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发表于 2015-10-12 14:04:38
只看该作者
地板
private final String TAG = "MediaCodeSample";
/** 用来解码 */
private MediaCodec mMediaCodec;
/** 用来读取音频文件 */
private MediaExtractor extractor;
private MediaFormat format;
private String mime = null;
private int sampleRate = 0, channels = 0, bitrate = 0;
private long presentationTimeUs = 0, duration = 0;
public void decode(String url)
{
extractor = new MediaExtractor();
// 根据路径获取源文件
try
{
extractor.setDataSource(url);
} catch (Exception e)
{
Log.e(TAG, " 设置文件路径错误" + e.getMessage());
}
try
{
// 音频文件信息
format = extractor.getTrackFormat(0);
mime = format.getString(MediaFormat.KEY_MIME);
sampleRate = format.getInteger(MediaFormat.KEY_SAMPLE_RATE);
// 声道个数：单声道或双声道
channels = format.getInteger(MediaFormat.KEY_CHANNEL_COUNT);
// if duration is 0, we are probably playing a live stream
duration = format.getLong(MediaFormat.KEY_DURATION);
// System.out.println("歌曲总时间秒:"+duration/1000000);
bitrate = format.getInteger(MediaFormat.KEY_BIT_RATE);
} catch (Exception e)
{
Log.e(TAG, "音频文件信息读取出错：" + e.getMessage());
// 不要退出，下面进行判断
}
Log.d(TAG, "Track info: mime:" + mime + " 采样率sampleRate:" + sampleRate + " channels:" + channels + " bitrate:"
+ bitrate + " duration:" + duration);
// 检查是否为音频文件
if (format == null || !mime.startsWith("audio/"))
{
Log.e(TAG, "不是音频文件 end !");
return;
}
// 实例化一个指定类型的解码器,提供数据输出
// Instantiate an encoder supporting output data of the given mime type
mMediaCodec = MediaCodec.createDecoderByType(mime);
if (mMediaCodec == null)
{
Log.e(TAG, "创建解码器失败！");
return;
}
mMediaCodec.configure(format, null, null, 0);
mMediaCodec.start();
// 用来存放目标文件的数据
ByteBuffer[] inputBuffers = mMediaCodec.getInputBuffers();
// 解码后的数据
ByteBuffer[] outputBuffers = mMediaCodec.getOutputBuffers();
// 设置声道类型:AudioFormat.CHANNEL_OUT_MONO单声道，AudioFormat.CHANNEL_OUT_STEREO双声道
int channelConfiguration = channels == 1 ? AudioFormat.CHANNEL_OUT_MONO : AudioFormat.CHANNEL_OUT_STEREO;
Log.i(TAG, "channelConfiguration=" + channelConfiguration);
extractor.selectTrack(0);
// ==========开始解码=============
boolean sawInputEOS = false;
boolean sawOutputEOS = false;
final long kTimeOutUs = 10;
MediaCodec.BufferInfo info = new MediaCodec.BufferInfo();
while (!sawOutputEOS)
{
try
{
if (!sawInputEOS)
{
int inputBufIndex = mMediaCodec.dequeueInputBuffer(kTimeOutUs);
if (inputBufIndex >= 0)
{
ByteBuffer dstBuf = inputBuffers[inputBufIndex];
int sampleSize = extractor.readSampleData(dstBuf, 0);
if (sampleSize < 0)
{
Log.d(TAG, "saw input EOS. Stopping playback");
sawInputEOS = true;
sampleSize = 0;
} else
{
presentationTimeUs = extractor.getSampleTime();
}
mMediaCodec.queueInputBuffer(inputBufIndex, 0, sampleSize, presentationTimeUs,
sawInputEOS ? MediaCodec.BUFFER_FLAG_END_OF_STREAM : 0);
if (!sawInputEOS)
{
extractor.advance();
}
} else
{
Log.e(TAG, "inputBufIndex " + inputBufIndex);
}
} // !sawInputEOS
// decode to PCM and push it to the AudioTrack player
int res = mMediaCodec.dequeueOutputBuffer(info, kTimeOutUs);
if (res >= 0)
{
int outputBufIndex = res;
ByteBuffer buf = outputBuffers[outputBufIndex];
final byte[] chunk = new byte[info.size];
buf.get(chunk);
buf.clear();
if (chunk.length > 0)
{
// chunk解码后的音频流
// TODO:处理...
}
mMediaCodec.releaseOutputBuffer(outputBufIndex, false);
if ((info.flags & MediaCodec.BUFFER_FLAG_END_OF_STREAM) != 0)
{
Log.d(TAG, "saw output EOS.");
sawOutputEOS = true;
}
} else if (res == MediaCodec.INFO_OUTPUT_BUFFERS_CHANGED)
{
outputBuffers = mMediaCodec.getOutputBuffers();
Log.w(TAG, "[AudioDecoder]output buffers have changed.");
} else if (res == MediaCodec.INFO_OUTPUT_FORMAT_CHANGED)
{
MediaFormat oformat = mMediaCodec.getOutputFormat();
Log.w(TAG, "[AudioDecoder]output format has changed to " + oformat);
} else
{
Log.w(TAG, "[AudioDecoder] dequeueOutputBuffer returned " + res);
}
} catch (RuntimeException e)
{
Log.e(TAG, "[decodeMP3] error:" + e.getMessage());
}
}
// =================================================================================
if (mMediaCodec != null)
{
mMediaCodec.stop();
mMediaCodec.release();
mMediaCodec = null;
}
if (extractor != null)
{
extractor.release();
extractor = null;
}
// clear source and the other globals
duration = 0;
mime = null;
sampleRate = 0;
channels = 0;
bitrate = 0;
presentationTimeUs = 0;
duration = 0;
}
你们官方是基于mediacodec做的么？ 为何你们那个实时性那么好，一点都没有卡顿！ 网上的硬解码代码在3288上跑很卡！ |
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