ais.ais_msg

1 #!/usr/bin/env python 2 3 __version__ = '$Revision: 4791 $'.split()[1] 4 __date__ = '$Date: 2007-12-04 $'.split()[1] 5 __author__ = 'xmlbinmsg' 6 7 __doc__=''' 8 9 Autogenerated python functions to serialize/deserialize binary messages. 10 11 Generated by: ./aisxmlbinmsg2py.py 12 13 Need to then wrap these functions with the outer AIS packet and then 14 convert the whole binary blob to a NMEA string. Those functions are 15 not currently provided in this file. 16 17 serialize: python to ais binary 18 deserialize: ais binary to python 19 20 The generated code uses translators.py, binary.py, and aisstring.py 21 which should be packaged with the resulting files. 22 23 24 @requires: U{epydoc<http://epydoc.sourceforge.net/>} > 3.0alpha3 25 @requires: U{BitVector<http://cheeseshop.python.org/pypi/BitVector>} 26 27 @author: '''+__author__+''' 28 @version: ''' + __version__ +''' 29 @var __date__: Date of last svn commit 30 @undocumented: __version__ __author__ __doc__ parser 31 @status: under development 32 @license: Generated code has no license 33 @todo: FIX: put in a description of the message here with fields and types. 34 ''' 35 36 import sys 37 from decimal import Decimal 38 from BitVector import BitVector 39 40 import binary, aisstring 41 42 # FIX: check to see if these will be needed 43 TrueBV = BitVector(bitstring="1") 44 "Why always rebuild the True bit? This should speed things up a bunch" 45 FalseBV = BitVector(bitstring="0") 46 "Why always rebuild the False bit? This should speed things up a bunch" 47 48 49 fieldList = ( 50 'MessageID', 51 'RepeatIndicator', 52 'UserID', 53 'Reserved1', 54 'SOG', 55 'PositionAccuracy', 56 'longitude', 57 'latitude', 58 'COG', 59 'TrueHeading', 60 'TimeStamp', 61 'RegionalReserved', 62 'Spare', 63 'RAIM', 64 'CommStateSelector', 65 'CommState', 66 ) 67 68 fieldListPostgres = ( 69 'MessageID', 70 'RepeatIndicator', 71 'UserID', 72 'Reserved1', 73 'SOG', 74 'PositionAccuracy', 75 'Position', # PostGIS data type 76 'COG', 77 'TrueHeading', 78 'TimeStamp', 79 'RegionalReserved', 80 'Spare', 81 'RAIM', 82 'CommStateSelector', 83 'CommState', 84 ) 85 86 toPgFields = { 87 'longitude':'Position', 88 'latitude':'Position', 89 } 90 ''' 91 Go to the Postgis field names from the straight field name 92 ''' 93 94 fromPgFields = { 95 'Position':('longitude','latitude',), 96 } 97 ''' 98 Go from the Postgis field names to the straight field name 99 ''' 100 101 pgTypes = { 102 'Position':'POINT', 103 } 104 ''' 105 Lookup table for each postgis field name to get its type. 106 ''' 107

108 -def encode(params, validate=False):

109 '''Create a position binary message payload to pack into an AIS Msg position. 110 111 Fields in params: 112 - MessageID(uint): AIS message number. Must be 18 (field automatically set to "18") 113 - RepeatIndicator(uint): Indicated how many times a message has been repeated 114 - UserID(uint): Unique ship identification number (MMSI) 115 - Reserved1(uint): Reseverd for definition by a compentent regional or local authority. Should be set to zero. (field automatically set to "0") 116 - SOG(udecimal): Speed over ground 117 - PositionAccuracy(uint): Accuracy of positioning fixes 118 - longitude(decimal): Location of the vessel East West location 119 - latitude(decimal): Location of the vessel North South location 120 - COG(udecimal): Course over ground 121 - TrueHeading(uint): True heading (relative to true North) 122 - TimeStamp(uint): UTC second when the report was generated 123 - RegionalReserved(uint): Reserved for definition by a regional authority. (field automatically set to "0") 124 - Spare(uint): Not used. Should be set to zero. (field automatically set to "0") 125 - RAIM(bool): Receiver autonomous integrity monitoring flag 126 - CommStateSelector(uint): SOTDMA or ITDMA 127 - CommState(uint): Not decoded by this software yet 128 @param params: Dictionary of field names/values. Throws a ValueError exception if required is missing 129 @param validate: Set to true to cause checking to occur. Runs slower. FIX: not implemented. 130 @rtype: BitVector 131 @return: encoded binary message (for binary messages, this needs to be wrapped in a msg 8 132 @note: The returned bits may not be 6 bit aligned. It is up to you to pad out the bits. 133 ''' 134 135 bvList = [] 136 bvList.append(binary.setBitVectorSize(BitVector(intVal=18),6)) 137 if 'RepeatIndicator' in params: 138 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['RepeatIndicator']),2)) 139 else: 140 bvList.append(binary.setBitVectorSize(BitVector(intVal=0),2)) 141 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['UserID']),30)) 142 bvList.append(binary.setBitVectorSize(BitVector(intVal=0),8)) 143 if 'SOG' in params: 144 bvList.append(binary.setBitVectorSize(BitVector(intVal=int((Decimal(params['SOG'])*Decimal('10')))),10)) 145 else: 146 bvList.append(binary.setBitVectorSize(BitVector(intVal=int(1023)),10)) 147 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['PositionAccuracy']),1)) 148 if 'longitude' in params: 149 bvList.append(binary.bvFromSignedInt(int(Decimal(params['longitude'])*Decimal('600000')),28)) 150 else: 151 bvList.append(binary.bvFromSignedInt(108600000,28)) 152 if 'latitude' in params: 153 bvList.append(binary.bvFromSignedInt(int(Decimal(params['latitude'])*Decimal('600000')),27)) 154 else: 155 bvList.append(binary.bvFromSignedInt(54600000,27)) 156 if 'COG' in params: 157 bvList.append(binary.setBitVectorSize(BitVector(intVal=int((Decimal(params['COG'])*Decimal('10')))),12)) 158 else: 159 bvList.append(binary.setBitVectorSize(BitVector(intVal=int(3600)),12)) 160 if 'TrueHeading' in params: 161 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['TrueHeading']),9)) 162 else: 163 bvList.append(binary.setBitVectorSize(BitVector(intVal=511),9)) 164 if 'TimeStamp' in params: 165 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['TimeStamp']),6)) 166 else: 167 bvList.append(binary.setBitVectorSize(BitVector(intVal=60),6)) 168 bvList.append(binary.setBitVectorSize(BitVector(intVal=0),4)) 169 bvList.append(binary.setBitVectorSize(BitVector(intVal=0),4)) 170 if params["RAIM"]: bvList.append(TrueBV) 171 else: bvList.append(FalseBV) 172 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['CommStateSelector']),1)) 173 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['CommState']),19)) 174 175 return binary.joinBV(bvList)

176

177 -def decode(bv, validate=False):

178 '''Unpack a position message 179 180 Fields in params: 181 - MessageID(uint): AIS message number. Must be 18 (field automatically set to "18") 182 - RepeatIndicator(uint): Indicated how many times a message has been repeated 183 - UserID(uint): Unique ship identification number (MMSI) 184 - Reserved1(uint): Reseverd for definition by a compentent regional or local authority. Should be set to zero. (field automatically set to "0") 185 - SOG(udecimal): Speed over ground 186 - PositionAccuracy(uint): Accuracy of positioning fixes 187 - longitude(decimal): Location of the vessel East West location 188 - latitude(decimal): Location of the vessel North South location 189 - COG(udecimal): Course over ground 190 - TrueHeading(uint): True heading (relative to true North) 191 - TimeStamp(uint): UTC second when the report was generated 192 - RegionalReserved(uint): Reserved for definition by a regional authority. (field automatically set to "0") 193 - Spare(uint): Not used. Should be set to zero. (field automatically set to "0") 194 - RAIM(bool): Receiver autonomous integrity monitoring flag 195 - CommStateSelector(uint): SOTDMA or ITDMA 196 - CommState(uint): Not decoded by this software yet 197 @type bv: BitVector 198 @param bv: Bits defining a message 199 @param validate: Set to true to cause checking to occur. Runs slower. FIX: not implemented. 200 @rtype: dict 201 @return: params 202 ''' 203 204 #Would be nice to check the bit count here.. 205 #if validate: 206 # assert (len(bv)==FIX: SOME NUMBER) 207 r = {} 208 r['MessageID']=18 209 r['RepeatIndicator']=int(bv[6:8]) 210 r['UserID']=int(bv[8:38]) 211 r['Reserved1']=0 212 r['SOG']=Decimal(int(bv[46:56]))/Decimal('10') 213 r['PositionAccuracy']=int(bv[56:57]) 214 r['longitude']=Decimal(binary.signedIntFromBV(bv[57:85]))/Decimal('600000') 215 r['latitude']=Decimal(binary.signedIntFromBV(bv[85:112]))/Decimal('600000') 216 r['COG']=Decimal(int(bv[112:124]))/Decimal('10') 217 r['TrueHeading']=int(bv[124:133]) 218 r['TimeStamp']=int(bv[133:139]) 219 r['RegionalReserved']=0 220 r['Spare']=0 221 r['RAIM']=bool(int(bv[147:148])) 222 r['CommStateSelector']=int(bv[148:149]) 223 r['CommState']=int(bv[149:168]) 224 return r

225

226 -def decodeMessageID(bv, validate=False):

227 return 18

228

229 -def decodeRepeatIndicator(bv, validate=False):

230 return int(bv[6:8])

231

232 -def decodeUserID(bv, validate=False):

233 return int(bv[8:38])

234

235 -def decodeReserved1(bv, validate=False):

236 return 0

237

238 -def decodeSOG(bv, validate=False):

239 return Decimal(int(bv[46:56]))/Decimal('10')

240

241 -def decodePositionAccuracy(bv, validate=False):

242 return int(bv[56:57])

243

244 -def decodelongitude(bv, validate=False):

245 return Decimal(binary.signedIntFromBV(bv[57:85]))/Decimal('600000')

246

247 -def decodelatitude(bv, validate=False):

248 return Decimal(binary.signedIntFromBV(bv[85:112]))/Decimal('600000')

249

250 -def decodeCOG(bv, validate=False):

251 return Decimal(int(bv[112:124]))/Decimal('10')

252

253 -def decodeTrueHeading(bv, validate=False):

254 return int(bv[124:133])

255

256 -def decodeTimeStamp(bv, validate=False):

257 return int(bv[133:139])

258

259 -def decodeRegionalReserved(bv, validate=False):

260 return 0

261

262 -def decodeSpare(bv, validate=False):

263 return 0

264

265 -def decodeRAIM(bv, validate=False):

266 return bool(int(bv[147:148]))

267

268 -def decodeCommStateSelector(bv, validate=False):

269 return int(bv[148:149])

270

271 -def decodeCommState(bv, validate=False):

272 return int(bv[149:168])

273 274

275 -def printHtml(params, out=sys.stdout):

276 out.write("<h3>position</h3>\n") 277 out.write("<table border=\"1\">\n") 278 out.write("<tr bgcolor=\"orange\">\n") 279 out.write("<th align=\"left\">Field Name</th>\n") 280 out.write("<th align=\"left\">Type</th>\n") 281 out.write("<th align=\"left\">Value</th>\n") 282 out.write("<th align=\"left\">Value in Lookup Table</th>\n") 283 out.write("<th align=\"left\">Units</th>\n") 284 out.write("\n") 285 out.write("<tr>\n") 286 out.write("<td>MessageID</td>\n") 287 out.write("<td>uint</td>\n") 288 if 'MessageID' in params: 289 out.write(" <td>"+str(params['MessageID'])+"</td>\n") 290 out.write(" <td>"+str(params['MessageID'])+"</td>\n") 291 out.write("</tr>\n") 292 out.write("\n") 293 out.write("<tr>\n") 294 out.write("<td>RepeatIndicator</td>\n") 295 out.write("<td>uint</td>\n") 296 if 'RepeatIndicator' in params: 297 out.write(" <td>"+str(params['RepeatIndicator'])+"</td>\n") 298 if str(params['RepeatIndicator']) in RepeatIndicatorDecodeLut: 299 out.write("<td>"+RepeatIndicatorDecodeLut[str(params['RepeatIndicator'])]+"</td>") 300 else: 301 out.write("<td><i>Missing LUT entry</i></td>") 302 out.write("</tr>\n") 303 out.write("\n") 304 out.write("<tr>\n") 305 out.write("<td>UserID</td>\n") 306 out.write("<td>uint</td>\n") 307 if 'UserID' in params: 308 out.write(" <td>"+str(params['UserID'])+"</td>\n") 309 out.write(" <td>"+str(params['UserID'])+"</td>\n") 310 out.write("</tr>\n") 311 out.write("\n") 312 out.write("<tr>\n") 313 out.write("<td>Reserved1</td>\n") 314 out.write("<td>uint</td>\n") 315 if 'Reserved1' in params: 316 out.write(" <td>"+str(params['Reserved1'])+"</td>\n") 317 out.write(" <td>"+str(params['Reserved1'])+"</td>\n") 318 out.write("</tr>\n") 319 out.write("\n") 320 out.write("<tr>\n") 321 out.write("<td>SOG</td>\n") 322 out.write("<td>udecimal</td>\n") 323 if 'SOG' in params: 324 out.write(" <td>"+str(params['SOG'])+"</td>\n") 325 if str(params['SOG']) in SOGDecodeLut: 326 out.write("<td>"+SOGDecodeLut[str(params['SOG'])]+"</td>") 327 else: 328 out.write("<td><i>Missing LUT entry</i></td>") 329 out.write("<td>knots</td>\n") 330 out.write("</tr>\n") 331 out.write("\n") 332 out.write("<tr>\n") 333 out.write("<td>PositionAccuracy</td>\n") 334 out.write("<td>uint</td>\n") 335 if 'PositionAccuracy' in params: 336 out.write(" <td>"+str(params['PositionAccuracy'])+"</td>\n") 337 if str(params['PositionAccuracy']) in PositionAccuracyDecodeLut: 338 out.write("<td>"+PositionAccuracyDecodeLut[str(params['PositionAccuracy'])]+"</td>") 339 else: 340 out.write("<td><i>Missing LUT entry</i></td>") 341 out.write("</tr>\n") 342 out.write("\n") 343 out.write("<tr>\n") 344 out.write("<td>longitude</td>\n") 345 out.write("<td>decimal</td>\n") 346 if 'longitude' in params: 347 out.write(" <td>"+str(params['longitude'])+"</td>\n") 348 out.write(" <td>"+str(params['longitude'])+"</td>\n") 349 out.write("<td>degrees</td>\n") 350 out.write("</tr>\n") 351 out.write("\n") 352 out.write("<tr>\n") 353 out.write("<td>latitude</td>\n") 354 out.write("<td>decimal</td>\n") 355 if 'latitude' in params: 356 out.write(" <td>"+str(params['latitude'])+"</td>\n") 357 out.write(" <td>"+str(params['latitude'])+"</td>\n") 358 out.write("<td>degrees</td>\n") 359 out.write("</tr>\n") 360 out.write("\n") 361 out.write("<tr>\n") 362 out.write("<td>COG</td>\n") 363 out.write("<td>udecimal</td>\n") 364 if 'COG' in params: 365 out.write(" <td>"+str(params['COG'])+"</td>\n") 366 out.write(" <td>"+str(params['COG'])+"</td>\n") 367 out.write("<td>degrees</td>\n") 368 out.write("</tr>\n") 369 out.write("\n") 370 out.write("<tr>\n") 371 out.write("<td>TrueHeading</td>\n") 372 out.write("<td>uint</td>\n") 373 if 'TrueHeading' in params: 374 out.write(" <td>"+str(params['TrueHeading'])+"</td>\n") 375 out.write(" <td>"+str(params['TrueHeading'])+"</td>\n") 376 out.write("<td>degrees</td>\n") 377 out.write("</tr>\n") 378 out.write("\n") 379 out.write("<tr>\n") 380 out.write("<td>TimeStamp</td>\n") 381 out.write("<td>uint</td>\n") 382 if 'TimeStamp' in params: 383 out.write(" <td>"+str(params['TimeStamp'])+"</td>\n") 384 if str(params['TimeStamp']) in TimeStampDecodeLut: 385 out.write("<td>"+TimeStampDecodeLut[str(params['TimeStamp'])]+"</td>") 386 else: 387 out.write("<td><i>Missing LUT entry</i></td>") 388 out.write("<td>seconds</td>\n") 389 out.write("</tr>\n") 390 out.write("\n") 391 out.write("<tr>\n") 392 out.write("<td>RegionalReserved</td>\n") 393 out.write("<td>uint</td>\n") 394 if 'RegionalReserved' in params: 395 out.write(" <td>"+str(params['RegionalReserved'])+"</td>\n") 396 out.write(" <td>"+str(params['RegionalReserved'])+"</td>\n") 397 out.write("</tr>\n") 398 out.write("\n") 399 out.write("<tr>\n") 400 out.write("<td>Spare</td>\n") 401 out.write("<td>uint</td>\n") 402 if 'Spare' in params: 403 out.write(" <td>"+str(params['Spare'])+"</td>\n") 404 out.write(" <td>"+str(params['Spare'])+"</td>\n") 405 out.write("</tr>\n") 406 out.write("\n") 407 out.write("<tr>\n") 408 out.write("<td>RAIM</td>\n") 409 out.write("<td>bool</td>\n") 410 if 'RAIM' in params: 411 out.write(" <td>"+str(params['RAIM'])+"</td>\n") 412 if str(params['RAIM']) in RAIMDecodeLut: 413 out.write("<td>"+RAIMDecodeLut[str(params['RAIM'])]+"</td>") 414 else: 415 out.write("<td><i>Missing LUT entry</i></td>") 416 out.write("</tr>\n") 417 out.write("\n") 418 out.write("<tr>\n") 419 out.write("<td>CommStateSelector</td>\n") 420 out.write("<td>uint</td>\n") 421 if 'CommStateSelector' in params: 422 out.write(" <td>"+str(params['CommStateSelector'])+"</td>\n") 423 if str(params['CommStateSelector']) in CommStateSelectorDecodeLut: 424 out.write("<td>"+CommStateSelectorDecodeLut[str(params['CommStateSelector'])]+"</td>") 425 else: 426 out.write("<td><i>Missing LUT entry</i></td>") 427 out.write("</tr>\n") 428 out.write("\n") 429 out.write("<tr>\n") 430 out.write("<td>CommState</td>\n") 431 out.write("<td>uint</td>\n") 432 if 'CommState' in params: 433 out.write(" <td>"+str(params['CommState'])+"</td>\n") 434 out.write(" <td>"+str(params['CommState'])+"</td>\n") 435 out.write("</tr>\n") 436 out.write("</table>\n")

437 438

439 -def printKml(params, out=sys.stdout):

440 '''KML (Keyhole Markup Language) for Google Earth, but without the header/footer''' 441 out.write("\ <Placemark>\n") 442 out.write("\t <name>"+str(params['UserID'])+"</name>\n") 443 out.write("\t\t<description>\n") 444 import StringIO 445 buf = StringIO.StringIO() 446 printHtml(params,buf) 447 import cgi 448 out.write(cgi.escape(buf.getvalue())) 449 out.write("\t\t</description>\n") 450 out.write("\t\t<styleUrl>#m_ylw-pushpin_copy0</styleUrl>\n") 451 out.write("\t\t<Point>\n") 452 out.write("\t\t\t<coordinates>") 453 out.write(str(params['longitude'])) 454 out.write(',') 455 out.write(str(params['latitude'])) 456 out.write(",0</coordinates>\n") 457 out.write("\t\t</Point>\n") 458 out.write("\t</Placemark>\n")

459

460 -def printFields(params, out=sys.stdout, format='std', fieldList=None, dbType='postgres'):

461 '''Print a position message to stdout. 462 463 Fields in params: 464 - MessageID(uint): AIS message number. Must be 18 (field automatically set to "18") 465 - RepeatIndicator(uint): Indicated how many times a message has been repeated 466 - UserID(uint): Unique ship identification number (MMSI) 467 - Reserved1(uint): Reseverd for definition by a compentent regional or local authority. Should be set to zero. (field automatically set to "0") 468 - SOG(udecimal): Speed over ground 469 - PositionAccuracy(uint): Accuracy of positioning fixes 470 - longitude(decimal): Location of the vessel East West location 471 - latitude(decimal): Location of the vessel North South location 472 - COG(udecimal): Course over ground 473 - TrueHeading(uint): True heading (relative to true North) 474 - TimeStamp(uint): UTC second when the report was generated 475 - RegionalReserved(uint): Reserved for definition by a regional authority. (field automatically set to "0") 476 - Spare(uint): Not used. Should be set to zero. (field automatically set to "0") 477 - RAIM(bool): Receiver autonomous integrity monitoring flag 478 - CommStateSelector(uint): SOTDMA or ITDMA 479 - CommState(uint): Not decoded by this software yet 480 @param params: Dictionary of field names/values. 481 @param out: File like object to write to 482 @rtype: stdout 483 @return: text to out 484 ''' 485 486 if 'std'==format: 487 out.write("position:\n") 488 if 'MessageID' in params: out.write(" MessageID: "+str(params['MessageID'])+"\n") 489 if 'RepeatIndicator' in params: out.write(" RepeatIndicator: "+str(params['RepeatIndicator'])+"\n") 490 if 'UserID' in params: out.write(" UserID: "+str(params['UserID'])+"\n") 491 if 'Reserved1' in params: out.write(" Reserved1: "+str(params['Reserved1'])+"\n") 492 if 'SOG' in params: out.write(" SOG: "+str(params['SOG'])+"\n") 493 if 'PositionAccuracy' in params: out.write(" PositionAccuracy: "+str(params['PositionAccuracy'])+"\n") 494 if 'longitude' in params: out.write(" longitude: "+str(params['longitude'])+"\n") 495 if 'latitude' in params: out.write(" latitude: "+str(params['latitude'])+"\n") 496 if 'COG' in params: out.write(" COG: "+str(params['COG'])+"\n") 497 if 'TrueHeading' in params: out.write(" TrueHeading: "+str(params['TrueHeading'])+"\n") 498 if 'TimeStamp' in params: out.write(" TimeStamp: "+str(params['TimeStamp'])+"\n") 499 if 'RegionalReserved' in params: out.write(" RegionalReserved: "+str(params['RegionalReserved'])+"\n") 500 if 'Spare' in params: out.write(" Spare: "+str(params['Spare'])+"\n") 501 if 'RAIM' in params: out.write(" RAIM: "+str(params['RAIM'])+"\n") 502 if 'CommStateSelector' in params: out.write(" CommStateSelector: "+str(params['CommStateSelector'])+"\n") 503 if 'CommState' in params: out.write(" CommState: "+str(params['CommState'])+"\n") 504 elif 'csv'==format: 505 if None == options.fieldList: 506 options.fieldList = fieldList 507 needComma = False; 508 for field in fieldList: 509 if needComma: out.write(',') 510 needComma = True 511 if field in params: 512 out.write(str(params[field])) 513 # else: leave it empty 514 out.write("\n") 515 elif 'html'==format: 516 printHtml(params,out) 517 elif 'sql'==format: 518 sqlInsertStr(params,out,dbType=dbType) 519 elif 'kml'==format: 520 printKml(params,out) 521 elif 'kml-full'==format: 522 out.write("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n") 523 out.write("<kml xmlns=\"http://earth.google.com/kml/2.1\">\n") 524 out.write("<Document>\n") 525 out.write(" <name>position</name>\n") 526 printKml(params,out) 527 out.write("</Document>\n") 528 out.write("</kml>\n") 529 else: 530 print "ERROR: unknown format:",format 531 assert False 532 533 return # Nothing to return

534 535 RepeatIndicatorEncodeLut = { 536 'default':'0', 537 'do not repeat any more':'3', 538 } #RepeatIndicatorEncodeLut 539 540 RepeatIndicatorDecodeLut = { 541 '0':'default', 542 '3':'do not repeat any more', 543 } # RepeatIndicatorEncodeLut 544 545 SOGEncodeLut = { 546 '102.2 knots or higher':'102.2', 547 } #SOGEncodeLut 548 549 SOGDecodeLut = { 550 '102.2':'102.2 knots or higher', 551 } # SOGEncodeLut 552 553 PositionAccuracyEncodeLut = { 554 'low (greater than 10 m)':'0', 555 'high (less than 10 m)':'1', 556 } #PositionAccuracyEncodeLut 557 558 PositionAccuracyDecodeLut = { 559 '0':'low (greater than 10 m)', 560 '1':'high (less than 10 m)', 561 } # PositionAccuracyEncodeLut 562 563 TimeStampEncodeLut = { 564 'not available/default':'60', 565 'manual input':'61', 566 'dead reckoning':'62', 567 'inoperative':'63', 568 } #TimeStampEncodeLut 569 570 TimeStampDecodeLut = { 571 '60':'not available/default', 572 '61':'manual input', 573 '62':'dead reckoning', 574 '63':'inoperative', 575 } # TimeStampEncodeLut 576 577 RAIMEncodeLut = { 578 'not in use':'False', 579 'in use':'True', 580 } #RAIMEncodeLut 581 582 RAIMDecodeLut = { 583 'False':'not in use', 584 'True':'in use', 585 } # RAIMEncodeLut 586 587 CommStateSelectorEncodeLut = { 588 'SOTDMA':'0', 589 'ITDMA':'1', 590 } #CommStateSelectorEncodeLut 591 592 CommStateSelectorDecodeLut = { 593 '0':'SOTDMA', 594 '1':'ITDMA', 595 } # CommStateSelectorEncodeLut 596 597 ###################################################################### 598 # SQL SUPPORT 599 ###################################################################### 600

601 -def sqlCreateStr(outfile=sys.stdout, fields=None, extraFields=None 602 ,addCoastGuardFields=True 603 ,dbType='postgres' 604 ):

605 ''' 606 Return the SQL CREATE command for this message type 607 @param outfile: file like object to print to. 608 @param fields: which fields to put in the create. Defaults to all. 609 @param extraFields: A sequence of tuples containing (name,sql type) for additional fields 610 @param addCoastGuardFields: Add the extra fields that come after the NMEA check some from the USCG N-AIS format 611 @param dbType: Which flavor of database we are using so that the create is tailored ('sqlite' or 'postgres') 612 @type addCoastGuardFields: bool 613 @return: sql create string 614 @rtype: str 615 616 @see: sqlCreate 617 ''' 618 # FIX: should this sqlCreate be the same as in LaTeX (createFuncName) rather than hard coded? 619 outfile.write(str(sqlCreate(fields,extraFields,addCoastGuardFields,dbType=dbType)))

620

621 -def sqlCreate(fields=None, extraFields=None, addCoastGuardFields=True, dbType='postgres'):

622 ''' 623 Return the sqlhelp object to create the table. 624 625 @param fields: which fields to put in the create. Defaults to all. 626 @param extraFields: A sequence of tuples containing (name,sql type) for additional fields 627 @param addCoastGuardFields: Add the extra fields that come after the NMEA check some from the USCG N-AIS format 628 @type addCoastGuardFields: bool 629 @param dbType: Which flavor of database we are using so that the create is tailored ('sqlite' or 'postgres') 630 @return: An object that can be used to generate a return 631 @rtype: sqlhelp.create 632 ''' 633 if None == fields: fields = fieldList 634 import sqlhelp 635 c = sqlhelp.create('position',dbType=dbType) 636 c.addPrimaryKey() 637 if 'MessageID' in fields: c.addInt ('MessageID') 638 if 'RepeatIndicator' in fields: c.addInt ('RepeatIndicator') 639 if 'UserID' in fields: c.addInt ('UserID') 640 if 'Reserved1' in fields: c.addInt ('Reserved1') 641 if 'SOG' in fields: c.addDecimal('SOG',4,1) 642 if 'PositionAccuracy' in fields: c.addInt ('PositionAccuracy') 643 if dbType != 'postgres': 644 if 'longitude' in fields: c.addDecimal('longitude',8,5) 645 if dbType != 'postgres': 646 if 'latitude' in fields: c.addDecimal('latitude',8,5) 647 if 'COG' in fields: c.addDecimal('COG',4,1) 648 if 'TrueHeading' in fields: c.addInt ('TrueHeading') 649 if 'TimeStamp' in fields: c.addInt ('TimeStamp') 650 if 'RegionalReserved' in fields: c.addInt ('RegionalReserved') 651 if 'Spare' in fields: c.addInt ('Spare') 652 if 'RAIM' in fields: c.addBool('RAIM') 653 if 'CommStateSelector' in fields: c.addInt ('CommStateSelector') 654 if 'CommState' in fields: c.addInt ('CommState') 655 656 if addCoastGuardFields: 657 # c.addInt('cg_rssi') # Relative signal strength indicator 658 # c.addInt('cg_d') # dBm receive strength 659 # c.addInt('cg_T') # Receive timestamp from the AIS equipment 660 # c.addInt('cg_S') # Slot received in 661 # c.addVarChar('cg_x',10) # Idonno 662 c.addVarChar('cg_r',15) # Receiver station ID - should usually be an MMSI, but sometimes is a string 663 c.addInt('cg_sec') # UTC seconds since the epoch 664 665 c.addTimestamp('cg_timestamp') # UTC decoded cg_sec - not actually in the data stream 666 667 if dbType == 'postgres': 668 #--- EPSG 4326 : WGS 84 669 #INSERT INTO "spatial_ref_sys" ("srid","auth_name","auth_srid","srtext","proj4text") VALUES (4326,'EPSG',4326,'GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],TOWGS84[0,0,0,0,0,0,0],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4326"]]','+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs '); 670 c.addPostGIS('Position','POINT',2,SRID=4326); 671 672 return c

673

674 -def sqlInsertStr(params, outfile=sys.stdout, extraParams=None, dbType='postgres'):

675 ''' 676 Return the SQL INSERT command for this message type 677 @param params: dictionary of values keyed by field name 678 @param outfile: file like object to print to. 679 @param extraParams: A sequence of tuples containing (name,sql type) for additional fields 680 @return: sql create string 681 @rtype: str 682 683 @see: sqlCreate 684 ''' 685 outfile.write(str(sqlInsert(params,extraParams,dbType=dbType)))

686 687

688 -def sqlInsert(params,extraParams=None,dbType='postgres'):

689 ''' 690 Give the SQL INSERT statement 691 @param params: dict keyed by field name of values 692 @param extraParams: any extra fields that you have created beyond the normal ais message fields 693 @rtype: sqlhelp.insert 694 @return: insert class instance 695 @todo: allow optional type checking of params? 696 @warning: this will take invalid keys happily and do what??? 697 ''' 698 import sqlhelp 699 i = sqlhelp.insert('position',dbType=dbType) 700 701 if dbType=='postgres': 702 finished = [] 703 for key in params: 704 if key in finished: 705 continue 706 707 if key not in toPgFields and key not in fromPgFields: 708 if type(params[key])==Decimal: i.add(key,float(params[key])) 709 else: i.add(key,params[key]) 710 else: 711 if key in fromPgFields: 712 val = params[key] 713 # Had better be a WKT type like POINT(-88.1 30.321) 714 i.addPostGIS(key,val) 715 finished.append(key) 716 else: 717 # Need to construct the type. 718 pgName = toPgFields[key] 719 #valStr='GeomFromText(\''+pgTypes[pgName]+'(' 720 valStr=pgTypes[pgName]+'(' 721 vals = [] 722 for nonPgKey in fromPgFields[pgName]: 723 vals.append(str(params[nonPgKey])) 724 finished.append(nonPgKey) 725 valStr+=' '.join(vals)+')' 726 i.addPostGIS(pgName,valStr) 727 else: 728 for key in params: 729 if type(params[key])==Decimal: i.add(key,float(params[key])) 730 else: i.add(key,params[key]) 731 732 if None != extraParams: 733 for key in extraParams: 734 i.add(key,extraParams[key]) 735 736 return i

737 738 ###################################################################### 739 # LATEX SUPPORT 740 ###################################################################### 741

742 -def latexDefinitionTable(outfile=sys.stdout 743 ):

744 ''' 745 Return the LaTeX definition table for this message type 746 @param outfile: file like object to print to. 747 @type outfile: file obj 748 @return: LaTeX table string via the outfile 749 @rtype: str 750 751 ''' 752 o = outfile 753 754 o.write(''' 755 \\begin{table}%[htb] 756 \\centering 757 \\begin{tabular}{|l|c|l|} 758 \\hline 759 Parameter & Number of bits & Description 760 \\\\ \\hline\\hline 761 MessageID & 6 & AIS message number. Must be 18 \\\\ \hline 762 RepeatIndicator & 2 & Indicated how many times a message has been repeated \\\\ \hline 763 UserID & 30 & Unique ship identification number (MMSI) \\\\ \hline 764 Reserved1 & 8 & Reseverd for definition by a compentent regional or local authority. Should be set to zero. \\\\ \hline 765 SOG & 10 & Speed over ground \\\\ \hline 766 PositionAccuracy & 1 & Accuracy of positioning fixes \\\\ \hline 767 longitude & 28 & Location of the vessel East West location \\\\ \hline 768 latitude & 27 & Location of the vessel North South location \\\\ \hline 769 COG & 12 & Course over ground \\\\ \hline 770 TrueHeading & 9 & True heading (relative to true North) \\\\ \hline 771 TimeStamp & 6 & UTC second when the report was generated \\\\ \hline 772 RegionalReserved & 4 & Reserved for definition by a regional authority. \\\\ \hline 773 Spare & 4 & Not used. Should be set to zero. \\\\ \hline 774 RAIM & 1 & Receiver autonomous integrity monitoring flag \\\\ \hline 775 CommStateSelector & 1 & SOTDMA or ITDMA \\\\ \hline 776 CommState & 19 & Not decoded by this software yet\\\\ \\hline \\hline 777 Total bits & 168 & Appears to take 1 slot \\\\ \\hline 778 \\end{tabular} 779 \\caption{AIS message number 18: Standard Class B equipment position report} 780 \\label{tab:position} 781 \\end{table} 782 ''')

783 784 ###################################################################### 785 # Text Definition 786 ###################################################################### 787

788 -def textDefinitionTable(outfile=sys.stdout 789 ,delim='\t' 790 ):

791 ''' 792 Return the text definition table for this message type 793 @param outfile: file like object to print to. 794 @type outfile: file obj 795 @return: text table string via the outfile 796 @rtype: str 797 798 ''' 799 o = outfile 800 o.write('''Parameter'''+delim+'Number of bits'''+delim+'''Description 801 MessageID'''+delim+'''6'''+delim+'''AIS message number. Must be 18 802 RepeatIndicator'''+delim+'''2'''+delim+'''Indicated how many times a message has been repeated 803 UserID'''+delim+'''30'''+delim+'''Unique ship identification number (MMSI) 804 Reserved1'''+delim+'''8'''+delim+'''Reseverd for definition by a compentent regional or local authority. Should be set to zero. 805 SOG'''+delim+'''10'''+delim+'''Speed over ground 806 PositionAccuracy'''+delim+'''1'''+delim+'''Accuracy of positioning fixes 807 longitude'''+delim+'''28'''+delim+'''Location of the vessel East West location 808 latitude'''+delim+'''27'''+delim+'''Location of the vessel North South location 809 COG'''+delim+'''12'''+delim+'''Course over ground 810 TrueHeading'''+delim+'''9'''+delim+'''True heading (relative to true North) 811 TimeStamp'''+delim+'''6'''+delim+'''UTC second when the report was generated 812 RegionalReserved'''+delim+'''4'''+delim+'''Reserved for definition by a regional authority. 813 Spare'''+delim+'''4'''+delim+'''Not used. Should be set to zero. 814 RAIM'''+delim+'''1'''+delim+'''Receiver autonomous integrity monitoring flag 815 CommStateSelector'''+delim+'''1'''+delim+'''SOTDMA or ITDMA 816 CommState'''+delim+'''19'''+delim+'''Not decoded by this software yet 817 Total bits'''+delim+'''168'''+delim+'''Appears to take 1 slot''')

818 819 820 ###################################################################### 821 # UNIT TESTING 822 ###################################################################### 823 import unittest

824 -def testParams():

825 '''Return a params file base on the testvalue tags. 826 @rtype: dict 827 @return: params based on testvalue tags 828 ''' 829 params = {} 830 params['MessageID'] = 18 831 params['RepeatIndicator'] = 1 832 params['UserID'] = 1193046 833 params['Reserved1'] = 0 834 params['SOG'] = Decimal('101.9') 835 params['PositionAccuracy'] = 1 836 params['longitude'] = Decimal('-122.16328055555556') 837 params['latitude'] = Decimal('37.424458333333334') 838 params['COG'] = Decimal('34.5') 839 params['TrueHeading'] = 41 840 params['TimeStamp'] = 35 841 params['RegionalReserved'] = 0 842 params['Spare'] = 0 843 params['RAIM'] = False 844 params['CommStateSelector'] = 0 845 params['CommState'] = 0 846 847 return params

848

849 -class Testposition(unittest.TestCase):

850 '''Use testvalue tag text from each type to build test case the position message'''

851 - def testEncodeDecode(self):

852 853 params = testParams() 854 bits = encode(params) 855 r = decode(bits) 856 857 # Check that each parameter came through ok. 858 self.failUnlessEqual(r['MessageID'],params['MessageID']) 859 self.failUnlessEqual(r['RepeatIndicator'],params['RepeatIndicator']) 860 self.failUnlessEqual(r['UserID'],params['UserID']) 861 self.failUnlessEqual(r['Reserved1'],params['Reserved1']) 862 self.failUnlessAlmostEqual(r['SOG'],params['SOG'],1) 863 self.failUnlessEqual(r['PositionAccuracy'],params['PositionAccuracy']) 864 self.failUnlessAlmostEqual(r['longitude'],params['longitude'],5) 865 self.failUnlessAlmostEqual(r['latitude'],params['latitude'],5) 866 self.failUnlessAlmostEqual(r['COG'],params['COG'],1) 867 self.failUnlessEqual(r['TrueHeading'],params['TrueHeading']) 868 self.failUnlessEqual(r['TimeStamp'],params['TimeStamp']) 869 self.failUnlessEqual(r['RegionalReserved'],params['RegionalReserved']) 870 self.failUnlessEqual(r['Spare'],params['Spare']) 871 self.failUnlessEqual(r['RAIM'],params['RAIM']) 872 self.failUnlessEqual(r['CommStateSelector'],params['CommStateSelector']) 873 self.failUnlessEqual(r['CommState'],params['CommState'])

874

875 -def addMsgOptions(parser):

876 parser.add_option('-d','--decode',dest='doDecode',default=False,action='store_true', 877 help='decode a "position" AIS message') 878 parser.add_option('-e','--encode',dest='doEncode',default=False,action='store_true', 879 help='encode a "position" AIS message') 880 parser.add_option('--RepeatIndicator-field', dest='RepeatIndicatorField',default=0,metavar='uint',type='int' 881 ,help='Field parameter value [default: %default]') 882 parser.add_option('--UserID-field', dest='UserIDField',metavar='uint',type='int' 883 ,help='Field parameter value [default: %default]') 884 parser.add_option('--SOG-field', dest='SOGField',default=Decimal('102.3'),metavar='udecimal',type='string' 885 ,help='Field parameter value [default: %default]') 886 parser.add_option('--PositionAccuracy-field', dest='PositionAccuracyField',metavar='uint',type='int' 887 ,help='Field parameter value [default: %default]') 888 parser.add_option('--longitude-field', dest='longitudeField',default=Decimal('181'),metavar='decimal',type='string' 889 ,help='Field parameter value [default: %default]') 890 parser.add_option('--latitude-field', dest='latitudeField',default=Decimal('91'),metavar='decimal',type='string' 891 ,help='Field parameter value [default: %default]') 892 parser.add_option('--COG-field', dest='COGField',default=Decimal('360'),metavar='udecimal',type='string' 893 ,help='Field parameter value [default: %default]') 894 parser.add_option('--TrueHeading-field', dest='TrueHeadingField',default=511,metavar='uint',type='int' 895 ,help='Field parameter value [default: %default]') 896 parser.add_option('--TimeStamp-field', dest='TimeStampField',default=60,metavar='uint',type='int' 897 ,help='Field parameter value [default: %default]') 898 parser.add_option('--RAIM-field', dest='RAIMField',metavar='bool',type='int' 899 ,help='Field parameter value [default: %default]') 900 parser.add_option('--CommStateSelector-field', dest='CommStateSelectorField',metavar='uint',type='int' 901 ,help='Field parameter value [default: %default]') 902 parser.add_option('--CommState-field', dest='CommStateField',metavar='uint',type='int' 903 ,help='Field parameter value [default: %default]')

904 905 ############################################################ 906 if __name__=='__main__': 907 908 from optparse import OptionParser 909 parser = OptionParser(usage="%prog [options]", 910 version="%prog "+__version__) 911 912 parser.add_option('--doc-test',dest='doctest',default=False,action='store_true', 913 help='run the documentation tests') 914 parser.add_option('--unit-test',dest='unittest',default=False,action='store_true', 915 help='run the unit tests') 916 parser.add_option('-v','--verbose',dest='verbose',default=False,action='store_true', 917 help='Make the test output verbose') 918 919 # FIX: remove nmea from binary messages. No way to build the whole packet? 920 # FIX: or build the surrounding msg 8 for a broadcast? 921 typeChoices = ('binary','nmeapayload','nmea') # FIX: what about a USCG type message? 922 parser.add_option('-t','--type',choices=typeChoices,type='choice',dest='ioType' 923 ,default='nmeapayload' 924 ,help='What kind of string to write for encoding ('+', '.join(typeChoices)+') [default: %default]') 925 926 927 outputChoices = ('std','html','csv','sql' , 'kml','kml-full') 928 parser.add_option('-T','--output-type',choices=outputChoices,type='choice',dest='outputType' 929 ,default='std' 930 ,help='What kind of string to output ('+', '.join(outputChoices)+') [default: %default]') 931 932 parser.add_option('-o','--output',dest='outputFileName',default=None, 933 help='Name of the python file to write [default: stdout]') 934 935 parser.add_option('-f','--fields',dest='fieldList',default=None, action='append', 936 choices=fieldList, 937 help='Which fields to include in the output. Currently only for csv output [default: all]') 938 939 parser.add_option('-p','--print-csv-field-list',dest='printCsvfieldList',default=False,action='store_true', 940 help='Print the field name for csv') 941 942 parser.add_option('-c','--sql-create',dest='sqlCreate',default=False,action='store_true', 943 help='Print out an sql create command for the table.') 944 945 parser.add_option('--latex-table',dest='latexDefinitionTable',default=False,action='store_true', 946 help='Print a LaTeX table of the type') 947 948 parser.add_option('--text-table',dest='textDefinitionTable',default=False,action='store_true', 949 help='Print delimited table of the type (for Word table importing)') 950 parser.add_option('--delimt-text-table',dest='delimTextDefinitionTable',default='\t' 951 ,help='Delimiter for text table [default: \'%default\'](for Word table importing)') 952 953 954 dbChoices = ('sqlite','postgres') 955 parser.add_option('-D','--db-type',dest='dbType',default='postgres' 956 ,choices=dbChoices,type='choice' 957 ,help='What kind of database ('+', '.join(dbChoices)+') [default: %default]') 958 959 addMsgOptions(parser) 960 961 (options,args) = parser.parse_args() 962 success=True 963 964 if options.doctest: 965 import os; print os.path.basename(sys.argv[0]), 'doctests ...', 966 sys.argv= [sys.argv[0]] 967 if options.verbose: sys.argv.append('-v') 968 import doctest 969 numfail,numtests=doctest.testmod() 970 if numfail==0: print 'ok' 971 else: 972 print 'FAILED' 973 success=False 974 975 if not success: sys.exit('Something Failed') 976 del success # Hide success from epydoc 977 978 if options.unittest: 979 sys.argv = [sys.argv[0]] 980 if options.verbose: sys.argv.append('-v') 981 unittest.main() 982 983 outfile = sys.stdout 984 if None!=options.outputFileName: 985 outfile = file(options.outputFileName,'w') 986 987 988 if options.doEncode: 989 # First make sure all non required options are specified 990 if None==options.RepeatIndicatorField: parser.error("missing value for RepeatIndicatorField") 991 if None==options.UserIDField: parser.error("missing value for UserIDField") 992 if None==options.SOGField: parser.error("missing value for SOGField") 993 if None==options.PositionAccuracyField: parser.error("missing value for PositionAccuracyField") 994 if None==options.longitudeField: parser.error("missing value for longitudeField") 995 if None==options.latitudeField: parser.error("missing value for latitudeField") 996 if None==options.COGField: parser.error("missing value for COGField") 997 if None==options.TrueHeadingField: parser.error("missing value for TrueHeadingField") 998 if None==options.TimeStampField: parser.error("missing value for TimeStampField") 999 if None==options.RAIMField: parser.error("missing value for RAIMField") 1000 if None==options.CommStateSelectorField: parser.error("missing value for CommStateSelectorField") 1001 if None==options.CommStateField: parser.error("missing value for CommStateField") 1002 msgDict={ 1003 'MessageID': '18', 1004 'RepeatIndicator': options.RepeatIndicatorField, 1005 'UserID': options.UserIDField, 1006 'Reserved1': '0', 1007 'SOG': options.SOGField, 1008 'PositionAccuracy': options.PositionAccuracyField, 1009 'longitude': options.longitudeField, 1010 'latitude': options.latitudeField, 1011 'COG': options.COGField, 1012 'TrueHeading': options.TrueHeadingField, 1013 'TimeStamp': options.TimeStampField, 1014 'RegionalReserved': '0', 1015 'Spare': '0', 1016 'RAIM': options.RAIMField, 1017 'CommStateSelector': options.CommStateSelectorField, 1018 'CommState': options.CommStateField, 1019 } 1020 1021 bits = encode(msgDict) 1022 if 'binary'==options.ioType: print str(bits) 1023 elif 'nmeapayload'==options.ioType: 1024 # FIX: figure out if this might be necessary at compile time 1025 print "bitLen",len(bits) 1026 bitLen=len(bits) 1027 if bitLen%6!=0: 1028 bits = bits + BitVector(size=(6 - (bitLen%6))) # Pad out to multiple of 6 1029 print "result:",binary.bitvectoais6(bits)[0] 1030 1031 1032 # FIX: Do not emit this option for the binary message payloads. Does not make sense. 1033 elif 'nmea'==options.ioType: sys.exit("FIX: need to implement this capability") 1034 else: sys.exit('ERROR: unknown ioType. Help!') 1035 1036 1037 if options.sqlCreate: 1038 sqlCreateStr(outfile,options.fieldList,dbType=options.dbType) 1039 1040 if options.latexDefinitionTable: 1041 latexDefinitionTable(outfile) 1042 1043 # For conversion to word tables 1044 if options.textDefinitionTable: 1045 textDefinitionTable(outfile,options.delimTextDefinitionTable) 1046 1047 if options.printCsvfieldList: 1048 # Make a csv separated list of fields that will be displayed for csv 1049 if None == options.fieldList: options.fieldList = fieldList 1050 import StringIO 1051 buf = StringIO.StringIO() 1052 for field in options.fieldList: 1053 buf.write(field+',') 1054 result = buf.getvalue() 1055 if result[-1] == ',': print result[:-1] 1056 else: print result 1057 1058 if options.doDecode: 1059 if len(args)==0: args = sys.stdin 1060 for msg in args: 1061 bv = None 1062 1063 if msg[0] in ('$','!') and msg[3:6] in ('VDM','VDO'): 1064 # Found nmea 1065 # FIX: do checksum 1066 bv = binary.ais6tobitvec(msg.split(',')[5]) 1067 else: # either binary or nmeapayload... expect mostly nmeapayloads 1068 # assumes that an all 0 and 1 string can not be a nmeapayload 1069 binaryMsg=True 1070 for c in msg: 1071 if c not in ('0','1'): 1072 binaryMsg=False 1073 break 1074 if binaryMsg: 1075 bv = BitVector(bitstring=msg) 1076 else: # nmeapayload 1077 bv = binary.ais6tobitvec(msg) 1078 1079 printFields(decode(bv) 1080 ,out=outfile 1081 ,format=options.outputType 1082 ,fieldList=options.fieldList 1083 ,dbType=options.dbType 1084 ) 1085

Source Code for Module ais.ais_msg_18