MediaExtractor.java revision 8240d9239d9aabed75c49f9d4d69fd8a5fe4c899 
1/*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.media;
18
19import java.nio.ByteBuffer;
20import java.util.Map;
21
22/**
23 * MediaExtractor
24 * @hide
25*/
26final public class MediaExtractor {
27    public MediaExtractor(String path) {
28        native_setup(path);
29    }
30
31    @Override
32    protected void finalize() {
33        native_finalize();
34    }
35
36    // Make sure you call this when you're done to free up any resources
37    // instead of relying on the garbage collector to do this for you at
38    // some point in the future.
39    public native final void release();
40
41    public native int countTracks();
42    public native Map<String, Object> getTrackFormat(int index);
43
44    // Subsequent calls to "readSampleData", "getSampleTrackIndex" and
45    // "getSampleTime" only retrieve information for the subset of tracks
46    // selected by the call below.
47    // Selecting the same track multiple times has no effect, the track
48    // is only selected once.
49    public native void selectTrack(int index);
50
51    // All selected tracks seek near the requested time. The next sample
52    // returned for each selected track will be a sync sample.
53    public native void seekTo(long timeUs);
54
55    public native boolean advance();
56
57    // Retrieve the current encoded sample and store it in the byte buffer
58    // starting at the given offset. Returns the sample size.
59    public native int readSampleData(ByteBuffer byteBuf, int offset);
60
61    // Returns the track index the current sample originates from.
62    public native int getSampleTrackIndex();
63
64    // Returns the current sample's presentation time in microseconds.
65    public native long getSampleTime();
66
67    // Keep these in sync with their equivalents in NuMediaExtractor.h
68    public static final int SAMPLE_FLAG_SYNC      = 1;
69    public static final int SAMPLE_FLAG_ENCRYPTED = 2;
70
71    // Returns the current sample's flags.
72    public native int getSampleFlags();
73
74    private static native final void native_init();
75    private native final void native_setup(String path);
76    private native final void native_finalize();
77
78    static {
79        System.loadLibrary("media_jni");
80        native_init();
81    }
82
83    private int mNativeContext;
84}
85