wenet/rx_ssdv.py

118 wiersze
3.4 KiB
Python

#!/usr/bin/env python
#
# SSDV Packet Receiver & Parser
# Decodes SSDV packets passed via stdin.
#
# Mark Jessop <vk5qi@rfhead.net>
#
# Requires: ssdv (https://github.com/fsphil/ssdv)
#
import os,sys, datetime, argparse, socket
parser = argparse.ArgumentParser()
parser.add_argument("--hex", action="store_true", help="Take Hex strings as input instead of raw data.")
parser.add_argument("--partialupdate",default=0,help="Push partial updates every N packets to GUI.")
args = parser.parse_args()
# Helper functions to extract data from SSDV packets.
def ssdv_packet_info(packet):
packet = list(bytearray(packet))
# Check packet is actually a SSDV packet.
if len(packet) != 256:
return {'error': "ERROR: Invalid Packet Length"}
# We got this far, may as well try and extract the packet info.
try:
packet_info = {
'callsign' : "???", # TODO: Callsign decoding.
'packet_type' : "FEC" if (packet[1]==0x66) else "No-FEC",
'image_id' : packet[6],
'packet_id' : (packet[7]<<8) + packet[8],
'width' : packet[9]*16,
'height' : packet[10]*16,
'error' : "None"
}
return packet_info
except Exception as e:
return {'error': "ERROR: %s" % str(e)}
def ssdv_packet_string(packet_info):
return "SSDV: %s, Img:%d, Pkt:%d, %dx%d" % (packet_info['packet_type'],packet_info['image_id'],packet_info['packet_id'],packet_info['width'],packet_info['height'])
def trigger_gui_update(filename):
gui_socket = socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
gui_socket.sendto(filename,("127.0.0.1",7890))
gui_socket.close()
# State variables
current_image = -1
current_packet_count = 0
current_packet_time = datetime.datetime.utcnow().strftime("%Y%m%d-%H%M%SZ")
# Open temporary file for storing data.
temp_f = open("rxtemp.bin",'wb')
while True:
if args.hex:
data = sys.stdin.readline().rstrip().decode('hex')
else:
data = sys.stdin.read(256)
packet_info = ssdv_packet_info(data)
# Don't continue if we have a decode error.
if packet_info['error'] != "None":
continue
print(ssdv_packet_string(packet_info))
if packet_info['image_id'] != current_image:
# Attempt to decode current image if we have enough packets.
print("New image!")
if current_packet_count > 0:
# Attempt to decode current image, and write out to a file.
temp_f.close()
# Run SSDV
returncode = os.system("ssdv -d rxtemp.bin %s.jpg" % current_packet_time)
if returncode == 1:
print("ERROR: SSDV Decode failed!")
else:
print("SSDV Decoded OK!")
# Make a copy of the raw binary data.
os.system("mv rxtemp.bin %s.ssdv" % current_packet_time)
# Update live displays here.
trigger_gui_update("%s.jpg" % current_packet_time)
# Trigger upload to habhub here.
else:
print("Not enough packets to decode previous image.")
# Now set up for the new image.
current_image = packet_info['image_id']
current_packet_count = 1
current_packet_time = datetime.datetime.utcnow().strftime("%Y%m%d-%H%M%SZ")
# Open file and write in first packet.
temp_f = open("rxtemp.bin" , "wb")
temp_f.write(data)
else:
# Write current packet into temp file.
temp_f.write(data)
current_packet_count += 1
if args.partialupdate != 0:
if current_packet_count % int(args.partialupdate) == 0:
# Run the SSDV decoder and push a partial update to the GUI.
temp_f.flush()
returncode = os.system("ssdv -d rxtemp.bin rxtemp.jpg")
if returncode == 0:
trigger_gui_update("rxtemp.jpg")