实现预览到静态抓拍的主动切换

app/src/main/cpp/camera2/ndkcamera.cpp

@@ -282,6 +282,7 @@ NdkCamera::NdkCamera(int32_t width, int32_t height, const NdkCamera::CAMERA_PARA
 	mLdr = ~0;
 	mFinalLdr = 0;
 	mFinalOutputFormat = AIMAGE_FORMAT_YUV_420_888;
+    m_delayFrames = 0;
 }
 
 NdkCamera::~NdkCamera()
@@ -813,7 +814,8 @@ NdkCamera::CaptureRequest* NdkCamera::CreateRequest(bool isPreviewRequest)
 	uint8_t ctrlMode = ACAMERA_CONTROL_MODE_AUTO;
 	status = ACaptureRequest_setEntry_u8(request->request, ACAMERA_CONTROL_MODE, 1, &ctrlMode);
 
-	uint8_t captureIntent = GetCaptureIntent((ACameraDevice_request_template)m_params.requestTemplate);
+	// uint8_t captureIntent = GetCaptureIntent((ACameraDevice_request_template)m_params.requestTemplate);
+    uint8_t captureIntent = ACAMERA_CONTROL_CAPTURE_INTENT_PREVIEW;
 	status = ACaptureRequest_setEntry_u8(request->request, ACAMERA_CONTROL_CAPTURE_INTENT, 1, &captureIntent);
 
 	uint8_t flashMode = ACAMERA_FLASH_MODE_OFF;
@@ -1468,6 +1470,29 @@ void NdkCamera::onCaptureProgressed(ACameraCaptureSession* session, ACaptureRequ
 
 void NdkCamera::onCaptureCompleted(ACameraCaptureSession* session, ACaptureRequest* request, const ACameraMetadata* result)
 {
+    camera_status_t status = ACAMERA_ERROR_BASE;
+    m_delayFrames++;
+
+    if (m_delayFrames <= 4)
+    {
+        if (m_delayFrames == 4)
+        {
+            uint8_t captureIntent = GetCaptureIntent((ACameraDevice_request_template)m_params.requestTemplate);
+            if (captureIntent != ACAMERA_CONTROL_CAPTURE_INTENT_PREVIEW)
+            {
+                status = ACaptureRequest_setEntry_u8(request, ACAMERA_CONTROL_CAPTURE_INTENT, 1, &captureIntent);
+
+                if (m_params.burstRawCapture == 2 || m_params.burstRawCapture == 3)
+                {
+                    int32_t stillCaptureHint = 1;
+                    status = ACaptureRequest_setEntry_i32(request, MTK_CONTROL_CAPTURE_HINT_FOR_ISP_TUNING, 1, &stillCaptureHint);
+                }
+            }
+            mCaptureTriggered = true;
+        }
+        return;
+    }
+
     m_locker.lock();
     int64_t minTs = m_minTimestamp;
     m_locker.unlock();
@@ -1488,7 +1513,7 @@ void NdkCamera::onCaptureCompleted(ACameraCaptureSession* session, ACaptureReque
 	CaptureRequest* pCaptureRequest = reinterpret_cast<CaptureRequest *>(context);
 
     bool readyForCapture = true;
-    camera_status_t status = ACAMERA_ERROR_BASE;
+
     uint64_t ts = GetMicroTimeStamp();
 
     uint8_t aeState = ACAMERA_CONTROL_AE_STATE_INACTIVE;
@@ -1688,7 +1713,6 @@ void NdkCamera::onCaptureCompleted(ACameraCaptureSession* session, ACaptureReque
 			}
 #endif
 
-        mCaptureTriggered = true;
     }
 }
 
@@ -2264,6 +2288,4 @@ void NdkCamera::SetupMFNR(ACameraMetadata* characteristics, ACaptureRequest* req
             ALOGE("Failed to set MTK_CONTROL_AE_EXPOSURE_COMPENSATION, status: %d", status);
         }
     }
-
-
 }

app/src/main/cpp/camera2/ndkcamera.h

@@ -246,6 +246,7 @@ protected:
 
     CAPTURE_RESULT mResult;
     uint64_t m_startTime;
+    uint64_t m_delayFrames;
 
 protected: