我想将视频(mp4)转换为mp3格式。如果有人知道，请解释一下。
我已经尝试过，但它没有起作用。
我从这个链接中实现了它，但对我来说不起作用。 如何在Android中使用Java从mp4提取音频到mp3？
public class AudioFromVideo {
private String audio, video;
private MediaCodec amc;
private MediaExtractor ame;
private MediaFormat amf;
private String amime;
public AudioFromVideo(String srcVideo, String destAudio) {
this.audio = destAudio;
this.video = srcVideo;
ame = new MediaExtractor();
init();
}
public void init() {
try {
ame.setDataSource(video);
amf = ame.getTrackFormat(1);
ame.selectTrack(1);
amime = amf.getString(MediaFormat.KEY_MIME);
amc = MediaCodec.createDecoderByType(amime);
amc.configure(amf, null, null, 0);
amc.start();
} catch (IOException e) {
e.printStackTrace();
}
}
public void start() {
new AudioService(amc, ame, audio).start();
}
private class AudioService extends Thread {
private MediaCodec amc;
private MediaExtractor ame;
private ByteBuffer[] aInputBuffers, aOutputBuffers;
private String destFile;
@SuppressWarnings("deprecation")
AudioService(MediaCodec amc, MediaExtractor ame, String destFile) {
this.amc = amc;
this.ame = ame;
this.destFile = destFile;
aInputBuffers = amc.getInputBuffers();
aOutputBuffers = amc.getOutputBuffers();
}
@SuppressWarnings("deprecation")
public void run() {
try {
OutputStream os = new FileOutputStream(new File(destFile));
long count = 0;
while (true) {
int inputIndex = amc.dequeueInputBuffer(0);
if (inputIndex == -1) {
continue;
}
int sampleSize = ame.readSampleData(aInputBuffers[inputIndex], 0);
if (sampleSize == -1) break;
long presentationTime = ame.getSampleTime();
int flag = ame.getSampleFlags();
ame.advance();
amc.queueInputBuffer(inputIndex, 0, sampleSize, presentationTime, flag);
MediaCodec.BufferInfo info = new MediaCodec.BufferInfo();
int outputIndex = amc.dequeueOutputBuffer(info, 0);
if (outputIndex >= 0) {
byte[] data = new byte[info.size];
aOutputBuffers[outputIndex].get(data, 0, data.length);
aOutputBuffers[outputIndex].clear();
os.write(data);
count += data.length;
Log.e("write", "" + count);
amc.releaseOutputBuffer(outputIndex, false);
} else if (outputIndex == MediaCodec.INFO_OUTPUT_BUFFERS_CHANGED) {
aOutputBuffers = amc.getOutputBuffers();
} else if (outputIndex == MediaCodec.INFO_OUTPUT_FORMAT_CHANGED) {
}
}
os.flush();
os.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
使用videopath和audioPath创建一个新的AudioFromVideo对象并启动。