def FileReadInteger(file_handle: io.BufferedRandom,
size: int = INT_VALUE) -> int:
if size < CHAR_VALUE or size > INT_VALUE:
raise Exception("Size error")
return int.from_bytes(file_handle.read(size),
byteorder="little",
signed=False)
def FileReadString(file_handle: io.BufferedRandom, length: int = -1) -> str:
if file_handle.binflag:
if length < 1:
return ""
return file_handle.read(
len("a".encode(file_handle.encoding)) * length).decode(
file_handle.encoding)
return file_handle.readline(length)
def __init__(self, file: BufferedRandom) -> None:
"""Eine SaveFile Instanz der Generation 4
Parameter
----------------
```py
(BufferedRandom) file
```
Die geöffnete Speicherdatei
"""
self.File = file
self.data = [x for x in file.read()]
self.GeneralBlockPosition = self.GetActiveBlock(0, self.SmallBlockEnd)
self.GeneralBlockStart = self.GeneralBlockPosition * self.PartitionSize
def read(self, path, offset, size):
buf = None
br = None
conn = None
try:
conn, desc = self.session.data_objects.open(path, O_RDONLY)
raw = iRODSDataObjectFileRaw(conn, desc)
br = BufferedRandom(raw)
new_offset = br.seek(offset)
if new_offset == offset:
buf = br.read(size)
finally:
if br:
br.close()
if conn:
conn.release(True)
return buf
def read_frame_data(seekable_binary_stream: io.BufferedRandom):
seekable_binary_stream.seek(0)
header = seekable_binary_stream.read(2)
if header != b'\xff\xd8':
raise Exception
size = None
while size is None:
marker = seekable_binary_stream.read(2)
# fix marker reading position
if marker[0] != 255 and marker[1] == 255:
seekable_binary_stream.seek(-1, 1)
marker = seekable_binary_stream.read(2)
if marker == b'\xff\x00':
raise ValueError("jpeg marker not found")
if marker in START_OF_FRAME_MARKERS:
seekable_binary_stream.seek(3, 1)
size = struct.unpack('>HH', seekable_binary_stream.read(4))
components = seekable_binary_stream.read(1)[0]
component_scales = []
subsampling = SUPPORTED_COLOR_SPACES.NONE
for component in range(components):
component_id = seekable_binary_stream.read(1)[0]
colorspace_struct = seekable_binary_stream.read(1)[0]
h = (colorspace_struct & 0xf0) >> 4
v = colorspace_struct & 0x0f
component_scales.append((h, v))
seekable_binary_stream.seek(1, 1)
if component_scales[0] == (2, 2):
subsampling = SUPPORTED_COLOR_SPACES.YUV420
elif component_scales[0] == (2, 1) or component_scales[0] == (1,
2):
subsampling = SUPPORTED_COLOR_SPACES.YUV422
else:
subsampling = SUPPORTED_COLOR_SPACES.YUV444
return (size, subsampling)
else:
frame_len = struct.unpack('>H', seekable_binary_stream.read(2))[0]
seekable_binary_stream.seek(frame_len - 2, 1)
def FileReadDouble(file_handle: io.BufferedRandom) -> float:
return struct.unpack("<d", file_handle.read(8))[0]
def FileReadFloat(file_handle: io.BufferedRandom) -> float:
return struct.unpack("<f", file_handle.read(4))[0]
def FileReadLong(file_handle: io.BufferedRandom) -> int:
return int.from_bytes(file_handle.read(8),
byteorder="little",
signed=False)
