--- /dev/null
+/*
+
+ Support for embedded Exif-GPS information.
+
+ Copyright (C) 2008 Olaf Klein, o.b.klein@gpsbabel.org
+
+ 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
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ 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
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111 USA
+
+ */
+
+#include "defs.h"
+#include "config.h"
+#include "garmin_tables.h"
+#include "jeeps/gpsmath.h"
+#include "strptime.h"
+#include <ctype.h>
+
+#define MYNAME "exif"
+
+typedef struct exif_tag_s {
+ gbuint16 tag;
+ gbuint16 type;
+ gbint32 count;
+ gbuint32 offs;
+} exif_tag_t;
+
+static gbfile *fin;
+static gbsize_t exif_ifd, gps_ifd;
+static char byte_order;
+static waypoint *wpt;
+static gbsize_t fileoffs;
+static char *opt_filename;
+static time_t timestamp;
+
+static
+arglist_t exif_args[] = {
+ {"filename", &opt_filename, "Set waypoint name to source filename.", "Y", ARGTYPE_BOOL, ARG_NOMINMAX},
+ ARG_TERMINATOR
+};
+
+#define EXIF_IFD -1
+#define GPS_IFD -2
+
+/*******************************************************************************
+* %%% global callbacks called by gpsbabel main process %%% *
+*******************************************************************************/
+
+static void
+exif_rd_init(const char *fname)
+{
+ fin = gbfopen_le(fname, "rb", MYNAME);
+}
+
+static void
+exif_rd_deinit(void)
+{
+ gbfclose(fin);
+}
+
+static int
+exif_tag_size(const exif_tag_t *tag)
+{
+ int size;
+
+ switch(tag->type) {
+ case 1:
+ case 2:
+ case 7: size = 1; break;
+ case 3: size = 2; break;
+ case 4:
+ case 9: size = 4; break;
+ case 5:
+ case 10: size = 8; break;
+ default:
+ return 0;
+ }
+ return size * tag->count;
+}
+
+static double
+exif_read_double(const gbsize_t offs)
+{
+ unsigned int num, den;
+
+ if (offs) gbfseek(fin, fileoffs + offs, SEEK_SET);
+
+ num = gbfgetuint32(fin);
+ den = gbfgetuint32(fin);
+ if (den == 0) den = 1;
+
+ return (double)num / den;
+}
+
+static double
+exif_read_coord(const exif_tag_t *tag)
+{
+ double deg, min, sec;
+
+ deg = exif_read_double(tag->offs);
+ if (tag->count == 1) return deg;
+
+ min = exif_read_double(0);
+ deg += (min / 60);
+ if (tag->count == 2) return deg;
+
+ sec = exif_read_double(0);
+ deg += (sec / 3600);
+
+ return deg;
+}
+
+static char *
+exif_read_string(const exif_tag_t *tag)
+{
+ if (tag->count > 4) {
+ gbfseek(fin, fileoffs + tag->offs, SEEK_SET);
+ return gbfgetcstr(fin);
+ }
+ else {
+ char buff[4];
+#ifdef WORDS_BIGENDIAN
+ be_write32(buff, tag->offs);
+#else
+ le_write32(buff, tag->offs);
+#endif
+ return xstrdup(buff);
+ }
+}
+
+static time_t
+exif_read_timestamp(const exif_tag_t *tag)
+{
+ double hour, min, sec;
+
+ hour = exif_read_double(tag->offs);
+ min = exif_read_double(0);
+ sec = exif_read_double(0);
+
+ return ((int)hour * SECONDS_PER_HOUR) + ((int)min * 60) + (int)sec;
+}
+
+static int
+exif_sort_tags_cb(const void *a, const void *b)
+{
+ const exif_tag_t *ea = a;
+ const exif_tag_t *eb = b;
+ return (int)ea->offs - (int)eb->offs;
+}
+
+static gbsize_t
+exif_read_tags(const int ifd)
+{
+ int entries;
+ exif_tag_t *tags;
+ gbsize_t next_ifd = 0;
+ double gpsdop = unknown_alt;
+ char speed_ref = 'K';
+ char lat_ref = '*';
+ char lon_ref = '*';
+ char mode = 'N';
+ int datum = DATUM_WGS84;
+
+ entries = gbfgetint16(fin);
+ if (entries > 0) {
+ int i;
+ tags = xmalloc(entries * sizeof(*tags));
+ for (i = 0; i < entries; i++) {
+ tags[i].tag = gbfgetuint16(fin);
+ tags[i].type = gbfgetuint16(fin);
+ tags[i].count = gbfgetint32(fin);
+ tags[i].offs = gbfgetuint32(fin);
+ }
+ }
+
+ next_ifd = gbfgetuint32(fin);
+
+ if (entries > 0) {
+ int i;
+ char *str, *c;
+ struct tm tm;
+
+ if (entries > 1) /* avoid backward seek */
+ qsort(tags, entries, sizeof(*tags), exif_sort_tags_cb);
+
+ for (i = 0; i < entries; i++) {
+ exif_tag_t *tag = &tags[i];
+ int size = exif_tag_size(tag);
+
+ switch(ifd) {
+ case 0:
+ switch(tag->tag) {
+ case 0x8769:
+ exif_ifd = tag->offs;
+ break;
+ case 0x8825:
+ gps_ifd = tag->offs;
+ break;
+ }
+ break;
+ case 1: /* IFD1 */
+ break;
+ case -1: /* Exif */
+ switch(tag->tag) {
+
+ case 0x9003: /* DateTimeOriginal */
+ str = exif_read_string(tag);
+ c = strptime(str, "%Y:%m:%d %H:%M:%S", &tm);
+ if (c && (*c == '\0'))
+ wpt->creation_time = mklocaltime(&tm);
+ xfree(str);
+ break;
+ }
+ break;
+ case -2: /* GPS */
+ switch(tag->tag) {
+
+ case 0x0001: /* GPSLatitudeRef */
+ lat_ref = tag->offs & 127;
+ break;
+
+ case 0x0002: /* GPSLatitude */
+ wpt->latitude = exif_read_coord(tag);
+ break;
+
+ case 0x0003: /* GPSLongitude */
+ lon_ref = tag->offs & 127;
+ break;
+
+ case 0x0004: /* GPSLongitude */
+ wpt->longitude = exif_read_coord(tag);
+ break;
+
+ case 0x0005: /* GPSAltitudeRef */
+ break;
+
+ case 0x0006: /* GPSAltitude */
+ wpt->altitude = exif_read_double(tag->offs);
+ break;
+
+ case 0x0007: /* GPSTimeStamp */
+ timestamp = exif_read_timestamp(tag);
+ break;
+
+ case 0x0008: /* GPSSatellites */
+ str = exif_read_string(tag);
+ wpt->sat = atoi(str);
+ xfree(str);
+ break;
+
+ case 0x000a: /* GPSMeasureMode */
+ mode = tag->offs & 127;
+ break;
+
+ case 0x000b: /* GPSDOP */
+ gpsdop = exif_read_double(tag->offs);
+ break;
+
+ case 0x000c: /* GPSSpeedRef */
+ speed_ref = tag->offs & 127;
+ break;
+
+ case 0x000d: /* GPSSpeed */
+ WAYPT_SET(wpt, speed, exif_read_double(tag->offs));
+ break;
+
+ case 0x0012: /* GPSMapDatum */
+ str = exif_read_string(tag);
+ datum = gt_lookup_datum_index(str, MYNAME);
+ if (datum < 0)
+ fatal(MYNAME ": Unknown GPSMapDatum \"%s\"!\n", str);
+ xfree(str);
+ break;
+ }
+ break;
+ }
+ }
+ xfree(tags);
+ }
+
+ if (ifd == GPS_IFD) {
+
+ /* Did we get our minimum data ? */
+ if ((wpt->latitude == unknown_alt) || (wpt->longitude == unknown_alt)) {
+ warning(MYNAME ": GPSLatitude and/or GPSLongitude not set!\n");
+ waypt_free(wpt);
+ return 0;
+ }
+
+ if WAYPT_HAS(wpt, speed) {
+ switch(speed_ref) {
+ case 'K':
+ wpt->speed = KPH_TO_MPS(wpt->speed);
+ break;
+ case 'M':
+ wpt->speed = MPH_TO_MPS(wpt->speed);
+ break;
+ case 'N':
+ wpt->speed = KNOTS_TO_MPS(wpt->speed);
+ break;
+ default:
+ wpt->speed = 0;
+ WAYPT_UNSET(wpt, speed);
+ warning(MYNAME ": Unknown GPSSpeedRef unit %c (0x%02x)!\n", speed_ref, speed_ref);
+ }
+ }
+
+ if (lat_ref == 'S') wpt->latitude *= -1;
+ else
+ if (lon_ref == 'W') wpt->longitude *= -1;
+ else if (lon_ref != 'E') warning(MYNAME ": GPSLongitudeRef not set! Using E(east).\n");
+
+ if (datum != DATUM_WGS84) {
+ double alt;
+ GPS_Math_WGS84_To_Known_Datum_M(wpt->latitude, wpt->longitude, 0.0,
+ &wpt->latitude, &wpt->longitude, &alt, datum);
+ }
+
+ if (mode == '2') {
+ wpt->fix = fix_2d;
+ if (gpsdop != unknown_alt) wpt->hdop = gpsdop;
+ }
+ else if (mode == '3') {
+ wpt->fix = fix_3d;
+ if (gpsdop != unknown_alt) wpt->pdop = gpsdop;
+ }
+ }
+
+ return next_ifd;
+}
+
+static void
+exif_read(void)
+{
+ gbint32 code = 0;
+
+ fileoffs = 0;
+ wpt = NULL;
+
+ while (!gbfeof(fin)) {
+
+ unsigned char c = (unsigned)gbfgetc(fin);
+
+ code = (code << 8) | c;
+ if (code == 0x45786966) { /* Look for "Exif" */
+
+ gbsize_t next_ifd;
+ gbint32 ifd;
+
+ int order = gbfgetint32(fin);
+ switch(order) {
+ case 0x49490000: /* "II" - Intel */
+ byte_order = 'I';
+ break;
+ case 0x4D4D0000: /* "MM" - Motorola */
+ byte_order = 'M';
+ break;
+
+ default:
+ continue;
+ }
+ fin->big_endian = (byte_order == 'M');
+ if (gbfgetint16(fin) != 0x002a) continue;
+
+ fileoffs = gbftell(fin) - 4;
+
+ next_ifd = gbfgetuint32(fin);
+ if (! next_ifd) continue; /* No IFD0 ? */
+
+ ifd = gps_ifd = exif_ifd = 0;
+ timestamp = (SECONDS_PER_DAY * 99);
+
+ /* we need the wpt not only during GPS IFD */
+ wpt = waypt_new();
+ wpt->latitude = unknown_alt;
+ wpt->longitude = unknown_alt;
+
+ while (next_ifd) {
+ gbfseek(fin, fileoffs + next_ifd, SEEK_SET);
+ next_ifd = exif_read_tags(ifd++);
+ }
+ if (exif_ifd) {
+ gbfseek(fin, fileoffs + exif_ifd, SEEK_SET);
+ (void) exif_read_tags(EXIF_IFD);
+ }
+ if (gps_ifd) {
+ gbfseek(fin, fileoffs + gps_ifd, SEEK_SET);
+ (void) exif_read_tags(GPS_IFD);
+ }
+ else {
+ warning(MYNAME ": No Exif-GPS information in file \"%s\"!\n", fin->name);
+ waypt_free(wpt);
+ wpt = NULL;
+ }
+
+ if (! wpt) continue;
+
+#if 0
+ if (timestamp != (SECONDS_PER_DAY * 99)) {
+ // wpt->creation_time = timestamp;
+ }
+#endif
+ if (opt_filename) {
+ char *c, *cx;
+ char *str = xstrdup(fin->name);
+
+ cx = str;
+ if ((c = strrchr(cx, ':'))) cx = c + 1;
+ if ((c = strrchr(cx, '\\'))) cx = c + 1;
+ if ((c = strrchr(cx, '/'))) cx = c + 1;
+ if (((c = strchr(cx, '.'))) && (c != cx)) *c = '\0';
+
+ if (wpt->shortname) xfree(wpt->shortname);
+ wpt->shortname = xstrdup(cx);
+ xfree(str);
+ }
+ waypt_add(wpt);
+ return;
+ }
+ }
+ warning(MYNAME ": No Exif header in file \"%s\"!\n", fin->name);
+}
+
+#if 0
+static void
+exif_wr_init(const char *fname)
+{
+ fout = gbfopen(fname, "w", MYNAME);
+}
+
+static void
+exif_wr_deinit(void)
+{
+ gbfclose(fout);
+}
+
+static void
+exif_write(void)
+{
+}
+#endif
+
+/**************************************************************************/
+
+ff_vecs_t exif_vecs = {
+ ff_type_file,
+ {
+ ff_cap_read /* waypoints */,
+ ff_cap_none /* tracks */,
+ ff_cap_none /* routes */
+ },
+ exif_rd_init,
+ NULL, /* exif_wr_init, */
+ exif_rd_deinit,
+ NULL, /* exif_wr_deinit, */
+ exif_read,
+ NULL, /* exif_write */
+ NULL,
+ exif_args,
+ CET_CHARSET_ASCII, 0
+};
+/**************************************************************************/
projects / gpsbabel.git / commitdiff