You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 

20 lines
690 B

import struct
def read_chunk(fh, chunk_location):
"""
Gets the data for a given chunk pointer
:rtype: bytes
"""
fh.seek(chunk_location)
# The chunk metadata is always 16 bytes long
chunk_metadata = fh.read(16)
header, relative_offset, data_length = struct.unpack("IIQ", chunk_metadata)
if header != 0xabeceda:
raise ValueError("The ND2 file seems to be corrupted.")
# We start at the location of the chunk metadata, skip over the metadata, and then proceed to the
# start of the actual data field, which is at some arbitrary place after the metadata.
fh.seek(chunk_location + 16 + relative_offset)
return fh.read(data_length)