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Diffstat (limited to 'core/java/android/speech/tts/PlaybackSynthesisRequest.java')
| -rw-r--r-- | core/java/android/speech/tts/PlaybackSynthesisRequest.java | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/core/java/android/speech/tts/PlaybackSynthesisRequest.java b/core/java/android/speech/tts/PlaybackSynthesisRequest.java new file mode 100644 index 0000000..15a4ee9 --- /dev/null +++ b/core/java/android/speech/tts/PlaybackSynthesisRequest.java @@ -0,0 +1,197 @@ +/* + * Copyright (C) 2011 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); you may not + * use this file except in compliance with the License. You may obtain a copy of + * the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the + * License for the specific language governing permissions and limitations under + * the License. + */ +package android.speech.tts; + +import android.media.AudioFormat; +import android.media.AudioTrack; +import android.util.Log; + +/** + * Speech synthesis request that plays the audio as it is received. + */ +class PlaybackSynthesisRequest extends SynthesisRequest { + + private static final String TAG = "PlaybackSynthesisRequest"; + private static final boolean DBG = false; + + private static final int MIN_AUDIO_BUFFER_SIZE = 8192; + + /** + * Audio stream type. Must be one of the STREAM_ contants defined in + * {@link android.media.AudioManager}. + */ + private final int mStreamType; + + /** + * Volume, in the range [0.0f, 1.0f]. The default value is + * {@link TextToSpeech.Engine#DEFAULT_VOLUME} (1.0f). + */ + private final float mVolume; + + /** + * Left/right position of the audio, in the range [-1.0f, 1.0f]. + * The default value is {@link TextToSpeech.Engine#DEFAULT_PAN} (0.0f). + */ + private final float mPan; + + private final Object mStateLock = new Object(); + private AudioTrack mAudioTrack = null; + private boolean mStopped = false; + + PlaybackSynthesisRequest(String text, int streamType, float volume, float pan) { + super(text); + mStreamType = streamType; + mVolume = volume; + mPan = pan; + } + + @Override + void stop() { + if (DBG) Log.d(TAG, "stop()"); + synchronized (mStateLock) { + mStopped = true; + cleanUp(); + } + } + + private void cleanUp() { + if (DBG) Log.d(TAG, "cleanUp()"); + if (mAudioTrack != null) { + mAudioTrack.flush(); + mAudioTrack.stop(); + // TODO: do we need to wait for playback to finish before releasing? + mAudioTrack.release(); + mAudioTrack = null; + } + } + + // TODO: add a thread that writes to the AudioTrack? + @Override + public int start(int sampleRateInHz, int audioFormat, int channelCount) { + if (DBG) { + Log.d(TAG, "start(" + sampleRateInHz + "," + audioFormat + + "," + channelCount + ")"); + } + + int channelConfig; + if (channelCount == 1) { + channelConfig = AudioFormat.CHANNEL_OUT_MONO; + } else if (channelCount == 2){ + channelConfig = AudioFormat.CHANNEL_OUT_STEREO; + } else { + Log.e(TAG, "Unsupported number of channels: " + channelCount); + return TextToSpeech.ERROR; + } + + int minBufferSizeInBytes + = AudioTrack.getMinBufferSize(sampleRateInHz, channelConfig, audioFormat); + int bufferSizeInBytes = Math.max(MIN_AUDIO_BUFFER_SIZE, minBufferSizeInBytes); + + synchronized (mStateLock) { + if (mStopped) { + if (DBG) Log.d(TAG, "Request has been aborted."); + return TextToSpeech.ERROR; + } + if (mAudioTrack != null) { + Log.e(TAG, "start() called twice"); + cleanUp(); + return TextToSpeech.ERROR; + } + + mAudioTrack = new AudioTrack(mStreamType, sampleRateInHz, channelConfig, audioFormat, + bufferSizeInBytes, AudioTrack.MODE_STREAM); + if (mAudioTrack.getState() != AudioTrack.STATE_INITIALIZED) { + cleanUp(); + return TextToSpeech.ERROR; + } + + setupVolume(); + } + + return TextToSpeech.SUCCESS; + } + + private void setupVolume() { + float vol = clip(mVolume, 0.0f, 1.0f); + float panning = clip(mPan, -1.0f, 1.0f); + float volLeft = vol; + float volRight = vol; + if (panning > 0.0f) { + volLeft *= (1.0f - panning); + } else if (panning < 0.0f) { + volRight *= (1.0f + panning); + } + if (DBG) Log.d(TAG, "volLeft=" + volLeft + ",volRight=" + volRight); + if (mAudioTrack.setStereoVolume(volLeft, volRight) != AudioTrack.SUCCESS) { + Log.e(TAG, "Failed to set volume"); + } + } + + private float clip(float value, float min, float max) { + return value > max ? max : (value < min ? min : value); + } + + @Override + public int audioAvailable(byte[] buffer, int offset, int length) { + if (DBG) { + Log.d(TAG, "audioAvailable(byte[" + buffer.length + "]," + + offset + "," + length + "), thread ID=" + android.os.Process.myTid()); + } + synchronized (mStateLock) { + if (mStopped) { + if (DBG) Log.d(TAG, "Request has been aborted."); + return TextToSpeech.ERROR; + } + if (mAudioTrack == null) { + Log.e(TAG, "audioAvailable(): Not started"); + return TextToSpeech.ERROR; + } + int playState = mAudioTrack.getPlayState(); + if (playState == AudioTrack.PLAYSTATE_STOPPED) { + if (DBG) Log.d(TAG, "AudioTrack stopped, restarting"); + mAudioTrack.play(); + } + // TODO: loop until all data is written? + if (DBG) Log.d(TAG, "AudioTrack.write()"); + int count = mAudioTrack.write(buffer, offset, length); + if (DBG) Log.d(TAG, "AudioTrack.write() returned " + count); + if (count < 0) { + Log.e(TAG, "Writing to AudioTrack failed: " + count); + cleanUp(); + return TextToSpeech.ERROR; + } else { + return TextToSpeech.SUCCESS; + } + } + } + + @Override + public int done() { + if (DBG) Log.d(TAG, "done()"); + synchronized (mStateLock) { + if (mStopped) { + if (DBG) Log.d(TAG, "Request has been aborted."); + return TextToSpeech.ERROR; + } + if (mAudioTrack == null) { + Log.e(TAG, "done(): Not started"); + return TextToSpeech.ERROR; + } + cleanUp(); + } + return TextToSpeech.SUCCESS; + } +}
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