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Android Example MediaExtractor / MediaCodec / MediaSync
Raw
readme.md

readme.md

音声つき動画を MediaExtractor, MediaCodec, MediaSync を用いて再生するサンプルコードです。

minsdkversion=24 ですが、一箇所だけですので、minsdkversion=23 に簡単に落とせます。

実機で検証することをおすすめします。Android Emulator ではコーデックの不足等により、正しく動かないことがあります。

license

CC0

https://creativecommons.org/publicdomain/zero/1.0/deed.ja

Raw
MainActivity.java
package com.example.mediaprac;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.os.Handler;
import android.view.Surface;
import android.view.SurfaceView;
import android.view.TextureView;
import java.io.IOException;
public class MainActivity extends AppCompatActivity {
MyMedia mMedia = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final SurfaceView sv = findViewById(R.id.surfaceView1);
final Surface s = sv.getHolder().getSurface();
mMedia = new MyMedia(s, sv);
new Thread(new Runnable() {
@Override
public void run() {
mMedia.initialize();
mMedia.run();
}
}).start();
}
}
Raw
MyMedia.java
package com.example.mediaprac;
import android.media.AudioAttributes;
import android.media.AudioFormat;
import android.media.AudioTrack;
import android.media.MediaCodec;
import android.media.MediaCodecInfo;
import android.media.MediaCodecList;
import android.media.MediaExtractor;
import android.media.MediaFormat;
import android.media.MediaSync;
import android.media.PlaybackParams;
import android.media.SyncParams;
import android.os.Handler;
import android.util.Log;
import android.view.Surface;
import android.view.View;
import androidx.annotation.NonNull;
import java.io.IOException;
import java.nio.ByteBuffer;
public class MyMedia {
static final String TAG = "MyMedia";
private String mContentUri = "https://ia600603.us.archive.org/30/items/Tears-of-Steel/tears_of_steel_1080p.mp4";
// private String mContentUri = "https://scontent-nrt1-1.cdninstagram.com/v/t50.2886-16/41638619_239560346735367_5701419805668761311_n.mp4?_nc_ht=scontent-nrt1-1.cdninstagram.com&_nc_cat=103&_nc_ohc=NN0ddOIY3fUAX81uvbP&oe=5E5992B3&oh=f3f3097a6daa345e82fc5c0f12c7cb24";
private boolean mRunning;
private View mView;
private Surface mGivenSurface, mSurface;
private AudioTrack mAudioTrack;
private MediaSync mSync;
private MediaExtractor mVideoExtractor, mAudioExtractor;
private MediaCodec mVideoCodec, mAudioCodec;
static private MediaExtractor createExtractor(String uri){
MediaExtractor extractor = new MediaExtractor();
try {
extractor.setDataSource(uri);
} catch (IOException e) {
e.printStackTrace();
extractor.release();
return null;
}
return extractor;
}
static private int[] findTrackAVIndex(MediaExtractor extractor) {
int[] ii = new int[2];
ii[0] = -1; // video
ii[1] = -1; // audio
for (int i = 0, n = extractor.getTrackCount(); i < n; ++i) {
MediaFormat format = extractor.getTrackFormat(i);
String mime = format.getString(MediaFormat.KEY_MIME);
Log.d(TAG, "track " + i + " : key_mime = " + mime);
if (mime == null) continue;
if (mime.contains("video"))
ii[0] = i;
else if (mime.contains("audio"))
ii[1] = i;
}
return ii;
}
static private MediaCodec createMediaCodec(MediaFormat format){
assert format != null;
String codecName = new MediaCodecList(MediaCodecList.ALL_CODECS).findDecoderForFormat(format);
MediaCodec codec = null;
try {
String mime = format.getString(MediaFormat.KEY_MIME);
Log.d(TAG, "try to create a codec mime="+mime+" codecName="+codecName);
if (codecName != null)
codec = MediaCodec.createByCodecName(codecName);
else if (mime != null)
codec = MediaCodec.createDecoderByType(mime); // may be throw IllegalArgumentException
} catch (IOException e) {
e.printStackTrace();
return null;
}
return codec;
}
static private MediaCodec createVideoDecoder(MediaFormat format, Surface surface) {
MediaCodec codec = createMediaCodec(format);
if (codec == null)
return null;
codec.configure(format, surface, null, 0);
return codec;
}
static private MediaCodec createAudioDecoder(MediaFormat format) {
MediaCodec codec = createMediaCodec(format);
if (codec == null)
return null;
codec.configure(format, null, null, 0);
return codec;
}
static private AudioFormat createAudioFormatFromMediaFormat(MediaFormat mediaFormat) {
AudioFormat.Builder b = new AudioFormat.Builder();
if (mediaFormat.containsKey(MediaFormat.KEY_SAMPLE_RATE)) {
b.setSampleRate(mediaFormat.getInteger(MediaFormat.KEY_SAMPLE_RATE));
}
else {
Log.w(TAG, "createAudioFormatFormMediaFormat: not found KEY_SAMPLE_RATE");
b.setSampleRate(44100);
}
if (mediaFormat.containsKey(MediaFormat.KEY_PCM_ENCODING)) {
b.setEncoding(mediaFormat.getInteger(MediaFormat.KEY_PCM_ENCODING));
}
else {
Log.w(TAG, "createAudioFormatFormMediaFormat: not found KEY_PCM_ENCODING");
b.setEncoding(AudioFormat.ENCODING_PCM_16BIT);
}
if (mediaFormat.containsKey(MediaFormat.KEY_CHANNEL_MASK)) {
b.setChannelMask(mediaFormat.getInteger(MediaFormat.KEY_CHANNEL_MASK));
}
else {
Log.w(TAG, "createAudioFormatFormMediaFormat: not found KEY_CHANNEL_MASK");
b.setChannelMask(AudioFormat.CHANNEL_OUT_STEREO);
}
return b.build();
}
static private AudioTrack createAudioTrack(AudioFormat audioFormat) {
int size = AudioTrack.getMinBufferSize(audioFormat.getSampleRate(),
audioFormat.getChannelMask(), audioFormat.getEncoding());
return new AudioTrack.Builder()
.setAudioAttributes(new AudioAttributes.Builder()
.setUsage(AudioAttributes.USAGE_MEDIA)
.setContentType(AudioAttributes.CONTENT_TYPE_MOVIE)
.build())
.setAudioFormat(audioFormat)
.setTransferMode(AudioTrack.MODE_STREAM)
.setBufferSizeInBytes(size)
.build();
}
static private void dumpMediaCodecList() {
MediaCodecList mcl = new MediaCodecList(MediaCodecList.ALL_CODECS);
for (MediaCodecInfo mci : mcl.getCodecInfos()) {
for (String type : mci.getSupportedTypes()) {
Log.d(TAG, mci.getName() + " supports " + type);
}
}
}
public MyMedia(Surface surface, View view) {
assert surface != null;
mRunning = false;
mView = view;
mGivenSurface = surface;
dumpMediaCodecList();
}
public boolean initialize() {
Log.d(TAG, "[1]initialize");
mRunning = false;
MediaExtractor extractor = createExtractor(mContentUri);
if (extractor == null) {
Log.w(TAG, "createExtractor failed.");
return false;
}
mSync = new MediaSync();
mSync.setPlaybackParams(new PlaybackParams().setSpeed(0.f));
mSync.setSurface(mGivenSurface);
mSurface = mSync.createInputSurface();
int videoTrackIndex, audioTrackIndex;
{
int[] ii = findTrackAVIndex(extractor);
videoTrackIndex = ii[0];
audioTrackIndex = ii[1];
if (videoTrackIndex < 0) {
Log.w(TAG, "videoTrack not found");
return false;
}
if (audioTrackIndex < 0) {
Log.w(TAG, "audioTrack not found");
return false;
}
Log.d(TAG, "videoTrackIndex=" + videoTrackIndex + " audioTrackIndex="+audioTrackIndex);
}
MediaFormat audioMediaFormat = extractor.getTrackFormat(audioTrackIndex);
mVideoExtractor = createExtractor(mContentUri);
assert mVideoExtractor != null;
mVideoExtractor.selectTrack(videoTrackIndex);
mVideoCodec = createVideoDecoder(extractor.getTrackFormat(videoTrackIndex), mSurface);
mAudioExtractor = createExtractor(mContentUri);
assert mAudioExtractor != null;
mAudioExtractor.selectTrack(audioTrackIndex);
mAudioCodec = createAudioDecoder(extractor.getTrackFormat(audioTrackIndex));
mAudioTrack = createAudioTrack(createAudioFormatFromMediaFormat(audioMediaFormat));
mSync.setAudioTrack(mAudioTrack);
mSync.setSyncParams(new SyncParams()
.setSyncSource(SyncParams.SYNC_SOURCE_SYSTEM_CLOCK));
Log.d(TAG, "[2]initialize");
return true;
}
public void release() {
Log.d(TAG, "[1]release");
mRunning = false;
mVideoExtractor.release();
mVideoCodec.release();
mAudioExtractor.release();
mAudioCodec.release();
mAudioTrack.release();
mSync.release();
Log.d(TAG, "[2]release");
}
void run() {
Log.d(TAG, "[1]run");
mRunning = true;
mVideoCodec.setCallback(new CodecCallback(mVideoExtractor, mSync, false));
mAudioCodec.setCallback(new CodecCallback(mAudioExtractor, mSync, true));
mSync.setCallback(new MediaSync.Callback() {
@Override
public void onAudioBufferConsumed(MediaSync sync, ByteBuffer audioBuffer, int bufferId) {
Log.d(TAG, "onAudioBufferConsumed " + bufferId);
mAudioCodec.releaseOutputBuffer(bufferId, true);
}
}, null);// This needs to be done since sync is paused on creation.
mVideoCodec.start();
mAudioCodec.start();
new Thread(new Runnable() {
@Override
public void run() {
Log.d(TAG, "ready...");
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
}
mSync.setPlaybackParams(new PlaybackParams().setSpeed(1.f));
Log.d(TAG, "play !!!!!!");
;
}
}).start();
Log.d(TAG, "[2]run");
}
class CodecCallback extends MediaCodec.Callback {
MediaExtractor mExtractor;
MediaSync mSync;
boolean mIsAudio;
CodecCallback(MediaExtractor extractor, MediaSync sync, boolean isAudio) {
mExtractor = extractor;
mSync = sync;
mIsAudio = isAudio;
}
private String getTag() {
return mIsAudio ? "Audio" : "Video";
}
@Override
public void onInputBufferAvailable(@NonNull MediaCodec mediaCodec, int index) {
Log.d(TAG, "onInputBufferAvailable " + getTag() + " i=" + index);
ByteBuffer buffer = mediaCodec.getInputBuffer(index);
if (buffer == null) {
Log.w(TAG, "codec buffer is null");
return;
}
int size = mExtractor.readSampleData(buffer, 0);
if (size < 0) {
Log.w(TAG, "track empty");
return;
}
long time = mExtractor.getSampleTime();
Log.d(TAG, "sampleTime=" + time);
mediaCodec.queueInputBuffer(
index, 0, size,
time, 0);
mExtractor.advance();
}
@Override
public void onOutputBufferAvailable(@NonNull MediaCodec mediaCodec, int index, @NonNull MediaCodec.BufferInfo bufferInfo) {
Log.d(TAG, "onOutputBufferAvailable " + getTag() + " i=" + index + " timeMs="+bufferInfo.presentationTimeUs/1000);
if (mIsAudio) {
ByteBuffer buffer = mediaCodec.getOutputBuffer(index);
if (buffer == null) {
Log.w(TAG, "buffer is null");
return;
}
mSync.queueAudio(buffer, index, bufferInfo.presentationTimeUs);
}
else {
mediaCodec.releaseOutputBuffer(index, bufferInfo.presentationTimeUs*1000); // renderTimestampNs
}
}
@Override
public void onError(@NonNull MediaCodec mediaCodec, @NonNull MediaCodec.CodecException e) {
Log.e(TAG, "codec: onError " + getTag());
e.printStackTrace();
}
@Override
public void onOutputFormatChanged(@NonNull MediaCodec mediaCodec, @NonNull MediaFormat mediaFormat) {
Log.w(TAG, "codec: onOutputFormatChanged " + getTag());
}
}
}
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