User`s guide

CHAPTER
13
1
About the V4HD
OVERVIEW
The V4HD is a FireWire video interface that can
operate in two modes: as a video capture and
playback device for a Mac or as a stand-alone video
converter/distribution hub.
As a video interface, the V4HD connects directly to
a computer via a standard FireWire cable and turns
a Mac desktop or laptop computer into a powerful
HD/SD video production workstation equipped
with all the video and audio I/O needed to produce
broadcast quality HD and SD video material.
In Final Cut Pro, the V4HD supports full-raster
1920 x 1080 HD capture and playback using
Apple’s ProRes 422 codec in both standard and HQ
modes. The V4HD is the ideal all-in-one video
capture solution for any ProRes workflow.
TheV4HD also provides hardware-accelerated
capture and playback of DVCProHD, DVCPro50
and DVCPro25 video streams, plus 8- and 10-bit
uncompressed SD — all with convenient plug-
and-play FireWire connectivity and CPU-efficient
intra-frame editing.
The V4HD is ideal for a DVCProHD/P2 workflow
because you can immediately play back P2 clips
(either imported or ingested) with no transcoding
necessary. Conversely, you can connect any SD or
HD video source such as an HDV camera, legacy
video deck or DVD player and then capture it
directly as a DVCProHD clip in Final Cut. Many
cameras now feed their uncompressed SDI or
component output directly from the camera’s
optics and image sensor, before compression, for
the best-possible picture quality during capture
with the V4HD.
The V4HD provides hardware-accelerated SD-to-
HD up conversion for capturing SD sources in
ProRes or DVCProHD format. It also provides
hardware-accelerated HD-to-SD down
conversion.
When the V4HD is not connected to a computer
via FireWire, it operates as stand-alone video
converter/distribution hub, or as a stand-alone
audio mixer.
A wide range of video equipment can be connected
to the V4HD, from legacy SD camcorders and CRT
monitors to the latest HD cameras, video decks,
LCD reference monitors and plasmas — all at the
same time, with no cable swapping.
In all modes, the V4HD dynamically converts the
currently chosen input source to all outputs simul-
taneously. This allows you to connect all of your
HD and SD gear, choose any source from your
computer desktop and then monitor the source
material in multiple formats simultaneously as you
convert and capture. You can even monitor
material in both HD and SD simultaneously with
hardware-accelerated up/down conversion with
pull-down insertion or removal.
The V4HD provides advanced synchronization
and machine control features, including support
for time code, 9-pin machine control, video
reference and audio word clock. For audio
synchronization, the V4HD employs Direct Digital
Synthesis (DDS), a DSP-driven phase lock engine
that delivers fast lockup times and sub-frame
accuracy.