QuickTime video output, which most often comes from QuickTime movies, can be displayed in windows that appear on a computer’s desktop. Because these windows are created and managed by the computer’s operating system, software that presents QuickTime video can use the operating system’s video display services to specify which display (when there is more than one video display) and window to use for video output.
There are, however, many video output devices that are not recognized by operating systems. To display QuickTime video on these devices, your software can use video output components. The components, which are normally developed by the manufacturers of video output devices, provide a standard interface for video output to a device.
The QTPlgVideoOutput class is the root of a class hierarchy branch of the plugin that provides you with services for managing video output components and the output of both still images and movies on an external device (i.e a video recorder or a camera).
Furthermore, if your device is firewire compliant, you will be able to perform output without any additional hardware.
→
The QTPlgVideoOutput class constructors are called when you create a new instance of the class, while the ˜QTPlgVideoOutput class destructor, is called automatically when the class is no more in use. Also, you can invoke the class destructor by setting the instance of the class to nil.
Once a new class instance is returned, it is good practice to check the class property to be sure that the new object can be used. See the validity conditions for more details.
The class provides you with the following initializer methods:
()
This is the default constructor. The new class instance will try to open a connection
to the first video output component available to the current system. If no video output component can be found, the class
instance will and you
should get rid of it; otherwise, the properties of the class will be initialized to the default settings of the video output component found
(other as QTPlgVideoOutput)
This is the copy constructor. The properties of the object to be copied will be used to initialize the new class instance
properties
(fSettings as folderitem)
The new class instance will try to open a connection
to the video output component registered into the file settings specified by the
fSettings parameter; if the connection succeeds, you can use this version of the class constructor to
initialize the properties of the class with the settings
in the file
specified by the fSettings parameter
(component as )
The new class instance will try to open a connection to the video output component specified by the component parameter;
you can obtain a list of all of the currently installed video output components by using the
method of the
module,
passing to it the appropriate
.
If the connection succeeds, the properties of the class will be initialized to the default settings of the selected video output component
this property is set to true if the class instance has obtained
to the video hardware
controlled by the selected video output component; otherwise is set to false
specifies if the selected video output component
can display video both on an external video display and in a window on a computer’s desktop
specifies if the selected video output component has some sound output component
associated with it. You can find about the available sound output components by inspecting the
class property
specifies if the selected video output component has a clock component associated with it
specifies the name of application or other software that is registered
with the QTPlgVideoOutput class instance. You can use a string long up to 255 characters; if the
length of the string exceeds this limit it will be truncated
indicates the name of the software, if any, that has obtained
to the
selected video output device
the list of
supported by the selected video output component
determines the display mode currently in use by the selected video output component. You can change the
display mode only before
to the video hardware
controlled by a video output component. You can use values ranging from 0 to
of display modes–1.
You can obtain informations about available display modes by inspecting the
returned by the
class property
the list of sound output
associated to the selected video output component, if any
use this property to find about the graphics world used by the video output component to
display images. If the class instance has not obtained
to the video hardware controlled
by the selected video output component, this property returns nil
()
use this method to obtain exclusive access to the video hardware
controlled by a video output component. When your software calls this method,
the video output component acquires exclusive access to the video hardware controlled by
the specified video output component or set the
class property to –2090 if the video hardware is currently in use. If the video hardware is available,
the video output component also enables the display mode selected using the
class property
and enables the video settings, if any, that were most recently specified by the user.
If the video output component supports a custom video configuration dialog box (check the
class property to find about it),
your software can call the
method to display it. When your software no longer needs the video output component,
release it by calling
()
use this method to release access to the video hardware controlled by a video output
component. Your software should release access to a video output component as soon as it is done using
the video hardware controlled by the component. If you close the instance of a video output component
that currently has exclusive access to video hardware, the video output component automatically calls
this function to release the hardware