Added BIL decoder

.gitignore

@@ -45,5 +45,9 @@ docs/_build
 docs/modules.rst
 docs/planetaryimage.rst
 
+# Pycharm
+.idea/
+
 # Sample Data
 tests/mission_data
+.pytest_cache/

AUTHORS.rst

@@ -13,4 +13,5 @@ Contributors
 * Trevor Olson <[email protected]>
 * Nikhil Kalige <[email protected]>
 * Austin Godber <[email protected]>
-* Bhavin Nayak <[email protected]>
+* Bhavin Nayak <[email protected]>
+* Andrew Annex <[email protected]>

planetaryimage/decoders.py

@@ -3,6 +3,9 @@
 
 
 class BandSequentialDecoder(object):
+    """
+    BSQ
+    """
     def __init__(self, dtype, shape, compression=None):
         self.dtype = dtype
         self.shape = shape
@@ -21,6 +24,34 @@ def decode(self, stream):
         return data.reshape(self.shape)
 
 
+class LineInterleavedDecoder(object):
+    """
+    BIL
+    """
+    def __init__(self, dtype, shape, compression=None):
+        self.dtype = dtype
+        self.shape = shape
+        self.sample_bytes = dtype.itemsize
+        self.compression = compression
+
+    @property
+    def size(self):
+        return numpy.product(self.shape)
+
+    def decode(self, stream):
+        bands, lines, samples = self.shape
+        bs = bands*samples
+        data = numpy.empty(self.shape, self.dtype)
+        for line in range(lines):
+            if self.compression:
+                chunk = numpy.fromstring(stream.read(bs * self.sample_bytes), self.dtype)
+            else:
+                chunk = numpy.fromfile(stream, self.dtype, bs)
+            data[:, line, :] = chunk.reshape((bands, samples))
+
+        return data
+
+
 class TileDecoder(object):
     def __init__(self, dtype, shape, tile_shape):
         self.dtype = dtype

planetaryimage/image.py

@@ -142,9 +142,10 @@ def image(self):
         """
         if self.bands == 1:
             return self.data.squeeze()
-        elif self.bands == 3:
+        elif self.bands > 1:
             return numpy.dstack(self.data)
-        # TODO: what about multiband images with 2, and 4+ bands?
+        else:
+            raise NotImplementedError('Have no impl for {} bands'.format(self.bands))
 
     @property
     def bands(self):

planetaryimage/pds3image.py

@@ -6,7 +6,7 @@
 import collections
 
 from .image import PlanetaryImage
-from .decoders import BandSequentialDecoder
+from . import decoders
 
 
 class Pointer(collections.namedtuple('Pointer', ['filename', 'bytes'])):
@@ -311,6 +311,12 @@ def record_bytes(self):
 
     @property
     def _image_pointer(self):
+        # If we have a File object containing an Image within it
+        if '^IMAGE' not in self.label and 'FILE' in self.label:
+            new_label = self.label['FILE']
+            if '^IMAGE' in new_label:
+                self.label = new_label
+                return Pointer.parse(new_label['^IMAGE'], self.record_bytes)
         return Pointer.parse(self.label['^IMAGE'], self.record_bytes)
 
     @property
@@ -343,7 +349,12 @@ def dtype(self):
     @property
     def _decoder(self):
         if self.format == 'BAND_SEQUENTIAL':
-            return BandSequentialDecoder(
+            return decoders.BandSequentialDecoder(
                 self.dtype, self.shape, self.compression
             )
+        elif self.format == 'LINE_INTERLEAVED':
+            return decoders.LineInterleavedDecoder(
+                self.dtype, self.shape, self.compression
+            )
+
         raise ValueError('Unkown format (%s)' % self.format)

tests/test_pds3file.py

@@ -14,7 +14,6 @@
 gzipped_filename = os.path.join(DATA_DIR, 'pds3_1band.IMG.gz')
 bz2_filename = os.path.join(DATA_DIR, 'pds3_1band.IMG.bz2')
 
-
 @pytest.fixture
 def expected():
     return numpy.loadtxt(os.path.join(DATA_DIR, 'pds3_1band.txt')).reshape(