CameraHal: Speedup face detection start

- Currently when face detection gets enabled
  the face priority for AE and AF is getting
  configured as well. This configuration takes
  around 18 ms. on average and can delay the
  overall startup time. The optimization will
  move the algo setup away from face detection
  enablement and in to the FillBufferDone
  callback.

Bug: 5488236

Change-Id: I2b0e8df9fdead7a5d761a1efbcbf57d39e27ae3c
Signed-off-by: Emilian Peev <epeev@mm-sol.com>

3 files changed, 16 insertions, 10 deletions

diff --git a/camera/OMXCameraAdapter/OMXCameraAdapter.cpp b/camera/OMXCameraAdapter/OMXCameraAdapter.cpp
index eb77c07..a41327c 100755
--- a/camera/OMXCameraAdapter/OMXCameraAdapter.cpp
+++ b/camera/OMXCameraAdapter/OMXCameraAdapter.cpp
@@ -277,6 +277,7 @@ status_t OMXCameraAdapter::initialize(CameraProperties::Properties* caps)
     mMeasurementEnabled = false;
     mFaceDetectionRunning = false;
     mFaceDetectionPaused = false;
+    mFDSwitchAlgoPriority = false;
 
     memset(&mCameraAdapterParameters.mCameraPortParams[mCameraAdapterParameters.mImagePortIndex], 0, sizeof(OMXCameraPortParameters));
     memset(&mCameraAdapterParameters.mCameraPortParams[mCameraAdapterParameters.mPrevPortIndex], 0, sizeof(OMXCameraPortParameters));
@@ -2979,6 +2980,17 @@ OMX_ERRORTYPE OMXCameraAdapter::OMXCameraAdapterFillBufferDone(OMX_IN OMX_HANDLE
                     notifyFaceSubscribers(fdResult);
                     fdResult.clear();
                 }
+                if ( mFDSwitchAlgoPriority ) {
+
+                    //Disable region priority and enable face priority for AF
+                    setAlgoPriority(REGION_PRIORITY, FOCUS_ALGO, false);
+                    setAlgoPriority(FACE_PRIORITY, FOCUS_ALGO , true);
+
+                    //Disable Region priority and enable Face priority
+                    setAlgoPriority(REGION_PRIORITY, EXPOSURE_ALGO, false);
+                    setAlgoPriority(FACE_PRIORITY, EXPOSURE_ALGO, true);
+                    mFDSwitchAlgoPriority = false;
+                }
             }
             }
 
diff --git a/camera/OMXCameraAdapter/OMXFD.cpp b/camera/OMXCameraAdapter/OMXFD.cpp
index 55723b0..26bbd87 100644
--- a/camera/OMXCameraAdapter/OMXFD.cpp
+++ b/camera/OMXCameraAdapter/OMXFD.cpp
@@ -62,16 +62,9 @@ status_t OMXCameraAdapter::startFaceDetection()
         goto out;
     }
 
-    if ( mFaceDetectionRunning )
-        {
-        //Disable region priority and enable face priority for AF
-        setAlgoPriority(REGION_PRIORITY, FOCUS_ALGO, false);
-        setAlgoPriority(FACE_PRIORITY, FOCUS_ALGO , true);
-
-        //Disable Region priority and enable Face priority
-        setAlgoPriority(REGION_PRIORITY, EXPOSURE_ALGO, false);
-        setAlgoPriority(FACE_PRIORITY, EXPOSURE_ALGO, true);
-        }
+    if ( mFaceDetectionRunning ) {
+        mFDSwitchAlgoPriority = true;
+    }
 
     // Note: White balance will not be face prioritized, since
     // the algorithm needs full frame statistics, and not face
diff --git a/camera/inc/OMXCameraAdapter/OMXCameraAdapter.h b/camera/inc/OMXCameraAdapter/OMXCameraAdapter.h
index 6ab5ff1..0fdc770 100644
--- a/camera/inc/OMXCameraAdapter/OMXCameraAdapter.h
+++ b/camera/inc/OMXCameraAdapter/OMXCameraAdapter.h
@@ -821,6 +821,7 @@ private:
     //Face detection status
     bool mFaceDetectionRunning;
     bool mFaceDetectionPaused;
+    bool mFDSwitchAlgoPriority;
 
     camera_face_t  faceDetectionLastOutput [MAX_NUM_FACES_SUPPORTED];
     int faceDetectionNumFacesLastOutput;