Xuggle和Java库路径

Question

我正在用Java编写截屏应用程序。我决定使用Xuggle进行操作，并且按照xuggle Wiki上的安装说明进行操作。

我使用％XUGGLE_HOME％\ bin和％XUGGLE_HOME％\ lib设置了PATH环境。一切似乎都还可以。我将此应用程序作为RCP插件。我在“
RCP-mail”模板上进行了尝试，插件正常工作，并且视频生成正确。

但是，当我决定在“真实”应用程序上使用它时，该插件崩溃并显示一条奇怪的错误消息：

开始捕获

2011-11-10 08：08：45,438 [Thread-5]警告com.xuggle.ferry.JNILibraryLoader-
故障：库的库加载：xuggle-xuggler; 版本：3：绝对路径：C：\ Program Files（x86）\ Xuggle \ bin \
libxuggle-xuggler-3.dll; 错误：java.lang.UnsatisfiedLinkError：C：\ Program
Files（x86）\ Xuggle \ bin \ libxuggle-xuggler-3.dll：找不到依赖的库

2011-11-10 08：08：45,447 [Thread-5]警告com.xuggle.ferry.JNILibraryLoader-
错误：库的库加载：xuggle-xuggler; 版本：3：绝对路径：C：\ Program Files（x86）\ Xuggle \ bin \
libxuggle-xuggler-3.dll; 错误：java.lang.UnsatisfiedLinkError：C：\ Program
Files（x86）\ Xuggle \ bin \ libxuggle-xuggler-3.dll：找不到依赖的库

2011-11-10 08：08：45,453 [Thread-5] com.xuggle.ferry.JNILibraryLoader错误-
无法加载库：xuggle-xuggler; 版本：3;
请访问http://www.xuggle.com/xuggler/faq/以找到针对该问题的常见解决方案

但这很奇怪，因为java.library.path定义明确：

logger.info(System.getProperty("java.library.path"));

退货

Nov 10, 2011 8:08:45 AM com.gvs.tools.ui.record.video.handler.RecordHandler startRecording
INFO: C:\Program Files (x86)\Java\jre6\bin;C:\Windows\Sun\Java\bin;C:\Windows\system32;C:\Windows;C:/Program Files (x86)/Java/jre6/bin/client;C:/Program Files (x86)/Java/jre6/bin;C:/Program Files (x86)/Java/jre6/lib/i386;C:\Program Files (x86)\Xuggle\bin;C:\Program Files (x86)\Xuggle\lib;C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files (x86)\JProbe 8.3\bin;C:\Program Files\TortoiseSVN\bin;D:\Work\Paul\eclipse;;.

使该插件与该应用程序一起使用时我缺少什么？该问题是由于应用程序使用其他本机库（例如3D-dll）导致的吗？

这是用于制作截屏视频的代码：

RecordHandler.java:
    private void startRecording() {

    Logger logger = Logger.getLogger(RecordHandler.class.getName());
    logger.info(System.getProperty("java.library.path"));

    // Initialize framesQueue
    framesQueue =  new LinkedBlockingQueue<BufferedImage>();
    // Initialize the capture thread
    captureThread =  new ScreenCapturer();
    captureThread.setCaptureFramesQueue(framesQueue);

    // Initialize the recorder
    encoderThread = new FrameEncoder("test.mp4");
    encoderThread.setCapturedFramesQueue(framesQueue);

    // Start capture
    captureThread.start();
    // wait for the Queue to be feed before encoding
    try {
        Thread.sleep(1000L);
    } catch (InterruptedException e) {
    }
    encoderThread.start();
}

ScreenCapturer.java：

    @Override
public void run() {
    // Retrieve the application main window's shell
    Display.getDefault().asyncExec(new Runnable() {

        @Override
        public void run() {
            appShell = Display.getCurrent().getActiveShell();
        }
    });

    isRunning = true;
    System.out.println("Starting Capture");
    for (numberOfFramesTaken = 0; isRunning && numberOfFramesTaken <= IVideoEncoderConfiguration.MAXIMUM_NUMBER_OF_FRAMES; numberOfFramesTaken++) {
        try {
            takeScreenShot();
            Thread.sleep(IVideoEncoderConfiguration.CAPTURE_TIME_INTERVAL_MILLIS);
        } catch (InterruptedException e) {
        }
    }
    System.out.println("Capture has ended");
    System.out.println("Number of frames taken: "
            + numberOfFramesTaken);
}

/**
 * Take a screen capture and store it in the capturedFramesQueue
 */
private void takeScreenShot() {
    Display.getDefault().asyncExec(new Runnable() {
        @Override
        public void run() {
            if (appShell != null) {
                Rectangle bounds = appShell.getBounds();
                java.awt.Rectangle awtBounds =  new java.awt.Rectangle(bounds.x, bounds.y, bounds.width, bounds.height);
                final BufferedImage screenCapture =  robot.createScreenCapture(awtBounds);
                try {
                    capturedFramesQueue.put(screenCapture);
                } catch (InterruptedException e) {
                }
            }
        }
    });
}

FrameEncoder.java：

public void run() {
    isRunning = true;
    String outFile = outputdirectoryPath + outputFileName;
    // First, let's make a IMediaWriter to write the file.
    final IMediaWriter writer = ToolFactory.makeWriter(outFile);
    // Retrieve the first frame to guess video dimensions
    BufferedImage firstFrame = null;
    try {
        firstFrame = capturedFramesQueue.take();
    } catch (InterruptedException e) {
    }
    if (firstFrame == null) {
        return;
    }
    // We tell it we're going to add one video stream, with id 0,
    // at position 0, and that it will have a fixed frame rate of
    // FRAME_RATE.
    writer.addVideoStream(0, 0,
            IVideoEncoderConfiguration.FRAME_RATE,
            firstFrame.getWidth(), firstFrame.getHeight());

    long startTime = System.nanoTime();
    for (numberOfFramesRecorded = 0; isRunning
            && numberOfFramesRecorded <= IVideoEncoderConfiguration.MAXIMUM_NUMBER_OF_FRAMES; numberOfFramesRecorded++) {
        // Retrieve the captured frame
        try {
            final BufferedImage currentFrame = convertToType(capturedFramesQueue.take(), BufferedImage.TYPE_3BYTE_BGR);
            // encode the next frame
            writer.encodeVideo(0, currentFrame, System.nanoTime() - startTime,
                    TimeUnit.NANOSECONDS);
            // sleep, time depending of FRAME_RATE
            Thread.sleep(IVideoEncoderConfiguration.CAPTURE_TIME_INTERVAL_MILLIS);
        } catch (InterruptedException e) {
        }
    }
    // Get the remaining frame on the queue
    Collection<BufferedImage> frames = new LinkedList<BufferedImage>();
    capturedFramesQueue.drainTo(frames, IVideoEncoderConfiguration.MAXIMUM_NUMBER_OF_FRAMES - numberOfFramesRecorded);
    for (BufferedImage frame : frames) {
        BufferedImage currentFrame = convertToType(frame, BufferedImage.TYPE_3BYTE_BGR);
        writer.encodeVideo(0, currentFrame, System.nanoTime() - startTime,
                TimeUnit.NANOSECONDS);
    }
    // close the MediaWriter, write the trailer if needed
    writer.close();
}

Answer 1

我知道已经晚了一点，但是问题是Xuggler要求所有的DLL都位于操作系统的加载路径环境中，而不仅仅是java.library.path

这意味着与Xuggle一起安装的所有DLL（例如libavcodec.dll）都必须位于启动Java的进程的％PATH％环境变量中。