/*
* Copyright (C) 2008 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 android.content.ContentResolver;
import android.content.Context;
import android.content.res.AssetFileDescriptor;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.ParcelFileDescriptor;
import java.io.FileDescriptor;
import java.io.IOException;
import java.io.FileNotFoundException;
/**
* MediaMetadataRetriever class provides a unified interface for retrieving
* frame and meta data from an input media file.
* {@hide}
*/
public class MediaMetadataRetriever
{
static {
System.loadLibrary("media_jni");
}
// The field below is accessed by native methods
@SuppressWarnings("unused")
private int mNativeContext;
public MediaMetadataRetriever() {
native_setup();
}
/**
* Call this method before setDataSource() so that the mode becomes
* effective for subsequent operations. This method can be called only once
* at the beginning if the intended mode of operation for a
* MediaMetadataRetriever object remains the same for its whole lifetime,
* and thus it is unnecessary to call this method each time setDataSource()
* is called. If this is not never called (which is allowed), by default the
* intended mode of operation is to both capture frame and retrieve meta
* data (i.e., MODE_GET_METADATA_ONLY | MODE_CAPTURE_FRAME_ONLY).
* Often, this may not be what one wants, since doing this has negative
* performance impact on execution time of a call to setDataSource(), since
* both types of operations may be time consuming.
*
* @param mode The intended mode of operation. Can be any combination of
* MODE_GET_METADATA_ONLY and MODE_CAPTURE_FRAME_ONLY:
* 1. MODE_GET_METADATA_ONLY & MODE_CAPTURE_FRAME_ONLY:
* For neither frame capture nor meta data retrieval
* 2. MODE_GET_METADATA_ONLY: For meta data retrieval only
* 3. MODE_CAPTURE_FRAME_ONLY: For frame capture only
* 4. MODE_GET_METADATA_ONLY | MODE_CAPTURE_FRAME_ONLY:
* For both frame capture and meta data retrieval
*/
public native void setMode(int mode);
/**
* @return the current mode of operation. A negative return value indicates
* some runtime error has occurred.
*/
public native int getMode();
/**
* Sets the data source (file pathname) to use. Call this
* method before the rest of the methods in this class. This method may be
* time-consuming.
*
* @param path The path of the input media file.
* @throws IllegalArgumentException If the path is invalid.
*/
public native void setDataSource(String path) throws IllegalArgumentException;
/**
* Sets the data source (FileDescriptor) to use. It is the caller's
* responsibility to close the file descriptor. It is safe to do so as soon
* as this call returns. Call this method before the rest of the methods in
* this class. This method may be time-consuming.
*
* @param fd the FileDescriptor for the file you want to play
* @param offset the offset into the file where the data to be played starts,
* in bytes. It must be non-negative
* @param length the length in bytes of the data to be played. It must be
* non-negative.
* @throws IllegalArgumentException if the arguments are invalid
*/
public native void setDataSource(FileDescriptor fd, long offset, long length)
throws IllegalArgumentException;
/**
* Sets the data source (FileDescriptor) to use. It is the caller's
* responsibility to close the file descriptor. It is safe to do so as soon
* as this call returns. Call this method before the rest of the methods in
* this class. This method may be time-consuming.
*
* @param fd the FileDescriptor for the file you want to play
* @throws IllegalArgumentException if the FileDescriptor is invalid
*/
public void setDataSource(FileDescriptor fd)
throws IllegalArgumentException {
// intentionally less than LONG_MAX
setDataSource(fd, 0, 0x7ffffffffffffffL);
}
/**
* Sets the data source as a content Uri. Call this method before
* the rest of the methods in this class. This method may be time-consuming.
*
* @param context the Context to use when resolving the Uri
* @param uri the Content URI of the data you want to play
* @throws IllegalArgumentException if the Uri is invalid
* @throws SecurityException if the Uri cannot be used due to lack of
* permission.
*/
public void setDataSource(Context context, Uri uri)
throws IllegalArgumentException, SecurityException {
if (uri == null) {
throw new IllegalArgumentException();
}
String scheme = uri.getScheme();
if(scheme == null || scheme.equals("file")) {
setDataSource(uri.getPath());
return;
}
AssetFileDescriptor fd = null;
try {
ContentResolver resolver = context.getContentResolver();
try {
fd = resolver.openAssetFileDescriptor(uri, "r");
} catch(FileNotFoundException e) {
throw new IllegalArgumentException();
}
if (fd == null) {
throw new IllegalArgumentException();
}
FileDescriptor descriptor = fd.getFileDescriptor();
if (!descriptor.valid()) {
throw new IllegalArgumentException();
}
// Note: using getDeclaredLength so that our behavior is the same
// as previous versions when the content provider is returning
// a full file.
if (fd.getDeclaredLength() < 0) {
setDataSource(descriptor);
} else {
setDataSource(descriptor, fd.getStartOffset(), fd.getDeclaredLength());
}
return;
} catch (SecurityException ex) {
} finally {
try {
if (fd != null) {
fd.close();
}
} catch(IOException ioEx) {
}
}
setDataSource(uri.toString());
}
/**
* Call this method after setDataSource(). This method retrieves the
* meta data value associated with the keyCode.
*
* The keyCode currently supported is listed below as METADATA_XXX
* constants. With any other value, it returns a null pointer.
*
* @param keyCode One of the constants listed below at the end of the class.
* @return The meta data value associate with the given keyCode on success;
* null on failure.
*/
public native String extractMetadata(int keyCode);
/**
* Call this method after setDataSource(). This method finds a
* representative frame if successful and returns it as a bitmap. This is
* useful for generating a thumbnail for an input media source.
*
* @return A Bitmap containing a representative video frame, which
* can be null, if such a frame cannot be retrieved.
*/
public native Bitmap captureFrame();
/**
* Call this method after setDataSource(). This method finds the optional
* graphic or album art associated (embedded or external url linked) the
* related data source.
*
* @return null if no such graphic is found.
*/
public native byte[] extractAlbumArt();
/**
* Call it when one is done with the object. This method releases the memory
* allocated internally.
*/
public native void release();
private native void native_setup();
private native final void native_finalize();
@Override
protected void finalize() throws Throwable {
try {
native_finalize();
} finally {
super.finalize();
}
}
public static final int MODE_GET_METADATA_ONLY = 0x01;
public static final int MODE_CAPTURE_FRAME_ONLY = 0x02;
/*
* Do not change these values without updating their counterparts
* in include/media/mediametadataretriever.h!
*/
public static final int METADATA_KEY_CD_TRACK_NUMBER = 0;
public static final int METADATA_KEY_ALBUM = 1;
public static final int METADATA_KEY_ARTIST = 2;
public static final int METADATA_KEY_AUTHOR = 3;
public static final int METADATA_KEY_COMPOSER = 4;
public static final int METADATA_KEY_DATE = 5;
public static final int METADATA_KEY_GENRE = 6;
public static final int METADATA_KEY_TITLE = 7;
public static final int METADATA_KEY_YEAR = 8;
public static final int METADATA_KEY_DURATION = 9;
public static final int METADATA_KEY_NUM_TRACKS = 10;
public static final int METADATA_KEY_IS_DRM_CRIPPLED = 11;
public static final int METADATA_KEY_CODEC = 12;
public static final int METADATA_KEY_RATING = 13;
public static final int METADATA_KEY_COMMENT = 14;
public static final int METADATA_KEY_COPYRIGHT = 15;
public static final int METADATA_KEY_BIT_RATE = 16;
public static final int METADATA_KEY_FRAME_RATE = 17;
public static final int METADATA_KEY_VIDEO_FORMAT = 18;
public static final int METADATA_KEY_VIDEO_HEIGHT = 19;
public static final int METADATA_KEY_VIDEO_WIDTH = 20;
// Add more here...
}
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