云南微网站制作,网站内容优化,wordpress图片代码,企迪网本文实例讲述了Android开发之使用ExifInterface获取拍照后的图片属性。分享给大家供大家参考#xff0c;具体如下#xff1a;ExifInterface exif new ExifInterface(file.getPath());String widthStr exif.getAttribute(ExifInterface.TAG_IMAGE_WIDTH);String heightStr …本文实例讲述了Android开发之使用ExifInterface获取拍照后的图片属性。分享给大家供大家参考具体如下ExifInterface exif new ExifInterface(file.getPath());String widthStr exif.getAttribute(ExifInterface.TAG_IMAGE_WIDTH);String heightStr exif.getAttribute(ExifInterface.TAG_IMAGE_LENGTH);....../** 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/** Type is int. */public static final String TAG_ORIENTATION Orientation;/** Type is String. */public static final String TAG_DATETIME DateTime;/** Type is String. */public static final String TAG_MAKE Make;/** Type is String. */public static final String TAG_MODEL Model;/** Type is int. */public static final String TAG_FLASH Flash;/** Type is int. */public static final String TAG_IMAGE_WIDTH ImageWidth;/** Type is int. */public static final String TAG_IMAGE_LENGTH ImageLength;/** String. Format is num1/denom1,num2/denom2,num3/denom3. */public static final String TAG_GPS_LATITUDE GPSLatitude;/** String. Format is num1/denom1,num2/denom2,num3/denom3. */public static final String TAG_GPS_LONGITUDE GPSLongitude;/** Type is String. */public static final String TAG_GPS_LATITUDE_REF GPSLatitudeRef;/** Type is String. */public static final String TAG_GPS_LONGITUDE_REF GPSLongitudeRef;/** Type is String. */public static final String TAG_GPS_TIMESTAMP GPSTimeStamp;/** Type is String. */public static final String TAG_GPS_DATESTAMP GPSDateStamp;/** Type is int. */public static final String TAG_WHITE_BALANCE WhiteBalance;/** Type is rational. */public static final String TAG_FOCAL_LENGTH FocalLength;/** Type is String. Name of GPS processing method used for location finding. */public static final String TAG_GPS_PROCESSING_METHOD GPSProcessingMethod;// 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 mirrorpublic static final int ORIENTATION_ROTATE_180 3;public static final int ORIENTATION_FLIP_VERTICAL 4; // upside down mirrorpublic static final int ORIENTATION_TRANSPOSE 5; // flipped about top-left bottom-right axispublic static final int ORIENTATION_ROTATE_90 6; // rotate 90 cw to right itpublic static final int ORIENTATION_TRANSVERSE 7; // flipped about top-right bottom-left axispublic static final int ORIENTATION_ROTATE_270 8; // rotate 270 to right it// Constants used for white balancepublic 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 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* defaultValue.** 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;}}/*** Returns the double value of the specified rational tag. If there is no* such tag in the JPEG file or the value cannot be parsed as double, return* defaultValue.** param tag the name of the tag.* param defaultValue the value to return if the tag is not available.*/public double getAttributeDouble(String tag, double defaultValue) {String value mAttributes.get(tag);if (value null) return defaultValue;try {int index value.indexOf(/);if (index -1) return defaultValue;double denom Double.parseDouble(value.substring(index 1));if (denom 0) return defaultValue;double num Double.parseDouble(value.substring(0, index));return num / denom;} 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 tags 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 attr1valueLen value1attr2value2Len value2...// example:// 4 attrPtr ImageLength4 1024Model6 FooImageWidth4 1280Make3 FOOmAttributes new HashMap();String attrStr;synchronized (sLock) {attrStr getAttributesNative(mFilename);}// get countint ptr attrStr.indexOf( );int count Integer.parseInt(attrStr.substring(0, ptr));// skip past the space between item count and the rest of the attributesptr;for (int i 0; i count; i) {// extract the attribute nameint equalPos attrStr.indexOf(, ptr);String attrName attrStr.substring(ptr, equalPos);ptr equalPos 1; // skip past // extract the attribute value lengthint lenPos attrStr.indexOf( , ptr);int attrLen Integer.parseInt(attrStr.substring(ptr, lenPos));ptr lenPos 1; // skip pas the space// extract the attribute valueString 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. Its 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 attr1valueLen value1attr2value2Len value2...// example:// 4 attrPtr ImageLength4 1024Model6 FooImageWidth4 1280Make3 FOOStringBuilder sb new StringBuilder();int size mAttributes.size();if (mAttributes.containsKey(hasThumbnail)) {--size;}sb.append(size );for (Map.Entry iter : mAttributes.entrySet()) {String key iter.getKey();if (key.equals(hasThumbnail)) {// this is a fake attribute not saved as an exif tagcontinue;}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 cant parse the lat long then return// nullreturn 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);}更多关于Android开发相关内容感兴趣的读者可查看本站专题《Android开发入门与进阶教程》及《Android图形与图像处理技巧总结》希望本文所述对大家Android程序设计有所帮助。
