Clean ExifInterface. Prepare to make it public. (700beb48) · Commits · e / os / android_frameworks_base

media/java/android/media/ExifInterface.java

+152 −216

Original line number	Diff line number	Diff line
		@@ -16,8 +16,7 @@

		package android.media;

		import android.util.Log;

		import java.io.IOException;
		import java.text.ParsePosition;
		import java.text.SimpleDateFormat;
		import java.util.Date;
		@@ -25,171 +24,103 @@ import java.util.HashMap;
		import java.util.Map;

		/**
		* Wrapper for native Exif library
		* This is a class for reading and writing Exif tags in a JPEG file.
		* {@hide}
		*/
		public class ExifInterface {
		private static final String TAG = "ExifInterface";
		private String mFilename;

		// Constants used for the Orientation Exif tag.
		public static final int ORIENTATION_UNDEFINED = 0;
		public static final int ORIENTATION_NORMAL = 1;

		// Constants used for white balance
		public static final int WHITEBALANCE_AUTO = 0;
		public static final int WHITEBALANCE_MANUAL = 1;

		// left right reversed mirror
		public static final int ORIENTATION_FLIP_HORIZONTAL = 2;
		public static final int ORIENTATION_ROTATE_180 = 3;

		// upside down mirror
		public static final int ORIENTATION_FLIP_VERTICAL = 4;

		// flipped about top-left <--> bottom-right axis
		public static final int ORIENTATION_TRANSPOSE = 5;

		// rotate 90 cw to right it
		public static final int ORIENTATION_ROTATE_90 = 6;

		// flipped about top-right <--> bottom-left axis
		public static final int ORIENTATION_TRANSVERSE = 7;

		// rotate 270 to right it
		public static final int ORIENTATION_ROTATE_270 = 8;

		// The Exif tag names
		public static final String TAG_ORIENTATION = "Orientation";

		public static final String TAG_DATETIME = "DateTime";
		public static final String TAG_MAKE = "Make";
		public static final String TAG_MODEL = "Model";
		public static final String TAG_FLASH = "Flash";
		public static final String TAG_IMAGE_WIDTH = "ImageWidth";
		public static final String TAG_IMAGE_LENGTH = "ImageLength";

		public static final String TAG_GPS_LATITUDE = "GPSLatitude";
		public static final String TAG_GPS_LONGITUDE = "GPSLongitude";

		public static final String TAG_GPS_LATITUDE_REF = "GPSLatitudeRef";
		public static final String TAG_GPS_LONGITUDE_REF = "GPSLongitudeRef";
		public static final String TAG_WHITE_BALANCE = "WhiteBalance";

		private boolean mSavedAttributes = false;
		private boolean mHasThumbnail = false;
		private HashMap<String, String> mCachedAttributes = null;
		// Constants used for the Orientation Exif tag.
		public static final int ORIENTATION_UNDEFINED = 0;
		public static final int ORIENTATION_NORMAL = 1;
		public static final int ORIENTATION_FLIP_HORIZONTAL = 2; // left right reversed mirror
		public static final int ORIENTATION_ROTATE_180 = 3;
		public static final int ORIENTATION_FLIP_VERTICAL = 4; // upside down mirror
		public static final int ORIENTATION_TRANSPOSE = 5; // flipped about top-left <--> bottom-right axis
		public static final int ORIENTATION_ROTATE_90 = 6; // rotate 90 cw to right it
		public static final int ORIENTATION_TRANSVERSE = 7; // flipped about top-right <--> bottom-left axis
		public static final int ORIENTATION_ROTATE_270 = 8; // rotate 270 to right it

		// Constants used for white balance
		public static final int WHITEBALANCE_AUTO = 0;
		public static final int WHITEBALANCE_MANUAL = 1;

		static {
		System.loadLibrary("exif");
		}

		private static ExifInterface sExifObj = null;
		/**
		* Since the underlying jhead native code is not thread-safe,
		* ExifInterface should use singleton interface instead of public
		* constructor.
		*/
		private static synchronized ExifInterface instance() {
		if (sExifObj == null) {
		sExifObj = new ExifInterface();
		}
		private String mFilename;
		private HashMap<String, String> mAttributes;
		private boolean mHasThumbnail = false;

		return sExifObj;
		}
		// Because the underlying implementation (jhead) uses static variables,
		// there can only be one user at a time for the native functions (and
		// they cannot keep state in the native code across function calls). We
		// use sLock the serialize the accesses.
		private static Object sLock = new Object();

		/**
		* The following 3 static methods are handy routines for atomic operation
		* of underlying jhead library. It retrieves EXIF data and then release
		* ExifInterface immediately.
		* Reads Exif tags from the specified JPEG file.
		*/
		public static synchronized HashMap<String, String> loadExifData(String filename) {
		ExifInterface exif = instance();
		HashMap<String, String> exifData = null;
		if (exif != null) {
		exif.setFilename(filename);
		exifData = exif.getAttributes();
		}
		return exifData;
		}

		public static synchronized void saveExifData(String filename, HashMap<String, String> exifData) {
		ExifInterface exif = instance();
		if (exif != null) {
		exif.setFilename(filename);
		exif.saveAttributes(exifData);
		}
		}

		public static synchronized byte[] getExifThumbnail(String filename) {
		ExifInterface exif = instance();
		if (exif != null) {
		exif.setFilename(filename);
		return exif.getThumbnail();
		}
		return null;
		}

		public void setFilename(String filename) {
		if (mFilename == null \|\| !mFilename.equals(filename)) {
		public ExifInterface(String filename) throws IOException {
		mFilename = filename;
		mCachedAttributes = null;
		}
		loadAttributes();
		}

		/**
		* Given a HashMap of Exif tags and associated values, an Exif section in
		* the JPG file is created and loaded with the tag data. saveAttributes()
		* is expensive because it involves copying all the JPG data from one file
		* to another and deleting the old file and renaming the other. It's best
		* to collect all the attributes to write and make a single call rather
		* than multiple calls for each attribute. You must call "commitChanges()"
		* at some point to commit the changes.
		* Returns the value of the specified tag or {@code null} if there
		* is no such tag in the file.
		*
		* @param tag the name of the tag.
		*/
		public void saveAttributes(HashMap<String, String> attributes) {
		// format of string passed to native C code:
		// "attrCnt attr1=valueLen value1attr2=value2Len value2..."
		// example:
		// "4 attrPtr ImageLength=4 1024Model=6 FooImageWidth=4 1280Make=3 FOO"
		StringBuilder sb = new StringBuilder();
		int size = attributes.size();
		if (attributes.containsKey("hasThumbnail")) {
		--size;
		}
		sb.append(size + " ");
		for (Map.Entry<String, String> iter : attributes.entrySet()) {
		String key = iter.getKey();
		if (key.equals("hasThumbnail")) {
		// this is a fake attribute not saved as an exif tag
		continue;
		}
		String val = iter.getValue();
		sb.append(key + "=");
		sb.append(val.length() + " ");
		sb.append(val);
		}
		String s = sb.toString();
		saveAttributesNative(mFilename, s);
		commitChangesNative(mFilename);
		mSavedAttributes = true;
		public String getAttribute(String tag) {
		return mAttributes.get(tag);
		}

		/**
		* Returns a HashMap loaded with the Exif attributes of the file. The key
		* is the standard tag name and the value is the tag's value: e.g.
		* Model -> Nikon. Numeric values are returned as strings.
		* Set the value of the specified tag.
		*
		* @param tag the name of the tag.
		* @param value the value of the tag.
		*/
		public HashMap<String, String> getAttributes() {
		if (mCachedAttributes != null) {
		return mCachedAttributes;
		public void setAttribute(String tag, String value) {
		mAttributes.put(tag, value);
		}

		/**
		* Initialize mAttributes with the attributes from the file mFilename.
		*
		* mAttributes is a HashMap which stores the Exif attributes of the file.
		* The key is the standard tag name and the value is the tag's value: e.g.
		* Model -> Nikon. Numeric values are stored as strings.
		*
		* This function also initialize mHasThumbnail to indicate whether the
		* file has a thumbnail inside.
		*/
		private void loadAttributes() {
		// format of string passed from native C code:
		// "attrCnt attr1=valueLen value1attr2=value2Len value2..."
		// example:
		// "4 attrPtr ImageLength=4 1024Model=6 FooImageWidth=4 1280Make=3 FOO"
		mCachedAttributes = new HashMap<String, String>();
		mAttributes = new HashMap<String, String>();

		String attrStr = getAttributesNative(mFilename);
		String attrStr;
		synchronized (sLock) {
		attrStr = getAttributesNative(mFilename);
		}

		// get count
		int ptr = attrStr.indexOf(' ');
		@@ -215,17 +146,78 @@ public class ExifInterface {
		if (attrName.equals("hasThumbnail")) {
		mHasThumbnail = attrValue.equalsIgnoreCase("true");
		} else {
		mCachedAttributes.put(attrName, attrValue);
		mAttributes.put(attrName, attrValue);
		}
		}
		return mCachedAttributes;
		}

		/**
		* Given a numerical white balance value, return a
		* human-readable string describing it.
		* Save the tag data into the JPEG file. This is expensive because it involves
		* copying all the JPG data from one file to another and deleting the old file
		* and renaming the other. It's best to use {@link setAttribute()} to set all
		* attributes to write and make a single call rather than multiple calls for
		* each attribute.
		*/
		public static String whiteBalanceToString(int whitebalance) {
		public void saveAttributes() throws IOException {
		// format of string passed to native C code:
		// "attrCnt attr1=valueLen value1attr2=value2Len value2..."
		// example:
		// "4 attrPtr ImageLength=4 1024Model=6 FooImageWidth=4 1280Make=3 FOO"
		StringBuilder sb = new StringBuilder();
		int size = mAttributes.size();
		if (mAttributes.containsKey("hasThumbnail")) {
		--size;
		}
		sb.append(size + " ");
		for (Map.Entry<String, String> iter : mAttributes.entrySet()) {
		String key = iter.getKey();
		if (key.equals("hasThumbnail")) {
		// this is a fake attribute not saved as an exif tag
		continue;
		}
		String val = iter.getValue();
		sb.append(key + "=");
		sb.append(val.length() + " ");
		sb.append(val);
		}
		String s = sb.toString();
		synchronized (sLock) {
		saveAttributesNative(mFilename, s);
		commitChangesNative(mFilename);
		}
		}

		/**
		* Returns true if the JPEG file has a thumbnail.
		*/
		public boolean hasThumbnail() {
		return mHasThumbnail;
		}

		/**
		* Returns the thumbnail inside the JPEG file, or {@code null} if there is no thumbnail.
		*/
		public byte[] getThumbnail() {
		synchronized (sLock) {
		return getThumbnailNative(mFilename);
		}
		}

		/**
		* Returns a human-readable string describing the white balance value. Returns empty
		* string if there is no white balance value or it is not recognized.
		*/
		public String getWhiteBalanceString() {
		String value = getAttribute(TAG_WHITE_BALANCE);
		if (value == null) return "";

		int whitebalance;
		try {
		whitebalance = Integer.parseInt(value);
		} catch (NumberFormatException ex) {
		return "";
		}

		switch (whitebalance) {
		case WHITEBALANCE_AUTO:
		return "Auto";
		@@ -237,12 +229,21 @@ public class ExifInterface {
		}

		/**
		* Given a numerical orientation, return a human-readable string describing
		* the orientation.
		* Returns a human-readable string describing the orientation value. Returns empty
		* string if there is no orientation value or it it not recognized.
		*/
		public static String orientationToString(int orientation) {
		// TODO: this function needs to be localized and use string resource ids
		// rather than strings
		public String getOrientationString() {
		// TODO: this function needs to be localized.
		String value = getAttribute(TAG_ORIENTATION);
		if (value == null) return "";

		int orientation;
		try {
		orientation = Integer.parseInt(value);
		} catch (NumberFormatException ex) {
		return "";
		}

		String orientationString;
		switch (orientation) {
		case ORIENTATION_NORMAL:
		@@ -277,48 +278,21 @@ public class ExifInterface {
		}

		/**
		* Copies the thumbnail data out of the filename and puts it in the Exif
		* data associated with the file used to create this object. You must call
		* "commitChanges()" at some point to commit the changes.
		* Returns the latitude and longitude value in a float array. The first element is
		* the latitude, and the second element is the longitude.
		*/
		public boolean appendThumbnail(String thumbnailFileName) {
		if (!mSavedAttributes) {
		throw new RuntimeException("Must call saveAttributes "
		+ "before calling appendThumbnail");
		}
		mHasThumbnail = appendThumbnailNative(mFilename, thumbnailFileName);
		return mHasThumbnail;
		}

		public boolean hasThumbnail() {
		if (!mSavedAttributes) {
		getAttributes();
		}
		return mHasThumbnail;
		}

		public byte[] getThumbnail() {
		return getThumbnailNative(mFilename);
		}

		public static float[] getLatLng(HashMap<String, String> exifData) {
		if (exifData == null) {
		return null;
		}

		String latValue = exifData.get(ExifInterface.TAG_GPS_LATITUDE);
		String latRef = exifData.get(ExifInterface.TAG_GPS_LATITUDE_REF);
		String lngValue = exifData.get(ExifInterface.TAG_GPS_LONGITUDE);
		String lngRef = exifData.get(ExifInterface.TAG_GPS_LONGITUDE_REF);
		public float[] getLatLong() {
		String latValue = mAttributes.get(ExifInterface.TAG_GPS_LATITUDE);
		String latRef = mAttributes.get(ExifInterface.TAG_GPS_LATITUDE_REF);
		String lngValue = mAttributes.get(ExifInterface.TAG_GPS_LONGITUDE);
		String lngRef = mAttributes.get(ExifInterface.TAG_GPS_LONGITUDE_REF);
		float[] latlng = null;

		if (latValue != null && latRef != null
		&& lngValue != null && lngRef != null) {
		latlng = new float[2];
		latlng[0] = ExifInterface.convertRationalLatLonToFloat(
		latValue, latRef);
		latlng[1] = ExifInterface.convertRationalLatLonToFloat(
		lngValue, lngRef);
		latlng[0] = convertRationalLatLonToFloat(latValue, latRef);
		latlng[1] = convertRationalLatLonToFloat(lngValue, lngRef);
		}

		return latlng;
		@@ -327,14 +301,12 @@ public class ExifInterface {
		private static SimpleDateFormat sFormatter =
		new SimpleDateFormat("yyyy:MM:dd HH:mm:ss");

		// Returns number of milliseconds since Jan. 1, 1970, midnight GMT.
		// Returns -1 if the date time information if not available.
		public static long getDateTime(HashMap<String, String> exifData) {
		if (exifData == null) {
		return -1;
		}

		String dateTimeString = exifData.get(ExifInterface.TAG_DATETIME);
		/**
		* Returns number of milliseconds since Jan. 1, 1970, midnight GMT.
		* Returns -1 if the date time information if not available.
		*/
		public long getDateTime() {
		String dateTimeString = mAttributes.get(TAG_DATETIME);
		if (dateTimeString == null) return -1;

		ParsePosition pos = new ParsePosition(0);
		@@ -347,7 +319,7 @@ public class ExifInterface {
		}
		}

		public static float convertRationalLatLonToFloat(
		private static float convertRationalLatLonToFloat(
		String rationalString, String ref) {
		try {
		String [] parts = rationalString.split(",");
		@@ -377,42 +349,6 @@ public class ExifInterface {
		}
		}

		public static String convertRationalLatLonToDecimalString(
		String rationalString, String ref, boolean usePositiveNegative) {
		float result = convertRationalLatLonToFloat(rationalString, ref);

		String preliminaryResult = String.valueOf(result);
		if (usePositiveNegative) {
		String neg = (ref.equals("S") \|\| ref.equals("E")) ? "-" : "";
		return neg + preliminaryResult;
		} else {
		return preliminaryResult + String.valueOf((char) 186) + " "
		+ ref;
		}
		}

		public static String makeLatLongString(double d) {
		d = Math.abs(d);

		int degrees = (int) d;

		double remainder = d - degrees;
		int minutes = (int) (remainder * 60D);
		// really seconds * 1000
		int seconds = (int) (((remainder * 60D) - minutes) * 60D * 1000D);

		String retVal = degrees + "/1," + minutes + "/1," + seconds + "/1000";
		return retVal;
		}

		public static String makeLatStringRef(double lat) {
		return lat >= 0D ? "N" : "S";
		}

		public static String makeLonStringRef(double lon) {
		return lon >= 0D ? "W" : "E";
		}

		private native boolean appendThumbnailNative(String fileName,
		String thumbnailFileName);

media/java/android/media/MediaScanner.java

+9 −5

Original line number	Diff line number	Diff line
		@@ -719,16 +719,20 @@ public class MediaScanner
		values.put(Audio.Media.IS_MUSIC, music);
		values.put(Audio.Media.IS_PODCAST, podcasts);
		} else if (mFileType == MediaFile.FILE_TYPE_JPEG) {
		HashMap<String, String> exifData =
		ExifInterface.loadExifData(entry.mPath);
		if (exifData != null) {
		float[] latlng = ExifInterface.getLatLng(exifData);
		ExifInterface exif = null;
		try {
		exif = new ExifInterface(entry.mPath);
		} catch (IOException ex) {
		// exif is null
		}
		if (exif != null) {
		float[] latlng = exif.getLatLong();
		if (latlng != null) {
		values.put(Images.Media.LATITUDE, latlng[0]);
		values.put(Images.Media.LONGITUDE, latlng[1]);
		}

		long time = ExifInterface.getDateTime(exifData);
		long time = exif.getDateTime();
		if (time != -1) {
		values.put(Images.Media.DATE_TAKEN, time);
		}