好时光
春分已过，下个时节就是清明了，送上古人小诗一首：
咏柳
【作者】贺知章 【朝代】唐
碧玉妆成一树高，万条垂下绿丝绦。
不知细叶谁裁出，二月春风似剪刀。
MediaExtractor 抽取视频不含音频
/**
* 抽取（ly.mp4）的视频文件不含音频
*/
@TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR2)
@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN)
private void extracMedia() {
MediaExtractor mMediaExtractor = new MediaExtractor();
try {
mMediaExtractor.setDataSource(MEDIA_VIDEO_PATH);
//获取通道的个数
int trackCount = mMediaExtractor.getTrackCount();
int videoIndex = -1;
for (int i = 0; i < trackCount; i++) {
//这个trackFormat可不得了可以获取视频的宽高，视频的通道（音频视频），获取视频的长。有的人用这个获取帧率我试过，有的手机行有的
//不行，会报错。这是个坑，所以还是另求方式
MediaFormat trackFormat = mMediaExtractor.getTrackFormat(i);
String typeMimb = trackFormat.getString(MediaFormat.KEY_MIME);
if (typeMimb.startsWith("video/")) {
//这就获取了音频的信号通道了
videoIndex = i;
break;
}
}
//设置音频通道信号
mMediaExtractor.selectTrack(videoIndex);
//再次拿到这个视频通道的format
MediaFormat trackFormat = mMediaExtractor.getTrackFormat(videoIndex);
//初始化视频合成器
MediaMuxer mediaMuxer = new MediaMuxer(BASE_PATH + "/out_ly.mp4", MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);
//添加给合成器的通道
mediaMuxer.addTrack(trackFormat);
ByteBuffer allocate = ByteBuffer.allocate(500 * 1024);
mediaMuxer.start();
//获取视频的帧率
long videoSametime = 0;
mMediaExtractor.readSampleData(allocate, 0);
//跳过I帧，要P帧（视频是由个别I帧和很多P帧组成）
if (mMediaExtractor.getSampleFlags() == MediaExtractor.SAMPLE_FLAG_SYNC) {
mMediaExtractor.advance();
}
mMediaExtractor.readSampleData(allocate, 0);
long firstTime = mMediaExtractor.getSampleTime();
//下一帧
mMediaExtractor.advance();
mMediaExtractor.readSampleData(allocate, 0);
long senondTime = mMediaExtractor.getSampleTime();
videoSametime = Math.abs(senondTime - firstTime);
//重新设置通道读取文件
mMediaExtractor.unselectTrack(videoIndex);
mMediaExtractor.selectTrack(videoIndex);
MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();
while (true) {
int readSamSize = mMediaExtractor.readSampleData(allocate, 0);
if (readSamSize < 0) {
break;
}
mMediaExtractor.advance();
bufferInfo.flags = mMediaExtractor.getSampleFlags();
bufferInfo.size = readSamSize;
bufferInfo.offset = 0;
bufferInfo.presentationTimeUs += videoSametime;
mediaMuxer.writeSampleData(videoIndex, allocate, bufferInfo);
}
mediaMuxer.stop();
mediaMuxer.release();
mMediaExtractor.release();
Log.e("av", "success!");
} catch (IOException e) {
e.printStackTrace();
}
}
MediaExtractor 抽取音频不含视频
@TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR2)
@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN)
private void extracAudio() {
MediaExtractor mediaExtractor = new MediaExtractor();
try {
mediaExtractor.setDataSource(AUDIO_VIDEO_PATH);
int trackCount = mediaExtractor.getTrackCount();
int audioIndex = -1;
for (int i = 0; i < trackCount; i++) {
MediaFormat trackFormat = mediaExtractor.getTrackFormat(i);
String type = trackFormat.getString(MediaFormat.KEY_MIME);
if (type.startsWith("audio/")) {
audioIndex = i;
}
}
mediaExtractor.selectTrack(audioIndex);
MediaFormat trackFormat = mediaExtractor.getTrackFormat(audioIndex);
MediaMuxer mediaMuxer = new MediaMuxer(BASE_PATH + "/out_eat", MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);
int writeAudio = mediaMuxer.addTrack(trackFormat);
mediaMuxer.start();
ByteBuffer buffer = ByteBuffer.allocate(1024 * 500);
MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();
long sampleTime = 0;
mediaExtractor.readSampleData(buffer, 0);
if (mediaExtractor.getSampleFlags() == MediaExtractor.SAMPLE_FLAG_SYNC) {
mediaExtractor.advance();
}
mediaExtractor.readSampleData(buffer, 0);
long firstTime = mediaExtractor.getSampleTime();
mediaExtractor.advance();
// mediaExtractor.readSampleData(buffer, 0);
long secondeTime = mediaExtractor.getSampleTime();
sampleTime = Math.abs(secondeTime - firstTime);
mediaExtractor.unselectTrack(audioIndex);
mediaExtractor.selectTrack(audioIndex);
while (true) {
int readSize = mediaExtractor.readSampleData(buffer, 0);
if (readSize < 0) {
break;
}
// mediaExtractor.readSampleData(buffer, 0);
mediaExtractor.advance();
bufferInfo.size = readSize;
bufferInfo.flags = mediaExtractor.getSampleFlags();
bufferInfo.offset = 0;
bufferInfo.presentationTimeUs = +sampleTime;
mediaMuxer.writeSampleData(writeAudio, buffer, bufferInfo);
}
mediaMuxer.stop();
mediaMuxer.release();
mediaExtractor.release();
Log.e("av", "success");
} catch (IOException e) {
e.printStackTrace();
}
}
MediaExtractor 抽取视频音频文件，然后利用MediaMuxer合成
@TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR2)
@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN)
private void combineVideo() {
//用生成的out_ly.map4 和音频out_eat 合成一个新的eat_ly.mp4
try {
MediaExtractor videoExtractor = new MediaExtractor();
videoExtractor.setDataSource(BASE_PATH + "/out_ly.mp4");
MediaFormat videoFormat = null;
int videoTrackIndex = -1;
int videoTrackCount = videoExtractor.getTrackCount();
for (int i = 0; i < videoTrackCount; i++) {
videoFormat = videoExtractor.getTrackFormat(i);
String mimeType = videoFormat.getString(MediaFormat.KEY_MIME);
if (mimeType.startsWith("video/")) {
videoTrackIndex = i;
break;
}
}
MediaExtractor audioExtractor = new MediaExtractor();
audioExtractor.setDataSource(BASE_PATH + "/out_eat");
MediaFormat audioFormat = null;
int audioTrackIndex = -1;
int audioTrackCount = audioExtractor.getTrackCount();
for (int i = 0; i < audioTrackCount; i++) {
audioFormat = audioExtractor.getTrackFormat(i);
String mimeType = audioFormat.getString(MediaFormat.KEY_MIME);
if (mimeType.startsWith("audio/")) {
audioTrackIndex = i;
break;
}
}
videoExtractor.selectTrack(videoTrackIndex);
audioExtractor.selectTrack(audioTrackIndex);
MediaCodec.BufferInfo videoBufferInfo = new MediaCodec.BufferInfo();
MediaCodec.BufferInfo audioBufferInfo = new MediaCodec.BufferInfo();
MediaMuxer mediaMuxer = new MediaMuxer(BASE_PATH + "/eat_ly.mp4", MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);
int writeVideoTrackIndex = mediaMuxer.addTrack(videoFormat);
int writeAudioTrackIndex = mediaMuxer.addTrack(audioFormat);
mediaMuxer.start();
ByteBuffer byteBuffer = ByteBuffer.allocate(500 * 1024);
long sampleTime = 0;
{
videoExtractor.readSampleData(byteBuffer, 0);
if (videoExtractor.getSampleFlags() == MediaExtractor.SAMPLE_FLAG_SYNC) {
videoExtractor.advance();
}
videoExtractor.readSampleData(byteBuffer, 0);
long secondTime = videoExtractor.getSampleTime();
videoExtractor.advance();
long thirdTime = videoExtractor.getSampleTime();
sampleTime = Math.abs(thirdTime - secondTime);
}
videoExtractor.unselectTrack(videoTrackIndex);
videoExtractor.selectTrack(videoTrackIndex);
long stampTimeAudio = 0;
ByteBuffer byteBufferAudio = ByteBuffer.allocate(500 * 1024);
//获取帧之间的间隔时间
{
audioExtractor.readSampleData(byteBufferAudio, 0);
if (audioExtractor.getSampleFlags() == MediaExtractor.SAMPLE_FLAG_SYNC) {
audioExtractor.advance();
}
audioExtractor.readSampleData(byteBufferAudio, 0);
long secondTime = audioExtractor.getSampleTime();
audioExtractor.advance();
long thirdTime = audioExtractor.getSampleTime();
stampTimeAudio = Math.abs(thirdTime - secondTime);
Log.e("fuck", stampTimeAudio + "");
}
audioExtractor.unselectTrack(audioTrackIndex);
audioExtractor.selectTrack(audioTrackIndex);
while (true) {
int readVideoSampleSize = videoExtractor.readSampleData(byteBuffer, 0);
if (readVideoSampleSize < 0) {
break;
}
videoBufferInfo.size = readVideoSampleSize;
videoBufferInfo.presentationTimeUs += sampleTime;
videoBufferInfo.offset = 0;
videoBufferInfo.flags = videoExtractor.getSampleFlags();
mediaMuxer.writeSampleData(writeVideoTrackIndex, byteBuffer, videoBufferInfo);
videoExtractor.advance();
}
while (true) {
int readAudioSampleSize = audioExtractor.readSampleData(byteBufferAudio, 0);
if (readAudioSampleSize < 0) {
break;
}
audioBufferInfo.size = readAudioSampleSize;
audioBufferInfo.presentationTimeUs += stampTimeAudio;
audioBufferInfo.offset = 0;
audioBufferInfo.flags = audioExtractor.getSampleFlags();
mediaMuxer.writeSampleData(writeAudioTrackIndex, byteBufferAudio, audioBufferInfo);
audioExtractor.advance();
}
mediaMuxer.stop();
mediaMuxer.release();
videoExtractor.release();
audioExtractor.release();
} catch (IOException e) {
e.printStackTrace();
}
}