android JB2连拍降速原理介绍

1、HAL层
(1)alps\mediatek\platform\mt6589\hardware\camera\core\camshot\MultiShot\MultiShot.cpp sleep实现降速。
在sendCommand处理ECamShot_CMD_SET_CSHOT_SPEED。ECamShot_CMD_SET_CSHOT_SPEED定 义在alps\mediatek\platform\mt6589\hardware\camera\inc\camshot\_params.h.
MBOOL
MultiShot::
sendCommand(MINT32 cmd, MINT32 arg1, MINT32 arg2, MINT32 arg3)
{
    FUNCTION_LOG_START;
 
    MBOOL ret = MTRUE;
    //
    switch  (cmd)
    {
    case ECamShot_CMD_SET_CSHOT_SPEED:
        if(arg1 > 0)
        {
            mu4ShotSpeed = arg1;
            ret = MTRUE;
        }
        else
        {
            MY_LOGD("set invalid shot speed: %d", arg1);
            ret = MFALSE;
        }
        break;
    default:
        break;
    }
    //
 
    FUNCTION_LOG_END;
    //
    return ret;
}
 
(2)发送ECamShot_CMD_SET_CSHOT_SPEED的函数,在alps\mediatek\platform\mt6589 \hardware\camera\hal\adapter\scenario\shot\continuousshot\ContinuousShot.cpp,
bool
ContinuousShot::
onCmd_setCShotSpeed(uint32_t u4CShotSpeed)
{
    bool ret = true;
 
    Mutex::Autolock lock(mShotStopMtx);
    if(!mbShotStoped && mpMultiShot!=NULL)
    {
        MY_LOGD("set continuous shot speed: %d", u4CShotSpeed);
        ret = mpMultiShot->sendCommand(NSCamShot::ECamShot_CMD_SET_CSHOT_SPEED, u4CShotSpeed, 0, 0);
    }
 
    return ret;
}
同时在该文件的sendCommand函数处理adapter传下的eCmd_setCShotSpeed。eCmd_setCShotSpeed定义在 alps\mediatek\platform\mt6589\hardware\camera\hal\adapter\inc\scenario\shot\IShot.h
    case eCmd_setCShotSpeed:
        ret = onCmd_setCShotSpeed(arg1);
        break;
 
(3)Adapter在以下文件的函数setCShotSpeed发送eCmd_setCShotSpeed。
MtkPhotoCamAdapter.Capture.cpp (alps\mediatek\platform\mt6589\hardware\camera\hal\adapter\mtkphoto):
MtkZsdNccCamAdapter.Capture.cpp (alps\mediatek\platform\mt6589\hardware\camera\hal\adapter\mtkzsd\mtkzsdncc):
status_t
CamAdapter::
setCShotSpeed(int32_t i4CShotSpeeed)
{
    if(i4CShotSpeeed <= 0)
    {
        MY_LOGE("can not set continuous shot speed as %d fps)", i4CShotSpeeed);
        return BAD_VALUE;
    }
   
    sp<IShot> pShot = mpShot;
    if  ( pShot != 0 )
    {
        pShot->sendCommand(eCmd_setCShotSpeed, i4CShotSpeeed, 0);
    }
   
    return OK;
}
 
在以下文件sendCommad函数处理JNI送下来的CAMERA_CMD_SET_CSHOT_SPEED。
MtkCamera.h (alps\mediatek\frameworks-ext\av\include\camera):   
CAMERA_CMD_SET_CSHOT_SPEED,
 
MtkPhotoCamAdapter.cpp (alps\mediatek\platform\mt6589\hardware\camera\hal\adapter\mtkphoto): 
MtkZsdCcCamAdapter.cpp (alps\mediatek\platform\mt6589\hardware\camera\hal\adapter\mtkzsd\mtkzsdcc):
MtkZsdNccCamAdapter.cpp (alps\mediatek\platform\mt6589\hardware\camera\hal\adapter\mtkzsd\mtkzsdncc): 
    case CAMERA_CMD_SET_CSHOT_SPEED:
        return setCShotSpeed(arg1);
                  
2、JNI层
(1)android_hardware_Camera.cpp (alps\frameworks\base\core\jni):
static void android_hardware_Camera_setContinuousShotSpeed(JNIEnv *env, jobject thiz, jint value)
(2)
static JNINativeMethod camMethods[] = {
...
  { "setContinuousShotSpeed",
    "(I)V",
    (void *)android_hardware_Camera_setContinuousShotSpeed },
(3)Camera.java (alps\frameworks\base\core\java\android\hardware):  
 public native void setContinuousShotSpeed(int speed);