camera.py 文件源码

def _set_annotate_foreground(self, value):
        self._check_camera_open()
        if not isinstance(value, Color):
            raise PiCameraValueError(
                'annotate_foreground must be a Color')
        elif not self._annotate_v3:
            if value.rgb_bytes != (255, 255, 255):
                warnings.warn(
                    PiCameraFallback(
                        "Firmware does not support setting a custom foreground "
                        "annotation color; using white instead"))
            return
        mp = self._get_annotate_settings()
        mp.custom_text_color = True
        (
            mp.custom_text_Y,
            mp.custom_text_U,
            mp.custom_text_V,
            ) = value.yuv_bytes
        mmal_check(
            mmal.mmal_port_parameter_set(self._camera[0].control, mp.hdr),
            prefix="Failed to set annotation foreground")