Notes On Using Multiple Aja Products; Using 8-Bit Versus 10-Bit Video - AJA KONA LHI Installation And Operation Manual

Notes on using
multiple AJA
Products:

Using 8-bit Versus 10-bit Video

KONA LHi Installation & Operation Guide — Using 8-bit Versus 10-bit Video
application, that application will use the new product for its input/ output, while the first
application you launched will continue to use the other AJA product.
Example: select a KONA LHi as the targeted product in the AJA Control Panel application.
Launch your editing application (eg. Premiere Pro). The application is now using the KONA
LHi for its input/output. Go back to the AJA Control Panel application and select an Io
Express as the "targeted" product. Launch the AJA TV application. AJA TV would now use
the Io Express for its output. If you switch back to Premiere Pro, you would note that it is still
using the KONA LHi for its input/output. Note that some applications, like AJA TV, have a
provision for playing in the background, so playback on one product could even continue
when switching the targeted device for use with another application. You can even feed
the output from one AJA product to another AJA product on the same system in such
cases.
AJA TV Preferences, Continue Playback when AJA TV is in background
AJA TV optionally supports playback in the background; checkbox "Continue Playback when
AJA TV is in background.
Performance of multi-product use depends on a variety of factors: CPU usage, RAM, disk IOPS/
bandwidth for streams of video, etc. and therefore performance may vary. Also be aware that
multiple input/output streams are only supported by software that is explicitly designed for a
multi-product environment.
While both 8- and 10-bit uncompressed video are capable of providing excellent quality
broadcast video, 10-bit represents a significantly higher quality and is preferable in many
situations.
Because 10-bit video has four times the numerical precision when compared to 8-bit, it has a
signal-to-noise ratio 12 db higher than 8-bit video.
Visually, in 8-bit video compared to 10-bit video, you will notice a substantial difference. In 8-bit
video there will be "contour lines" or "striations" visible, particularly noticeable in scenes having
soft gradients like a ramp or sunset. For example, if a sky region is mostly the same color but
varies by only a few digital numbers from one side of the picture to another, you may see
contour lines where the signal passes from one digital value to the next higher value.
Since each numerical value in a 10-bit system is only one fourth as large as an 8-bit system's,
these contours become invisible and the sky varies smoothly.
10-bit video is often used when the source and output video (or "master") is also 10-bit. Even if
the input and/or output video is 8-bit, a 10-bit "project" will still maintain a higher quality when
there is a significant amount of effects rendering involved.
Industry standard professional mastering formats—Sony Digital Betacam for Standard
Definition and Panasonic D5 for High Definition—are both true 10-bit formats.
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