def decompress(points):
"""
'points' is a pcpatch in wkb
"""
# retrieve number of points in wkb pgpointcloud patch
npoints = utils.npoints_from_wkb_pcpatch(points)
hexbuffer = utils.hexdata_from_wkb_pcpatch(points)
hexbuffer += utils.hexa_signed_int32(npoints)
# uncompress
s = json.dumps(GreyhoundReadSchema().json()).replace("\\", "")
dtype = buildNumpyDescription(json.loads(s))
lazdata = bytes(hexbuffer)
arr = numpy.fromstring(lazdata, dtype=numpy.uint8)
d = Decompressor(arr, s)
output = numpy.zeros(npoints * dtype.itemsize, dtype=numpy.uint8)
decompressed = d.decompress(output)
decompressed_str = numpy.ndarray.tostring(decompressed)
# import struct
# for i in range(0, npoints):
# point = decompressed_str[dtype.itemsize*i:dtype.itemsize*(i+1)]
# x = point[0:4]
# y = point[4:8]
# z = point[8:12]
# xd = struct.unpack("i", x)
# yd = struct.unpack("i", y)
# zd = struct.unpack("i", z)
return [decompressed_str, dtype.itemsize]
def test_decompressor(self):
s = json.dumps(schema)
with open('test/compressed.bin', 'rb') as f:
data = f.read()
with open('test/uncompressed.bin', 'rb') as f:
original = f.read()
self.assertEqual(len(data), len_compressed,
"compressed file length is correct")
self.assertEqual(len(original), len_uncompressed,
"uncompressed file length is correct")
# last four bytes are the point count
compressed_point_count = struct.unpack('<L', data[-4:])[0]
uncompressed_point_count = struct.unpack('<L', original[-4:])[0]
self.assertEqual(compressed_point_count, uncompressed_point_count,
"compressed point count matches expected")
self.assertEqual(uncompressed_point_count, expected_point_count,
"uncompressed point count matches expected")
arr = np.frombuffer(data, dtype=np.uint8)
dtype = buildNumpyDescription(json.loads(s))
self.assertEqual(dtype.itemsize, 54)
d = Decompressor(arr, s)
decompressed = d.decompress(compressed_point_count)
uncompressed = np.frombuffer(original[0:-4], dtype=dtype)
self.assertEqual(uncompressed.shape[0], expected_point_count)
self.assertEqual(decompressed.shape[0], expected_point_count)
for i in range(len(uncompressed)):
self.assertEqual(uncompressed[i], decompressed[i])
def test_full_loop(self):
s = json.dumps(schema)
with open('test/uncompressed.bin', 'rb') as f:
original = f.read()
dtype = buildNumpyDescription(json.loads(s))
uncompressed = np.frombuffer(original[0:-4], dtype=dtype)
c = Compressor(s)
compressed = c.compress(uncompressed)
d = Decompressor(compressed, s)
decompressed = d.decompress(expected_point_count)
self.assertEqual(len(decompressed), len(uncompressed))
for i in range(len(decompressed)):
self.assertEqual(decompressed[i], uncompressed[i])
# confirm we can build from dtypes instead of json descriptions
_ = Compressor(dtype)
_ = Decompressor(compressed, dtype)
def test_full_loop(self):
s = json.dumps(schema)
with open('test/uncompressed.bin', 'rb') as f:
original = f.read()
dtype = buildNumpyDescription(json.loads(s))
uncompressed = np.frombuffer(original[0:-4], dtype=dtype)
c = Compressor(s)
compressed = c.compress(uncompressed)
d = Decompressor(compressed, s)
decompressed = d.decompress(expected_point_count)
self.assertEqual(len(decompressed), len(uncompressed))
for i in range(len(decompressed)):
self.assertEqual(decompressed[i], uncompressed[i])
# confirm we can build from dtypes instead of json descriptions
_ = Compressor(dtype)
_ = Decompressor(compressed, dtype)
def test_decompressor(self):
s = json.dumps(schema)
with open('test/compressed.bin', 'rb') as f:
data = f.read()
with open('test/uncompressed.bin','rb') as f:
original = f.read()
self.assertEqual(len(data),
len_compressed,
"compressed file length is correct")
self.assertEqual(len(original),
len_uncompressed,
"uncompressed file length is correct")
# last four bytes are the point count
compressed_point_count = struct.unpack('<L',data[-4:])[0]
uncompressed_point_count = struct.unpack('<L',original[-4:])[0]
self.assertEqual(compressed_point_count,
uncompressed_point_count,
"compressed point count matches expected")
self.assertEqual(uncompressed_point_count,
expected_point_count,
"uncompressed point count matches expected")
arr = np.frombuffer(data, dtype = np.uint8)
dtype = buildNumpyDescription(json.loads(s))
self.assertEqual(dtype.itemsize, 54)
d = Decompressor(arr, s)
output = np.zeros(compressed_point_count * dtype.itemsize, dtype=np.uint8)
decompressed = d.decompress(output)
uncompressed = np.frombuffer(original[0:-4], dtype = dtype)
self.assertEqual(uncompressed.shape[0], expected_point_count)
self.assertEqual(decompressed.shape[0], expected_point_count)
for i in range(len(uncompressed)):
self.assertEqual(uncompressed[i], decompressed[i])
def decompress(points, schema):
"""
Decode patch encoded with lazperf.
'points' is a pcpatch in wkb
"""
# retrieve number of points in wkb pgpointcloud patch
npoints = patch_numpoints(points)
hexbuffer = unhexlify(points[34:])
hexbuffer += hexa_signed_int32(npoints)
# uncompress
s = json.dumps(schema).replace("\\", "")
dtype = buildNumpyDescription(json.loads(s))
lazdata = bytes(hexbuffer)
arr = np.fromstring(lazdata, dtype=np.uint8)
d = Decompressor(arr, s)
output = np.zeros(npoints * dtype.itemsize, dtype=np.uint8)
decompressed = d.decompress(output)
return decompressed
def decompress(points, schema):
"""
Decode patch encoded with lazperf.
'points' is a pcpatch in wkb
"""
# retrieve number of points in wkb pgpointcloud patch
npoints = patch_numpoints(points)
hexbuffer = unhexlify(points[34:])
hexbuffer += hexa_signed_int32(npoints)
# uncompress
s = json.dumps(schema).replace("\\", "")
dtype = buildNumpyDescription(json.loads(s))
lazdata = bytes(hexbuffer)
arr = np.fromstring(lazdata, dtype=np.uint8)
d = Decompressor(arr, s)
output = np.zeros(npoints * dtype.itemsize, dtype=np.uint8)
decompressed = d.decompress(output)
return decompressed