OmniTek OTR 1001, Руководство пользователя

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OmniTek OTR 1001 User Guide, v3.1a S-4
Operating Modes
There are three distinct operating modes to quality analysis on the OTR – Internal/Internal;
Internal/External; and External/External. The required operating mode is set on the PQA
Toolbar. A brief introduction to the different modes and to the PQA Toolbar is given below.
Internal/Internal
In Internal/Internal mode, the two internal generators are each used to play stored images or
image sequences. Generator 1 is used to play the reference sequence, while Generator 2 is used
to play the test sequence. No external connections to the unit are necessary. The sequences are
set to play in an endless loop and are automatically synchronized.
This mode is typically used to test the quality of copies generated by other equipment.
Internal/External
Internal/External mode is used to determine the effect on picture quality of a transmission path
(typically through one or more pieces of equipment).
The chosen sequence is played in an infinite loop on Generator 1. The output from this generator
is fed both to the external hardware under test and directly into the OTR’s Analyser, while the
output from the external hardware is fed back into one of the OTR’s SDI inputs. The calculations
performed by the OTR then show the differences that have resulted from passing the signal
through the external hardware.
External/External
In this mode, two separate source signals are fed into the OTR, which looks at the difference
between the two signals. This mode may be used to determine the level of degradation suffered
at different points in a transmission chain. Another typical use for the External/External mode is
in production testing.
For these tests, the choice of which signal takes the role of the reference signal and which takes
the role of the test signal depends on which signal has suffered the greater external delay because
that signal needs to be treated as the Test signal.
Note: Generator functions are disabled in External/External mode.
PQA Toolbar
Mode Selection Compensation Measurement
Figure S-3: PQA Toolbar
This toolbar is displayed towards the bottom of the View window when the OTR is in
PQA Mode. There are three main parts to the toolbar:
1. Mode Selection – i.e. where you select Internal/Internal; Internal/External;
External/External.
2. Compensation – the various adjustments that are currently being applied: these may be
updated either manually or automatically (see ‘3’ below).
3. Measurement – the values that the OTR has determined as the appropriate adjustments,
based on the analysis being carried out by the In-Service A/V Measurement facility –
together with an
Auto button that both prompts the measurement to be made and copies
certain values to the Compensation section of the toolbar. Note: By default, the Auto
option just uses the Frames value to set the Video delay but it can also be set to transfer
gain and offset values as well by ticking the
Auto apply gain/offset compensation
option included on the Video Config page of the Config window (see Section T.2).
For further information, see Step 3 below.