Capability Flags

Video digitizer components report their capabilities to your application by means of capability flags. These flags are formatted as part of the digitizer information structure you obtain by calling the VDGetDigitizerInfo function, which is described on VDGetDigitizerInfo . There are two sets of flags: one set describes the input capabilities of the video digitizer component; the other describes its output capabilities.

Video digitizer components support the following input capability flags:

digiInDoesNTSC: Indicates that the video digitizer supports National Television System Committee (NTSC) format input video signals. This flag is set to 1 if the digitizer component supports NTSC video.
digiInDoesPAL: Indicates that the video digitizer component supports Phase Alternation Line (PAL) format input video signals. This flag is set to 1 if the digitizer component supports PAL video.
digiInDoesSECAM: Indicates that the video digitizer component supports Systeme Electronique Couleur avec Memoire (SECAM) format input video signals. This flag is set to 1 if the digitizer component supports SECAM video.
digiInDoesGenLock: Indicates that the video digitizer component supports genlock; that is, the digitizer can derive its timing from an external time base. This flag is set to 1 if the digitizer component supports genlock.
digiInDoesComposite: Indicates that the video digitizer component supports composite input video. This flag is set to 1 if the digitizer component supports composite input.
digitInDoesSVideo: Indicates that the video digitizer component supports s-video input video. This flag is set to 1 if the digitizer component supports s-video input.
digiInDoesComponent: Indicates that the video digitizer component supports RGB input video. This flag is set to 1 if the digitizer component supports RGB input.
digiInVTR_Broadcast: Indicates that the video digitizer component can distinguish between an input signal that emanates from a videotape player and a broadcast signal. This flag is set to 1 if the digitizer component can differentiate between the two different signal types.
digiInDoesColor: Indicates that the video digitizer component supports color input. This flag is set to 1 if the digitizer component can accept color input.
digiInDoesBW: Indicates that the video digitizer component supports grayscale input. This flag is set to 1 if the digitizer component can accept grayscale input.

Video digitizer components support the following output capability flags:

digiOutDoes1: Indicates that the video digitizer component can work with pixel maps that contain 1-bit pixels. If this flag is set to 1, then the digitizer component can write images that contain 1-bit pixels. If this flag is set to 0, then the digitizer component cannot handle such images.
digiOutDoes2: Indicates that the video digitizer component can work with pixel maps that contain 2-bit pixels. If this flag is set to 1, then the digitizer component can write images that contain 2-bit pixels. If this flag is set to 0, then the digitizer component cannot handle such images.
digiOutDoes4: Indicates that the video digitizer component can work with pixel maps that contain 4-bit pixels. If this flag is set to 1, then the digitizer component can write images that contain 4-bit pixels. If this flag is set to 0, then the digitizer component cannot handle such images.
digiOutDoes8: Indicates that the video digitizer component can work with pixel maps that contain 8-bit pixels. If this flag is set to 1, then the digitizer component can write images that contain 8-bit pixels. If this flag is set to 0, then the digitizer component cannot handle such images.
digiOutDoes16: Indicates that the video digitizer component can work with pixel maps that contain 16-bit pixels. If this flag is set to 1, then the digitizer component can write images that contain 16-bit pixels. If this flag is set to 0, then the digitizer component cannot handle such images.
digiOutDoes32: Indicates that the video digitizer component can work with pixel maps that contain 32-bit pixels. If this flag is set to 1, then the digitizer component can write images that contain 32-bit pixels. If this flag is set to 0, then the digitizer component cannot handle such images.
digiOutDoesDither: Indicates that the video digitizer component supports dithering. If this flag is set to 1, the component supports dithering of colors. If this flag is set to 0, the digitizer component does not support dithering.
digiOutDoesStretch: Indicates that the video digitizer component can stretch images to arbitrary sizes. If this flag is set to 1, the digitizer component can stretch images. If this flag is set to 0, the digitizer component does not support stretching.
digiOutDoesShrink: Indicates that the video digitizer component can shrink images to arbitrary sizes. If this flag is set to 1, the digitizer component can shrink images. If this flag is set to 0, the digitizer component does not support shrinking.
digiOutDoesMask: Indicates that the video digitizer component can handle clipping regions. If this flag is set to 1, the digitizer component can mask to an arbitrary clipping region. If this flag is set to 0, the digitizer component does not support clipping regions.
digiOutDoesDouble: Indicates that the video digitizer component supports stretching to quadruple size when displaying the output video. The parameters for the stretch operation are specified in the matrix structure for the request--the component modifies the scaling attributes of the matrix (see the chapter "Movie Toolbox" in Inside Macintosh: QuickTime for information about transformation matrices). If this flag is set to 1, the digitizer component can stretch an image to exactly four times its original size, up to the maximum size specified by the maxDestHeight and maxDestWidth fields in the digitizer information structure. If this flag is set to 0, the digitizer component does not support stretching to quadruple size.
digiOutDoesQuad: Indicates that the video digitizer component supports stretching an image to 16 times its original size when displaying the output video. The parameters for the stretch operation are specified in the matrix structure for the request--the component modifies the scaling attributes of the matrix (see the chapter "Movie Toolbox" in Inside Macintosh: QuickTime for information about transformation matrices). If this flag is set to 1, the digitizer component can stretch an image to exactly 16 times its original size, up to the maximum size specified by the maxDestHeight and maxDestWidth fields in the digitizer information structure. If this flag is set to 0, the digitizer component does not support this capability.
digiOutDoesQuarter: Indicates that the video digitizer component can shrink an image to one-quarter of its original size when displaying the output video. The parameters for the shrink operation are specified in the matrix structure for the request--the component modifies the scaling attributes of the matrix (see the chapter "Movie Toolbox" in Inside Macintosh: QuickTime for information about transformation matrices). If this flag is set to 1, the digitizer component can shrink an image to exactly one-quarter of its original size, down to the minimum size specified by the minDestHeight and minDestWidth fields in the digitizer information structure. If this flag is set to 0, the digitizer component does not support this capability.
digiOutDoesSixteenth: Indicates that the video digitizer component can shrink an image to 1/16 of its original size when displaying the output video. The parameters for the shrink operation are specified in the matrix structure for the request--the digitizer component modifies the scaling attributes of the matrix (see the chapter "Movie Toolbox" in Inside Macintosh: QuickTime for information about transformation matrices). If this flag is set to 1, the digitizer component can shrink an image to exactly 1/16 of its original size, down to the minimum size specified by the minDestHeight and minDestWidth fields in the digitizer information structure. If this flag is set to 0, the digitizer component does not support this capability.
digiOutDoesRotate: Indicates that the video digitizer component can rotate an image when displaying the output video. The parameters for the rotation are specified in the matrix structure for an operation. If this flag is set to 1, the digitizer component can rotate the image. If this flag is set to 0, the digitizer component cannot rotate the resulting image.
digiOutDoesHorizFlip: Indicates that the video digitizer component can flip an image horizontally when displaying the output video. The parameters for the horizontal flip are specified in the matrix structure for an operation. If this flag is set to 1, the digitizer component can flip the image. If this flag is set to 0, the digitizer component cannot flip the resulting image.
digiOutDoesVertFlip: Indicates that the video digitizer component can flip an image vertically when displaying the output video. The parameters for the vertical flip are specified in the matrix structure for an operation. If this flag is set to 1, the digitizer component can flip the image. If this flag is set to 0, the digitizer component cannot flip the resulting image.
digiOutDoesSkew: Indicates that the video digitizer component can skew an image when displaying the output video. Skewing an image distorts it linearly along only a single axis--for example, drawing a rectangular image into a parallelogram-shaped region. The parameters for the skew operation are specified in the matrix structure for the request. If this flag is set to 1, the digitizer component can skew an image. If this flag is set to 0, the digitizer component does not support this capability.
digiOutDoesBlend: Indicates that the video digitizer component can blend the resulting image with a matte when displaying the output video. The matte is provided by the application by defining either an alpha channel or a mask plane. If this flag is set to 1, the digitizer component can blend. If this flag is set to 0, the digitizer component does not support this capability.
digiOutDoesWarp: Indicates that the video digitizer component can warp an image when displaying the output video. Warping an image distorts it along one or more axes, perhaps nonlinearly, in effect "bending" the result region. The parameters for the warp operation are specified in the matrix structure for the request. If this flag is set to 1, the digitizer component can warp an image. If this flag is set to 0, the digitizer component does not support this capability.
digiOutDoesDMA: Indicates that the video digitizer component can write to any screen or to offscreen memory. If this flag is set to 1, the digitizer component can use DMA to write to any screen or memory location.
digiOutDoesHWPlayThru: Indicates that the video digitizer component does not need idle time in order to display its video. If this flag is set to 1, your application does not need to grant processor time to the digitizer component at normal display speeds.
digiOutDoesILUT: Indicates that the video digitizer component supports inverse lookup tables for indexed color modes. If this flag is set to 1, the digitizer component uses inverse lookup tables when appropriate.
digiOutDoesKeyColor: Indicates that the video digitizer component supports clipping by means of key colors. If this flag is set to 1, the digitizer component can clip to a region defined by a key color.
digiOutDoesAsyncGrabs: Indicates that the video digitizer component can operate asynchronously. If this flag is set to 1, your application can use the VDSetupBuffers and VDGrabOneFrameAsync functions (described on VDSetupBuffers and VDGrabOneFrameAsync , respectively).
digiOutDoesUnreadableScreenBits: Indicates that the video digitizer may place pixels on the screen that cannot be used when compressing images.
digiOutDoesCompress: Indicates that the video digitizer component supports compressed source devices. These devices provide compressed data directly, without having to use the Image Compression Manager. See "Controlling Compressed Source Devices," for more information about the functions that applications can use to work with compressed source devices.
digiOutDoesCompressOnly: Indicates that the video digitizer component only provides compressed image data; the component cannot provide displayable data. This flag only applies to digitizers that support compressed source devices.
digiOutDoesPlayThruDuringCompress: Indicates that the video digitizer component can draw images on the screen at the same time that it is delivering compressed image data. This flag only applies to digitizers that support compressed source devices.

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