Xuggle和java库路径

Question

我正在用Java编写一个屏幕广播应用程序。我决定使用Xuggle来做这件事，然后按照xuggle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。一切看起来都还好。我把这个应用程序作为一个RCP插件。我在"RCP-mail“模板上尝试过，插件工作正常，视频生成也是正确的。

但是，当我决定在“真实”应用程序上使用它时，插件出现了一个奇怪的错误消息：

起始捕获

2011-11-10 08:08:45,438线程-5警告com.xuggle.ferry.JNILibraryLoader -失败:库加载库:Xuggle xuggler；版本: 3:绝对路径: C:\Program (X86)\Xuggle\bin\libxuggle 3.dll；错误: java.lang.UnsatisfiedLinkError: C:\Program (X86)\Xuggle\bin\libxuggle 3.Can:无法找到依赖的库

2011-11-10 08:08:45,447线程-5警告com.xuggle.ferry.JNILibraryLoader -失败:库加载库:Xuggle xuggler；版本: 3:绝对路径: C:\Program (X86)\Xuggle\bin\libxuggle 3.dll；错误: java.lang.UnsatisfiedLinkError: C:\Program (X86)\Xuggle\bin\libxuggle 3.Can:无法找到依赖的库

2011-11-10 08:08:45,453线程-5错误com.xuggle.ferry.JNILibraryLoader -无法加载库；版本: 3；访问http://www.xuggle.com/xuggler/faq/以找到解决此问题的通用解决方案。

但这很奇怪，因为java.library.path定义得很好：

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

返回

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;;.

我缺少什么来让这个应用程序的插件工作呢？此问题是由于应用程序使用其他本机库(如3D-dll )造成的吗？

下面是用来制作屏幕视频的代码：

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

我知道现在有点晚了，但问题是Xuggler要求所有的ALL都在操作系统加载路径环境中，而不仅仅是java.library.path。

这意味着所有用libavcodec.dll安装的DLL都需要在启动Java的进程的%PATH%环境变量中。

Answer 2

原因可能是依赖jars或版本冲突不可用。

在类路径中添加以下jars对我来说很好：

-5.4.jar slf4j-api-1.6.4.jar logback-核心-1.0.jar logback-经典-1.0.jar