Add Linux support to GStreamer capture driver, refs #100

webcam-capture-drivers/webcam-capture-driver-gstreamer/README.md

@@ -2,8 +2,9 @@
 
 This is GStreamer driver for Webcam Capture project. It allows Webcam Capture to
 handle pictures from build-in or USB-connected webcams. It has been designed to 
-work with Windows **only**. To make use of it user have to 
-[download](http://code.google.com/p/ossbuild/) and install GStreamer application.
+work with Windows and Linux **only**. To make use of it user have to 
+[download](http://code.google.com/p/ossbuild/) and install GStreamer application 
+on Windows or use _apt-get_, _yum_ or other packages manager to install it on Linux.
 
 Currently supported GStreamer version is 0.10.x, so make sure you are installing
 the correct one! It is **not** compatible with GStreamer 1.0 and above!

webcam-capture-drivers/webcam-capture-driver-gstreamer/pom.xml

@@ -25,6 +25,15 @@
 			<artifactId>gstreamer-java</artifactId>
 			<version>1.5</version>
 		</dependency>
+		<!-- uncomment if you would like debug prints to be visible -->
+		<!-- 
+		<dependency>
+			<groupId>ch.qos.logback</groupId>
+			<artifactId>logback-classic</artifactId>
+			<version>1.0.9</version>
+		</dependency>
+		-->
+		<!-- end uncomment -->
 	</dependencies>
 
 	<build>

webcam-capture-drivers/webcam-capture-driver-gstreamer/src/example/java/ListSupportedResolutions.java

@@ -0,0 +1,28 @@
+import java.awt.Dimension;
+
+import com.github.sarxos.webcam.Webcam;
+import com.github.sarxos.webcam.ds.gstreamer.GStreamerDriver;
+
+
+public class ListSupportedResolutions {
+
+	// uncomment if you would like debug prints to be visible, and don't
+	// forget to add logback JAR and XML file as well
+	static {
+		// WebcamLogConfigurator.configure("src/example/resources/logback.xml");
+	}
+
+	static {
+		Webcam.setDriver(new GStreamerDriver());
+	}
+
+	public static void main(String[] args) {
+
+		for (Webcam webcam : Webcam.getWebcams()) {
+			System.out.println("webcam --- " + webcam.getName());
+			for (Dimension d : webcam.getViewSizes()) {
+				System.out.println("supported resolution: " + d.width + "x" + d.height);
+			}
+		}
+	}
+}

webcam-capture-drivers/webcam-capture-driver-gstreamer/src/main/java/com/github/sarxos/webcam/ds/gstreamer/GStreamerDevice.java

@@ -3,12 +3,14 @@
 import java.awt.Dimension;
 import java.awt.image.BufferedImage;
 import java.awt.image.DataBufferInt;
+import java.io.File;
 import java.nio.IntBuffer;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 
+import org.bridj.Platform;
 import org.gstreamer.Caps;
 import org.gstreamer.Element;
 import org.gstreamer.ElementFactory;
@@ -36,17 +38,21 @@ public class GStreamerDevice implements WebcamDevice, RGBDataSink.Listener, Webc
 	/**
 	 * Video format to capture.
 	 */
-	private static final String FORMAT = "video/x-raw-yuv";
+	private static final String FORMAT_MIME = "video/x-raw-yuv";
 
 	/**
 	 * All possible resolutions - populated while initialization phase.
 	 */
 	private Dimension[] resolutions = null;
 
 	/**
-	 * Device name, immutable.
+	 * Device name, immutable. Used only on Windows platform.
 	 */
 	private final String name;
+	/**
+	 * Device name, immutable. Used only on Linux platform.
+	 */
+	private final File vfile;
 
 	/* gstreamer stuff */
 
@@ -79,6 +85,12 @@ public class GStreamerDevice implements WebcamDevice, RGBDataSink.Listener, Webc
 	 */
 	protected GStreamerDevice(String name) {
 		this.name = name;
+		this.vfile = null;
+	}
+
+	protected GStreamerDevice(File vfile) {
+		this.name = null;
+		this.vfile = vfile;
 	}
 
 	/**
@@ -94,8 +106,13 @@ private synchronized void init() {
 
 		pipe = new Pipeline(name);
 
-		source = ElementFactory.make("dshowvideosrc", "source");
-		source.set("device-name", name);
+		if (Platform.isWindows()) {
+			source = ElementFactory.make("dshowvideosrc", "source");
+			source.set("device-name", name);
+		} else if (Platform.isLinux()) {
+			source = ElementFactory.make("v4l2src", "source");
+			source.set("device", vfile.getAbsolutePath());
+		}
 
 		sink = new RGBDataSink(name, this);
 		sink.setPassDirectBuffer(true);
@@ -104,7 +121,19 @@ private synchronized void init() {
 
 		filter = ElementFactory.make("capsfilter", "filter");
 
+		if (Platform.isLinux()) {
+			pipe.addMany(source, filter, sink);
+			Element.linkMany(source, filter, sink);
+			pipe.setState(State.READY);
+		}
+
 		resolutions = parseResolutions(source.getPads().get(0));
+
+		if (Platform.isLinux()) {
+			pipe.setState(State.NULL);
+			Element.unlinkMany(source, filter, sink);
+			pipe.removeMany(source, filter, sink);
+		}
 	}
 
 	/**
@@ -120,7 +149,7 @@ private static final Dimension[] parseResolutions(Pad pad) {
 		Caps caps = pad.getCaps();
 
 		Structure structure = null;
-		String format = null;
+		String mime = null;
 
 		int n = caps.size();
 		int i = 0;
@@ -134,12 +163,20 @@ private static final Dimension[] parseResolutions(Pad pad) {
 
 			LOG.debug("Found format structure {}", structure);
 
-			format = structure.getName();
-
-			if (format.equals(FORMAT)) {
-				w = structure.getRange("width").getMinInt();
-				h = structure.getRange("height").getMinInt();
-				dimensions.add(new Dimension(w, h));
+			mime = structure.getName();
+
+			if (mime.equals(FORMAT_MIME)) {
+				if (Platform.isWindows()) {
+					w = structure.getRange("width").getMinInt();
+					h = structure.getRange("height").getMinInt();
+					dimensions.add(new Dimension(w, h));
+				} else if (Platform.isLinux()) {
+					if ("YUY2".equals(structure.getFourccString("format"))) {
+						w = structure.getInteger("width");
+						h = structure.getInteger("height");
+						dimensions.add(new Dimension(w, h));
+					}
+				}
 			}
 
 		} while (i < n);
@@ -149,7 +186,13 @@ private static final Dimension[] parseResolutions(Pad pad) {
 
 	@Override
 	public String getName() {
-		return name;
+		if (Platform.isWindows()) {
+			return name;
+		} else if (Platform.isLinux()) {
+			return vfile.getAbsolutePath();
+		} else {
+			throw new RuntimeException("Platform not supported by GStreamer capture driver");
+		}
 	}
 
 	@Override
@@ -196,7 +239,7 @@ public void open() {
 			caps.dispose();
 		}
 
-		caps = Caps.fromString(String.format("%s,width=%d,height=%d", FORMAT, size.width, size.height));
+		caps = Caps.fromString(String.format("%s,width=%d,height=%d", FORMAT_MIME, size.width, size.height));
 
 		filter.setCaps(caps);
 

webcam-capture-drivers/webcam-capture-driver-gstreamer/src/main/java/com/github/sarxos/webcam/ds/gstreamer/GStreamerDriver.java

@@ -1,5 +1,6 @@
 package com.github.sarxos.webcam.ds.gstreamer;
 
+import java.io.File;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicBoolean;
@@ -14,6 +15,7 @@
 import com.github.sarxos.webcam.WebcamDevice;
 import com.github.sarxos.webcam.WebcamDriver;
 import com.github.sarxos.webcam.WebcamException;
+import com.github.sarxos.webcam.ds.gstreamer.impl.VideoDeviceFilenameFilter;
 import com.sun.jna.NativeLibrary;
 import com.sun.jna.Platform;
 
@@ -45,30 +47,41 @@ public GStreamerDriver() {
 
 	private static final void init() {
 
-		if (!Platform.isWindows()) {
-			throw new WebcamException(String.format("%s has been designed to work only on Windows platforms", GStreamerDriver.class.getSimpleName()));
-		}
+		// if (!Platform.isWindows()) {
+		// throw new
+		// WebcamException(String.format("%s has been designed to work only on Windows platforms",
+		// GStreamerDriver.class.getSimpleName()));
+		// }
 
 		LOG.debug("GStreamer initialization");
 
 		String gpath = null;
 
-		for (String path : System.getenv("PATH").split(";")) {
-			LOG.trace("Search %PATH% for gstreamer bin {}", path);
-			if (path.indexOf("GStreamer\\v0.10.") != -1) {
-				gpath = path;
-				break;
+		if (Platform.isWindows()) {
+			for (String path : System.getenv("PATH").split(";")) {
+				LOG.trace("Search %PATH% for gstreamer bin {}", path);
+				if (path.indexOf("GStreamer\\v0.10.") != -1) {
+					gpath = path;
+					break;
+				}
 			}
-		}
 
-		if (gpath != null) {
-			LOG.debug("Add bin directory to JNA search paths {}", gpath);
-			NativeLibrary.addSearchPath("gstreamer-0.10", gpath);
-		} else {
-			throw new WebcamException("GStreamer has not been installed or not in %PATH%");
+			if (gpath != null) {
+				LOG.debug("Add bin directory to JNA search paths {}", gpath);
+				NativeLibrary.addSearchPath("gstreamer-0.10", gpath);
+			} else {
+				throw new WebcamException("GStreamer has not been installed or not in %PATH%");
+			}
 		}
 
-		Gst.init(GStreamerDriver.class.getSimpleName(), new String[0]);
+		//@formatter:off
+		String[] args = new String[] {
+			//"--gst-plugin-path", new File(".").getAbsolutePath(),
+		};
+		//@formatter:on
+
+		Gst.init(GStreamerDriver.class.getSimpleName(), args);
+
 		Runtime.getRuntime().addShutdownHook(new GStreamerShutdownHook());
 	}
 
@@ -77,11 +90,28 @@ public List<WebcamDevice> getDevices() {
 
 		List<WebcamDevice> devices = new ArrayList<WebcamDevice>();
 
-		Element dshowsrc = ElementFactory.make("dshowvideosrc", "source");
+		String srcname = null;
+		if (Platform.isWindows()) {
+			srcname = "dshowvideosrc";
+		} else {
+			srcname = "v4l2src";
+		}
+
+		Element dshowsrc = ElementFactory.make(srcname, "source");
+
 		try {
-			PropertyProbe probe = PropertyProbe.wrap(dshowsrc);
-			for (Object name : probe.getValues("device-name")) {
-				devices.add(new GStreamerDevice(name.toString()));
+			if (Platform.isWindows()) {
+				PropertyProbe probe = PropertyProbe.wrap(dshowsrc);
+				for (Object name : probe.getValues("device-name")) {
+					devices.add(new GStreamerDevice(name.toString()));
+				}
+			} else if (Platform.isLinux()) {
+				VideoDeviceFilenameFilter vfilter = new VideoDeviceFilenameFilter();
+				for (File vfile : vfilter.getVideoFiles()) {
+					devices.add(new GStreamerDevice(vfile));
+				}
+			} else {
+				throw new RuntimeException("Platform unsupported by GStreamer capture driver");
 			}
 		} finally {
 			if (dshowsrc != null) {

webcam-capture-drivers/webcam-capture-driver-gstreamer/src/main/java/com/github/sarxos/webcam/ds/gstreamer/impl/VideoDeviceFilenameFilter.java

@@ -0,0 +1,27 @@
+package com.github.sarxos.webcam.ds.gstreamer.impl;
+
+import java.io.File;
+import java.io.FilenameFilter;
+
+
+public class VideoDeviceFilenameFilter implements FilenameFilter {
+
+	private static final File DEV = new File("/dev");
+
+	@Override
+	public boolean accept(File dir, String name) {
+		return dir.getName().equals("dev") && name.startsWith("video") && Character.isDigit(name.charAt(5));
+	}
+
+	public File[] getVideoFiles() {
+
+		String[] names = DEV.list(this);
+		File[] files = new File[names.length];
+
+		for (int i = 0; i < names.length; i++) {
+			files[i] = new File(DEV, names[i]);
+		}
+
+		return files;
+	}
+}