BW3-Core/boswatch/decoder/pocsagDecoder.py

90 lines
2.7 KiB
Python
Raw Normal View History

2018-01-07 14:09:40 +01:00
#!/usr/bin/python
# -*- coding: utf-8 -*-
r"""!
2018-01-07 14:09:40 +01:00
____ ____ ______ __ __ __ _____
/ __ )/ __ \/ ___/ | / /___ _/ /______/ /_ |__ /
/ __ / / / /\__ \| | /| / / __ `/ __/ ___/ __ \ /_ <
/ /_/ / /_/ /___/ /| |/ |/ / /_/ / /_/ /__/ / / / ___/ /
/_____/\____//____/ |__/|__/\__,_/\__/\___/_/ /_/ /____/
German BOS Information Script
by Bastian Schroll
@file: pocsag.py
@date: 06.01.2018
@author: Bastian Schroll
@description: Decoder class for pocsag
"""
import logging
import re
2019-03-01 12:16:06 +01:00
from boswatch.packet import Packet
2018-01-07 14:09:40 +01:00
logging.debug("- %s loaded", __name__)
2018-09-09 16:17:49 +02:00
class PocsagDecoder:
r"""!POCSAG decoder class
2018-01-07 14:09:40 +01:00
This class decodes POCSAG data.
2018-02-03 22:32:28 +01:00
First step is to validate the data and _check if the format is correct.
2018-01-07 14:09:40 +01:00
In the last step a valid BOSWatch packet is created and returned"""
2018-01-08 07:56:10 +01:00
@staticmethod
2018-01-08 07:58:33 +01:00
def decode(data):
r"""!Decodes POCSAG
2018-01-07 14:09:40 +01:00
@param data: POCSAG for decoding
@return BOSWatch POCSAG packet or None"""
2018-09-09 16:17:49 +02:00
bitrate, ric, subric = PocsagDecoder._getBitrateRicSubric(data)
2018-01-07 14:09:40 +01:00
2018-01-08 08:09:23 +01:00
if re.search("[0-9]{7}", ric) and re.search("[1-4]", subric):
2018-01-07 14:09:40 +01:00
if "Alpha:" in data:
message = data.split('Alpha:')[1].strip()
2018-01-08 08:09:23 +01:00
message = message.replace('<NUL>', '').replace('<NUL', '').replace('< NUL>', '').replace('<EOT>', '').strip()
2018-01-07 14:09:40 +01:00
else:
message = ""
subricText = subric.replace("1", "a").replace("2", "b").replace("3", "c").replace("4", "d")
logging.debug("found valid POCSAG")
2019-03-01 12:16:06 +01:00
bwPacket = Packet()
2018-01-09 11:33:23 +01:00
bwPacket.set("mode", "pocsag")
bwPacket.set("bitrate", bitrate)
bwPacket.set("ric", ric)
bwPacket.set("subric", subric)
bwPacket.set("subricText", subricText)
bwPacket.set("message", message)
2018-01-07 14:09:40 +01:00
return bwPacket
2019-10-26 18:56:14 +02:00
logging.warning("no valid POCSAG")
2018-01-07 14:09:40 +01:00
return None
2018-01-08 07:56:10 +01:00
@staticmethod
def _getBitrateRicSubric(data):
r"""!Gets the Bitrate, Ric and Subric from data
2018-01-08 07:56:10 +01:00
@param data: POCSAG data string
@return bitrate
@return ric
@return subric"""
2019-09-20 17:38:33 +02:00
bitrate, ric, subric = "0", "0", "0"
2018-01-08 07:56:10 +01:00
if "POCSAG512:" in data:
2019-09-20 17:38:33 +02:00
bitrate = "512"
2018-01-08 07:56:10 +01:00
ric = data[20:27].replace(" ", "").zfill(7)
subric = str(int(data[39]) + 1)
elif "POCSAG1200:" in data:
2019-09-20 17:38:33 +02:00
bitrate = "1200"
2018-01-08 07:56:10 +01:00
ric = data[21:28].replace(" ", "").zfill(7)
subric = str(int(data[40]) + 1)
elif "POCSAG2400:" in data:
2019-09-20 17:38:33 +02:00
bitrate = "2400"
2018-01-08 07:56:10 +01:00
ric = data[21:28].replace(" ", "").zfill(7)
subric = str(int(data[40]) + 1)
return bitrate, ric, subric