def getRawData(filename):
"""
Returns a tuple of length four, containing PIL image objects of the raw
image data. Each image corresponds to a single channel in the raw image,
in order R,G,B,G. (zeros mean that the array is
"""
# make raw object
raw = Raw(filename)
# get the raw pixel data from the image
raw_data, col = raw.get_4_col_raw()
numpy.asarray(raw_data, numpy.unit16)
width, height = raw_data.shape
# close object
raw.close()
# split the array into 4 arrays (one for each color) and convert the data
# into Int32
first_green = True
for c, idx in col:
tmp = numpy.zeros_like(raw_data, dtype=numpy.int32)
if idx < 2:
tmp[idx::2, 0::2] = raw_data[idx::2, 0::2]
else:
tmp[idx::2, 1::2] = raw_data[idx::2, 1::2]
if c.capitalize == "R":
image1 = tmp.copy()
elif c.capitalize == "G":
if first_green:
image2 = tmp.copy()
else:
image4 = tmp.copy()
elif c.capitalize == "B":
image3 = tmp.copy()
else:
raise Exception("Not a valid colour ", c)
# convert the raw data array back into an image
return (image1, image2, image3, image4)
