Merge pull request #313 from krok32/master

sarxos · sarxos · commit 2ad6b817820e · 2015-02-17T00:18:29.000+01:00
Passing parameters to WebcamDevice instances, issue #307
diff --git a/webcam-capture/src/main/java/com/github/sarxos/webcam/Webcam.java b/webcam-capture/src/main/java/com/github/sarxos/webcam/Webcam.java
@@ -8,6 +8,7 @@
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Map;
 import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
@@ -20,6 +21,7 @@
 import org.slf4j.LoggerFactory;
 
 import com.github.sarxos.webcam.WebcamDevice.BufferAccess;
+import com.github.sarxos.webcam.WebcamDevice.Configurable;
 import com.github.sarxos.webcam.WebcamUpdater.DefaultDelayCalculator;
 import com.github.sarxos.webcam.WebcamUpdater.DelayCalculator;
 import com.github.sarxos.webcam.ds.buildin.WebcamDefaultDevice;
@@ -764,6 +766,23 @@ public void getImageBytes(ByteBuffer target) {
 		}
 	}
 
+	/**
+	 * If the underlying device implements Configurable interface, specified
+	 * parameters are passed to it. May be called before the open method or
+	 * later in dependence of the device implementation.
+	 * 
+	 * @param parameters - Map of parameters changing device defaults
+	 * @see Configurable
+	 */
+	public void setParameters(Map<String, ?> parameters) {
+		WebcamDevice device = getDevice();
+		if (device instanceof Configurable) {
+			((Configurable) device).setParameters(parameters);
+		} else {
+			LOG.debug("Webcam device {} is not configurable", device);
+		}
+	}
+	
 	/**
 	 * Is webcam ready to be read.
 	 *
diff --git a/webcam-capture/src/main/java/com/github/sarxos/webcam/WebcamDevice.java b/webcam-capture/src/main/java/com/github/sarxos/webcam/WebcamDevice.java
@@ -3,6 +3,7 @@
 import java.awt.Dimension;
 import java.awt.image.BufferedImage;
 import java.nio.ByteBuffer;
+import java.util.Map;
 
 
 /**
@@ -56,6 +57,27 @@ public static interface FPSSource {
 
 	}
 
+	/**
+	 * This interface may be implemented by devices which expect any specific
+	 * parameters.
+	 * 
+	 * @author Martin Krok (krok32) 
+	 */
+	public static interface Configurable {
+
+		/**
+		 * Sets device parameters. Each device implementation may accept its own
+		 * set of parameters. All accepted keys, value types, possible values
+		 * and defaults should be reasonably documented by the implementor. May
+		 * be called before the open method or later in dependence of the device
+		 * implementation.
+		 * 
+		 * @param parameters - Map of parameters changing device defaults
+		 * @see Webcam#setParameters(Map)
+		 */
+		void setParameters(Map<String, ?> parameters);
+	}
+	
 	/**
 	 * Get device name.
 	 * 
