1/*
2 * Copyright (C) 2015 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 com.android.usbtuner.exoplayer.ac3;
18
19import android.os.SystemClock;
20import android.util.Log;
21import android.util.Pair;
22
23import java.util.ArrayList;
24import java.util.HashSet;
25import java.util.Set;
26
27/**
28 * Monitors the rendering position of {@link AudioTrack}.
29 */
30public class AudioTrackMonitor {
31    private static final String TAG = "AudioTrackMonitor";
32    private static final boolean DEBUG = false;
33
34    // For fetched audio samples
35    private final ArrayList<Pair<Long, Integer>> mPtsList = new ArrayList<>();
36    private final Set<Integer> mSampleSize = new HashSet<>();
37    private final Set<Integer> mCurSampleSize = new HashSet<>();
38    private final Set<Integer> mAc3Header = new HashSet<>();
39
40    private long mExpireMs;
41    private long mDuration;
42    private long mSampleCount;
43    private long mTotalCount;
44    private long mStartMs;
45
46    private void flush() {
47        mExpireMs += mDuration;
48        mSampleCount = 0;
49        mCurSampleSize.clear();
50        mPtsList.clear();
51    }
52
53    /**
54     * Resets and initializes {@link AudioTrackMonitor}.
55     *
56     * @param duration the frequency of monitoring in milliseconds
57     */
58    public void reset(long duration) {
59        mExpireMs = SystemClock.elapsedRealtime();
60        mDuration = duration;
61        mTotalCount = 0;
62        mStartMs = 0;
63        mSampleSize.clear();
64        mAc3Header.clear();
65        flush();
66    }
67
68    /**
69     * Adds an audio sample information for monitoring.
70     *
71     * @param pts the presentation timestamp of the sample
72     * @param sampleSize the size in bytes of the sample
73     * @param header the bitrate &amp; sampling information header of the sample
74     */
75    public void addPts(long pts, int sampleSize, int header) {
76        mTotalCount++;
77        mSampleCount++;
78        mSampleSize.add(sampleSize);
79        mAc3Header.add(header);
80        mCurSampleSize.add(sampleSize);
81        if (mTotalCount == 1) {
82            mStartMs = SystemClock.elapsedRealtime();
83        }
84        if (mPtsList.isEmpty() || mPtsList.get(mPtsList.size() - 1).first != pts) {
85            mPtsList.add(Pair.create(pts, 1));
86            return;
87        }
88        Pair<Long, Integer> pair = mPtsList.get(mPtsList.size() - 1);
89        mPtsList.set(mPtsList.size() - 1, Pair.create(pair.first, pair.second + 1));
90    }
91
92    /**
93     * Logs if interested events are present.
94     * <p>
95     * Periodic logging is not enabled in release mode in order to avoid verbose logging.
96     */
97    public void maybeLog() {
98        long now = SystemClock.elapsedRealtime();
99        if (mExpireMs != 0 && now >= mExpireMs) {
100            if (DEBUG) {
101                long sampleDuration = (mTotalCount - 1) * Ac3TrackRenderer.AC3_SAMPLE_DURATION_US
102                        / 1000;
103                long totalDuration = now - mStartMs;
104                StringBuilder ptsBuilder = new StringBuilder();
105                ptsBuilder.append("PTS received ").append(mSampleCount).append(", ")
106                        .append(totalDuration - sampleDuration).append(' ');
107
108                for (Pair<Long, Integer> pair : mPtsList) {
109                    ptsBuilder.append('[').append(pair.first).append(':').append(pair.second)
110                            .append("], ");
111                }
112                Log.d(TAG, ptsBuilder.toString());
113            }
114            if (DEBUG || mCurSampleSize.size() > 1) {
115                Log.d(TAG, "PTS received sample size: "
116                        + String.valueOf(mSampleSize) + mCurSampleSize + mAc3Header);
117            }
118            flush();
119        }
120    }
121}
122