is top, right, bottom left
+    let mut blackarea: Vec<(u64,u64,u64,u64)> = Vec::new();
+
+    if camera.blackareah.1 != 0 {
+        blackarea.push((camera.blackareah.0 as u64, width as u64,
+                        (camera.blackareah.0 + camera.blackareah.1) as u64, 0));
+    }
+
+    if camera.blackareav.1 != 0 {
+        blackarea.push((0, (camera.blackareav.0 + camera.blackareav.1) as u64,
+                        height as u64, camera.blackareav.0 as u64))
+    }
+
     RawImage {
       make: camera.make.clone(),
       model: camera.model.clone(),
@@ -88,6 +106,7 @@ impl RawImage {
       xyz_to_cam: camera.xyz_to_cam,
       cfa: camera.cfa.clone(),
       crops: camera.crops,
+      blackarea: blackarea,
       orientation: camera.orientation,
     }
   }

src/decoders/raf.rs

@@ -80,6 +80,7 @@ impl<'a> Decoder for RafDecoder<'a> {
         xyz_to_cam: camera.xyz_to_cam,
         cfa: camera.cfa.clone(),
         crops: [0,0,0,0],
+        blackarea: Vec::new(),
         orientation: camera.orientation,
       })
     } else {

src/decoders/tiff.rs

@@ -81,6 +81,7 @@ pub enum Tag {
   DNGPrivateArea   = 0xC634,
   Cr2StripeWidths  = 0xC640,
   ActiveArea       = 0xC68D,
+  MaskedAreas      = 0xC68E,
   RafRawSubIFD     = 0xF000,
   RafImageWidth    = 0xF001,
   RafImageLength   = 0xF002,