MediaExtractor.java revision c52b980277f08aee7981b1fdbca7a89464cf66d9 
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*/
26public class MediaExtractor
27{
28    public MediaExtractor(String path) {
29        native_setup(path);
30    }
31
32    @Override
33    protected void finalize() {
34        native_finalize();
35    }
36
37    // Make sure you call this when you're done to free up any resources
38    // instead of relying on the garbage collector to do this for you at
39    // some point in the future.
40    public native final void release();
41
42    public native int countTracks();
43    public native Map<String, Object> getTrackFormat(int index);
44
45    // Subsequent calls to "readSampleData", "getSampleTrackIndex" and
46    // "getSampleTime" only retrieve information for the subset of tracks
47    // selected by the call below.
48    // Selecting the same track multiple times has no effect, the track
49    // is only selected once.
50    public native void selectTrack(int index);
51
52    // All selected tracks seek near the requested time. The next sample
53    // returned for each selected track will be a sync sample.
54    public native void seekTo(long timeUs);
55
56    public native boolean advance();
57
58    // Retrieve the current encoded sample and store it in the byte buffer
59    // starting at the given offset. Returns the sample size.
60    public native int readSampleData(ByteBuffer byteBuf, int offset);
61
62    // Returns the track index the current sample originates from.
63    public native int getSampleTrackIndex();
64
65    // Returns the current sample's presentation time in microseconds.
66    public native long getSampleTime();
67
68    private static native final void native_init();
69    private native final void native_setup(String path);
70    private native final void native_finalize();
71
72    static {
73        System.loadLibrary("media_jni");
74        native_init();
75    }
76
77    private int mNativeContext;
78}
79