AJA IO LA, Инструкция по установке и эксплуатации, Страница: 31 / 76

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Io LD and Io LA Installation and Operation Manual — Understanding Typical
DV (DV25) Data rate: 3.13 MB/second (megabyte/second)—supported by internal system
drive
Quality: Good
In this workflow, DV is usually input to a Power Mac running Final Cut Pro 4
through its FireWire port. DV offers good quality, but it has lower Chroma
resolution when compared to DV50, JPEG, or uncompressed. You can use Io
LD
or Io
LA
to convert DV projects to uncompressed—in real time—for monitoring
and/or output. Alternatively, you can capture uncompressed from any input,
directly to DV media.
DV50 Data rate: 6.26 MB/second—supported by internal system drive
Quality: Very Good
Like DV25, Final Cut Pro 4 also supports the Panasonic DV50 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
LD
or Io
LA
to convert DV50
projects to uncompressed—in real time—for monitoring and/or output. Io
LD
or
Io
LA
can capture uncompressed from any input, directly to DV50 media.
PhotoJPEG Data rate: approximately 2-3 MB/second—supported by internal system drive
Quality: Very Good
The Apple PhotoJPEG codec offers an excellent compressed media choice for
on-line quality at low data rates. PhotoJPEG can use the full-raster at 4:2:2
sampling. Final Cut Pro 4 allows you to adjust quality using a PhotoJPEG
control panel. Io
LD
or Io
LA
will convert PhotoJPEG projects to uncompressed—
in real time—for monitoring and/or output. Io
LD
or Io
LA
can capture
uncompressed from any input, directly to PhotoJPEG media.
Uncompressed
8-bit Data rate: 21 MB/second—requires SCSI or ATA drive array
Quality: Excellent
Uncompressed media is the Io family native storage format, offering the highest
quality available. Capturing in uncompressed results in no compression
artifacts, and video is sampled over the full raster at a 4:2:2 rate. Using
uncompressed maintains a higher quality in your project from capture all the
way through effects rendering. Final Cut Pro 4 supports RT with uncompressed
media using RT Extreme. Io products support capture of uncompressed through
any inputs, and uncompressed projects are output to all outputs simultaneously.
Uncompressed
10-bit Data rate: 28 MB/second—requires SCSI or ATA drive array
Quality: Excellent, highest quality available
Offering all the benefits noted previously for 8-bit uncompressed, 10-bit
additionally offers the very highest quality available. With 10-bit media and
Final Cut Pro’s 32 bit Floating Point YUV Codec, video quality is second to
none—at any price. For more information on this subject, please see the topic at
the end of Chapter 4:
Installation and Configuration , titled “Using 8-bit Versus
10-bit Video.”