QGE 100 • Reference Information 5454
TIP: In addition to the improved image quality that digital sources provide, they
are also more efficient on encoding. This is because analog sources invariably
contain a certain amount of noise and this can add to the overall content of
the data stream. In addition, analog sources may produce contouring effects
during motion.
• Network Bandwidth — This is the total volume of data that can be handled by
the network at any given time. If you have a high bandwidth network and only one
QGE 100, it is unlikely that you will experience any problems. However, in extreme
circumstances, if you have a low bandwidth network, a network with heavy traffic, or
you are using several QGEs, you may nd that the available bandwidth is insufcient
to cope during peak demand. It is important to note that the network is only as good
as its weakest link. For example, if you have a 100BASE-T network with a 10BASE-T
router, the effective bandwidth could be much less than expected.
• Data Decoding – Whatever viewing platform you are using (in other words, whether
the QGE 100 running on a computer or a Quantum Elite processor) the efciency
with which the data stream is decoded largely depends on the capacity of the central
processing unit (CPU). As with the encoding process, the decoder can choose to
reduce the refresh rate.
The most likely cause of a bottleneck here is placing too much demand on the CPU,
so that it cannot decode the QGE data stream quickly enough.
• If you are using the QGE 100 Viewer, the CPU of the computer should be as fast
as possible. Also, remember that running other applications at the same time as
the Viewer creates extra demand for the CPU.
• If you are using a Quantum processor, remember that the number of sources it is
displaying plus the content of those sources impacts how much work the CPU has
to do.
• Sources that are scaled up or down (rather than being viewed at their native
resolutions) require more CPU time (see “Source scaling”).
Source scaling
For optimal viewing, it is preferable to display a source at its native resolution (that is,
unity, not scaled). This results in the viewed source being a pixel-for-pixel copy of the
original, which keeps processing to a minimum and ensures the best possible image
quality.
Scaling a source requires each pixel value to be recalculated and, consequently, places a
high demand on the CPU. This can lead to increased latency and reduced refresh rates as
described above. In addition, since each pixel is recalculated, the image may not appear as
sharp as the original. This becomes more noticeable as the image gets smaller, especially if
the image contains fine detail.
