1 #include <QDataStream>
2 #include <QFileInfo>
3 #include <QImageReader>
4 #include "common/tifffile.h"
5 #include "exifparser.h"
6
7
8 #define SOI_MARKER 0xFFD8
9 #define APP1_MARKER 0xFFE1
10
11 #define GPSIFDTag 34853
12 #define ImageDescription 270
13
14 #define GPSLatitudeRef 1
15 #define GPSLatitude 2
16 #define GPSLongitudeRef 3
17 #define GPSLongitude 4
18 #define GPSAltitudeRef 5
19 #define GPSAltitude 6
20 #define GPSTimeStamp 7
21 #define GPSDateStamp 29
22
23
text(TIFFFile & file,const IFDEntry & e) const24 QString EXIFParser::text(TIFFFile &file, const IFDEntry &e) const
25 {
26 if (e.type != TIFF_ASCII || !e.count)
27 return QString();
28
29 if (e.count <= sizeof(e.offset))
30 return QString(QByteArray((const char *)&e.offset, sizeof(e.offset)));
31
32 if (!file.seek(e.offset))
33 return QString();
34
35 QByteArray str(file.read(e.count));
36 if (str.size() < (int)e.count)
37 return QString();
38
39 return QString(str);
40 }
41
time(TIFFFile & file,const IFDEntry & ts) const42 QTime EXIFParser::time(TIFFFile &file, const IFDEntry &ts) const
43 {
44 if (!(ts.type == TIFF_RATIONAL && ts.count == 3))
45 return QTime();
46
47 if (!file.seek(ts.offset))
48 return QTime();
49
50 double hms[3];
51 for (int i = 0; i < 3; i++) {
52 quint32 num, den;
53 if (!file.readValue(num))
54 return QTime();
55 if (!file.readValue(den))
56 return QTime();
57
58 hms[i] = num/(double)den;
59 }
60
61 return QTime((int)hms[0], (int)hms[1], (int)hms[2]);
62 }
63
altitude(TIFFFile & file,const IFDEntry & alt,const IFDEntry & altRef) const64 double EXIFParser::altitude(TIFFFile &file, const IFDEntry &alt,
65 const IFDEntry &altRef) const
66 {
67 if (!(alt.type == TIFF_RATIONAL && alt.count == 1))
68 return NAN;
69
70 if (!file.seek(alt.offset))
71 return NAN;
72
73 quint32 num, den;
74 if (!file.readValue(num))
75 return NAN;
76 if (!file.readValue(den))
77 return NAN;
78
79 return (altRef.type == TIFF_BYTE && altRef.count == 1 && altRef.offset)
80 ? -(num/(double)den) : num/(double)den;
81 }
82
coordinate(TIFFFile & file,const IFDEntry & ll) const83 double EXIFParser::coordinate(TIFFFile &file, const IFDEntry &ll) const
84 {
85 // Some broken image creators like NOKIA phones use a wrong (SRATIONAL)
86 // data type
87 if (!((ll.type == TIFF_RATIONAL || ll.type == TIFF_SRATIONAL)
88 && ll.count == 3))
89 return NAN;
90
91 if (!file.seek(ll.offset))
92 return NAN;
93
94 double dms[3];
95 for (int i = 0; i < 3; i++) {
96 quint32 num, den;
97 if (!file.readValue(num))
98 return NAN;
99 if (!file.readValue(den))
100 return NAN;
101
102 dms[i] = num/(double)den;
103 }
104
105 return dms[0] + dms[1]/60 + dms[2]/3600;
106 }
107
coordinates(TIFFFile & file,const IFDEntry & lon,const IFDEntry & lonRef,const IFDEntry & lat,const IFDEntry & latRef) const108 Coordinates EXIFParser::coordinates(TIFFFile &file, const IFDEntry &lon,
109 const IFDEntry &lonRef, const IFDEntry &lat, const IFDEntry &latRef) const
110 {
111 if (!(latRef.type == TIFF_ASCII && latRef.count == 2
112 && lonRef.type == TIFF_ASCII && lonRef.count == 2))
113 return Coordinates();
114
115 Coordinates c(coordinate(file, lon), coordinate(file, lat));
116 if (!c.isValid())
117 return Coordinates();
118
119 char ew = file.isBE() ? lonRef.offset >> 24 : lonRef.offset;
120 char ns = file.isBE() ? latRef.offset >> 24 : latRef.offset;
121
122 if (ew == 'W')
123 c.rlon() = -c.lon();
124 if (ns == 'S')
125 c.rlat() = -c.lat();
126
127 return c;
128 }
129
readEntry(TIFFFile & file,const QSet<quint16> & tags,QMap<quint16,IFDEntry> & entries) const130 bool EXIFParser::readEntry(TIFFFile &file, const QSet<quint16> &tags,
131 QMap<quint16, IFDEntry> &entries) const
132 {
133 IFDEntry entry;
134 quint16 tag;
135
136 if (!file.readValue(tag))
137 return false;
138 if (!file.readValue(entry.type))
139 return false;
140 if (!file.readValue(entry.count))
141 return false;
142 if (!file.readValue(entry.offset))
143 return false;
144
145 if (tags.contains(tag))
146 entries.insert(tag, entry);
147
148 return true;
149 }
150
readIFD(TIFFFile & file,quint32 offset,const QSet<quint16> & tags,QMap<quint16,IFDEntry> & entries) const151 bool EXIFParser::readIFD(TIFFFile &file, quint32 offset,
152 const QSet<quint16> &tags, QMap<quint16, IFDEntry> &entries) const
153 {
154 quint16 count;
155
156 if (!file.seek(offset))
157 return false;
158 if (!file.readValue(count))
159 return false;
160
161 for (quint16 i = 0; i < count; i++)
162 if (!readEntry(file, tags, entries))
163 return false;
164
165 return true;
166 }
167
parseTIFF(QFile * file,QVector<Waypoint> & waypoints)168 bool EXIFParser::parseTIFF(QFile *file, QVector<Waypoint> &waypoints)
169 {
170 TIFFFile tiff(file);
171 if (!tiff.isValid()) {
172 _errorString = "Invalid EXIF data";
173 return false;
174 }
175
176 QSet<quint16> IFD0Tags;
177 IFD0Tags << GPSIFDTag << ImageDescription;
178 QMap<quint16, IFDEntry> IFD0;
179 for (quint32 ifd = tiff.ifd(); ifd; ) {
180 if (!readIFD(tiff, ifd, IFD0Tags, IFD0) || !tiff.readValue(ifd)) {
181 _errorString = "Invalid IFD0";
182 return false;
183 }
184 }
185 if (!IFD0.contains(GPSIFDTag)) {
186 _errorString = "GPS IFD not found";
187 return false;
188 }
189
190 QSet<quint16> GPSIFDTags;
191 GPSIFDTags << GPSLatitude << GPSLongitude << GPSLatitudeRef
192 << GPSLongitudeRef << GPSAltitude << GPSAltitudeRef << GPSDateStamp
193 << GPSTimeStamp;
194 QMap<quint16, IFDEntry> GPSIFD;
195 for (quint32 ifd = IFD0.value(GPSIFDTag).offset; ifd; ) {
196 if (!readIFD(tiff, ifd, GPSIFDTags, GPSIFD) || !tiff.readValue(ifd)) {
197 _errorString = "Invalid GPS IFD";
198 return false;
199 }
200 }
201
202 Coordinates c(coordinates(tiff, GPSIFD.value(GPSLongitude),
203 GPSIFD.value(GPSLongitudeRef), GPSIFD.value(GPSLatitude),
204 GPSIFD.value(GPSLatitudeRef)));
205 if (!c.isValid()) {
206 _errorString = "Invalid/missing GPS coordinates";
207 return false;
208 }
209
210 file->reset();
211 ImageInfo img(file->fileName(), QImageReader(file).size());
212
213 Waypoint wp(c);
214 wp.setName(QFileInfo(file->fileName()).baseName());
215 wp.addImage(img);
216 wp.setElevation(altitude(tiff, GPSIFD.value(GPSAltitude),
217 GPSIFD.value(GPSAltitudeRef)));
218 wp.setTimestamp(QDateTime(QDate::fromString(text(tiff,
219 GPSIFD.value(GPSDateStamp)), "yyyy:MM:dd"), time(tiff,
220 GPSIFD.value(GPSTimeStamp)), Qt::UTC));
221 wp.setDescription(text(tiff, IFD0.value(ImageDescription)).trimmed());
222
223 waypoints.append(wp);
224
225 return true;
226 }
227
parse(QFile * file,QList<TrackData> & tracks,QList<RouteData> & routes,QList<Area> & polygons,QVector<Waypoint> & waypoints)228 bool EXIFParser::parse(QFile *file, QList<TrackData> &tracks,
229 QList<RouteData> &routes, QList<Area> &polygons,
230 QVector<Waypoint> &waypoints)
231 {
232 Q_UNUSED(tracks);
233 Q_UNUSED(routes);
234 Q_UNUSED(polygons);
235 quint16 marker;
236
237 QDataStream stream(file);
238 stream.setByteOrder(QDataStream::BigEndian);
239 stream >> marker;
240 if (marker != SOI_MARKER) {
241 _errorString = "Not a JPEG file";
242 return false;
243 }
244
245 while (!stream.atEnd()) {
246 stream >> marker;
247 if (marker == APP1_MARKER) {
248 quint16 size;
249 char magic[6];
250 stream >> size;
251 if (stream.readRawData(magic, sizeof(magic)) == sizeof(magic) &&
252 !memcmp(magic, "Exif\0\0", sizeof(magic)))
253 return parseTIFF(file, waypoints);
254 else
255 break;
256 }
257 }
258
259 _errorString = "No EXIF data found";
260 return false;
261 }
262