ImageReader: Register estimated native allocation

Estimate the native allocation and register it so it can be
accounted for during GC.

Bug: 20299272
Change-Id: I43af3058b6fe9a41e5e7e119e390ed079402c4b8

2 files changed, 70 insertions, 0 deletions

diff --git a/media/java/android/media/ImageReader.java b/media/java/android/media/ImageReader.java
index 9bd721a..c97de5d 100644
--- a/media/java/android/media/ImageReader.java
+++ b/media/java/android/media/ImageReader.java
@@ -23,6 +23,8 @@ import android.os.Looper;
 import android.os.Message;
 import android.view.Surface;
 
+import dalvik.system.VMRuntime;
+
 import java.lang.ref.WeakReference;
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
@@ -148,6 +150,13 @@ public class ImageReader implements AutoCloseable {
         nativeInit(new WeakReference<ImageReader>(this), width, height, format, maxImages);
 
         mSurface = nativeGetSurface();
+
+        // Estimate the native buffer allocation size and register it so it gets accounted for
+        // during GC. Note that this doesn't include the buffers required by the buffer queue
+        // itself and the buffers requested by the producer.
+        mEstimatedNativeAllocBytes = ImageUtils.getEstimatedNativeAllocBytes(width, height, format,
+                maxImages);
+        VMRuntime.getRuntime().registerNativeAllocation(mEstimatedNativeAllocBytes);
     }
 
     /**
@@ -467,6 +476,10 @@ public class ImageReader implements AutoCloseable {
         setOnImageAvailableListener(null, null);
         if (mSurface != null) mSurface.release();
         nativeClose();
+        if (mEstimatedNativeAllocBytes > 0) {
+            VMRuntime.getRuntime().registerNativeFree(mEstimatedNativeAllocBytes);
+            mEstimatedNativeAllocBytes = 0;
+        }
     }
 
     @Override
@@ -606,6 +619,7 @@ public class ImageReader implements AutoCloseable {
     private final int mMaxImages;
     private final int mNumPlanes;
     private final Surface mSurface;
+    private int mEstimatedNativeAllocBytes;
 
     private final Object mListenerLock = new Object();
     private OnImageAvailableListener mListener;
diff --git a/media/java/android/media/ImageUtils.java b/media/java/android/media/ImageUtils.java
index c312525..2763d1d 100644
--- a/media/java/android/media/ImageUtils.java
+++ b/media/java/android/media/ImageUtils.java
@@ -119,4 +119,60 @@ class ImageUtils {
             dstBuffer.rewind();
         }
     }
+
+    /**
+     * Return the estimated native allocation size in bytes based on width, height, format,
+     * and number of images.
+     *
+     * <p>This is a very rough estimation and should only be used for native allocation
+     * registration in VM so it can be accounted for during GC.</p>
+     *
+     * @param width The width of the images.
+     * @param height The height of the images.
+     * @param format The format of the images.
+     * @param numImages The number of the images.
+     */
+    public static int getEstimatedNativeAllocBytes(int width, int height, int format,
+            int numImages) {
+        double estimatedBytePerPixel;
+        switch (format) {
+            // 10x compression from RGB_888
+            case ImageFormat.JPEG:
+            case ImageFormat.DEPTH_POINT_CLOUD:
+                estimatedBytePerPixel = 0.3;
+                break;
+            case ImageFormat.Y8:
+                estimatedBytePerPixel = 1.0;
+                break;
+            case ImageFormat.RAW10:
+                estimatedBytePerPixel = 1.25;
+                break;
+            case ImageFormat.YV12:
+            case ImageFormat.YUV_420_888:
+            case ImageFormat.NV21:
+            case ImageFormat.PRIVATE: // A really rough estimate because the real size is unknown.
+                estimatedBytePerPixel = 1.5;
+                break;
+            case ImageFormat.NV16:
+            case PixelFormat.RGB_565:
+            case ImageFormat.YUY2:
+            case ImageFormat.Y16:
+            case ImageFormat.RAW_SENSOR:
+            case ImageFormat.DEPTH16:
+                estimatedBytePerPixel = 2.0;
+                break;
+            case PixelFormat.RGB_888:
+                estimatedBytePerPixel = 3.0;
+                break;
+            case PixelFormat.RGBA_8888:
+            case PixelFormat.RGBX_8888:
+                estimatedBytePerPixel = 4.0;
+                break;
+            default:
+                throw new UnsupportedOperationException(
+                        String.format("Invalid format specified %d", format));
+        }
+
+        return (int)(width * height * estimatedBytePerPixel * numImages);
+    }
 }