Add get/set property methods for stream properties

Author: doblon8

src/main/java/io/github/doblon8/openpnp/capture/CaptureStream.java

@@ -101,6 +101,43 @@ public PropertyLimits getPropertyLimits(CaptureProperty property) {
         }
     }
 
+    /**
+     * Get the current value of a camera/stream property (e.g. zoom, exposure etc.).
+     *
+     * @param property the property to get the value for.
+     * @return the current value of the property.
+     * @throws CaptureException if an error occurs while getting the property value.
+     */
+    public int getPropertyValue(CaptureProperty property) {
+        try (Arena arena = Arena.ofConfined()) {
+            MemorySegment valuePointer = arena.allocate(ValueLayout.JAVA_INT);
+            int result = Cap_getProperty(context.getSegment(), id, property.value(), valuePointer);
+            CaptureResult captureResult = CaptureResult.values()[result];
+            return switch (captureResult) {
+                case OK -> valuePointer.get(ValueLayout.JAVA_INT, 0);
+                case PROPERTY_NOT_SUPPORTED -> throw new CaptureException("Property " + property + " is not supported by this stream.");
+                default -> throw new CaptureException("Error getting property value for property " + property + ": context, stream are invalid or value is null.");
+            };
+        }
+    }
+
+    /**
+     * Set the value of a camera/stream property (e.g. zoom, exposure etc.).
+     *
+     * @param property the property to set the value for.
+     * @param value    the value to set for the property.
+      * @throws CaptureException if an error occurs while setting the property value.
+     */
+    public void setProperty(CaptureProperty property, int value) {
+        int result =  Cap_setProperty(context.getSegment(), id, property.value(), value);
+        CaptureResult captureResult = CaptureResult.values()[result];
+        switch (captureResult) {
+            case OK -> {}
+            case PROPERTY_NOT_SUPPORTED -> throw new CaptureException("Property " + property + " is not supported by this stream.");
+            default -> throw new CaptureException("Error getting property limit for property " + property + ": context, stream are invalid.");
+        }
+    }
+
     /**
      * Check if a stream is open, i.e. is capturing data.
      *

src/test/java/Scratch.java

@@ -1,4 +1,5 @@
 import io.github.doblon8.openpnp.capture.CaptureException;
+import io.github.doblon8.openpnp.capture.CaptureProperty;
 import io.github.doblon8.openpnp.capture.LogLevel;
 import io.github.doblon8.openpnp.capture.OpenPnpCapture;
 
@@ -25,6 +26,12 @@ void main() {
             System.out.println("Stream is open: " + stream.isOpen());
             TimeUnit.SECONDS.sleep(1); // wait a bit to get the webcam ready
 
+            System.out.println("Zoom property limits: " + stream.getPropertyLimits(CaptureProperty.ZOOM));
+            System.out.println("Current zoom value: " + stream.getPropertyValue(CaptureProperty.ZOOM));
+            stream.setProperty(CaptureProperty.ZOOM, 200);
+            System.out.println("Zoom value after setting to 200: " + stream.getPropertyValue(CaptureProperty.ZOOM));
+
+
             var image = stream.capture();
             ImageIO.write(image, "png", new File("/tmp/image.png"));
             System.out.println("Captured image saved to /tmp/image.png");