表題通り、MediaExtractorを使用しない場合のMediaCodecのデコード方法がわかりません。

自分が探した限りではMediaCodecによるデコードのサンプルはほとんどがMediaExtractorを使用したものばかりでした。MediaExtractorを使用したくない理由として再生をしながら メタデータ(icy-meta, Shoutcast)、MP3 Rawバイナリを操作したいと考えているからです。

MediaExtractorをもちいたデコードのサンプルを元にFileInputStreamを使用したコードを書いてみました。エラーが起きてまともにデコードできません。

package com.test;

import android.app.Activity;
import android.media.AudioFormat;
import android.media.AudioManager;
import android.media.AudioTrack;
import android.media.MediaCodec;
import android.media.MediaCodec.BufferInfo;

import android.media.MediaFormat;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.nio.ByteBuffer;

import com.test.R;

public class AndroidTestActivity extends Activity {

    private static final String TAG = "TAG";

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

        new Thread() {
            @Override
            public void run() {
                try {
                    process();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }.start();
    }

    private synchronized void process() throws IOException {
        File inputFile = new File(Environment.getExternalStorageDirectory().getPath() + "/download/music/test.mp3");
        FileInputStream fis = new FileInputStream(inputFile);        

        MediaFormat format = MediaFormat.createAudioFormat("audio/mpeg", 44100,2);
        String mime = format.getString(MediaFormat.KEY_MIME);
        //int sampleRate = format.getInteger(MediaFormat.KEY_SAMPLE_RATE);

        MediaCodec codec = MediaCodec.createDecoderByType(mime);
        codec.configure(format, null , null , 0);
        codec.start();

        ByteBuffer[] codecInputBuffers = codec.getInputBuffers();
        ByteBuffer[] codecOutputBuffers = codec.getOutputBuffers();

        AudioTrack track = new AudioTrack(AudioManager.STREAM_MUSIC,
                format.getInteger(MediaFormat.KEY_SAMPLE_RATE),
                AudioFormat.CHANNEL_OUT_STEREO, AudioFormat.ENCODING_PCM_16BIT,
                8000, AudioTrack.MODE_STREAM);
        track.play();

        BufferInfo info = new BufferInfo();
        boolean inputEos = false;
        boolean outputEos = false;
        long timeoutUs = 1000;

        byte[] tempBuffer = new byte[8192];

        while (!outputEos) {
            if (!inputEos) {
                int inputBufIndex = codec.dequeueInputBuffer(timeoutUs);
                if (inputBufIndex >= 0) {
                    ByteBuffer buf = codecInputBuffers[inputBufIndex];

                    int bytesRead = fis.read(tempBuffer, 0, buf.limit());

                    long presentationTimeUs = 0;
                    if (bytesRead < 0) {
                        inputEos = true;
                        bytesRead = 0;
                    } else {
                        presentationTimeUs = System.nanoTime();
                    }

                    codec.queueInputBuffer(inputBufIndex, 0, bytesRead, presentationTimeUs,
                            inputEos ? MediaCodec.BUFFER_FLAG_END_OF_STREAM : 0);
                }
            }

            int res = codec.dequeueOutputBuffer(info, timeoutUs);

            if (res >= 0) {
                int outputBufIndex = res;

                ByteBuffer buf = codecOutputBuffers[outputBufIndex];
                byte[] dst = new byte[info.size];
                int oldPosition = buf.position();

                buf.get(dst);
                buf.position(oldPosition);

                //Play music
                track.write(dst, 0, dst.length);

                codec.releaseOutputBuffer(outputBufIndex, false);

                if ((info.flags & MediaCodec.BUFFER_FLAG_END_OF_STREAM) != 0) {
                    Log.d(TAG, "output eos.");
                    outputEos = true;
                }
            } else if (res == MediaCodec.INFO_OUTPUT_BUFFERS_CHANGED) {
                Log.d(TAG, "output buffer changed.");
                codecOutputBuffers = codec.getOutputBuffers();
            } else if (res == MediaCodec.INFO_OUTPUT_FORMAT_CHANGED) {
                MediaFormat f = codec.getOutputFormat();
                Log.d(TAG, "output format changed. " + f);
                //track.setPlaybackRate(f.getInteger(MediaFormat.KEY_SAMPLE_RATE));
            }
        }

        Log.d(TAG, "complete stop!");
        fis.close();
        codec.stop();
        codec.release();
    }
}

以下実行時のエラー

01-20 00:57:22.271: I/OMXClient(2626): Using client-side OMX mux.
01-20 00:57:22.276: E/SEC_COMP_REGS(2626): .
01-20 00:57:22.276: E/SEC_COMP_REGS(2626): ..
01-20 00:57:22.276: E/SEC_COMP_REGS(2626): libOMX.SEC.AVC.Decoder.so
01-20 00:57:22.276: E/SEC_COMP_REGS(2626): Path & libName : /system/lib/omx/libOMX.SEC.AVC.Decoder.so
01-20 00:57:22.276: E/SEC_COMP_REGS(2626): libOMX.SEC.AVC.Encoder.so
01-20 00:57:22.276: E/SEC_COMP_REGS(2626): Path & libName : /system/lib/omx/libOMX.SEC.AVC.Encoder.so
01-20 00:57:22.281: E/SEC_COMP_REGS(2626): libOMX.SEC.M4V.Decoder.so
01-20 00:57:22.281: E/SEC_COMP_REGS(2626): Path & libName : /system/lib/omx/libOMX.SEC.M4V.Decoder.so
01-20 00:57:22.281: E/SEC_COMP_REGS(2626): libOMX.SEC.M4V.Encoder.so
01-20 00:57:22.291: E/SEC_COMP_REGS(2626): Path & libName : /system/lib/omx/libOMX.SEC.M4V.Encoder.so
01-20 00:57:22.291: E/SEC_COMP_REGS(2626): libOMX.SEC.WMV.Decoder.so
01-20 00:57:22.291: E/SEC_COMP_REGS(2626): Path & libName : /system/lib/omx/libOMX.SEC.WMV.Decoder.so
01-20 00:57:22.311: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:22.321: D/TAG(2626): output format changed. {sample-rate=44100, channel-count=2, what=1869968451, mime=audio/raw}
01-20 00:57:22.331: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:22.341: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:22.351: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:22.396: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:22.436: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:22.481: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:22.486: D/libEGL(2626): loaded /system/lib/egl/libEGL_mali.so
01-20 00:57:22.491: D/libEGL(2626): loaded /system/lib/egl/libGLESv1_CM_mali.so
01-20 00:57:22.496: D/libEGL(2626): loaded /system/lib/egl/libGLESv2_mali.so
01-20 00:57:22.506: E/(2626): Device driver API match
01-20 00:57:22.506: E/(2626): Device driver API version: 23
01-20 00:57:22.506: E/(2626): User space API version: 23 
01-20 00:57:22.506: E/(2626): mali: REVISION=Linux-r3p2-01rel3 BUILD_DATE=Wed Oct  9 21:05:57 KST 2013 
01-20 00:57:22.526: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:22.536: D/OpenGLRenderer(2626): Enabling debug mode 0
01-20 00:57:22.576: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:22.621: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:22.626: I/ActivityManager(2626): Timeline: Activity_idle id: android.os.BinderProxy@424d6780 time:611732103
01-20 00:57:22.666: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:22.716: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:22.811: E/SoftMP3(2626): mp3 decoder returned error 12
...以下略...
01-20 00:57:29.171: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:29.221: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:29.266: E/SoftMP3(2626): mp3 decoder returned error 12
01-20 00:57:29.401: D/TAG(2626): output eos.
01-20 00:57:29.401: D/TAG(2626): complete stop!
01-20 00:57:29.411: I/OMXNodeInstance(2626): OMX_FreeBuffer for buffer header 0x524cc9d8 successful
01-20 00:57:29.411: I/OMXNodeInstance(2626): OMX_FreeBuffer for buffer header 0x524cc8d8 successful
01-20 00:57:29.411: I/OMXNodeInstance(2626): OMX_FreeBuffer for buffer header 0x524cc7c0 successful
01-20 00:57:29.416: I/OMXNodeInstance(2626): OMX_FreeBuffer for buffer header 0x524cad28 successful
01-20 00:57:29.416: I/OMXNodeInstance(2626): OMX_FreeBuffer for buffer header 0x524cd018 successful
01-20 00:57:29.421: I/OMXNodeInstance(2626): OMX_FreeBuffer for buffer header 0x524ccf48 successful
01-20 00:57:29.421: I/OMXNodeInstance(2626): OMX_FreeBuffer for buffer header 0x524cce30 successful
01-20 00:57:29.426: I/OMXNodeInstance(2626): OMX_FreeBuffer for buffer header 0x524cccb8 successful