def set_gain(camera, analog=1, digital=1):
MMAL_PARAMETER_ANALOG_GAIN = mmal.MMAL_PARAMETER_GROUP_CAMERA + 0x59
MMAL_PARAMETER_DIGITAL_GAIN = mmal.MMAL_PARAMETER_GROUP_CAMERA + 0x5A
ret1 = mmal.mmal_port_parameter_set_rational(camera._camera.control._port,
MMAL_PARAMETER_ANALOG_GAIN,
to_rational(analog))
ret2 = mmal.mmal_port_parameter_set_rational(camera._camera.control._port,
MMAL_PARAMETER_DIGITAL_GAIN,
to_rational(digital))
if ret1 == 4 or ret2 == 4:
raise exc.PiCameraMMALError(ret, "Are you running the latest version of the userland libraries?")
elif ret1 != 0 or ret2 != 0:
raise exc.PiCameraMMALError(ret)
def set_gain(camera, gain, value):
"""Set the analog gain of a PiCamera.
camera: the picamera.PiCamera() instance you are configuring
gain: either MMAL_PARAMETER_ANALOG_GAIN or MMAL_PARAMETER_DIGITAL_GAIN
value: a numeric value that can be converted to a rational number.
"""
if gain not in [MMAL_PARAMETER_ANALOG_GAIN, MMAL_PARAMETER_DIGITAL_GAIN]:
raise ValueError("The gain parameter was not valid")
ret = mmal.mmal_port_parameter_set_rational(camera._camera.control._port,
gain, to_rational(value))
if ret == 4:
raise exc.PiCameraMMALError(
ret,
"Are you running the latest version of the userland libraries? Gain setting was introduced in late 2017."
)
elif ret != 0:
raise exc.PiCameraMMALError(ret)
def set_gain(camera, gain, value):
"""Set the analog gain of a PiCamera.
camera: the picamera.PiCamera() instance you are configuring
gain: either MMAL_PARAMETER_ANALOG_GAIN or MMAL_PARAMETER_DIGITAL_GAIN
value: a numeric value that can be converted to a rational number.
"""
# lazy loading so node does not complain
from picamera import mmal, mmalobj, exc
from picamera.mmalobj import to_rational
# keys must match the _name attribute of the corresponding class
SENSOR_GAINS = {
"analog_gain": mmal.MMAL_PARAMETER_GROUP_CAMERA + 0x59,
"digital_gain": mmal.MMAL_PARAMETER_GROUP_CAMERA + 0x5A
}
##
logging.info(f"Setting {gain} to {value}")
if gain not in ["analog_gain", "digital_gain"]:
raise ValueError("The gain parameter was not valid")
gain_int = SENSOR_GAINS[gain]
rational_value = to_rational(value)
port = camera._camera.control._port
logging.warning(gain_int)
logging.warning(rational_value)
logging.warning(port)
ret = mmal.mmal_port_parameter_set_rational(port, gain_int, rational_value)
# PLEASE NOTE
# if queried now, it will still show the old value
time.sleep(2)
if ret == 4:
raise exc.PiCameraMMALError(
ret,
"Are you running the latest version of the userland libraries? Gain setting was introduced in late 2017."
)
elif ret != 0:
raise exc.PiCameraMMALError(ret)