Albalá Ingenieros HAM3000C03, Руководство пользователя, Страница: 26 / 50

Albalá Ingenieros | Manual HAM3000C03
The audio processor performs audio channel reassignment, monaural audio
generation from a stereo pair, phase inversion and signal level modification by
applying a gain. Each of these operations can be set independently for each output
audio channel.
The system introduces a minimum delay of 0.25ms for audio channels from the PGM
IN SDI program video input and AES/EBU digital audio inputs and 0.5ms for channels
from the SDI auxiliary video input. This delay is negligible for PCM audio pairs,
however it is recommended to compensate when the audio pairs are not in PCM
format.
4.3.6. Audio processor
The HAM3000C03 can assign any of the audio channels coming from the audio buffer
to each audio output channel.
The user can select generation of a monaural channel from the original stereo pair
introduced into the input audio buffer. For example, if output video signal group 1
pair 0 channel L is assigned to the audio embedded in group 2 pair 1 channel R of the
program video signal input and indicates that in group 1 pair 0 channel L mono audio
is generated, then the following audio signal appears in that channel:
G1P0LOUT = (G2P1RPGM IN + G2P1LPGM IN)/2
The user can also select secondary signal phase inversion in monaural audio
generation. Using the example above, if the user selects phase inversion in the
monaural audio generation, the output channel will be:
G1P0LOUT = (G2P1RPGM IN - G2P1LPGM IN)/2
When monaural audio is generated, both signals of the original stereo pair have the
same delay, equal to the delay specified by user for that particular output channel.
Once output channel assignment and possible conversion to monaural audio is done
the audio processor can invert the phase of the audio channel and apply a gain to the
signal which can range b24dB and -39dB, in 0.5dB steps. The user can set
the phase inversion and gain for each output audio channel independently.
4.3.7. Audio generator
The HAM3000C03 is able to generate two audio channels that can contain Greenwich
Time Signal (pips) or a continuous pure tone, selectable by the user. Pips are produced
from the VITC information included in the program video input signal. The user can
set the frequency and amplitude of these signals.
For generation of pips the module uses DVITC data if the program video input format
is SD-SDI and ATC data when the format is HD/3G-SDI. The user can select generation
of pips every hour, every half hour or every quarter of an hour. The length and number
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