我正在从连接到pc的网络摄像头捕获视频，我正在使用以下代码进行捕获：
import java.util.*;
import javax.media.*;
import javax.media.protocol.*;
import javax.media.control.*;
import javax.media.format.*;
import java.awt.*;
/**
* This is the primary class to run. It gathers an image stream and drives the processing.
*
*/
public class jmfcam05v
{
DataSource dataSource;
PushBufferStream pbs;
Vector camImgSize = new Vector();
Vector camCapDevice = new Vector();
Vector camCapFormat = new Vector();
int camFPS;
int camImgSel;
Processor processor = null;
DataSink datasink = null;
/**
* Main method to instance and run class
*
*/
public static void main(String[] args)
{
jmfcam05v jmfcam = new jmfcam05v();
}
/**
* Constructor and processing method for image stream from a cam
*
*/
public jmfcam05v()
{
// Select webcam format
fetchDeviceFormats();
camImgSel=0; // first format, or otherwise as desired
camFPS = 20; // framerate
// Setup data source
fetchDeviceDataSource();
createPBDSource();
createProcessor(dataSource);
startCapture();
try{Thread.sleep(90000);}catch(Exception e){} // 20 seconds
stopCapture();
}
/**
* Gathers info on a camera
*
*/
boolean fetchDeviceFormats()
{
Vector deviceList = CaptureDeviceManager.getDeviceList(new VideoFormat(null));
CaptureDeviceInfo CapDevice = null;
Format CapFormat = null;
String type = "N/A";
CaptureDeviceInfo deviceInfo=null;boolean VideoFormatMatch=false;
for(int i=0;i<deviceList.size();i++)
{
// search for video device
deviceInfo = (CaptureDeviceInfo)deviceList.elementAt(i);
if(deviceInfo.getName().indexOf("vfw:")<0)continue;
Format deviceFormat[] = deviceInfo.getFormats();
for (int f=0;f<deviceFormat.length;f++)
{
if(deviceFormat[f] instanceof RGBFormat)type="RGB";
if(deviceFormat[f] instanceof YUVFormat)type="YUV";
if(deviceFormat[f] instanceof JPEGFormat)type="JPG";
Dimension size = ((VideoFormat)deviceFormat[f]).getSize();
camImgSize.addElement(type+" "+size.width+"x"+size.height);
CapDevice = deviceInfo;
camCapDevice.addElement(CapDevice);
//System.out.println("Video device = " + deviceInfo.getName());
CapFormat = (VideoFormat)deviceFormat[f];
camCapFormat.addElement(CapFormat);
//System.out.println("Video format = " + deviceFormat[f].toString());
VideoFormatMatch=true; // at least one
}
}
if(VideoFormatMatch==false)
{
if(deviceInfo!=null)System.out.println(deviceInfo);
System.out.println("Video Format not found");
return false;
}
return true;
}
/**
* Finds a camera and sets it up
*
*/
void fetchDeviceDataSource()
{
CaptureDeviceInfo CapDevice = (CaptureDeviceInfo)camCapDevice.elementAt(camImgSel);
System.out.println("Video device = " + CapDevice.getName());
Format CapFormat = (Format)camCapFormat.elementAt(camImgSel);
System.out.println("Video format = " + CapFormat.toString());
MediaLocator loc = CapDevice.getLocator();
try
{
dataSource = Manager.createDataSource(loc);
}
catch(Exception e){}
try
{
// ensures 30 fps or as otherwise preferred, subject to available cam rates but this is frequency of windows request to stream
FormatControl formCont=((CaptureDevice)dataSource).getFormatControls()[0];
VideoFormat formatVideoNew = new VideoFormat(null,null,-1,null,(float)camFPS);
formCont.setFormat(CapFormat.intersects(formatVideoNew));
}
catch(Exception e){}
}
/**
* Gets a stream from the camera (and sets debug)
*
*/
void createPBDSource()
{
try
{
pbs=((PushBufferDataSource)dataSource).getStreams()[0];
}
catch(Exception e){}
}
public void createProcessor(DataSource datasource)
{
FileTypeDescriptor ftd = new FileTypeDescriptor(FileTypeDescriptor.MSVIDEO);
Format[] formats = new Format[] {new VideoFormat(VideoFormat.INDEO50)};
ProcessorModel pm = new ProcessorModel(datasource, formats, ftd);
try
{
processor = Manager.createRealizedProcessor(pm);
}
catch(Exception me)
{
System.out.println(me);
// Make sure the capture devices are released
datasource.disconnect();
return;
}
}
private void startCapture()
{
// Get the processor's output, create a DataSink and connect the two.
DataSource outputDS = processor.getDataOutput();
try
{
MediaLocator ml = new MediaLocator("file:capture.avi");
datasink = Manager.createDataSink(outputDS, ml);
datasink.open();
datasink.start();
}catch (Exception e)
{
System.out.println(e);
}
processor.start();
System.out.println("Started saving...");
}
private void pauseCapture()
{
processor.stop();
}
private void resumeCapture()
{
processor.start();
}
private void stopCapture()
{
// Stop the capture and the file writer (DataSink)
processor.stop();
processor.close();
datasink.close();
processor = null;
System.out.println("Done saving.");
}
}
该程序在Windows XP（桌面）上运行良好，并且我尝试在Windows7（笔记本电脑）上使用它，它给了我以下错误：
run: Video Format not found
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 0 >= 0
at java.util.Vector.elementAt(Vector.java:427)
at jmfcam05v.fetchDeviceDataSource(jmfcam05v.java:112)
at jmfcam05v.<init>(jmfcam05v.java:49)
at jmfcam05v.main(jmfcam05v.java:34) Java Result: 1 BUILD SUCCESSFUL (total time: 0 seconds)
我的程序未在笔记本电脑上的内置网络摄像头中检测到，也未在检测外部网络摄像头。我正在使用jmf捕获视频，并且我的所有网络摄像头均受vfw支持。
请帮我解决这个问题。
最佳答案
您要混合32位和64位安装吗？我在Windows 7下遇到类似的问题，这是由于Windows 7，JRE和JMF之间存在64位不兼容。简而言之，JMF只有32位，如果您的JRE是64位，则无法识别设备。
遵循these instructions之后，我能够识别我的相机并避免出现“找不到视频格式”以及jmfstudio未检测到视频捕获设备的情况。
关于java - Windows7上Java编程中的问题(在Windows XP中正常工作)，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/2298101/