Developer Documentation

QuickTime 4 API Documentation

Inside Macintosh: QuickTime

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Video Media Handler Functions

Video media handlers are responsible for interpreting and manipulating video data. These media handlers allow you to call them directly to work with some graphics settings. This section describes the functions supported by video media handlers.

Video media handlers maintain a graphics mode and color value that affect the display of video data. You can use the SetVideoMediaGraphicsMode and GetVideoMediaGraphicsMode functions to work with these characteristics. See Inside Macintosh: Imaging for more information about setting color values for use with the addPin , subPin , blend , and transparent drawing modes.

Sample descriptions for video media are stored in image description structures. For a complete discussion of the format and content of the image description structure, see the chapter "Image Compression Manager" in this book.

SetVideoMediaGraphicsMode

The SetVideoMediaGraphicsMode function allows you to set the graphics mode and blend color of a video media.

pascal HandlerError SetVideoMediaGraphicsMode (MediaHandler mh,
                                         long graphicsMode,
                                         const RGBColor *opColor);
mH
Contains a reference to a media handler. You obtain this reference from the GetMediaHandler function, which is described on GetMediaHandler .

graphicsMode
Specifies the graphics mode of the media handler. This is a QuickDraw transfer mode value.

opColor
Contains a pointer to the color for use in blending and transparent operations. The media handler passes this color to QuickDraw as appropriate when you draw in addPin , subPin , blend , or transparent mode.

ERROR CODES

Component Manager errors

SEE ALSO

You can retrieve the graphics mode and blend color currently in use by a video media handler by calling the GetVideoMediaGraphicsMode function, which is described in the next section.

GetVideoMediaGraphicsMode

The GetVideoMediaGraphicsMode function allows you to obtain the graphics mode and blend color values currently in use by a video media handler .

pascal HandlerError GetVideoMediaGraphicsMode (MediaHandler mh,
                                         long *graphicsMode,
                                         RGBColor *opColor);
mH
Contains a reference to a media handler. You obtain this reference from the GetMediaHandler function, which is described on GetMediaHandler .

graphicsMode
Contains a pointer to a long integer. The media handler returns the graphics mode currently in use by the media handler. This is a QuickDraw transfer mode value.

opColor
Contains a pointer to an RGB color structure. The Movie Toolbox returns the color currently in use by the media handler. This is the blend value for blends and the transparent color for transparent operations. The Movie Toolbox supplies this value to QuickDraw when you draw in addPin , subPin , blend , or transparent mode.

ERROR CODES

Component Manager errors

SEE ALSO

You can set the graphics mode and blend color of a video media handler by calling the SetVideoMediaGraphicsMode function, which is described in the previous section.

© 1999 Apple Computer, Inc.

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