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			973 lines
		
	
	
		
			29 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			973 lines
		
	
	
		
			29 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| ///////////////////////////////////////////////////////////////////////////////////
 | |
| // Copyright (C) 2023 Jon Beniston, M7RCE <jon@beniston.com>                     //
 | |
| //                                                                               //
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| // This program is free software; you can redistribute it and/or modify          //
 | |
| // it under the terms of the GNU General Public License as published by          //
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| // the Free Software Foundation as version 3 of the License, or                  //
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| // (at your option) any later version.                                           //
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| //                                                                               //
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| // This program is distributed in the hope that it will be useful,               //
 | |
| // but WITHOUT ANY WARRANTY; without even the implied warranty of                //
 | |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the                  //
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| // GNU General Public License V3 for more details.                               //
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| //                                                                               //
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| // You should have received a copy of the GNU General Public License             //
 | |
| // along with this program. If not, see <http://www.gnu.org/licenses/>.          //
 | |
| ///////////////////////////////////////////////////////////////////////////////////
 | |
| 
 | |
| #include <QDebug>
 | |
| 
 | |
| #include "util/dsc.h"
 | |
| #include "util/popcount.h"
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| 
 | |
| // "short" strings are meant to be compatible with YaDDNet
 | |
| 
 | |
| QMap<DSCMessage::FormatSpecifier, QString> DSCMessage::m_formatSpecifierStrings = {
 | |
|     {GEOGRAPHIC_CALL, "Geographic call"},
 | |
|     {DISTRESS_ALERT,  "Distress alert"},
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|     {GROUP_CALL,      "Group call"},
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|     {ALL_SHIPS,       "All ships"},
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|     {SELECTIVE_CALL,  "Selective call"},
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|     {AUTOMATIC_CALL,  "Automatic call"}
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| };
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| 
 | |
| QMap<DSCMessage::FormatSpecifier, QString> DSCMessage::m_formatSpecifierShortStrings = {
 | |
|     {GEOGRAPHIC_CALL, "AREA"},
 | |
|     {DISTRESS_ALERT,  "DIS"},
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|     {GROUP_CALL,      "GRP"},
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|     {ALL_SHIPS,       "ALL"},
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|     {SELECTIVE_CALL,  "SEL"},
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|     {AUTOMATIC_CALL,  "AUT"}
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| };
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| 
 | |
| QMap<DSCMessage::Category, QString> DSCMessage::m_categoryStrings = {
 | |
|     {ROUTINE,       "Routine"},
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|     {SAFETY,        "Safety"},
 | |
|     {URGENCY,       "Urgency"},
 | |
|     {DISTRESS,      "Distress"}
 | |
| };
 | |
| 
 | |
| QMap<DSCMessage::Category, QString> DSCMessage::m_categoryShortStrings = {
 | |
|     {ROUTINE,       "RTN"},
 | |
|     {SAFETY,        "SAF"},
 | |
|     {URGENCY,       "URG"},
 | |
|     {DISTRESS,      "DIS"}
 | |
| };
 | |
| 
 | |
| QMap<DSCMessage::FirstTelecommand, QString> DSCMessage::m_telecommand1Strings = {
 | |
|     {F3E_G3E_ALL_MODES_TP,  "F3E (FM speech)/G3E (phase modulated speech) all modes telephony"},
 | |
|     {F3E_G3E_DUPLEX_TP,     "F3E (FM speech)/G3E (phase modulated speech) duplex telephony"},
 | |
|     {POLLING,               "Polling"},
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|     {UNABLE_TO_COMPLY,      "Unable to comply"},
 | |
|     {END_OF_CALL,           "End of call"},
 | |
|     {DATA,                  "Data"},
 | |
|     {J3E_TP,                "J3E (SSB) telephony"},
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|     {DISTRESS_ACKNOWLEDGEMENT, "Distress acknowledgement"},
 | |
|     {DISTRESS_ALERT_RELAY,  "Distress alert relay"},
 | |
|     {F1B_J2B_TTY_FEC,       "F1B (FSK) J2B (FSK via SSB) TTY FEC"},
 | |
|     {F1B_J2B_TTY_AQR,       "F1B (FSK) J2B (FSK via SSB) TTY AQR"},
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|     {TEST,                  "Test"},
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|     {POSITION_UPDATE,       "Position update"},
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|     {NO_INFORMATION,        "No information"}
 | |
| };
 | |
| 
 | |
| QMap<DSCMessage::FirstTelecommand, QString> DSCMessage::m_telecommand1ShortStrings = {
 | |
|     {F3E_G3E_ALL_MODES_TP,  "F3E/G3E"},
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|     {F3E_G3E_DUPLEX_TP,     "F3E/G3E, Duplex TP"},
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|     {POLLING,               "POLL"},
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|     {UNABLE_TO_COMPLY,      "UNABLE TO COMPLY"},
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|     {END_OF_CALL,           "EOC"},
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|     {DATA,                  "DATA"},
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|     {J3E_TP,                "J3E TP"},
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|     {DISTRESS_ACKNOWLEDGEMENT, "DISTRESS ACK"},
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|     {DISTRESS_ALERT_RELAY,  "DISTRESS RELAY"},
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|     {F1B_J2B_TTY_FEC,       "F1B/J2B TTY-FEC"},
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|     {F1B_J2B_TTY_AQR,       "F1B/J2B TTY-ARQ"},
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|     {TEST,                  "TEST"},
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|     {POSITION_UPDATE,       "POSUPD"},
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|     {NO_INFORMATION,        "NOINF"}
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| };
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| 
 | |
| QMap<DSCMessage::SecondTelecommand, QString> DSCMessage::m_telecommand2Strings = {
 | |
|     {NO_REASON,                 "No reason"},
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|     {CONGESTION,                "Congestion at switching centre"},
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|     {BUSY,                      "Busy"},
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|     {QUEUE,                     "Queue indication"},
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|     {BARRED,                    "Station barred"},
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|     {NO_OPERATOR,               "No operator available"},
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|     {OPERATOR_UNAVAILABLE,      "Operator temporarily unavailable"},
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|     {EQUIPMENT_DISABLED,        "Equipment disabled"},
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|     {UNABLE_TO_USE_CHANNEL,     "Unable to use proposed channel"},
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|     {UNABLE_TO_USE_MODE,        "Unable to use proposed mode"},
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|     {NOT_PARTIES_TO_CONFLICT,   "Ships and aircraft of States not parties to an armed conflict"},
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|     {MEDICAL_TRANSPORTS,        "Medical transports"},
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|     {PAY_PHONE,                 "Pay-phone/public call office"},
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|     {FAX,                       "Facsimile"},
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|     {NO_INFORMATION_2,          "No information"}
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| };
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| 
 | |
| QMap<DSCMessage::SecondTelecommand, QString> DSCMessage::m_telecommand2ShortStrings = {
 | |
|     {NO_REASON,                 "NO REASON GIVEN"},
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|     {CONGESTION,                "CONGESTION AT MARITIME CENTRE"},
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|     {BUSY,                      "BUSY"},
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|     {QUEUE,                     "QUEUE INDICATION"},
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|     {BARRED,                    "STATION BARRED"},
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|     {NO_OPERATOR,               "NO OPERATOR AVAILABLE"},
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|     {OPERATOR_UNAVAILABLE,      "OPERATOR TEMPORARILY UNAVAILABLE"},
 | |
|     {EQUIPMENT_DISABLED,        "EQUIPMENT DISABLED"},
 | |
|     {UNABLE_TO_USE_CHANNEL,     "UNABLE TO USE PROPOSED CHANNEL"},
 | |
|     {UNABLE_TO_USE_MODE,        "UNABLE TO USE PROPOSED MODE"},
 | |
|     {NOT_PARTIES_TO_CONFLICT,   "SHIPS/AIRCRAFT OF STATES NOT PARTIES TO ARMED CONFLICT"},
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|     {MEDICAL_TRANSPORTS,        "MEDICAL TRANSPORTS"},
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|     {PAY_PHONE,                 "PAY-PHONE/PUBLIC CALL OFFICE"},
 | |
|     {FAX,                       "FAX/DATA ACCORDING ITU-R M1081"},
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|     {NO_INFORMATION_2,          "NOINF"}
 | |
| };
 | |
| 
 | |
| QMap<DSCMessage::DistressNature, QString> DSCMessage::m_distressNatureStrings = {
 | |
|     {FIRE,              "Fire, explosion"},
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|     {FLOODING,          "Flooding"},
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|     {COLLISION,         "Collision"},
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|     {GROUNDING,         "Grounding"},
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|     {LISTING,           "Listing"},
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|     {SINKING,           "Sinking"},
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|     {ADRIFT,            "Adrift"},
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|     {UNDESIGNATED,      "Undesignated"},
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|     {ABANDONING_SHIP,   "Abandoning ship"},
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|     {PIRACY,            "Piracy, armed attack"},
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|     {MAN_OVERBOARD,     "Man overboard"},
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|     {EPIRB,             "EPIRB"}
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| };
 | |
| 
 | |
| QMap<DSCMessage::EndOfSignal, QString> DSCMessage::m_endOfSignalStrings = {
 | |
|     {REQ, "Req ACK"},
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|     {ACK, "ACK"},
 | |
|     {EOS, "EOS"}
 | |
| };
 | |
| 
 | |
| QMap<DSCMessage::EndOfSignal, QString> DSCMessage::m_endOfSignalShortStrings = {
 | |
|     {REQ, "REQ"},
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|     {ACK, "ACK"},
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|     {EOS, "EOS"}
 | |
| };
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| 
 | |
| DSCMessage::DSCMessage(const QByteArray& data, QDateTime dateTime) :
 | |
|     m_dateTime(dateTime),
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|     m_data(data)
 | |
| {
 | |
|     decode(data);
 | |
| }
 | |
| 
 | |
| QString DSCMessage::toString(const QString separator) const
 | |
| {
 | |
|     QStringList s;
 | |
| 
 | |
|     s.append(QString("Format specifier: %1").arg(formatSpecifier()));
 | |
| 
 | |
|     if (m_hasAddress) {
 | |
|         s.append(QString("Address: %1").arg(m_address));
 | |
|     }
 | |
|     if (m_hasCategory) {
 | |
|         s.append(QString("Category: %1").arg(category()));
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|     }
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| 
 | |
|     s.append(QString("Self Id: %1").arg(m_selfId));
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| 
 | |
|     if (m_hasTelecommand1) {
 | |
|         s.append(QString("Telecommand 1: %1").arg(telecommand1(m_telecommand1)));
 | |
|     }
 | |
|     if (m_hasTelecommand2) {
 | |
|         s.append(QString("Telecommand 2: %1").arg(telecommand2(m_telecommand2)));
 | |
|     }
 | |
| 
 | |
|     if (m_hasDistressId) {
 | |
|         s.append(QString("Distress Id: %1").arg(m_distressId));
 | |
|     }
 | |
|     if (m_hasDistressNature)
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|     {
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|         s.append(QString("Distress nature: %1").arg(distressNature(m_distressNature)));
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|         s.append(QString("Distress coordinates: %1").arg(m_position));
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|     }
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|     else if (m_hasPosition)
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|     {
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|         s.append(QString("Position: %1").arg(m_position));
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|     }
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| 
 | |
|     if (m_hasFrequency1) {
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|         s.append(QString("RX Frequency: %1Hz").arg(m_frequency1));
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|     }
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|     if (m_hasChannel1) {
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|         s.append(QString("RX Channel: %1").arg(m_channel1));
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|     }
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|     if (m_hasFrequency2) {
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|         s.append(QString("TX Frequency: %1Hz").arg(m_frequency2));
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|     }
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|     if (m_hasChannel2) {
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|         s.append(QString("TX Channel: %1").arg(m_channel2));
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|     }
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|     if (m_hasNumber) {
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|         s.append(QString("Phone Number: %1").arg(m_number));
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|     }
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| 
 | |
|     if (m_hasTime) {
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|         s.append(QString("Time: %1").arg(m_time.toString()));
 | |
|     }
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|     if (m_hasSubsequenceComms) {
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|         s.append(QString("Subsequent comms: %1").arg(telecommand1(m_subsequenceComms)));
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|     }
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| 
 | |
|     return s.join(separator);
 | |
| }
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| 
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| QString DSCMessage::toYaddNetFormat(const QString& id, qint64 frequency) const
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| {
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|     QStringList s;
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| 
 | |
|     // rx_id
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|     s.append(QString("[%1]").arg(id));
 | |
|     // rx_freq
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|     float frequencyKHZ = frequency / 1000.0f;
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|     s.append(QString("%1").arg(frequencyKHZ, 0, 'f', 1));
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|     // fmt
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|     s.append(formatSpecifier(true));
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|     // to
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|     if (m_hasAddress)
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|     {
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|         if (m_formatSpecifier == GEOGRAPHIC_CALL)
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|         {
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|             char ns = m_addressLatitude >= 0 ? 'N' : 'S';
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|             char ew = m_addressLongitude >= 0 ? 'E' : 'W';
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|             int lat = abs(m_addressLatitude);
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|             int lon = abs(m_addressLongitude);
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|             s.append(QString("AREA %2%1%6=>%4%1 %3%1%7=>%5%1")
 | |
|                                 .arg(QChar(0xb0))  // degree
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|                                 .arg(lat, 2, 10, QChar('0'))
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|                                 .arg(lon, 3, 10, QChar('0'))
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|                                 .arg(m_addressLatAngle, 2, 10, QChar('0'))
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|                                 .arg(m_addressLonAngle, 2, 10, QChar('0'))
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|                                 .arg(ns)
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|                                 .arg(ew));
 | |
|         }
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|         else
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|         {
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|             s.append(m_address);
 | |
|         }
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|     }
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|     else
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|     {
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|         s.append("");
 | |
|     }
 | |
|     // cat
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|     s.append(category(true));
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|     // from
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|     s.append(m_selfId);
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| 
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|     // tc1
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|     if (m_hasTelecommand1) {
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|         s.append(telecommand1(m_telecommand1, true));
 | |
|     } else {
 | |
|         s.append("--");
 | |
|     }
 | |
|     // tc2
 | |
|     if (m_hasTelecommand2) {
 | |
|         s.append(telecommand2(m_telecommand2, true));
 | |
|     } else {
 | |
|         s.append("--");
 | |
|     }
 | |
|     // distress fields don't appear to be used!
 | |
|     // freq
 | |
|     if (m_hasFrequency1 && m_hasFrequency2) {
 | |
|         s.append(QString("%1/%2KHz").arg(m_frequency1/1000.0, 7, 'f', 1, QChar('0')).arg(m_frequency2/1000.0, 7, 'f', 1, QChar('0')));
 | |
|     } else if (m_hasFrequency1) {
 | |
|         s.append(QString("%1KHz").arg(m_frequency1/1000.0, 7, 'f', 1, QChar('0')));
 | |
|     } else if (m_hasFrequency2) {
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|         s.append(QString("%1KHz").arg(m_frequency2/1000.0, 7, 'f', 1, QChar('0')));
 | |
|     } else if (m_hasChannel1 && m_hasChannel2) {
 | |
|         s.append(QString("%1/%2").arg(m_channel1).arg(m_channel2));
 | |
|     } else if (m_hasChannel1) {
 | |
|         s.append(QString("%1").arg(m_channel1));
 | |
|     } else if (m_hasChannel2) {
 | |
|         s.append(QString("%1").arg(m_channel2));
 | |
|     } else {
 | |
|         s.append("--");
 | |
|     }
 | |
|     // pos
 | |
|     if (m_hasPosition) {
 | |
|         s.append(m_position);   // FIXME: Format??
 | |
|     } else {
 | |
|         s.append("--");         // Sometimes this is " -- ". in YaDD Why?
 | |
|     }
 | |
| 
 | |
|     // eos
 | |
|     s.append(endOfSignal(m_eos, true));
 | |
|     // ecc
 | |
|     s.append(QString("ECC %1 %2").arg(m_calculatedECC).arg(m_eccOk ? "OK" : "ERR"));
 | |
| 
 | |
|     return s.join(";");
 | |
| }
 | |
| 
 | |
| QString DSCMessage::formatSpecifier(bool shortString) const
 | |
| {
 | |
|     if (shortString)
 | |
|     {
 | |
|         if (m_formatSpecifierShortStrings.contains(m_formatSpecifier)) {
 | |
|             return m_formatSpecifierShortStrings[m_formatSpecifier];
 | |
|         } else {
 | |
|             return QString("UNK/ERR").arg(m_formatSpecifier);
 | |
|         }
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         if (m_formatSpecifierStrings.contains(m_formatSpecifier)) {
 | |
|             return m_formatSpecifierStrings[m_formatSpecifier];
 | |
|         } else {
 | |
|             return QString("Unknown (%1)").arg(m_formatSpecifier);
 | |
|         }
 | |
|     }
 | |
| }
 | |
| 
 | |
| 
 | |
| QString DSCMessage::category(bool shortString) const
 | |
| {
 | |
|     if (shortString)
 | |
|     {
 | |
|         if (m_categoryShortStrings.contains(m_category)) {
 | |
|             return m_categoryShortStrings[m_category];
 | |
|         } else {
 | |
|             return QString("UNK/ERR").arg(m_category);
 | |
|         }
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         if (!m_hasCategory) {
 | |
|             return "N/A";
 | |
|         } else if (m_categoryStrings.contains(m_category)) {
 | |
|             return m_categoryStrings[m_category];
 | |
|         } else {
 | |
|             return QString("Unknown (%1)").arg(m_category);
 | |
|         }
 | |
|     }
 | |
| }
 | |
| 
 | |
| QString DSCMessage::telecommand1(FirstTelecommand telecommand, bool shortString)
 | |
| {
 | |
|     if (shortString)
 | |
|     {
 | |
|         if (m_telecommand1ShortStrings.contains(telecommand)) {
 | |
|             return m_telecommand1ShortStrings[telecommand];
 | |
|         } else {
 | |
|             return QString("UNK/ERR").arg(telecommand);
 | |
|         }
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         if (m_telecommand1Strings.contains(telecommand)) {
 | |
|             return m_telecommand1Strings[telecommand];
 | |
|         } else {
 | |
|             return QString("Unknown (%1)").arg(telecommand);
 | |
|         }
 | |
|     }
 | |
| }
 | |
| 
 | |
| QString DSCMessage::telecommand2(SecondTelecommand telecommand, bool shortString)
 | |
| {
 | |
|     if (shortString)
 | |
|     {
 | |
|         if (m_telecommand2ShortStrings.contains(telecommand)) {
 | |
|             return m_telecommand2ShortStrings[telecommand];
 | |
|         } else {
 | |
|             return QString("UNK/ERR").arg(telecommand);
 | |
|         }
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         if (m_telecommand2Strings.contains(telecommand)) {
 | |
|             return m_telecommand2Strings[telecommand];
 | |
|         } else {
 | |
|             return QString("Unknown (%1)").arg(telecommand);
 | |
|         }
 | |
|     }
 | |
| }
 | |
| 
 | |
| QString DSCMessage::distressNature(DistressNature nature)
 | |
| {
 | |
|     if (m_distressNatureStrings.contains(nature)) {
 | |
|         return m_distressNatureStrings[nature];
 | |
|     } else {
 | |
|         return QString("Unknown (%1)").arg(nature);
 | |
|     }
 | |
| }
 | |
| 
 | |
| QString DSCMessage::endOfSignal(EndOfSignal eos, bool shortString)
 | |
| {
 | |
|     if (shortString)
 | |
|     {
 | |
|         if (m_endOfSignalShortStrings.contains(eos)) {
 | |
|             return m_endOfSignalShortStrings[eos];
 | |
|         } else {
 | |
|             return QString("UNK/ERR").arg(eos);
 | |
|         }
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         if (m_endOfSignalStrings.contains(eos)) {
 | |
|             return m_endOfSignalStrings[eos];
 | |
|         } else {
 | |
|             return QString("Unknown (%1)").arg(eos);
 | |
|         }
 | |
|     }
 | |
| }
 | |
| 
 | |
| 
 | |
| QString DSCMessage::symbolsToDigits(const QByteArray data, int startIdx, int length)
 | |
| {
 | |
|     QString s;
 | |
| 
 | |
|     for (int i = 0; i < length; i++)
 | |
|     {
 | |
|         QString digits = QString("%1").arg((int)data[startIdx+i], 2, 10, QChar('0'));
 | |
|         s = s.append(digits);
 | |
|     }
 | |
| 
 | |
|     return s;
 | |
| }
 | |
| 
 | |
| QString DSCMessage::formatCoordinates(int latitude, int longitude)
 | |
| {
 | |
|     QString lat, lon;
 | |
|     if (latitude >= 0) {
 | |
|         lat = QString("%1%2N").arg(latitude).arg(QChar(0xb0));
 | |
|     } else {
 | |
|         lat = QString("%1%2S").arg(-latitude).arg(QChar(0xb0));
 | |
|     }
 | |
|     if (longitude >= 0) {
 | |
|         lon = QString("%1%2E").arg(longitude).arg(QChar(0xb0));
 | |
|     } else {
 | |
|         lon = QString("%1%2W").arg(-longitude).arg(QChar(0xb0));
 | |
|     }
 | |
|     return QString("%1 %2").arg(lat).arg(lon);
 | |
| }
 | |
| 
 | |
| void DSCMessage::decode(const QByteArray& data)
 | |
| {
 | |
|     int idx = 0;
 | |
| 
 | |
|     // Format specifier
 | |
|     m_formatSpecifier = (FormatSpecifier) data[idx++];
 | |
|     m_formatSpecifierMatch = m_formatSpecifier == data[idx++];
 | |
| 
 | |
|     // Address and category
 | |
|     if (m_formatSpecifier != DISTRESS_ALERT)
 | |
|     {
 | |
|         if (m_formatSpecifier != ALL_SHIPS)
 | |
|         {
 | |
|             m_address = symbolsToDigits(data, idx, 5);
 | |
|             idx += 5;
 | |
|             m_hasAddress = true;
 | |
| 
 | |
|             if (m_formatSpecifier == SELECTIVE_CALL)
 | |
|             {
 | |
|                 m_address = formatAddress(m_address);
 | |
|             }
 | |
|             else if (m_formatSpecifier == GEOGRAPHIC_CALL)
 | |
|             {
 | |
|                 // Address defines a geographic rectangle. We have NW coord + 2 angles
 | |
|                 QChar azimuthSector = m_address[0];
 | |
|                 m_addressLatitude = m_address[1].digitValue() * 10 + m_address[2].digitValue(); // In degrees
 | |
|                 m_addressLongitude = m_address[3].digitValue() * 100 + m_address[4].digitValue() * 10 + m_address[5].digitValue(); // In degrees
 | |
|                 switch (azimuthSector.toLatin1())
 | |
|                 {
 | |
|                 case '0':   // NE
 | |
|                     break;
 | |
|                 case '1':   // NW
 | |
|                     m_addressLongitude = -m_addressLongitude;
 | |
|                     break;
 | |
|                 case '2':   // SE
 | |
|                     m_addressLatitude = -m_addressLatitude;
 | |
|                     break;
 | |
|                 case '3':   // SW
 | |
|                     m_addressLongitude = -m_addressLongitude;
 | |
|                     m_addressLatitude = -m_addressLatitude;
 | |
|                     break;
 | |
|                 default:
 | |
|                     break;
 | |
|                 }
 | |
|                 m_addressLatAngle = m_address[6].digitValue() * 10 + m_address[7].digitValue();
 | |
|                 m_addressLonAngle = m_address[8].digitValue() * 10 + m_address[9].digitValue();
 | |
| 
 | |
|                 int latitude2 = m_addressLatitude + m_addressLatAngle;
 | |
|                 int longitude2 = m_addressLongitude + m_addressLonAngle;
 | |
| 
 | |
|                 /*m_address = QString("Lat %2%1 Lon %3%1 %4%5%6%1 %4%7%8%1")
 | |
|                                 .arg(QChar(0xb0))  // degree
 | |
|                                 .arg(m_addressLatitude)
 | |
|                                 .arg(m_addressLongitude)
 | |
|                                 .arg(QChar(0x0394)) // delta
 | |
|                                 .arg(QChar(0x03C6)) // phi
 | |
|                                 .arg(m_addressLatAngle)
 | |
|                                 .arg(QChar(0x03BB)) // lambda
 | |
|                                 .arg(m_addressLonAngle);*/
 | |
|                 m_address = QString("%1 - %2")
 | |
|                             .arg(formatCoordinates(m_addressLatitude, m_addressLongitude))
 | |
|                             .arg(formatCoordinates(latitude2, longitude2));
 | |
|             }
 | |
|         }
 | |
|         else
 | |
|         {
 | |
|             m_hasAddress = false;
 | |
|         }
 | |
|         m_category = (Category) data[idx++];
 | |
|         m_hasCategory = true;
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         m_hasAddress = false;
 | |
|         m_hasCategory = true;
 | |
|     }
 | |
| 
 | |
|     // Self Id
 | |
|     m_selfId = symbolsToDigits(data, idx, 5);
 | |
|     m_selfId = formatAddress(m_selfId);
 | |
|     idx += 5;
 | |
| 
 | |
|     // Telecommands
 | |
|     if (m_formatSpecifier != DISTRESS_ALERT)
 | |
|     {
 | |
|         m_telecommand1 = (FirstTelecommand) data[idx++];
 | |
|         m_hasTelecommand1 = true;
 | |
| 
 | |
|         if (m_category != DISTRESS)  // Not Distress Alert Ack / Relay
 | |
|         {
 | |
|             m_telecommand2 = (SecondTelecommand) data[idx++];
 | |
|             m_hasTelecommand2 = true;
 | |
|         }
 | |
|         else
 | |
|         {
 | |
|             m_hasTelecommand2 = false;
 | |
|         }
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|          m_hasTelecommand1 = false;
 | |
|          m_hasTelecommand2 = false;
 | |
|     }
 | |
| 
 | |
|     // ID of source of distress for relays and acks
 | |
|     if (m_hasCategory && m_category == DISTRESS)
 | |
|     {
 | |
|         m_distressId = symbolsToDigits(data, idx, 5);
 | |
|         m_distressId = formatAddress(m_distressId);
 | |
|         idx += 5;
 | |
|         m_hasDistressId = true;
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         m_hasDistressId = false;
 | |
|     }
 | |
| 
 | |
|     if (m_formatSpecifier == DISTRESS_ALERT)
 | |
|     {
 | |
|         m_distressNature = (DistressNature) data[idx++];
 | |
|         m_position = formatCoordinates(symbolsToDigits(data, idx, 5));
 | |
|         idx += 5;
 | |
|         m_hasDistressNature = true;
 | |
|         m_hasPosition = true;
 | |
| 
 | |
|         m_hasFrequency1 = false;
 | |
|         m_hasChannel1 = false;
 | |
|         m_hasFrequency2 = false;
 | |
|         m_hasChannel2 = false;
 | |
|     }
 | |
|     else if (m_hasCategory && (m_category != DISTRESS))
 | |
|     {
 | |
|         m_hasDistressNature = false;
 | |
|         // Frequency or position
 | |
|         if (data[idx] == 55)
 | |
|         {
 | |
|             // Position 6
 | |
|             m_position = formatCoordinates(symbolsToDigits(data, idx, 5));
 | |
|             idx += 5;
 | |
|             m_hasPosition = true;
 | |
| 
 | |
|             m_hasFrequency1 = false;
 | |
|             m_hasChannel1 = false;
 | |
|             m_hasFrequency2 = false;
 | |
|             m_hasChannel2 = false;
 | |
|         }
 | |
|         else
 | |
|         {
 | |
|             m_hasPosition = false;
 | |
|             // Frequency
 | |
|             m_frequency1 = 0;
 | |
|             decodeFrequency(data, idx, m_frequency1, m_channel1);
 | |
|             m_hasFrequency1 = m_frequency1 != 0;
 | |
|             m_hasChannel1 = !m_channel1.isEmpty();
 | |
| 
 | |
|             if (m_formatSpecifier != AUTOMATIC_CALL)
 | |
|             {
 | |
|                 m_frequency2 = 0;
 | |
|                 decodeFrequency(data, idx, m_frequency2, m_channel2);
 | |
|                 m_hasFrequency2 = m_frequency2 != 0;
 | |
|                 m_hasChannel2 = !m_channel2.isEmpty();
 | |
|             }
 | |
|             else
 | |
|             {
 | |
|                 m_hasFrequency2 = false;
 | |
|                 m_hasChannel2 = false;
 | |
|             }
 | |
|         }
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         m_hasDistressNature = false;
 | |
|         m_hasPosition = false;
 | |
|         m_hasFrequency1 = false;
 | |
|         m_hasChannel1 = false;
 | |
|         m_hasFrequency2 = false;
 | |
|         m_hasChannel2 = false;
 | |
|     }
 | |
| 
 | |
|     if (m_formatSpecifier == AUTOMATIC_CALL)
 | |
|     {
 | |
|         signed char oddEven = data[idx++];
 | |
|         int len = data.size() - idx - 2; // EOS + ECC
 | |
|         m_number = symbolsToDigits(data, idx, len);
 | |
|         idx += len;
 | |
|         if (oddEven == 105) { // Is number an odd number?
 | |
|             m_number = m_number.mid(1); // Drop leading digit (which should be a 0)
 | |
|         }
 | |
|         m_hasNumber = true;
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         m_hasNumber = false;
 | |
|     }
 | |
| 
 | |
|     // Time
 | |
|     if (   (m_formatSpecifier == DISTRESS_ALERT)
 | |
|         || (m_hasCategory && (m_category == DISTRESS))
 | |
|         //|| (m_formatSpecifier == SELECTIVE_CALL) && (m_category == SAFETY) && (m_telecommand1 == POSITION_UPDATE) && (m_telecommand2 == 126) && (m_frequency == pos4))
 | |
|        )
 | |
|     {
 | |
|         // 8 8 8 8 for no time
 | |
|         QString time = symbolsToDigits(data, idx, 2);
 | |
|         if (time != "8888")
 | |
|         {
 | |
|             m_time = QTime(time.left(2).toInt(), time.right(2).toInt());
 | |
|             m_hasTime = true;
 | |
|         }
 | |
|         else
 | |
|         {
 | |
|             m_hasTime = false;
 | |
|         }
 | |
|         // FIXME: Convert to QTime?
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         m_hasTime = false;
 | |
|     }
 | |
| 
 | |
|     // Subsequent communications
 | |
|     if ((m_formatSpecifier == DISTRESS_ALERT) || (m_hasCategory && (m_category == DISTRESS)))
 | |
|     {
 | |
|         m_subsequenceComms = (FirstTelecommand)data[idx++];
 | |
|         m_hasSubsequenceComms = true;
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         m_hasSubsequenceComms = false;
 | |
|     }
 | |
| 
 | |
|     m_eos = (EndOfSignal) data[idx++];
 | |
|     m_ecc = data[idx++];
 | |
| 
 | |
|     checkECC(data);
 | |
| 
 | |
|     // Indicate message as being invalid if any unexpected data, too long, or ECC didn't match
 | |
|     if (   m_formatSpecifierStrings.contains(m_formatSpecifier)
 | |
|         && (!m_hasCategory || (m_hasCategory && m_categoryStrings.contains(m_category)))
 | |
|         && (!m_hasTelecommand1 || (m_hasTelecommand1 && m_telecommand1Strings.contains(m_telecommand1)))
 | |
|         && (!m_hasTelecommand2 || (m_hasTelecommand2 && m_telecommand2Strings.contains(m_telecommand2)))
 | |
|         && (!m_hasDistressNature || (m_hasDistressNature && m_distressNatureStrings.contains(m_distressNature)))
 | |
|         && m_endOfSignalStrings.contains(m_eos)
 | |
|         && (!data.contains(-1))
 | |
|         && (data.size() < DSCDecoder::m_maxBytes)
 | |
|         && m_eccOk
 | |
|        ) {
 | |
|         m_valid = true;
 | |
|     } else {
 | |
|         m_valid = false;
 | |
|     }
 | |
| 
 | |
| }
 | |
| 
 | |
| void DSCMessage::checkECC(const QByteArray& data)
 | |
| {
 | |
|     m_calculatedECC = 0;
 | |
|     // Only use one format specifier and one EOS
 | |
|     for (int i = 1; i < data.size() - 1; i++) {
 | |
|         m_calculatedECC ^= data[i];
 | |
|     }
 | |
|     m_eccOk = m_calculatedECC == m_ecc;
 | |
| }
 | |
| 
 | |
| void DSCMessage::decodeFrequency(const QByteArray& data, int& idx, int& frequency, QString& channel)
 | |
| {
 | |
|     // No frequency information is indicated by 126 repeated 3 times
 | |
|     if ((data[idx] == 126) && (data[idx+1] == 126) && (data[idx+2] == 126))
 | |
|     {
 | |
|         idx += 3;
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     // Extract frequency digits
 | |
|     QString s = symbolsToDigits(data, idx, 3);
 | |
|     idx += 3;
 | |
|     if (s[0] == '4')
 | |
|     {
 | |
|         s = s.append(symbolsToDigits(data, idx, 1));
 | |
|         idx++;
 | |
|     }
 | |
| 
 | |
|     if ((s[0] == '0') || (s[0] == '1') || (s[0] == '2'))
 | |
|     {
 | |
|         frequency = s.toInt() * 100;
 | |
|     }
 | |
|     else if (s[0] == '3')
 | |
|     {
 | |
|         channel = "CH" + s.mid(1); // HF/MF
 | |
|     }
 | |
|     else if (s[0] == '4')
 | |
|     {
 | |
|         frequency = s.mid(1).toInt() * 10; // Frequency in multiples of 10Hz
 | |
|     }
 | |
|     else if (s[0] == '9')
 | |
|     {
 | |
|         channel = "CH" + s.mid(2) + "VHF";  // VHF
 | |
|     }
 | |
| }
 | |
| 
 | |
| QString DSCMessage::formatAddress(const QString &address) const
 | |
| {
 | |
|     // First 9 digits should be MMSI
 | |
|     // Last digit should always be 0, except for ITU-R M.1080, which allows 10th digit to specify different equipement on same vessel
 | |
|     if (address.right(1) == "0") {
 | |
|         return address.left(9);
 | |
|     } else {
 | |
|         return QString("%1-%2").arg(address.left(9)).arg(address.right(1));
 | |
|     }
 | |
| }
 | |
| 
 | |
| QString DSCMessage::formatCoordinates(const QString& coords)
 | |
| {
 | |
|     if (coords == "9999999999")
 | |
|     {
 | |
|         return "Not available";
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         QChar quadrant = coords[0];
 | |
|         QString latitude = QString("%1%3%2\'")
 | |
|             .arg(coords.mid(1, 2))
 | |
|             .arg(coords.mid(3, 2))
 | |
|             .arg(QChar(0xb0));
 | |
|         QString longitude = QString("%1%3%2\'")
 | |
|             .arg(coords.mid(1, 3))
 | |
|             .arg(coords.mid(4, 2))
 | |
|             .arg(QChar(0xb0));
 | |
|         switch (quadrant.toLatin1())
 | |
|         {
 | |
|         case '0':
 | |
|             latitude = latitude.append('N');
 | |
|             longitude = longitude.append('E');
 | |
|             break;
 | |
|         case '1':
 | |
|             latitude = latitude.append('N');
 | |
|             longitude = longitude.append('W');
 | |
|             break;
 | |
|         case '2':
 | |
|             latitude = latitude.append('S');
 | |
|             longitude = longitude.append('E');
 | |
|             break;
 | |
|         case '3':
 | |
|             latitude = latitude.append('S');
 | |
|             longitude = longitude.append('W');
 | |
|             break;
 | |
|         }
 | |
|         return QString("%1 %2").arg(latitude).arg(longitude);
 | |
|     }
 | |
| }
 | |
| 
 | |
| // Doesn't include 125 111 125 as these will have be detected already, in DSDDemodSink
 | |
| const signed char DSCDecoder::m_expectedSymbols[] = {
 | |
|     110,
 | |
|     125, 109,
 | |
|     125, 108,
 | |
|     125, 107,
 | |
|     125, 106
 | |
| };
 | |
| 
 | |
| int DSCDecoder::m_maxBytes = 40; // Max bytes in any message
 | |
| 
 | |
| void DSCDecoder::init(int offset)
 | |
| {
 | |
|     if (offset == 0)
 | |
|     {
 | |
|         m_state = FILL_DX;
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         m_phaseIdx = offset;
 | |
|         m_state = PHASING;
 | |
|     }
 | |
|     m_idx = 0;
 | |
|     m_errors = 0;
 | |
|     m_bytes = QByteArray();
 | |
|     m_eos = false;
 | |
| }
 | |
| 
 | |
| bool DSCDecoder::decodeSymbol(signed char symbol)
 | |
| {
 | |
|     bool ret = false;
 | |
| 
 | |
|     switch (m_state)
 | |
|     {
 | |
|     case PHASING:
 | |
|         // Check if received phasing signals are as expected
 | |
|         if (symbol != m_expectedSymbols[9-m_phaseIdx]) {
 | |
|             m_errors++;
 | |
|         }
 | |
|         m_phaseIdx--;
 | |
|         if (m_phaseIdx == 0) {
 | |
|             m_state = FILL_DX;
 | |
|         }
 | |
|         break;
 | |
| 
 | |
|     case FILL_DX:
 | |
|         // Fill up buffer
 | |
|         m_buf[m_idx++] = symbol;
 | |
|         if (m_idx == BUFFER_SIZE)
 | |
|         {
 | |
|             m_state = RX;
 | |
|             m_idx = 0;
 | |
|         }
 | |
|         else
 | |
|         {
 | |
|             m_state = FILL_RX;
 | |
|         }
 | |
|         break;
 | |
| 
 | |
|     case FILL_RX:
 | |
|         if (   ((m_idx == 1) && (symbol != 106))
 | |
|             || ((m_idx == 2) && (symbol != 105))
 | |
|            )
 | |
|         {
 | |
|             m_errors++;
 | |
|         }
 | |
|         m_state = FILL_DX;
 | |
|         break;
 | |
| 
 | |
|     case RX:
 | |
|         {
 | |
|             signed char a = selectSymbol(m_buf[m_idx], symbol);
 | |
| 
 | |
|             if (DSCMessage::m_endOfSignalStrings.contains((DSCMessage::EndOfSignal) a)) {
 | |
|                 m_state = DX_EOS;
 | |
|             } else {
 | |
|                 m_state = DX;
 | |
|             }
 | |
| 
 | |
|             if (m_bytes.size() > m_maxBytes)
 | |
|             {
 | |
|                 ret = true;
 | |
|                 m_state = NO_EOS;
 | |
|             }
 | |
|         }
 | |
|         break;
 | |
| 
 | |
|     case DX:
 | |
|         // Save received character in buffer
 | |
|         m_buf[m_idx] = symbol;
 | |
|         m_idx = (m_idx + 1) % BUFFER_SIZE;
 | |
|         m_state = RX;
 | |
|         break;
 | |
| 
 | |
|     case DX_EOS:
 | |
|         // Save, EOS symbol
 | |
|         m_buf[m_idx] = symbol;
 | |
|         m_idx = (m_idx + 1) % BUFFER_SIZE;
 | |
|         m_state = RX_EOS;
 | |
|         break;
 | |
| 
 | |
|     case RX_EOS:
 | |
|         selectSymbol(m_buf[m_idx], symbol);
 | |
|         m_state = DONE;
 | |
|         ret = true;
 | |
|         break;
 | |
| 
 | |
|     case DONE:
 | |
|     case NO_EOS:
 | |
|         break;
 | |
| 
 | |
|     }
 | |
| 
 | |
|     return ret;
 | |
| }
 | |
| 
 | |
| // Reverse order of bits in a byte
 | |
| unsigned char DSCDecoder::reverse(unsigned char b)
 | |
| {
 | |
|    b = (b & 0xF0) >> 4 | (b & 0x0F) << 4;
 | |
|    b = (b & 0xCC) >> 2 | (b & 0x33) << 2;
 | |
|    b = (b & 0xAA) >> 1 | (b & 0x55) << 1;
 | |
|    return b;
 | |
| }
 | |
| 
 | |
| // Convert 10 bits to a symbol
 | |
| // Returns -1 if error detected
 | |
| signed char DSCDecoder::bitsToSymbol(unsigned int bits)
 | |
| {
 | |
|     signed char data = reverse(bits >> 3) >> 1;
 | |
|     int zeros = 7-popcount(data);
 | |
|     int expectedZeros = bits & 0x7;
 | |
|     if (zeros == expectedZeros) {
 | |
|         return data;
 | |
|     } else {
 | |
|         return -1;
 | |
|     }
 | |
| }
 | |
| 
 | |
| // Decode 10-bits to symbols then remove errors using repeated symbols
 | |
| bool DSCDecoder::decodeBits(int bits)
 | |
| {
 | |
|     signed char symbol = bitsToSymbol(bits);
 | |
|     //qDebug() << "Bits2sym: " << Qt::hex << bits << Qt::hex << symbol;
 | |
|     return decodeSymbol(symbol);
 | |
| }
 | |
| 
 | |
| // Select time diversity symbol without errors
 | |
| signed char DSCDecoder::selectSymbol(signed char dx, signed char rx)
 | |
| {
 | |
|     signed char s;
 | |
|     if (dx != -1)
 | |
|     {
 | |
|         s = dx;  // First received character has no detectable error
 | |
|         if (dx != rx) {
 | |
|             m_errors++;
 | |
|         }
 | |
|     }
 | |
|     else if (rx != -1)
 | |
|     {
 | |
|         s = rx;  // Second received character has no detectable error
 | |
|         m_errors++;
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         s = '*'; // Both received characters have errors
 | |
|         m_errors += 2;
 | |
|     }
 | |
|     m_bytes.append(s);
 | |
| 
 | |
|     return s;
 | |
| }
 |