ximalayadownloader&x2mdecoder

ximalayadownloader是一款可以帮助用户下载喜马拉雅音频内容的工具。喜马拉雅是一个非常受欢迎的音频平台，上面有各种各样的音乐、有声书、广播剧等内容。但是，由于各种原因，有时用户可能希望将这些音频内容下载下来，以便在没有网络的情况下也能够随时听到这些内容。

而ximalayadownloader就是为了满足这个需求而创建的。它可以与喜马拉雅平台连接，帮助用户快速、简便地下载他们喜欢的音频内容。用户只需要将目标音频的链接复制到ximalayadownloader中，然后选择下载的格式和保存的位置，就可以开始下载了。

ximalayadownloader拥有强大的下载功能。它可以同时下载多个音频，并且支持下载高质量音频。用户可以根据自己的需求选择下载mp3、aac、m4a等常见音频格式。同时，ximalayadownloader还支持断点续传功能，即使在下载过程中遇到问题或中断，用户也可以随时恢复下载，而无需重新下载。

ximalayadownloader还具有简洁、直观的界面设计，用户可以轻松上手，即使是不太懂电脑操作的人也能够使用。而且，ximalayadownloader免费提供给用户使用，无需付费。这使得它成为喜马拉雅用户中下载音频的首选工具之一。

总之，ximalayadownloader可以帮助用户快速、方便地下载喜马拉雅平台上的音频内容，并且具有强大的下载功能和简洁的界面设计。无论是在没有网络的情况下还是为了方便随时收听，ximalayadownloader都是喜马拉雅用户的理想选择。

相关问题

android下使用FFMpeg的VAAPI播放视频并显示到SurfaceView的代码

很抱歉，Android系统不支持 VAAPI，它是用于 Linux 等操作系统的视频加速 API。在 Android 中，可以使用硬件加速来加速视频播放，例如使用 MediaCodec 和 SurfaceView 进行视频解码和渲染。下面是一个简单的示例代码：

import android.media.MediaCodec;
import android.media.MediaExtractor;
import android.media.MediaFormat;
import android.media.MediaCodec.BufferInfo;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import java.io.IOException;
import java.nio.ByteBuffer;

public class VideoPlayer implements SurfaceHolder.Callback {
    private SurfaceView mSurfaceView;
    private Surface mSurface;
    private MediaExtractor mExtractor;
    private MediaCodec mDecoder;
    private boolean mIsPlaying;

    public VideoPlayer(SurfaceView surfaceView) {
        mSurfaceView = surfaceView;
        mSurfaceView.getHolder().addCallback(this);
    }

    public void play(String videoPath) throws IOException {
        mExtractor = new MediaExtractor();
        mExtractor.setDataSource(videoPath);
        int trackIndex = selectTrack(mExtractor);
        mExtractor.selectTrack(trackIndex);
        MediaFormat mediaFormat = mExtractor.getTrackFormat(trackIndex);
        String mime = mediaFormat.getString(MediaFormat.KEY_MIME);
        mDecoder = MediaCodec.createDecoderByType(mime);
        mDecoder.configure(mediaFormat, mSurface, null, 0);
        mDecoder.start();

        ByteBuffer[] inputBuffers = mDecoder.getInputBuffers();
        ByteBuffer[] outputBuffers = mDecoder.getOutputBuffers();
        BufferInfo bufferInfo = new BufferInfo();

        mIsPlaying = true;
        while (mIsPlaying) {
            int inputBufferIndex = mDecoder.dequeueInputBuffer(10000);
            if (inputBufferIndex >= 0) {
                ByteBuffer inputBuffer = inputBuffers[inputBufferIndex];
                int sampleSize = mExtractor.readSampleData(inputBuffer, 0);
                if (sampleSize < 0) {
                    mDecoder.queueInputBuffer(inputBufferIndex, 0, 0, 0, MediaCodec.BUFFER_FLAG_END_OF_STREAM);
                    mIsPlaying = false;
                } else {
                    long presentationTimeUs = mExtractor.getSampleTime();
                    mDecoder.queueInputBuffer(inputBufferIndex, 0, sampleSize, presentationTimeUs, 0);
                    mExtractor.advance();
                }
            }

            int outputBufferIndex = mDecoder.dequeueOutputBuffer(bufferInfo, 10000);
            switch (outputBufferIndex) {
                case MediaCodec.INFO_OUTPUT_BUFFERS_CHANGED:
                    outputBuffers = mDecoder.getOutputBuffers();
                    break;
                case MediaCodec.INFO_OUTPUT_FORMAT_CHANGED:
                    // do nothing
                    break;
                case MediaCodec.INFO_TRY_AGAIN_LATER:
                    // do nothing
                    break;
                default:
                    ByteBuffer outputBuffer = outputBuffers[outputBufferIndex];
                    mDecoder.releaseOutputBuffer(outputBufferIndex, true);
                    break;
            }
        }

        mDecoder.stop();
        mDecoder.release();
        mExtractor.release();
    }

    private int selectTrack(MediaExtractor extractor) {
        int numTracks = extractor.getTrackCount();
        for (int i = 0; i < numTracks; i++) {
            MediaFormat format = extractor.getTrackFormat(i);
            String mime = format.getString(MediaFormat.KEY_MIME);
            if (mime.startsWith("video/")) {
                return i;
            }
        }
        return -1;
    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        mSurface = holder.getSurface();
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
        // do nothing
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        mSurface = null;
    }
}

使用示例：

VideoPlayer player = new VideoPlayer(surfaceView);
try {
    player.play(videoPath);
} catch (IOException e) {
    e.printStackTrace();
}

帮我编写一个解码aac数据的安卓代码

好的，下面是一个基本的解码AAC数据的Android代码示例：

import android.media.AudioFormat;
import android.media.AudioManager;
import android.media.AudioTrack;
import android.media.MediaCodec;
import android.media.MediaExtractor;
import android.media.MediaFormat;
import android.os.Bundle;
import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.nio.ByteBuffer;

public class MainActivity extends AppCompatActivity {

    private static final String TAG = "MainActivity";
    private Button mButton;
    private MediaExtractor mExtractor;
    private MediaCodec mDecoder;
    private ByteBuffer[] mInputBuffers;
    private ByteBuffer[] mOutputBuffers;
    private int mInputBufferIndex;
    private int mOutputBufferIndex;
    private MediaCodec.BufferInfo mBufferInfo;
    private AudioTrack mAudioTrack;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mButton = findViewById(R.id.button);
        mButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startDecode();
            }
        });
    }

    private void startDecode() {
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    File file = new File(Environment.getExternalStorageDirectory(), "test.aac");
                    FileInputStream fis = new FileInputStream(file);

                    mExtractor = new MediaExtractor();
                    mExtractor.setDataSource(fis.getFD());

                    int audioTrackIndex = -1;
                    int trackCount = mExtractor.getTrackCount();
                    for (int i = 0; i < trackCount; i++) {
                        MediaFormat format = mExtractor.getTrackFormat(i);
                        String mime = format.getString(MediaFormat.KEY_MIME);
                        Log.d(TAG, "mime type: " + mime);

                        if (mime.startsWith("audio/")) {
                            mExtractor.selectTrack(i);
                            mDecoder = MediaCodec.createDecoderByType(mime);
                            mDecoder.configure(format, null, null, 0);
                            mDecoder.start();

                            mInputBuffers = mDecoder.getInputBuffers();
                            mOutputBuffers = mDecoder.getOutputBuffers();
                            mBufferInfo = new MediaCodec.BufferInfo();

                            int sampleRate = format.getInteger(MediaFormat.KEY_SAMPLE_RATE);
                            int channelCount = format.getInteger(MediaFormat.KEY_CHANNEL_COUNT);
                            int audioFormat = AudioFormat.ENCODING_PCM_16BIT;
                            int minBufferSize = AudioTrack.getMinBufferSize(sampleRate, channelCount, audioFormat);
                            mAudioTrack = new AudioTrack(AudioManager.STREAM_MUSIC, sampleRate, channelCount, audioFormat, minBufferSize, AudioTrack.MODE_STREAM);
                            mAudioTrack.play();

                            audioTrackIndex = i;
                            break;
                        }
                    }

                    if (audioTrackIndex == -1) {
                        Log.e(TAG, "no audio track found");
                        return;
                    }

                    while (true) {
                        mInputBufferIndex = mDecoder.dequeueInputBuffer(10000);
                        if (mInputBufferIndex < 0) {
                            continue;
                        }

                        ByteBuffer inputBuffer = mInputBuffers[mInputBufferIndex];
                        inputBuffer.clear();

                        int sampleSize = mExtractor.readSampleData(inputBuffer, 0);
                        if (sampleSize < 0) {
                            mDecoder.queueInputBuffer(mInputBufferIndex, 0, 0, 0, MediaCodec.BUFFER_FLAG_END_OF_STREAM);
                            break;
                        }

                        mDecoder.queueInputBuffer(mInputBufferIndex, 0, sampleSize, mExtractor.getSampleTime(), 0);
                        mExtractor.advance();

                        mOutputBufferIndex = mDecoder.dequeueOutputBuffer(mBufferInfo, 10000);
                        while (mOutputBufferIndex >= 0) {
                            ByteBuffer outputBuffer = mOutputBuffers[mOutputBufferIndex];
                            byte[] chunk = new byte[mBufferInfo.size];
                            outputBuffer.get(chunk);
                            outputBuffer.clear();

                            mAudioTrack.write(chunk, 0, chunk.length);

                            mDecoder.releaseOutputBuffer(mOutputBufferIndex, false);
                            mOutputBufferIndex = mDecoder.dequeueOutputBuffer(mBufferInfo, 0);
                        }

                        if ((mBufferInfo.flags & MediaCodec.BUFFER_FLAG_END_OF_STREAM) != 0) {
                            Log.d(TAG, "end of stream reached");
                            break;
                        }
                    }

                    mAudioTrack.stop();
                    mAudioTrack.release();
                    mDecoder.stop();
                    mDecoder.release();
                    mExtractor.release();
                    fis.close();

                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }).start();
    }
}

这个代码示例使用了Android提供的MediaExtractor和MediaCodec来解码AAC文件，然后使用AudioTrack播放解码后的音频数据。请注意，在实际使用中你可能需要根据自己的需求进行修改和优化。