media/java/android/media/ExifInterface.java - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 2007 The Android Open Source Project
  *
  * 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.
  */

 package android.media;

 import java.io.IOException;
 import java.text.ParsePosition;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.TimeZone;

 /**
  * This is a class for reading and writing Exif tags in a JPEG file.
  */
 public class ExifInterface {

     // 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_GPS_TIMESTAMP = "GPSTimeStamp";
     public static final String TAG_GPS_DATESTAMP = "GPSDateStamp";
     public static final String TAG_WHITE_BALANCE = "WhiteBalance";

     // 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;
     private static SimpleDateFormat sFormatter;

     static {
         System.loadLibrary("exif");
         sFormatter = new SimpleDateFormat("yyyy:MM:dd HH:mm:ss");
         sFormatter.setTimeZone(TimeZone.getTimeZone("UTC"));
     }

     private String mFilename;
     private HashMap<String, String> mAttributes;
     private boolean mHasThumbnail;

     // 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 to serialize the accesses.
     private static Object sLock = new Object();

     /**
      * Reads Exif tags from the specified JPEG file.
      */
     public ExifInterface(String filename) throws IOException {
         mFilename = filename;
         loadAttributes();
     }

     /**
      * Returns the value of the specified tag or {@code null} if there
      * is no such tag in the JPEG file.
      *
      * @param tag the name of the tag.
      */
     public String getAttribute(String tag) {
         return mAttributes.get(tag);
     }

     /**
      * Returns the integer value of the specified tag. If there is no such tag
      * in the JPEG file or the value cannot be parsed as integer, return
      * <var>defaultValue</var>.
      *
      * @param tag the name of the tag.
      * @param defaultValue the value to return if the tag is not available.
      */
     public int getAttributeInt(String tag, int defaultValue) {
         String value = mAttributes.get(tag);
         if (value == null) return defaultValue;
         try {
             return Integer.valueOf(value);
         } catch (NumberFormatException ex) {
             return defaultValue;
         }
     }

     /**
      * Set the value of the specified tag.
      *
      * @param tag the name of the tag.
      * @param value the value of the tag.
      */
     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() throws IOException {
         // 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"
         mAttributes = new HashMap<String, String>();

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

         // get count
         int ptr = attrStr.indexOf(' ');
         int count = Integer.parseInt(attrStr.substring(0, ptr));
         // skip past the space between item count and the rest of the attributes
         ++ptr;

         for (int i = 0; i < count; i++) {
             // extract the attribute name
             int equalPos = attrStr.indexOf('=', ptr);
             String attrName = attrStr.substring(ptr, equalPos);
             ptr = equalPos + 1;     // skip past =

             // extract the attribute value length
             int lenPos = attrStr.indexOf(' ', ptr);
             int attrLen = Integer.parseInt(attrStr.substring(ptr, lenPos));
             ptr = lenPos + 1;       // skip pas the space

             // extract the attribute value
             String attrValue = attrStr.substring(ptr, ptr + attrLen);
             ptr += attrLen;

             if (attrName.equals("hasThumbnail")) {
                 mHasThumbnail = attrValue.equalsIgnoreCase("true");
             } else {
                 mAttributes.put(attrName, attrValue);
             }
         }
     }

     /**
      * 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(String,String)}
      * to set all attributes to write and make a single call rather than multiple
      * calls for each attribute.
      */
     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.
      * The returned data is in JPEG format and can be decoded using
      * {@link android.graphics.BitmapFactory#decodeByteArray(byte[],int,int)}
      */
     public byte[] getThumbnail() {
         synchronized (sLock) {
             return getThumbnailNative(mFilename);
         }
     }

     /**
      * Stores the latitude and longitude value in a float array. The first element is
      * the latitude, and the second element is the longitude. Returns false if the
      * Exif tags are not available.
      */
     public boolean getLatLong(float output[]) {
         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);

         if (latValue != null && latRef != null && lngValue != null && lngRef != null) {
             output[0] = convertRationalLatLonToFloat(latValue, latRef);
             output[1] = convertRationalLatLonToFloat(lngValue, lngRef);
             return true;
         } else {
             return false;
         }
     }

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

         ParsePosition pos = new ParsePosition(0);
         try {
             Date datetime = sFormatter.parse(dateTimeString, pos);
             if (datetime == null) return -1;
             return datetime.getTime();
         } catch (IllegalArgumentException ex) {
             return -1;
         }
     }

     /**
      * Returns number of milliseconds since Jan. 1, 1970, midnight UTC.
      * Returns -1 if the date time information if not available.
      * @hide
      */
     public long getGpsDateTime() {
         String date = mAttributes.get(TAG_GPS_DATESTAMP);
         String time = mAttributes.get(TAG_GPS_TIMESTAMP);
         if (date == null || time == null) return -1;

         String dateTimeString = date + ' ' + time;
         if (dateTimeString == null) return -1;

         ParsePosition pos = new ParsePosition(0);
         try {
             Date datetime = sFormatter.parse(dateTimeString, pos);
             if (datetime == null) return -1;
             return datetime.getTime();
         } catch (IllegalArgumentException ex) {
             return -1;
         }
     }

     private static float convertRationalLatLonToFloat(
             String rationalString, String ref) {
         try {
             String [] parts = rationalString.split(",");

             String [] pair;
             pair = parts[0].split("/");
             int degrees = (int) (Float.parseFloat(pair[0].trim())
                     / Float.parseFloat(pair[1].trim()));

             pair = parts[1].split("/");
             int minutes = (int) ((Float.parseFloat(pair[0].trim())
                     / Float.parseFloat(pair[1].trim())));

             pair = parts[2].split("/");
             float seconds = Float.parseFloat(pair[0].trim())
                     / Float.parseFloat(pair[1].trim());

             float result = degrees + (minutes / 60F) + (seconds / (60F * 60F));
             if ((ref.equals("S") || ref.equals("W"))) {
                 return -result;
             }
             return result;
         } catch (RuntimeException ex) {
             // if for whatever reason we can't parse the lat long then return
             // null
             return 0f;
         }
     }

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

     private native void saveAttributesNative(String fileName,
             String compressedAttributes);

     private native String getAttributesNative(String fileName);

     private native void commitChangesNative(String fileName);

     private native byte[] getThumbnailNative(String fileName);
 }
	/*
	* Copyright (C) 2007 The Android Open Source Project
	*
	* 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.
	*/

	package android.media;

	import java.io.IOException;
	import java.text.ParsePosition;
	import java.text.SimpleDateFormat;
	import java.util.Date;
	import java.util.HashMap;
	import java.util.Map;
	import java.util.TimeZone;

	/**
	* This is a class for reading and writing Exif tags in a JPEG file.
	*/
	public class ExifInterface {

	// 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_GPS_TIMESTAMP = "GPSTimeStamp";
	public static final String TAG_GPS_DATESTAMP = "GPSDateStamp";
	public static final String TAG_WHITE_BALANCE = "WhiteBalance";

	// 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;
	private static SimpleDateFormat sFormatter;

	static {
	System.loadLibrary("exif");
	sFormatter = new SimpleDateFormat("yyyy:MM:dd HH:mm:ss");
	sFormatter.setTimeZone(TimeZone.getTimeZone("UTC"));
	}

	private String mFilename;
	private HashMap<String, String> mAttributes;
	private boolean mHasThumbnail;

	// 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 to serialize the accesses.
	private static Object sLock = new Object();

	/**
	* Reads Exif tags from the specified JPEG file.
	*/
	public ExifInterface(String filename) throws IOException {
	mFilename = filename;
	loadAttributes();
	}

	/**
	* Returns the value of the specified tag or {@code null} if there
	* is no such tag in the JPEG file.
	*
	* @param tag the name of the tag.
	*/
	public String getAttribute(String tag) {
	return mAttributes.get(tag);
	}

	/**
	* Returns the integer value of the specified tag. If there is no such tag
	* in the JPEG file or the value cannot be parsed as integer, return
	* <var>defaultValue</var>.
	*
	* @param tag the name of the tag.
	* @param defaultValue the value to return if the tag is not available.
	*/
	public int getAttributeInt(String tag, int defaultValue) {
	String value = mAttributes.get(tag);
	if (value == null) return defaultValue;
	try {
	return Integer.valueOf(value);
	} catch (NumberFormatException ex) {
	return defaultValue;
	}
	}

	/**
	* Set the value of the specified tag.
	*
	* @param tag the name of the tag.
	* @param value the value of the tag.
	*/
	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() throws IOException {
	// 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"
	mAttributes = new HashMap<String, String>();

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

	// get count
	int ptr = attrStr.indexOf(' ');
	int count = Integer.parseInt(attrStr.substring(0, ptr));
	// skip past the space between item count and the rest of the attributes
	++ptr;

	for (int i = 0; i < count; i++) {
	// extract the attribute name
	int equalPos = attrStr.indexOf('=', ptr);
	String attrName = attrStr.substring(ptr, equalPos);
	ptr = equalPos + 1; // skip past =

	// extract the attribute value length
	int lenPos = attrStr.indexOf(' ', ptr);
	int attrLen = Integer.parseInt(attrStr.substring(ptr, lenPos));
	ptr = lenPos + 1; // skip pas the space

	// extract the attribute value
	String attrValue = attrStr.substring(ptr, ptr + attrLen);
	ptr += attrLen;

	if (attrName.equals("hasThumbnail")) {
	mHasThumbnail = attrValue.equalsIgnoreCase("true");
	} else {
	mAttributes.put(attrName, attrValue);
	}
	}
	}

	/**
	* 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(String,String)}
	* to set all attributes to write and make a single call rather than multiple
	* calls for each attribute.
	*/
	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.
	* The returned data is in JPEG format and can be decoded using
	* {@link android.graphics.BitmapFactory#decodeByteArray(byte[],int,int)}
	*/
	public byte[] getThumbnail() {
	synchronized (sLock) {
	return getThumbnailNative(mFilename);
	}
	}

	/**
	* Stores the latitude and longitude value in a float array. The first element is
	* the latitude, and the second element is the longitude. Returns false if the
	* Exif tags are not available.
	*/
	public boolean getLatLong(float output[]) {
	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);

	if (latValue != null && latRef != null && lngValue != null && lngRef != null) {
	output[0] = convertRationalLatLonToFloat(latValue, latRef);
	output[1] = convertRationalLatLonToFloat(lngValue, lngRef);
	return true;
	} else {
	return false;
	}
	}

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

	ParsePosition pos = new ParsePosition(0);
	try {
	Date datetime = sFormatter.parse(dateTimeString, pos);
	if (datetime == null) return -1;
	return datetime.getTime();
	} catch (IllegalArgumentException ex) {
	return -1;
	}
	}

	/**
	* Returns number of milliseconds since Jan. 1, 1970, midnight UTC.
	* Returns -1 if the date time information if not available.
	* @hide
	*/
	public long getGpsDateTime() {
	String date = mAttributes.get(TAG_GPS_DATESTAMP);
	String time = mAttributes.get(TAG_GPS_TIMESTAMP);
	if (date == null \|\| time == null) return -1;

	String dateTimeString = date + ' ' + time;
	if (dateTimeString == null) return -1;

	ParsePosition pos = new ParsePosition(0);
	try {
	Date datetime = sFormatter.parse(dateTimeString, pos);
	if (datetime == null) return -1;
	return datetime.getTime();
	} catch (IllegalArgumentException ex) {
	return -1;
	}
	}

	private static float convertRationalLatLonToFloat(
	String rationalString, String ref) {
	try {
	String [] parts = rationalString.split(",");

	String [] pair;
	pair = parts[0].split("/");
	int degrees = (int) (Float.parseFloat(pair[0].trim())
	/ Float.parseFloat(pair[1].trim()));

	pair = parts[1].split("/");
	int minutes = (int) ((Float.parseFloat(pair[0].trim())
	/ Float.parseFloat(pair[1].trim())));

	pair = parts[2].split("/");
	float seconds = Float.parseFloat(pair[0].trim())
	/ Float.parseFloat(pair[1].trim());

	float result = degrees + (minutes / 60F) + (seconds / (60F * 60F));
	if ((ref.equals("S") \|\| ref.equals("W"))) {
	return -result;
	}
	return result;
	} catch (RuntimeException ex) {
	// if for whatever reason we can't parse the lat long then return
	// null
	return 0f;
	}
	}

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

	private native void saveAttributesNative(String fileName,
	String compressedAttributes);

	private native String getAttributesNative(String fileName);

	private native void commitChangesNative(String fileName);

	private native byte[] getThumbnailNative(String fileName);
	}