OmniTek OTR 1001, User Manual

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OmniTek OTR 1001 User Guide, v3.1 N-8
Set-Up
The set-up required is summarised in the following diagram.
OmniTek Delay
Measurement System
(OTR 1001)
RVF source
(OTM/OTR/OmniTek LAB)
Transmission Path
Figure N-8: Set-up for Lip-Sync Delay measurement
Test Sequence
Measurement of audio/video delays relies on the use of a special full-motion video test sequence,
which contains precise embedded audio tones.
OmniTek has generated a special full-motion video sequence, which is available in all supported
video formats – SD, HD and 3G. Two versions of the test sequence may be provided.
The first comprises 100 frames of video that includes an uncompressed PCM tone on channels 1
and 2 of group 1 and a Dolby-E encoded tone on channels 3 and 4 of group 1. This is provided as
sets of RVF files, one for each video standard that is supported, provided in subdirectories
named
DolbyE_ < NumActiveLines >_[ Field | Frame ] /RVF_ [ i | p ]< FieldRate > Hz within an overall
Sequences/Test Sequence E directory. (For example, the directory containing the test sequence
for PAL is provided in DolbyE_576_Field/RVF_i50Hz .)
This version of the test sequence may be used to measure any of the following:
PCM delay affecting PCM source
PCM delay affecting Dolby-E source
Dolby-E delay affecting Dolby-E source
Dolby-E delay affecting PCM source
(This last mode of operation is particularly useful where a PCM source is put through a Dolby-E
encoder as the operation of de-embedding the audio and encoding it often introduces an
unknown delay.)
The other test sequence is a PCM-only version that may be used to determine just the PCM delay
affecting a PCM source for use where the equipment used to generate the test sequence does not
support RVF files. This test sequence is provided as sets of YUV files, provided in subdirectories
with names of the form <
NumActiveLines > [ _ <AspectRatio>] _[ Field | Frame ] [ _ <Frames>] /YUV
within an overall Sequences/Test Sequence A directory.