User manual

Automation Protocol Audio Commands
Miranda Technologies Ltd Page 159
Audio Commands
These automation commands have been developed to support the Easysound
audio model. This enables users to control audio with greater flexibility than
with earlier systems (as described on page 75). Care should be taken to
ensure that the two control methods are not used together.
All commands which address this system are preceded by a lower case ‘j’.
Further parameters will allow the user to control:
• Audio inputs
• Audio outputs
• Voice-overs
• Transitions
• Audio preview
A full set of enquiry commands are also included to enable feedback of the
audio parameters.
At various places in the Easysound audio model commands, gain values in
decibels (dB) are sent to and from the Imagestore. These are represented as a
number from 0 to 255, sent as 2 hex digits.
A floating point dB value is converted to an integer in the following way:
int dBval(float dB) // dB is in range –99.5 to 28
{
int val = (dB * 2) + 199;
if (val < 0)
{
val = 0;
}
else if (val > 255)
{
val = 255;
}
// printf("val of dB %f is: %d", dB, val);
return val;
}