Lines Matching full:control

14 control ioctls provide the information and a mechanism to create a nice
21 pre-defined control IDs have the prefix ``V4L2_CID_``, and are listed in
22 :ref:`control-id`. The ID is used when querying the attributes of a
23 control, and when getting or setting the current value.
26 assumptions about their purpose. Each control comes with a name string
36 value, step size or other menu items. A control with a certain *custom*
39 If a control is not applicable to the current configuration of the
43 Control values are stored globally, they do not change when switching
52 in order to always reflect the correct control value.
59 Control IDs
105     ``V4L2_CID_BRIGHTNESS``). This control is deprecated and should not
112     This is an action control. When set (the value is ignored), the
128     ``V4L2_CID_GAMMA``. This control is deprecated and should not be
135     Automatic gain/exposure control.
138     Gain control.
140     Primarily used to control gain on e.g. TV tuners but also on
141     webcams. Most devices control only digital gain with this control
166     Enables automatic hue control by the device. The effect of setting
167     ``V4L2_CID_HUE`` while automatic hue control is enabled is
171     This control specifies the white balance settings as a color
186     Chroma automatic gain control.
189     Adjusts the Chroma gain control (for use when chroma AGC is
244 	determined by ``V4L2_CID_COLORFX_CBCR`` control.
247         by ``V4L2_CID_COLORFX_RGB`` control.
286     This is a read-only control that can be read by the application and
292     This is a read-only control that can be read by the application and
305     control lets you select the alpha component value of all pixels.
308     the device supports alpha channel processing this control lets you
313     End of the predefined control IDs (currently
317     ID of the first custom (driver specific) control. Applications
324 control value with the :ref:`VIDIOC_G_CTRL <VIDIOC_G_CTRL>` and
362 	    printf("Control %s\\n", queryctrl.name);
387 	    printf("Control %s\\n", query_ext_ctrl.name);
415 	    printf("Control %s\\n", queryctrl.name);
434 	    printf("Control %s\\n", queryctrl.name);
454     struct v4l2_control control;
469 	memset(&control, 0, sizeof (control));
470 	control.id = V4L2_CID_BRIGHTNESS;
471 	control.value = queryctrl.default_value;
473 	if (-1 == ioctl(fd, VIDIOC_S_CTRL, &control)) {
479     memset(&control, 0, sizeof(control));
480     control.id = V4L2_CID_CONTRAST;
482     if (0 == ioctl(fd, VIDIOC_G_CTRL, &control)) {
483 	control.value += 1;
487 	if (-1 == ioctl(fd, VIDIOC_S_CTRL, &control)
498     control.id = V4L2_CID_AUDIO_MUTE;
499     control.value = 1; /* silence */
502     ioctl(fd, VIDIOC_S_CTRL, &control);
508    since the meaning of the control with that ID is driver dependent. In