AJA io hd, Инструкция по установке и эксплуатации

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Io HD Installation and Operation Manual — Understanding Typical Workflows
As quality and codecs improve, the lines between offline and online are blurring.
For example, with the DVCPRO HD codec introduced in FCP HD (v.4.5),
native HD editing in the codec became possible, providing very high quality
results (true HD editing) at low data rates. Compare this to 100MB/sec and
higher for uncompressed HD formats, and you can immediately see the
benefits. ProRes 422 and ProRes 422 (HQ) take this equation one step further
by providing attributes for a compressed codec that exceed DVCProHD—with
full size video (not scaled) at 10 bit quality (as opposed to 8 bit) that is visually
lossless.
Following are summaries of the most common workflows, listing data rates and
relative quality levels. Some workflows require a RAID array and some will work
using the host Apple computer's internal system drive—it's noted where this is
supported in the following discussions.
DV/DV25 (SD) Data rate: 3+ MB/second (megabyte/second) standard definition only—
supported by internal system drive
Quality: Good
DV is commonly input to an Apple computer via FireWire. Io HD can capture
directly to DV compressed media from an uncompressed SDI source. For
devices that may not have FireWire (IEEE1394 or i.Link) connections, this
allows the user to capture to this low data rate, yet good quality codec. While
DV does offer good quality, it has lower chroma resolution when compared to
DV50, JPEG, or uncompressed. The Io HD can be used to convert DV projects
to uncompressed-in real time-for monitoring and/or output even if you haven't
captured the footage using the Io HD.
DV50 (SD) Data rate: 6+ MB/second standard definition only—supported by internal
system drive
Quality: Very Good
Like DV25, Final Cut Pro also supports the Panasonic DV50 standard
definition codec. DV50 is a 4:2:2 compressed format and therefore has higher
chroma resolution when compared to DV25. Also like DV25, you can use Io
HD to convert DV50 projects to uncompressed—in real time—for monitoring
and/or output. Io HD can capture from its SDI input, directly to DV50
compression.
Uncompressed
8-bit 4:2:2 (SD) Data rate: 21 MB/sec for standard definition—external storage recommended
Quality: Excellent, broadcast quality
Capturing in uncompressed results in clearly defined video, at full raster size and
4:2:2 chroma sampling. Using uncompressed maintains high quality from
capture all the way through effects rendering. Final Cut Pro supports RT with
uncompressed media using RT Extreme. Io HD supports capture of
uncompressed standard definition video through its SDI input. Uncompressed
media can output via all of the Io HD outputs simultaneously.