Functions
def	get_packet_total_bytes (primary_header_bytes)

def	get_packet_apid (primary_header_bytes)

def	iter_packet_bytes (file, include_primary_header=True)

def	split_packet_bytes (file, include_primary_header=True)

def	read_primary_headers (file)

def	split_by_apid (mixed_file, valid_apids=None)

def	count_packets (file, return_missing_bytes=False)

Detailed Description

Utils for the CCSDSPy package.

Function Documentation

◆ count_packets()

def ccsdspy.utils.count_packets	(	file,
		return_missing_bytes = `False`
	)

Count the number of packets in a file and check if there are any
missing bytes in the last packet.

This function works with mixed files containing multiple APIDs, which may
include both fixed length and variable length packets. When used with
multiple APIDs, it simply returns the total number of packets of any APID.

If end of last packet doesn't align with end of file, a warning is issued.

Parameters
----------
file : str, file-like
  Path to file on the local file system, or file-like object
return_missing_bytes : bool, optional
  Also return the number of missing bytes at the end of the file. This
  is the number of bytes which would need to be added to the file to
  complete the last packet expected (as set by the packet length in
  the last packet's primary header).

Returns
-------
num_packets : int
   Number of complete packets in the file
missing_bytes : int, optional
  The number of bytes which would need to be added to the file to
  complete the last packet expected (as set by the packet length in
  the last packet's primary header).

Definition at line 185 of file utils.py.

◆ get_packet_apid()

def ccsdspy.utils.get_packet_apid ( primary_header_bytes )

[autogenerated]

Definition at line 21 of file utils.py.

◆ get_packet_total_bytes()

def ccsdspy.utils.get_packet_total_bytes ( primary_header_bytes )

[autogenerated]

Definition at line 15 of file utils.py.

◆ iter_packet_bytes()

def ccsdspy.utils.iter_packet_bytes	(	file,
		include_primary_header = `True`
	)

Iterate through packets as raw bytes objects, in the order they appear in a file.

This function works with mixed files containing multiple APIDs, which may
include both fixed length and variable length packets.

If end of last packet doesn't align with end of file, a warning is issued.

Parameters
----------
file : str, file-like
  Path to file on the local file system, or file-like object
include_primary_header : bool
  If set to False, excludes the primary header bytes (the first six)

Yields
------
packet_bytes : bytes
   Bytes associated with each packet as it appears in the file. When
   include_primary_header=False, the primary header bytes are excluded.

Definition at line 33 of file utils.py.

◆ read_primary_headers()

def ccsdspy.utils.read_primary_headers ( file )

Read primary header fields and return contents as a dictionary
of arrays.

This function works with mixed files containing multiple APIDs, which may
include both fixed length and variable length packets.

Parameters
----------
file : str, file-like
  Path to file on the local file system, or file-like object

Returns
-------
header_arrays : dict, string to NumPy array
   Dictionary mapping header names to NumPy arrays. The header names are:
   `CCSDS_VERSION_NUMBER`, `CCSDS_PACKET_TYPE`, `CCSDS_SECONDARY_FLAG`,
   `CCSDS_SEQUENCE_FLAG`, `CCSDS_APID`, `CCSDS_SEQUENCE_COUNT`,
   `CCSDS_PACKET_LENGTH`

Definition at line 109 of file utils.py.

◆ split_by_apid()

def ccsdspy.utils.split_by_apid	(	mixed_file,
		valid_apids = `None`
	)

Split a stream of mixed APIDs into separate streams by APID.

This works with a mix of both fixed length and variable length packets.

Parameters
----------
mixed_file: str, file-like
   Path to file on the local file system, or file-like object
valid_apids: list of int, None
   Optional list of valid APIDs. If specified, warning will be issued when
   an APID is encountered outside this list.

Returns
-------
stream_by_apid : dict, int to :py:class:`~io.BytesIO`
  Dictionary mapping integer apid number to BytesIO instance with the file
  pointer at the beginning of the stream.

Definition at line 143 of file utils.py.

◆ split_packet_bytes()

def ccsdspy.utils.split_packet_bytes	(	file,
		include_primary_header = `True`
	)

Retrieve a list of bytes objects corresponding to each packet in a file.

This function works with mixed files containing multiple APIDs, which may
include both fixed length and variable length packets.

If end of last packet doesn't align with end of file, a warning is issued.

Parameters
----------
file : str, file-like
  Path to file on the local file system, or file-like object
include_primary_header : bool
  If set to False, excludes the primary header bytes (the first six)

Returns
-------
packet_bytes : list of bytes
   List of bytes objects associated with each packet as it appears in the
   file. When include_primary_header=False, each byte object will have its
   primary header bytes excluded.

Definition at line 84 of file utils.py.

Functions