Add splash image and update image paths

Rename "test_image" to "images" since they're already in the examples folder
Updated paths in imread imwrite example
Fixed cv2_hardware_init/__init__.py to use full path to new example splash image

Author: sfe-SparkFro

examples/cv2_hardware_init/__init__.py

@@ -9,9 +9,11 @@
 except:
     print("Display initialization failed, skipping...")
 
-# Optional - show a splash image on the display if one is available, or clear
-# the display of any previous content
-display.splash()
+# Optional - Show a splash screen on the display with an optional filename (if
+# not provided, it defaults to `splash.png` in the root directory of the
+# MicroPython filesystem). If the file is not present, the driver will simply
+# clear the display of any previous content
+display.splash("opencv-examples/images/splash.png")
 
 # Import the camera driver
 try:

examples/ex04_imread_imwrite.py

@@ -24,7 +24,7 @@
 # 
 # Note - only BMP and PNG formats are currently supported in MicroPython OpenCV
 print("Loading image...")
-img = cv.imread("test_images/sparkfun_logo.png")
+img = cv.imread("opencv-examples/images/splash.png")
 
 # Show the image
 # 
@@ -52,7 +52,7 @@
 # 
 # Note - only BMP and PNG formats are currently supported in MicroPython OpenCV
 print("Saving modified image...")
-success = cv.imwrite("test_images/sparkfun_logo_edges.png", edges)
+success = cv.imwrite("opencv-examples/images/splash_edges.png", edges)
 
 # Check if the image was saved successfully
 if success: