Specifications

CHAPTER 1
Introduction
Optional Features 9
The software allows the user to capture or freeze a single frame of video or record a
segment of video as a QuickTime Movie. The TV window cannot be resized while the
computer is recording a movie.
Video Input 1
The optional video input card accepts video from an external source and displays the
video in a window on the computer’s display. The features of the video input card are
■ acceptance of video input in NTSC, PAL, or SECAM format
■ connectors for stereo sound, composite video, and S-video (Y/C)
■ video display in a 320-by-240 pixel window
■ pixel expansion for 640-by-480 pixel maximum display
■ video overlay capability
■ YUV format for digital video input
■ a digital video connector (DAV) for adding a video processor on an expansion card
The video input card provides AV features similar to those of the Macintosh
Quadra 660AV, with one key improvement. Whereas the Macintosh Quadra 660AV
digitizes color video using a 16-bit RGB format, the video input card uses a digital YUV
format. Because a standard television signal has more information in its chrominance
channel than in its luminance channels, digitizing the video signal as YUV format results
in a clearer picture.
The video input card can accept video input from either an external device such as a
VCR or camcorder or from the internal TV tuner module. The external device can be
connected to the video input card either through the composite video connector or the
S-video connector.
The default window size is 320-by-240 pixels; the user can resize the window up to
640-by-480 pixels—the full screen on a 14-inch monitor. The large image uses pixel
expansion of the 320-by-240 pixel image.
Note
The video input card does not work on all video monitors. It will work
with 800-by-600 pixel monitors that have a 60 Hz refresh rate, but not
with that size monitor at a 72 Hz refresh rate. In addition, 60 Hz
monitors at 800-by-600 pixels must be set to 8 bits per pixel or less. ◆
The video input card plugs into a dedicated slot on the main logic board. The slot
connector is a 60-pin microchannel connector. The module fits only its proper slot and
only in the proper orientation so that the user can safely install the video input card.
The video input card has a separate connector called the DAV (digital audio video)
connector. The DAV connector makes the digitized video data available to optional DAV
cards which may be plugged into a PCI I /O expansion slot. Such a card can contain a
hardware video compressor or other video processor. Video data cannot be output to