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The QTPlgDisplayMode class allows you to retrieve detailed informations about a specified ’s display mode; then you can use these informations wether to present a list of display modes using a graphic user interface or to choose programmatically a determined display mode for the video output component in use.
Of display mode’s characteristics, the most important is whether the mode can display the video data. This is determined by the availability of a decompressor component that takes the video data as input and converts it to the type of data, specified by the class property, required by the video output device; you can check if a display mode provide a decompressor component by examining the value of the class property. If a video output device can directly display one of the supported QuickTime pixel formats, the necessary decompressor component is included in QuickTime. If special decompressor components are required for the video output device, such as JPEG or other decompressors that deliver data directly to the video output hardware without creating a new pixel format, the class property will report the number of these decompressors.






The QTPlgDisplayMode class constructors are called when you create a new instance of the class, while the ˜QTPlgDisplayMode 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. You will obtain valid instances of this class only from the list obtained using the property of the class.

The class provides you with the following initializer methods:
(other as QTPlgDisplayMode)
This is the copy constructor. The properties of the object to be copied will be used to initialize the new class instance properties

a string that describes the display mode. Your software can use this string when presenting a list of available display modes to the user
specifies the type of pixel that is used by the display format:
  • Values of "1", "2", "4", "8", "16", "24" and "32" specify standard MacOS RGB pixel formats with corresponding bit depths
  • Values of "33", "36" and "40" specify standard MacOS gray–scale pixel formats with depths of "1", "2", "4" and "8" bits per pixel
  • Other pixel formats are specified by four–character codes. There are currently codes for RGB pixel formats defined for Microsoft Windows and for several YUV formats
specifies the width, in pixels, of the display
specifies the height, in pixels, of the display
specifies the horizontal resolution of the display, in pixels per inch
specifies the vertical resolution of the display, in pixels per inch
specifies the refresh rate of the display in Hertz
specifies if the video output device does require any special decompressors. If a video output device cannot directly display 32–bit RGB data or data in one of the other supported QuickTime pixel formats, a special decompressor is required to convert images to data that the video output device can display