/*
* Copyright 2002-2016 Drew Noakes
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* More information about this project is available at:
*
* https://drewnoakes.com/code/exif/
* https://github.com/drewnoakes/metadata-extractor
*/
package com.drew.metadata.exif;
import com.drew.lang.GeoLocation;
import com.drew.lang.Rational;
import com.drew.lang.annotations.NotNull;
import com.drew.lang.annotations.Nullable;
import com.drew.metadata.TagDescriptor;
import java.text.DecimalFormat;
import static com.drew.metadata.exif.GpsDirectory.*;
/**
* Provides human-readable string representations of tag values stored in a {@link GpsDirectory}.
*
* @author Drew Noakes https://drewnoakes.com
*/
public class GpsDescriptor extends TagDescriptor<GpsDirectory>
{
public GpsDescriptor(@NotNull GpsDirectory directory)
{
super(directory);
}
@Override
@Nullable
public String getDescription(int tagType)
{
switch (tagType) {
case TAG_VERSION_ID:
return getGpsVersionIdDescription();
case TAG_ALTITUDE:
return getGpsAltitudeDescription();
case TAG_ALTITUDE_REF:
return getGpsAltitudeRefDescription();
case TAG_STATUS:
return getGpsStatusDescription();
case TAG_MEASURE_MODE:
return getGpsMeasureModeDescription();
case TAG_SPEED_REF:
return getGpsSpeedRefDescription();
case TAG_TRACK_REF:
case TAG_IMG_DIRECTION_REF:
case TAG_DEST_BEARING_REF:
return getGpsDirectionReferenceDescription(tagType);
case TAG_TRACK:
case TAG_IMG_DIRECTION:
case TAG_DEST_BEARING:
return getGpsDirectionDescription(tagType);
case TAG_DEST_DISTANCE_REF:
return getGpsDestinationReferenceDescription();
case TAG_TIME_STAMP:
return getGpsTimeStampDescription();
case TAG_LONGITUDE:
// three rational numbers -- displayed in HH"MM"SS.ss
return getGpsLongitudeDescription();
case TAG_LATITUDE:
// three rational numbers -- displayed in HH"MM"SS.ss
return getGpsLatitudeDescription();
case TAG_DIFFERENTIAL:
return getGpsDifferentialDescription();
default:
return super.getDescription(tagType);
}
}
@Nullable
private String getGpsVersionIdDescription()
{
return getVersionBytesDescription(TAG_VERSION_ID, 1);
}
@Nullable
public String getGpsLatitudeDescription()
{
GeoLocation location = _directory.getGeoLocation();
return location == null ? null : GeoLocation.decimalToDegreesMinutesSecondsString(location.getLatitude());
}
@Nullable
public String getGpsLongitudeDescription()
{
GeoLocation location = _directory.getGeoLocation();
return location == null ? null : GeoLocation.decimalToDegreesMinutesSecondsString(location.getLongitude());
}
@Nullable
public String getGpsTimeStampDescription()
{
// time in hour, min, sec
Rational[] timeComponents = _directory.getRationalArray(TAG_TIME_STAMP);
DecimalFormat df = new DecimalFormat("00.000");
return timeComponents == null
? null
: String.format("%02d:%02d:%s UTC",
timeComponents[0].intValue(),
timeComponents[1].intValue(),
df.format(timeComponents[2].doubleValue()));
}
@Nullable
public String getGpsDestinationReferenceDescription()
{
final String value = _directory.getString(TAG_DEST_DISTANCE_REF);
if (value == null)
return null;
String distanceRef = value.trim();
if ("K".equalsIgnoreCase(distanceRef)) {
return "kilometers";
} else if ("M".equalsIgnoreCase(distanceRef)) {
return "miles";
} else if ("N".equalsIgnoreCase(distanceRef)) {
return "knots";
} else {
return "Unknown (" + distanceRef + ")";
}
}
@Nullable
public String getGpsDirectionDescription(int tagType)
{
Rational angle = _directory.getRational(tagType);
// provide a decimal version of rational numbers in the description, to avoid strings like "35334/199 degrees"
String value = angle != null
? new DecimalFormat("0.##").format(angle.doubleValue())
: _directory.getString(tagType);
return value == null || value.trim().length() == 0 ? null : value.trim() + " degrees";
}
@Nullable
public String getGpsDirectionReferenceDescription(int tagType)
{
final String value = _directory.getString(tagType);
if (value == null)
return null;
String gpsDistRef = value.trim();
if ("T".equalsIgnoreCase(gpsDistRef)) {
return "True direction";
} else if ("M".equalsIgnoreCase(gpsDistRef)) {
return "Magnetic direction";
} else {
return "Unknown (" + gpsDistRef + ")";
}
}
@Nullable
public String getGpsSpeedRefDescription()
{
final String value = _directory.getString(TAG_SPEED_REF);
if (value == null)
return null;
String gpsSpeedRef = value.trim();
if ("K".equalsIgnoreCase(gpsSpeedRef)) {
return "kph";
} else if ("M".equalsIgnoreCase(gpsSpeedRef)) {
return "mph";
} else if ("N".equalsIgnoreCase(gpsSpeedRef)) {
return "knots";
} else {
return "Unknown (" + gpsSpeedRef + ")";
}
}
@Nullable
public String getGpsMeasureModeDescription()
{
final String value = _directory.getString(TAG_MEASURE_MODE);
if (value == null)
return null;
String gpsSpeedMeasureMode = value.trim();
if ("2".equalsIgnoreCase(gpsSpeedMeasureMode)) {
return "2-dimensional measurement";
} else if ("3".equalsIgnoreCase(gpsSpeedMeasureMode)) {
return "3-dimensional measurement";
} else {
return "Unknown (" + gpsSpeedMeasureMode + ")";
}
}
@Nullable
public String getGpsStatusDescription()
{
final String value = _directory.getString(TAG_STATUS);
if (value == null)
return null;
String gpsStatus = value.trim();
if ("A".equalsIgnoreCase(gpsStatus)) {
return "Active (Measurement in progress)";
} else if ("V".equalsIgnoreCase(gpsStatus)) {
return "Void (Measurement Interoperability)";
} else {
return "Unknown (" + gpsStatus + ")";
}
}
@Nullable
public String getGpsAltitudeRefDescription()
{
return getIndexedDescription(TAG_ALTITUDE_REF, "Sea level", "Below sea level");
}
@Nullable
public String getGpsAltitudeDescription()
{
final Rational value = _directory.getRational(TAG_ALTITUDE);
return value == null ? null : value.intValue() + " metres";
}
@Nullable
public String getGpsDifferentialDescription()
{
return getIndexedDescription(TAG_DIFFERENTIAL, "No Correction", "Differential Corrected");
}
@Nullable
public String getDegreesMinutesSecondsDescription()
{
GeoLocation location = _directory.getGeoLocation();
return location == null ? null : location.toDMSString();
}
}