diff --git a/app/src/main/cpp/PhoneDevice.cpp b/app/src/main/cpp/PhoneDevice.cpp
index 5dc5b482..62072b95 100644
--- a/app/src/main/cpp/PhoneDevice.cpp
+++ b/app/src/main/cpp/PhoneDevice.cpp
@@ -1237,12 +1237,12 @@ bool CPhoneDevice::OnImageReady(cv::Mat& mat)
     unsigned int extime = (captureResult.exposureTime >= 1000000) ? ((unsigned int)(captureResult.exposureTime / 1000000)) : ((unsigned int)(captureResult.exposureTime / 1000));
     strcpy(extimeunit, (captureResult.exposureTime >= 1000000) ? "ms" : "ns");
     char str[128] = { 0 };
-    snprintf(str, sizeof(str), "AE=%u EXPS=%u%s(%d) ISO=%d AF=%u LDR=%d AFS=%u AES=%u SCENE=%d AWB=%u %0.1fx", captureResult.autoExposure,
+    snprintf(str, sizeof(str), "AE=%u EXPS=%u%s(%d) ISO=%d AF=%u LDR=%d(%u) AFS=%u AES=%u SCENE=%d AWB=%u %0.1fx", captureResult.autoExposure,
              extime, extimeunit, captureResult.compensation,
              captureResult.sensitibity,
              captureResult.autoFocus,
              // isnan(captureResult.FocusDistance) ? 0 : captureResult.FocusDistance,
-             GpioControl::getLightAdc(),
+             GpioControl::getLightAdc(), (unsigned int)captureResult.avgY,
              (unsigned int)captureResult.afState,
              (unsigned int)captureResult.aeState,
              captureResult.sceneMode,
diff --git a/app/src/main/cpp/camera2/ndkcamera.cpp b/app/src/main/cpp/camera2/ndkcamera.cpp
index 6259a7bd..b4c4993e 100644
--- a/app/src/main/cpp/camera2/ndkcamera.cpp
+++ b/app/src/main/cpp/camera2/ndkcamera.cpp
@@ -16,6 +16,7 @@
 
 #include <string>
 #include <thread>
+#include <numeric>
 #include <android/log.h>
 #include <opencv2/opencv.hpp>
 #include <opencv2/core/core.hpp>
@@ -738,6 +739,13 @@ void NdkCamera::onImageAvailable(AImageReader* reader)
     AImage_getPlaneData(image, 1, &u_data, &u_len);
     AImage_getPlaneData(image, 2, &v_data, &v_len);
 
+#if __cplusplus >= 201703L
+    uint64_t avgy = std::reduce(y_data, y_data + y_len, 0) / y_len;
+#else
+    uint64_t avgy = std::accumulate(y_data, y_data + y_len, 0) / y_len;
+#endif
+    mResult.avgY = avgy;
+
     if (u_data == v_data + 1 && v_data == y_data + width * height && y_pixelStride == 1 && u_pixelStride == 2 && v_pixelStride == 2 && y_rowStride == width && u_rowStride == width && v_rowStride == width)
     {
         // already nv21  :)
diff --git a/app/src/main/cpp/camera2/ndkcamera.h b/app/src/main/cpp/camera2/ndkcamera.h
index 0c943cda..10533858 100644
--- a/app/src/main/cpp/camera2/ndkcamera.h
+++ b/app/src/main/cpp/camera2/ndkcamera.h
@@ -95,6 +95,7 @@ public:
         int32_t compensation;
         uint8_t sceneMode;
         float zoomRatio;
+        uint8_t avgY;
     };
 
     NdkCamera(int32_t width, int32_t height, const CAMERA_PARAMS& params);