1 files changed, 52 insertions, 0 deletions
diff --git a/tests/Camera2Tests/SmartCamera/SimpleCamera/jni/brightness.cpp b/tests/Camera2Tests/SmartCamera/SimpleCamera/jni/brightness.cpp
new file mode 100644
index 0000000..998fd4c
--- /dev/null
+++ b/tests/Camera2Tests/SmartCamera/SimpleCamera/jni/brightness.cpp
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// Native function to extract brightness from image (handed down as ByteBuffer).
+
+#include "brightness.h"
+
+#include <math.h>
+#include <string.h>
+#include <jni.h>
+#include <unistd.h>
+#include <android/log.h>
+
+jfloat
+Java_androidx_media_filterfw_samples_simplecamera_AvgBrightnessFilter_brightnessOperator(
+    JNIEnv* env, jclass clazz, jint width, jint height, jobject imageBuffer) {
+
+    if (imageBuffer == 0) {
+        return 0.0f;
+    }
+    float pixelTotals[] = { 0.0f, 0.0f, 0.0f };
+    const int numPixels = width * height;
+    unsigned char* srcPtr = static_cast<unsigned char*>(env->GetDirectBufferAddress(imageBuffer));
+    for (int i = 0; i < numPixels; i++) {
+        pixelTotals[0] += *(srcPtr + 4 * i);
+        pixelTotals[1] += *(srcPtr + 4 * i + 1);
+        pixelTotals[2] += *(srcPtr + 4 * i + 2);
+    }
+    float avgPixels[] = { 0.0f, 0.0f, 0.0f };
+
+    avgPixels[0] = pixelTotals[0] / numPixels;
+    avgPixels[1] = pixelTotals[1] / numPixels;
+    avgPixels[2] = pixelTotals[2] / numPixels;
+    float returnValue = sqrt(0.241f * avgPixels[0] * avgPixels[0] +
+                            0.691f * avgPixels[1] * avgPixels[1] +
+                            0.068f * avgPixels[2] * avgPixels[2]);
+
+    return returnValue / 255;
+}