Auto Exposure:

  - Filter results down to the three best.
  - Changing exposure based on distance to the target or at random.
  - Plumb exposure through the debug framework.
  - Refactor into target finder.

Change-Id: Ia083f56859938bf0825472fd15d248c545f6f2fc
diff --git a/aos/vision/image/reader.h b/aos/vision/image/reader.h
index adb3a3c..25fc0bd 100644
--- a/aos/vision/image/reader.h
+++ b/aos/vision/image/reader.h
@@ -32,10 +32,11 @@
   }
   int fd() { return fd_; }
 
+  bool SetCameraControl(uint32_t id, const char *name, int value);
+
  private:
   void QueueBuffer(v4l2_buffer *buf);
   void InitMMap();
-  bool SetCameraControl(uint32_t id, const char *name, int value);
   void Init();
   void Start();
   void MMapBuffers();