au.edu.jcu.v4l4j

Class DeviceInfo

java.lang.Object

au.edu.jcu.v4l4j.DeviceInfo

public class DeviceInfo
extends Object

Objects of this class encapsulate the following information about a video device:

• its device file,
• the name of the video device,
• a list of InputInfo objects providing information about each video input,
• a list of ImageFormats, capture resolutions (ResolutionInfo) and frame intervals supported by the video device.

To retrieve information about a video device, call VideoDevice.getDeviceInfo() on its VideoDevice object, and retrieve parameters of interest. Example:
VideoDevice vd = new VideoDevice("/dev/video0");
DeviceInfo d = vd.getDeviceInfo();
System.out.println("name: "+d.getName());
System.out.println("Device file: "+d.getDeviceFile());
System.out.println("Supported formats:");
for(ImageFormat f : d.getFormatList().getNativeFormats())
System.out.println("\t"+f.toNiceString());
System.out.println("\tFormats that can be RGB24-converted: " +(vd.supportRGBConversion()?"":"None"));
if(vd.supportRGBConversion())
for(ImageFormat f: d.getFormatList().getRGBEncodableFormats())
System.out.println("\t\t"+f.toNiceString());
System.out.println("Inputs:");
for(InputInfo i: d.getInputs()){
System.out.println("\tName: "+i.getName());
System.out.println("\tType: "+i.getType()+"("+ (i.getType() == V4L4JConstants.CAMERA ? "Camera" : "Tuner")+")");
System.out.println("\tIndex: "+i.getIndex());
System.out.println("\tSupported standards:");
for(Integer s: i.getSupportedStandards()){
System.out.print("\t\t"+s);
if(s==V4L4JConstants.PAL)
System.out.println("(PAL)");
else if(s==V4L4JConstants.NTSC)
System.out.println("(NTSC)");
else if(s==V4L4JConstants.SECAM)
System.out.println("(SECAM)");
else
}
if(i.getType() == V4L4JConstants.TUNER) {
TunerInfo t = i.getTuner();
System.out.println("\tTuner");
System.out.println("\t\tname: "+t.getName());
System.out.println("\t\tIndex: "+t.getIndex());
System.out.println("\t\tRange high: "+ t.getRangeHigh());
System.out.println("\t\tRange low: "+ t.getRangeLow());
System.out.println("\t\tUnit: "+ t.getUnit()+"("+(t.getUnit() == TunerInfo.MHZ ? "MHz" : "kHz")+")");
System.out.println("\t\tType: "+ t.getType()+"("+(t.getType() == TunerInfo.RADIO ? "Radio" : "TV")+")");
}
}
vd.release();

DeviceInfo objects can not be used anymore once the matching VideoDevice object has been released. Calling any methods will then throw a StateException.

Author:

gilles

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj)
String	getDeviceFile() This method returns the device file associated with the video device.
ImageFormatList	getFormatList() This method returns an ImageFormatList object containing the various image formats, capture resolutions and frame intervals the video device supports.
List<InputInfo>	getInputs() This method returns a list of InputInfo objects which provide information about each video input supported by the video device.
String	getName() This method returns the name of the video device.
int	hashCode()
FrameInterval	listIntervals(ImageFormat imf, int width, int height) This method returns a FrameInterval object containing information about the supported frame intervals for capture at the given resolution and image format.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Method Detail

getName

public String getName()

This method returns the name of the video device.

Returns:

the name of the video device.

Throws:

StateException - if the associated VideoDevice has been released

getDeviceFile

public String getDeviceFile()

This method returns the device file associated with the video device.

Returns:

the device file

Throws:

StateException - if the associated VideoDevice has been released

getInputs

public List<InputInfo> getInputs()

This method returns a list of InputInfo objects which provide information about each video input supported by the video device.

Returns:

a list of InputInfo objects

Throws:

StateException - if the associated VideoDevice has been released

See Also:

InputInfo

getFormatList

public ImageFormatList getFormatList()

This method returns an ImageFormatList object containing the various image formats, capture resolutions and frame intervals the video device supports.

Returns:

anImageFormatList object

Throws:

StateException - if the associated VideoDevice has been released

See Also:

ImageFormatList

listIntervals

public FrameInterval listIntervals(ImageFormat imf,
                                   int width,
                                   int height)

This method returns a FrameInterval object containing information about the supported frame intervals for capture at the given resolution and image format. Note that the returned FrameInterval object could have its type set to FrameInterval.Type.UNSUPPORTED if the driver does not support frame interval enumeration OR if the device is currently being used by another application and frame intervals cannot be enumerated at this time.
Frame interval information can also be obtained through ResolutionInfo objects, attached to each ImageFormat. See getFormatList().

Parameters:

imf - the capture image format for which the frame intervals should be enumerated

width - the capture width for which the frame intervals should be enumerated

height - the capture height for which the frame intervals should be enumerated

Returns:

a FrameInterval object containing information about the supported frame intervals

Throws:

StateException - if the associated VideoDevice has been released

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object