Data types 129 through 255 are available for device specific purposes.
Operation type (uint8)
The operation type specifies what action to perform on the specified
parameter. Currently defined values are:
0: assign value
The supplied values are assigned to the specified parameter. Each element
will be clamped according to its valid range. A void parameter may only be
'assigned' an empty list of boolean type. This operation will trigger the action
associated with that parameter. A boolean value may be assigned the value
zero for false, and any other value for true.
1: offset / toggle value
Each value specifies signed offsets of the same type to be added to the
current parameter values. The resulting parameter value will be clamped
according to their valid range. It is not valid to apply an offset to a void value.
Applying any offset other than zero to a boolean value will invert that value.
Operation types 2 through 127 are reserved.
Operation types 128 through 255 are available for device specific purposes.
Data (void)
The data field is 0 or more bytes as determined by the data type and number
of elements.
The category, parameter, data type and operation type partition a 24 bit operation space.
Group
ID
Parameter
Type
Index
Minimum
Maximum
Interpretation
Lens
0.0
Focus
fixed16
–
0
1
0.0 = near, 1.0 = far
0.1
Instantaneous autofocus
void
–
–
–
trigger
instantaneous autofocus
0.2
Aperture (f-stop)
fixed16
–
-1
16
Aperture Value (where
fnumber = sqrt(2^AV))
0.3
Aperture (normalised)
fixed16
–
0
1
0.0 = smallest, 1.0 = largest
0.4
Aperture (ordinal)
int16
–
0
n
Steps through available
aperture values from
minimum (0) to maximum (n)
0.5
Instantaneous
auto aperture
void
–
–
–
trigger instantaneous
auto aperture
0.6
Optical image stabilisation
boolean
–
–
–
true = enabled, false
= disabled
0.7
Set absolute zoom (mm)
int16
–
0
max
Move to specified focal length
in mm, from minimum (0) to
maximum (max)
0.8
Set absolute zoom
(normalised)
fixed16
–
0
1
Move to specified focal
length: 0.0 = wide, 1.0 = tele
0.9
Set continuous
zoom (speed)
fixed16
–
-1
+1.0
Start/stop zooming at
specified rate: -1.0 = zoom
wider fast, 0.0 = stop,
+1 = zoom tele fast
222
222
Developer Information
