Added minor code and README corrections

Author: Anastasia

DNN-OpenCV-Classification-with-Java/DnnOpenCV.java

@@ -27,6 +27,8 @@ public class DnnOpenCV {
     private static final String IMAGENET_CLASSES = "imagenet_classes.txt";
     private static final String MODEL_PATH = "models/pytorch_mobilenet.onnx";
 
+    private static final Scalar MEAN = new Scalar(0.485, 0.456, 0.406);
+    private static final Scalar STD = new Scalar(0.229, 0.224, 0.225);
 
     public static ArrayList<String> getImgLabels(String imgLabelsFilePath) throws IOException {
         ArrayList<String> imgLabels;
@@ -49,10 +51,6 @@ public static Mat centerCrop(Mat inputImage) {
     }
 
     public static Mat getPreprocessedImage(String imagePath) {
-        // define mean and standard deviation
-        Scalar mean = new Scalar(0.485, 0.456, 0.406);
-        Scalar std = new Scalar(0.229, 0.224, 0.225);
-
         // get the image from the internal resource folder
         Mat image = Imgcodecs.imread(imagePath);
 
@@ -73,13 +71,13 @@ public static Mat getPreprocessedImage(String imagePath) {
                 imgFloat,
                 1.0, /* default scalefactor */
                 new Size(TARGET_IMG_WIDTH, TARGET_IMG_HEIGHT), /* target size */
-                mean,  /* mean */
+                MEAN,  /* mean */
                 true, /* swapRB */
                 false /* crop */
         );
 
         // divide on std
-        Core.divide(blob, std, blob);
+        Core.divide(blob, STD, blob);
 
         return blob;
     }

DNN-OpenCV-Classification-with-Java/README.md

@@ -134,26 +134,19 @@ sudo ldconfig
 
 which creates the necessary links and cache to our freshly built shared library.
 
-Rename the created Python3 bindings for OpenCV to `cv2.so`:
+Put ``lib/python3/cv2.cpython-37m-x86_64-linux-gnu.so`` into the virtual environment installed packages:
 
 ```bash
-mv lib/python3/cv2.cpython-37m-x86_64-linux-gnu.so cv2.so
+cp lib/python3/cv2.cpython-36m-x86_64-linux-gnu.so ~/env/lib/python3.7/site-packages/cv2.so
 ```
 
-Create a symlink of our OpenCV `cv2.so` into the virtual environment installed packages:
-
-```bash
-cd env/lib/python3.7/site-packages/
-ln -s ~/opencv/build/cv2.so cv2.so
-```
-
-The last step is to put ``~/opencv/build/lib/libopencv_java430.so`` to the ``/usr/lib`` directory:
+The last step is to put ``~/opencv/build/lib/libopencv_java430.so`` into the ``/usr/lib`` directory:
 
 ```bash
 sudo cp lib/libopencv_java430.so /usr/lib
 ```
 
-For Windows and macOS OpenCV Java build, please, follow the steps described in [Installing OpenCV for Java](https://opencv-java-tutorials.readthedocs.io/en/latest/01-installing-opencv-for-java.html).
+For Windows and macOS OpenCV Java build, please, follow the steps described in [Introduction to Java Development](https://docs.opencv.org/master/d9/d52/tutorial_java_dev_intro.html) or [Installing OpenCV for Java](https://opencv-java-tutorials.readthedocs.io/en/latest/01-installing-opencv-for-java.html).
 
 
 ## Executing Model Conversion and Test Script