声音变调的播放实现，再安卓系统音频LoudnessEnhancer扩展出来的功能. 核心处理代码来自于 http://www.surina.net/soundtouch/
##android source code:
#system\media\audio_effects\include\audio_effects\effect_loudnessenhancer.h Add: LOUDNESS_ENHANCER_PARAM_TARGET_TONE = 1
#frameworks\av\media\libeffects\loudness\EffectLoudnessEnhancer.cpp Add: LE_init: pContext->pSoundTouch->setSampleRate(sampleRate); pContext->pSoundTouch->setChannels(channels);
LELib_Create: pContext->pSoundTouch = NULL;
LE_process: pContext->pSoundTouch->putSamples(inBuffer->s16, inBuffer->frameCount); pContext->pSoundTouch->receiveSamples(pContext->tempBuff, outBuffer->frameCount);
LE_command: case EFFECT_CMD_GET_PARAM: LOUDNESS_ENHANCER_PARAM_TARGET_TONE EFFECT_CMD_SET_PARAM: LOUDNESS_ENHANCER_PARAM_TARGET_TONE
frameworks\base\media\java\android\media\audiofx\LoudnessEnhancer.java Add: public static final int PARAM_TARGET_TONE = 1;
public void setTone(int vol) throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException { checkStatus(setParameter(PARAM_TARGET_TONE, vol)); }
public int getTone() throws IllegalStateException, IllegalArgumentException, UnsupportedOperationException { int[] value = new int[1]; checkStatus(getParameter(PARAM_TARGET_TONE, value)); return value[0]; }
frameworks\base\media\jni\audioeffect\android_media_AudioEffect.cpp
complie: cd android_sourcecode/ buildenv lunch make update-api #first make
wish you luck