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TOMOYO Linux Cross Reference
Linux/Documentation/userspace-api/media/v4l/ext-ctrls-camera.rst

Version: ~ [ linux-6.12-rc7 ] ~ [ linux-6.11.7 ] ~ [ linux-6.10.14 ] ~ [ linux-6.9.12 ] ~ [ linux-6.8.12 ] ~ [ linux-6.7.12 ] ~ [ linux-6.6.60 ] ~ [ linux-6.5.13 ] ~ [ linux-6.4.16 ] ~ [ linux-6.3.13 ] ~ [ linux-6.2.16 ] ~ [ linux-6.1.116 ] ~ [ linux-6.0.19 ] ~ [ linux-5.19.17 ] ~ [ linux-5.18.19 ] ~ [ linux-5.17.15 ] ~ [ linux-5.16.20 ] ~ [ linux-5.15.171 ] ~ [ linux-5.14.21 ] ~ [ linux-5.13.19 ] ~ [ linux-5.12.19 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.229 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.285 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.323 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.336 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.337 ] ~ [ linux-4.4.302 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.12 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

Diff markup

Differences between /Documentation/userspace-api/media/v4l/ext-ctrls-camera.rst (Architecture m68k) and /Documentation/userspace-api/media/v4l/ext-ctrls-camera.rst (Architecture ppc)


  1 .. SPDX-License-Identifier: GFDL-1.1-no-invari      1 .. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
  2                                                     2 
  3 .. _camera-controls:                                3 .. _camera-controls:
  4                                                     4 
  5 ************************                            5 ************************
  6 Camera Control Reference                            6 Camera Control Reference
  7 ************************                            7 ************************
  8                                                     8 
  9 The Camera class includes controls for mechani      9 The Camera class includes controls for mechanical (or equivalent
 10 digital) features of a device such as controll     10 digital) features of a device such as controllable lenses or sensors.
 11                                                    11 
 12                                                    12 
 13 .. _camera-control-id:                             13 .. _camera-control-id:
 14                                                    14 
 15 Camera Control IDs                                 15 Camera Control IDs
 16 ==================                                 16 ==================
 17                                                    17 
 18 ``V4L2_CID_CAMERA_CLASS (class)``                  18 ``V4L2_CID_CAMERA_CLASS (class)``
 19     The Camera class descriptor. Calling           19     The Camera class descriptor. Calling
 20     :ref:`VIDIOC_QUERYCTRL` for this control w     20     :ref:`VIDIOC_QUERYCTRL` for this control will
 21     return a description of this control class     21     return a description of this control class.
 22                                                    22 
 23 .. _v4l2-exposure-auto-type:                       23 .. _v4l2-exposure-auto-type:
 24                                                    24 
 25 ``V4L2_CID_EXPOSURE_AUTO``                         25 ``V4L2_CID_EXPOSURE_AUTO``
 26     (enum)                                         26     (enum)
 27                                                    27 
 28 enum v4l2_exposure_auto_type -                     28 enum v4l2_exposure_auto_type -
 29     Enables automatic adjustments of the expos     29     Enables automatic adjustments of the exposure time and/or iris
 30     aperture. The effect of manual changes of      30     aperture. The effect of manual changes of the exposure time or iris
 31     aperture while these features are enabled      31     aperture while these features are enabled is undefined, drivers
 32     should ignore such requests. Possible valu     32     should ignore such requests. Possible values are:
 33                                                    33 
 34                                                    34 
 35 .. tabularcolumns:: |p{7.1cm}|p{10.4cm}|           35 .. tabularcolumns:: |p{7.1cm}|p{10.4cm}|
 36                                                    36 
 37 .. flat-table::                                    37 .. flat-table::
 38     :header-rows:  0                               38     :header-rows:  0
 39     :stub-columns: 0                               39     :stub-columns: 0
 40                                                    40 
 41     * - ``V4L2_EXPOSURE_AUTO``                     41     * - ``V4L2_EXPOSURE_AUTO``
 42       - Automatic exposure time, automatic iri     42       - Automatic exposure time, automatic iris aperture.
 43     * - ``V4L2_EXPOSURE_MANUAL``                   43     * - ``V4L2_EXPOSURE_MANUAL``
 44       - Manual exposure time, manual iris.         44       - Manual exposure time, manual iris.
 45     * - ``V4L2_EXPOSURE_SHUTTER_PRIORITY``         45     * - ``V4L2_EXPOSURE_SHUTTER_PRIORITY``
 46       - Manual exposure time, auto iris.           46       - Manual exposure time, auto iris.
 47     * - ``V4L2_EXPOSURE_APERTURE_PRIORITY``        47     * - ``V4L2_EXPOSURE_APERTURE_PRIORITY``
 48       - Auto exposure time, manual iris.           48       - Auto exposure time, manual iris.
 49                                                    49 
 50                                                    50 
 51                                                    51 
 52 ``V4L2_CID_EXPOSURE_ABSOLUTE (integer)``           52 ``V4L2_CID_EXPOSURE_ABSOLUTE (integer)``
 53     Determines the exposure time of the camera     53     Determines the exposure time of the camera sensor. The exposure time
 54     is limited by the frame interval. Drivers      54     is limited by the frame interval. Drivers should interpret the
 55     values as 100 µs units, where the value 1     55     values as 100 µs units, where the value 1 stands for 1/10000th of a
 56     second, 10000 for 1 second and 100000 for      56     second, 10000 for 1 second and 100000 for 10 seconds.
 57                                                    57 
 58 ``V4L2_CID_EXPOSURE_AUTO_PRIORITY (boolean)``      58 ``V4L2_CID_EXPOSURE_AUTO_PRIORITY (boolean)``
 59     When ``V4L2_CID_EXPOSURE_AUTO`` is set to      59     When ``V4L2_CID_EXPOSURE_AUTO`` is set to ``AUTO`` or
 60     ``APERTURE_PRIORITY``, this control determ     60     ``APERTURE_PRIORITY``, this control determines if the device may
 61     dynamically vary the frame rate. By defaul     61     dynamically vary the frame rate. By default this feature is disabled
 62     (0) and the frame rate must remain constan     62     (0) and the frame rate must remain constant.
 63                                                    63 
 64 ``V4L2_CID_AUTO_EXPOSURE_BIAS (integer menu)``     64 ``V4L2_CID_AUTO_EXPOSURE_BIAS (integer menu)``
 65     Determines the automatic exposure compensa     65     Determines the automatic exposure compensation, it is effective only
 66     when ``V4L2_CID_EXPOSURE_AUTO`` control is     66     when ``V4L2_CID_EXPOSURE_AUTO`` control is set to ``AUTO``,
 67     ``SHUTTER_PRIORITY`` or ``APERTURE_PRIORIT     67     ``SHUTTER_PRIORITY`` or ``APERTURE_PRIORITY``. It is expressed in
 68     terms of EV, drivers should interpret the      68     terms of EV, drivers should interpret the values as 0.001 EV units,
 69     where the value 1000 stands for +1 EV.         69     where the value 1000 stands for +1 EV.
 70                                                    70 
 71     Increasing the exposure compensation value     71     Increasing the exposure compensation value is equivalent to
 72     decreasing the exposure value (EV) and wil     72     decreasing the exposure value (EV) and will increase the amount of
 73     light at the image sensor. The camera perf     73     light at the image sensor. The camera performs the exposure
 74     compensation by adjusting absolute exposur     74     compensation by adjusting absolute exposure time and/or aperture.
 75                                                    75 
 76 .. _v4l2-exposure-metering:                        76 .. _v4l2-exposure-metering:
 77                                                    77 
 78 ``V4L2_CID_EXPOSURE_METERING``                     78 ``V4L2_CID_EXPOSURE_METERING``
 79     (enum)                                         79     (enum)
 80                                                    80 
 81 enum v4l2_exposure_metering -                      81 enum v4l2_exposure_metering -
 82     Determines how the camera measures the amo     82     Determines how the camera measures the amount of light available for
 83     the frame exposure. Possible values are:       83     the frame exposure. Possible values are:
 84                                                    84 
 85 .. tabularcolumns:: |p{8.7cm}|p{8.7cm}|            85 .. tabularcolumns:: |p{8.7cm}|p{8.7cm}|
 86                                                    86 
 87 .. flat-table::                                    87 .. flat-table::
 88     :header-rows:  0                               88     :header-rows:  0
 89     :stub-columns: 0                               89     :stub-columns: 0
 90                                                    90 
 91     * - ``V4L2_EXPOSURE_METERING_AVERAGE``         91     * - ``V4L2_EXPOSURE_METERING_AVERAGE``
 92       - Use the light information coming from      92       - Use the light information coming from the entire frame and average
 93         giving no weighting to any particular      93         giving no weighting to any particular portion of the metered area.
 94     * - ``V4L2_EXPOSURE_METERING_CENTER_WEIGHT     94     * - ``V4L2_EXPOSURE_METERING_CENTER_WEIGHTED``
 95       - Average the light information coming f     95       - Average the light information coming from the entire frame giving
 96         priority to the center of the metered      96         priority to the center of the metered area.
 97     * - ``V4L2_EXPOSURE_METERING_SPOT``            97     * - ``V4L2_EXPOSURE_METERING_SPOT``
 98       - Measure only very small area at the ce     98       - Measure only very small area at the center of the frame.
 99     * - ``V4L2_EXPOSURE_METERING_MATRIX``          99     * - ``V4L2_EXPOSURE_METERING_MATRIX``
100       - A multi-zone metering. The light inten    100       - A multi-zone metering. The light intensity is measured in several
101         points of the frame and the results ar    101         points of the frame and the results are combined. The algorithm of
102         the zones selection and their signific    102         the zones selection and their significance in calculating the
103         final value is device dependent.          103         final value is device dependent.
104                                                   104 
105                                                   105 
106                                                   106 
107 ``V4L2_CID_PAN_RELATIVE (integer)``               107 ``V4L2_CID_PAN_RELATIVE (integer)``
108     This control turns the camera horizontally    108     This control turns the camera horizontally by the specified amount.
109     The unit is undefined. A positive value mo    109     The unit is undefined. A positive value moves the camera to the
110     right (clockwise when viewed from above),     110     right (clockwise when viewed from above), a negative value to the
111     left. A value of zero does not cause motio    111     left. A value of zero does not cause motion. This is a write-only
112     control.                                      112     control.
113                                                   113 
114 ``V4L2_CID_TILT_RELATIVE (integer)``              114 ``V4L2_CID_TILT_RELATIVE (integer)``
115     This control turns the camera vertically b    115     This control turns the camera vertically by the specified amount.
116     The unit is undefined. A positive value mo    116     The unit is undefined. A positive value moves the camera up, a
117     negative value down. A value of zero does     117     negative value down. A value of zero does not cause motion. This is
118     a write-only control.                         118     a write-only control.
119                                                   119 
120 ``V4L2_CID_PAN_RESET (button)``                   120 ``V4L2_CID_PAN_RESET (button)``
121     When this control is set, the camera moves    121     When this control is set, the camera moves horizontally to the
122     default position.                             122     default position.
123                                                   123 
124 ``V4L2_CID_TILT_RESET (button)``                  124 ``V4L2_CID_TILT_RESET (button)``
125     When this control is set, the camera moves    125     When this control is set, the camera moves vertically to the default
126     position.                                     126     position.
127                                                   127 
128 ``V4L2_CID_PAN_ABSOLUTE (integer)``               128 ``V4L2_CID_PAN_ABSOLUTE (integer)``
129     This control turns the camera horizontally    129     This control turns the camera horizontally to the specified
130     position. Positive values move the camera     130     position. Positive values move the camera to the right (clockwise
131     when viewed from above), negative values t    131     when viewed from above), negative values to the left. Drivers should
132     interpret the values as arc seconds, with     132     interpret the values as arc seconds, with valid values between -180
133     * 3600 and +180 * 3600 inclusive.             133     * 3600 and +180 * 3600 inclusive.
134                                                   134 
135 ``V4L2_CID_TILT_ABSOLUTE (integer)``              135 ``V4L2_CID_TILT_ABSOLUTE (integer)``
136     This control turns the camera vertically t    136     This control turns the camera vertically to the specified position.
137     Positive values move the camera up, negati    137     Positive values move the camera up, negative values down. Drivers
138     should interpret the values as arc seconds    138     should interpret the values as arc seconds, with valid values
139     between -180 * 3600 and +180 * 3600 inclus    139     between -180 * 3600 and +180 * 3600 inclusive.
140                                                   140 
141 ``V4L2_CID_FOCUS_ABSOLUTE (integer)``             141 ``V4L2_CID_FOCUS_ABSOLUTE (integer)``
142     This control sets the focal point of the c    142     This control sets the focal point of the camera to the specified
143     position. The unit is undefined. Positive     143     position. The unit is undefined. Positive values set the focus
144     closer to the camera, negative values towa    144     closer to the camera, negative values towards infinity.
145                                                   145 
146 ``V4L2_CID_FOCUS_RELATIVE (integer)``             146 ``V4L2_CID_FOCUS_RELATIVE (integer)``
147     This control moves the focal point of the     147     This control moves the focal point of the camera by the specified
148     amount. The unit is undefined. Positive va    148     amount. The unit is undefined. Positive values move the focus closer
149     to the camera, negative values towards inf    149     to the camera, negative values towards infinity. This is a
150     write-only control.                           150     write-only control.
151                                                   151 
152 ``V4L2_CID_FOCUS_AUTO (boolean)``                 152 ``V4L2_CID_FOCUS_AUTO (boolean)``
153     Enables continuous automatic focus adjustm    153     Enables continuous automatic focus adjustments. The effect of manual
154     focus adjustments while this feature is en    154     focus adjustments while this feature is enabled is undefined,
155     drivers should ignore such requests.          155     drivers should ignore such requests.
156                                                   156 
157 ``V4L2_CID_AUTO_FOCUS_START (button)``            157 ``V4L2_CID_AUTO_FOCUS_START (button)``
158     Starts single auto focus process. The effe    158     Starts single auto focus process. The effect of setting this control
159     when ``V4L2_CID_FOCUS_AUTO`` is set to ``T    159     when ``V4L2_CID_FOCUS_AUTO`` is set to ``TRUE`` (1) is undefined,
160     drivers should ignore such requests.          160     drivers should ignore such requests.
161                                                   161 
162 ``V4L2_CID_AUTO_FOCUS_STOP (button)``             162 ``V4L2_CID_AUTO_FOCUS_STOP (button)``
163     Aborts automatic focusing started with ``V    163     Aborts automatic focusing started with ``V4L2_CID_AUTO_FOCUS_START``
164     control. It is effective only when the con    164     control. It is effective only when the continuous autofocus is
165     disabled, that is when ``V4L2_CID_FOCUS_AU    165     disabled, that is when ``V4L2_CID_FOCUS_AUTO`` control is set to
166     ``FALSE`` (0).                                166     ``FALSE`` (0).
167                                                   167 
168 .. _v4l2-auto-focus-status:                       168 .. _v4l2-auto-focus-status:
169                                                   169 
170 ``V4L2_CID_AUTO_FOCUS_STATUS (bitmask)``          170 ``V4L2_CID_AUTO_FOCUS_STATUS (bitmask)``
171     The automatic focus status. This is a read    171     The automatic focus status. This is a read-only control.
172                                                   172 
173     Setting ``V4L2_LOCK_FOCUS`` lock bit of th    173     Setting ``V4L2_LOCK_FOCUS`` lock bit of the ``V4L2_CID_3A_LOCK``
174     control may stop updates of the ``V4L2_CID    174     control may stop updates of the ``V4L2_CID_AUTO_FOCUS_STATUS``
175     control value.                                175     control value.
176                                                   176 
177 .. tabularcolumns:: |p{6.8cm}|p{10.7cm}|          177 .. tabularcolumns:: |p{6.8cm}|p{10.7cm}|
178                                                   178 
179 .. flat-table::                                   179 .. flat-table::
180     :header-rows:  0                              180     :header-rows:  0
181     :stub-columns: 0                              181     :stub-columns: 0
182                                                   182 
183     * - ``V4L2_AUTO_FOCUS_STATUS_IDLE``           183     * - ``V4L2_AUTO_FOCUS_STATUS_IDLE``
184       - Automatic focus is not active.            184       - Automatic focus is not active.
185     * - ``V4L2_AUTO_FOCUS_STATUS_BUSY``           185     * - ``V4L2_AUTO_FOCUS_STATUS_BUSY``
186       - Automatic focusing is in progress.        186       - Automatic focusing is in progress.
187     * - ``V4L2_AUTO_FOCUS_STATUS_REACHED``        187     * - ``V4L2_AUTO_FOCUS_STATUS_REACHED``
188       - Focus has been reached.                   188       - Focus has been reached.
189     * - ``V4L2_AUTO_FOCUS_STATUS_FAILED``         189     * - ``V4L2_AUTO_FOCUS_STATUS_FAILED``
190       - Automatic focus has failed, the driver    190       - Automatic focus has failed, the driver will not transition from
191         this state until another action is per    191         this state until another action is performed by an application.
192                                                   192 
193                                                   193 
194                                                   194 
195 .. _v4l2-auto-focus-range:                        195 .. _v4l2-auto-focus-range:
196                                                   196 
197 ``V4L2_CID_AUTO_FOCUS_RANGE``                     197 ``V4L2_CID_AUTO_FOCUS_RANGE``
198     (enum)                                        198     (enum)
199                                                   199 
200 enum v4l2_auto_focus_range -                      200 enum v4l2_auto_focus_range -
201     Determines auto focus distance range for w    201     Determines auto focus distance range for which lens may be adjusted.
202                                                   202 
203 .. tabularcolumns:: |p{6.9cm}|p{10.6cm}|          203 .. tabularcolumns:: |p{6.9cm}|p{10.6cm}|
204                                                   204 
205 .. flat-table::                                   205 .. flat-table::
206     :header-rows:  0                              206     :header-rows:  0
207     :stub-columns: 0                              207     :stub-columns: 0
208                                                   208 
209     * - ``V4L2_AUTO_FOCUS_RANGE_AUTO``            209     * - ``V4L2_AUTO_FOCUS_RANGE_AUTO``
210       - The camera automatically selects the f    210       - The camera automatically selects the focus range.
211     * - ``V4L2_AUTO_FOCUS_RANGE_NORMAL``          211     * - ``V4L2_AUTO_FOCUS_RANGE_NORMAL``
212       - Normal distance range, limited for bes    212       - Normal distance range, limited for best automatic focus
213         performance.                              213         performance.
214     * - ``V4L2_AUTO_FOCUS_RANGE_MACRO``           214     * - ``V4L2_AUTO_FOCUS_RANGE_MACRO``
215       - Macro (close-up) auto focus. The camer    215       - Macro (close-up) auto focus. The camera will use its minimum
216         possible distance for auto focus.         216         possible distance for auto focus.
217     * - ``V4L2_AUTO_FOCUS_RANGE_INFINITY``        217     * - ``V4L2_AUTO_FOCUS_RANGE_INFINITY``
218       - The lens is set to focus on an object     218       - The lens is set to focus on an object at infinite distance.
219                                                   219 
220                                                   220 
221                                                   221 
222 ``V4L2_CID_ZOOM_ABSOLUTE (integer)``              222 ``V4L2_CID_ZOOM_ABSOLUTE (integer)``
223     Specify the objective lens focal length as    223     Specify the objective lens focal length as an absolute value. The
224     zoom unit is driver-specific and its value    224     zoom unit is driver-specific and its value should be a positive
225     integer.                                      225     integer.
226                                                   226 
227 ``V4L2_CID_ZOOM_RELATIVE (integer)``              227 ``V4L2_CID_ZOOM_RELATIVE (integer)``
228     Specify the objective lens focal length re    228     Specify the objective lens focal length relatively to the current
229     value. Positive values move the zoom lens     229     value. Positive values move the zoom lens group towards the
230     telephoto direction, negative values towar    230     telephoto direction, negative values towards the wide-angle
231     direction. The zoom unit is driver-specifi    231     direction. The zoom unit is driver-specific. This is a write-only
232     control.                                      232     control.
233                                                   233 
234 ``V4L2_CID_ZOOM_CONTINUOUS (integer)``            234 ``V4L2_CID_ZOOM_CONTINUOUS (integer)``
235     Move the objective lens group at the speci    235     Move the objective lens group at the specified speed until it
236     reaches physical device limits or until an    236     reaches physical device limits or until an explicit request to stop
237     the movement. A positive value moves the z    237     the movement. A positive value moves the zoom lens group towards the
238     telephoto direction. A value of zero stops    238     telephoto direction. A value of zero stops the zoom lens group
239     movement. A negative value moves the zoom     239     movement. A negative value moves the zoom lens group towards the
240     wide-angle direction. The zoom speed unit     240     wide-angle direction. The zoom speed unit is driver-specific.
241                                                   241 
242 ``V4L2_CID_IRIS_ABSOLUTE (integer)``              242 ``V4L2_CID_IRIS_ABSOLUTE (integer)``
243     This control sets the camera's aperture to    243     This control sets the camera's aperture to the specified value. The
244     unit is undefined. Larger values open the     244     unit is undefined. Larger values open the iris wider, smaller values
245     close it.                                     245     close it.
246                                                   246 
247 ``V4L2_CID_IRIS_RELATIVE (integer)``              247 ``V4L2_CID_IRIS_RELATIVE (integer)``
248     This control modifies the camera's apertur    248     This control modifies the camera's aperture by the specified amount.
249     The unit is undefined. Positive values ope    249     The unit is undefined. Positive values open the iris one step
250     further, negative values close it one step    250     further, negative values close it one step further. This is a
251     write-only control.                           251     write-only control.
252                                                   252 
253 ``V4L2_CID_PRIVACY (boolean)``                    253 ``V4L2_CID_PRIVACY (boolean)``
254     Prevent video from being acquired by the c    254     Prevent video from being acquired by the camera. When this control
255     is set to ``TRUE`` (1), no image can be ca    255     is set to ``TRUE`` (1), no image can be captured by the camera.
256     Common means to enforce privacy are mechan    256     Common means to enforce privacy are mechanical obturation of the
257     sensor and firmware image processing, but     257     sensor and firmware image processing, but the device is not
258     restricted to these methods. Devices that     258     restricted to these methods. Devices that implement the privacy
259     control must support read access and may s    259     control must support read access and may support write access.
260                                                   260 
261 ``V4L2_CID_BAND_STOP_FILTER (integer)``           261 ``V4L2_CID_BAND_STOP_FILTER (integer)``
262     Switch the band-stop filter of a camera se    262     Switch the band-stop filter of a camera sensor on or off, or specify
263     its strength. Such band-stop filters can b    263     its strength. Such band-stop filters can be used, for example, to
264     filter out the fluorescent light component    264     filter out the fluorescent light component.
265                                                   265 
266 .. _v4l2-auto-n-preset-white-balance:             266 .. _v4l2-auto-n-preset-white-balance:
267                                                   267 
268 ``V4L2_CID_AUTO_N_PRESET_WHITE_BALANCE``          268 ``V4L2_CID_AUTO_N_PRESET_WHITE_BALANCE``
269     (enum)                                        269     (enum)
270                                                   270 
271 enum v4l2_auto_n_preset_white_balance -           271 enum v4l2_auto_n_preset_white_balance -
272     Sets white balance to automatic, manual or    272     Sets white balance to automatic, manual or a preset. The presets
273     determine color temperature of the light a    273     determine color temperature of the light as a hint to the camera for
274     white balance adjustments resulting in mos    274     white balance adjustments resulting in most accurate color
275     representation. The following white balanc    275     representation. The following white balance presets are listed in
276     order of increasing color temperature.        276     order of increasing color temperature.
277                                                   277 
278 .. tabularcolumns:: |p{7.4cm}|p{10.1cm}|          278 .. tabularcolumns:: |p{7.4cm}|p{10.1cm}|
279                                                   279 
280 .. flat-table::                                   280 .. flat-table::
281     :header-rows:  0                              281     :header-rows:  0
282     :stub-columns: 0                              282     :stub-columns: 0
283                                                   283 
284     * - ``V4L2_WHITE_BALANCE_MANUAL``             284     * - ``V4L2_WHITE_BALANCE_MANUAL``
285       - Manual white balance.                     285       - Manual white balance.
286     * - ``V4L2_WHITE_BALANCE_AUTO``               286     * - ``V4L2_WHITE_BALANCE_AUTO``
287       - Automatic white balance adjustments.      287       - Automatic white balance adjustments.
288     * - ``V4L2_WHITE_BALANCE_INCANDESCENT``       288     * - ``V4L2_WHITE_BALANCE_INCANDESCENT``
289       - White balance setting for incandescent    289       - White balance setting for incandescent (tungsten) lighting. It
290         generally cools down the colors and co    290         generally cools down the colors and corresponds approximately to
291         2500...3500 K color temperature range.    291         2500...3500 K color temperature range.
292     * - ``V4L2_WHITE_BALANCE_FLUORESCENT``        292     * - ``V4L2_WHITE_BALANCE_FLUORESCENT``
293       - White balance preset for fluorescent l    293       - White balance preset for fluorescent lighting. It corresponds
294         approximately to 4000...5000 K color t    294         approximately to 4000...5000 K color temperature.
295     * - ``V4L2_WHITE_BALANCE_FLUORESCENT_H``      295     * - ``V4L2_WHITE_BALANCE_FLUORESCENT_H``
296       - With this setting the camera will comp    296       - With this setting the camera will compensate for fluorescent H
297         lighting.                                 297         lighting.
298     * - ``V4L2_WHITE_BALANCE_HORIZON``            298     * - ``V4L2_WHITE_BALANCE_HORIZON``
299       - White balance setting for horizon dayl    299       - White balance setting for horizon daylight. It corresponds
300         approximately to 5000 K color temperat    300         approximately to 5000 K color temperature.
301     * - ``V4L2_WHITE_BALANCE_DAYLIGHT``           301     * - ``V4L2_WHITE_BALANCE_DAYLIGHT``
302       - White balance preset for daylight (wit    302       - White balance preset for daylight (with clear sky). It corresponds
303         approximately to 5000...6500 K color t    303         approximately to 5000...6500 K color temperature.
304     * - ``V4L2_WHITE_BALANCE_FLASH``              304     * - ``V4L2_WHITE_BALANCE_FLASH``
305       - With this setting the camera will comp    305       - With this setting the camera will compensate for the flash light.
306         It slightly warms up the colors and co    306         It slightly warms up the colors and corresponds roughly to
307         5000...5500 K color temperature.          307         5000...5500 K color temperature.
308     * - ``V4L2_WHITE_BALANCE_CLOUDY``             308     * - ``V4L2_WHITE_BALANCE_CLOUDY``
309       - White balance preset for moderately ov    309       - White balance preset for moderately overcast sky. This option
310         corresponds approximately to 6500...80    310         corresponds approximately to 6500...8000 K color temperature
311         range.                                    311         range.
312     * - ``V4L2_WHITE_BALANCE_SHADE``              312     * - ``V4L2_WHITE_BALANCE_SHADE``
313       - White balance preset for shade or heav    313       - White balance preset for shade or heavily overcast sky. It
314         corresponds approximately to 9000...10    314         corresponds approximately to 9000...10000 K color temperature.
315                                                   315 
316                                                   316 
317                                                   317 
318 .. _v4l2-wide-dynamic-range:                      318 .. _v4l2-wide-dynamic-range:
319                                                   319 
320 ``V4L2_CID_WIDE_DYNAMIC_RANGE (boolean)``         320 ``V4L2_CID_WIDE_DYNAMIC_RANGE (boolean)``
321     Enables or disables the camera's wide dyna    321     Enables or disables the camera's wide dynamic range feature. This
322     feature allows to obtain clear images in s    322     feature allows to obtain clear images in situations where intensity
323     of the illumination varies significantly t    323     of the illumination varies significantly throughout the scene, i.e.
324     there are simultaneously very dark and ver    324     there are simultaneously very dark and very bright areas. It is most
325     commonly realized in cameras by combining     325     commonly realized in cameras by combining two subsequent frames with
326     different exposure times.  [#f1]_             326     different exposure times.  [#f1]_
327                                                   327 
328 .. _v4l2-image-stabilization:                     328 .. _v4l2-image-stabilization:
329                                                   329 
330 ``V4L2_CID_IMAGE_STABILIZATION (boolean)``        330 ``V4L2_CID_IMAGE_STABILIZATION (boolean)``
331     Enables or disables image stabilization.      331     Enables or disables image stabilization.
332                                                   332 
333 ``V4L2_CID_ISO_SENSITIVITY (integer menu)``       333 ``V4L2_CID_ISO_SENSITIVITY (integer menu)``
334     Determines ISO equivalent of an image sens    334     Determines ISO equivalent of an image sensor indicating the sensor's
335     sensitivity to light. The numbers are expr    335     sensitivity to light. The numbers are expressed in arithmetic scale,
336     as per :ref:`iso12232` standard, where dou    336     as per :ref:`iso12232` standard, where doubling the sensor
337     sensitivity is represented by doubling the    337     sensitivity is represented by doubling the numerical ISO value.
338     Applications should interpret the values a    338     Applications should interpret the values as standard ISO values
339     multiplied by 1000, e.g. control value 800    339     multiplied by 1000, e.g. control value 800 stands for ISO 0.8.
340     Drivers will usually support only a subset    340     Drivers will usually support only a subset of standard ISO values.
341     The effect of setting this control while t    341     The effect of setting this control while the
342     ``V4L2_CID_ISO_SENSITIVITY_AUTO`` control     342     ``V4L2_CID_ISO_SENSITIVITY_AUTO`` control is set to a value other
343     than ``V4L2_CID_ISO_SENSITIVITY_MANUAL`` i    343     than ``V4L2_CID_ISO_SENSITIVITY_MANUAL`` is undefined, drivers
344     should ignore such requests.                  344     should ignore such requests.
345                                                   345 
346 .. _v4l2-iso-sensitivity-auto-type:               346 .. _v4l2-iso-sensitivity-auto-type:
347                                                   347 
348 ``V4L2_CID_ISO_SENSITIVITY_AUTO``                 348 ``V4L2_CID_ISO_SENSITIVITY_AUTO``
349     (enum)                                        349     (enum)
350                                                   350 
351 enum v4l2_iso_sensitivity_type -                  351 enum v4l2_iso_sensitivity_type -
352     Enables or disables automatic ISO sensitiv    352     Enables or disables automatic ISO sensitivity adjustments.
353                                                   353 
354                                                   354 
355                                                   355 
356 .. flat-table::                                   356 .. flat-table::
357     :header-rows:  0                              357     :header-rows:  0
358     :stub-columns: 0                              358     :stub-columns: 0
359                                                   359 
360     * - ``V4L2_CID_ISO_SENSITIVITY_MANUAL``       360     * - ``V4L2_CID_ISO_SENSITIVITY_MANUAL``
361       - Manual ISO sensitivity.                   361       - Manual ISO sensitivity.
362     * - ``V4L2_CID_ISO_SENSITIVITY_AUTO``         362     * - ``V4L2_CID_ISO_SENSITIVITY_AUTO``
363       - Automatic ISO sensitivity adjustments.    363       - Automatic ISO sensitivity adjustments.
364                                                   364 
365                                                   365 
366                                                   366 
367 .. _v4l2-scene-mode:                              367 .. _v4l2-scene-mode:
368                                                   368 
369 ``V4L2_CID_SCENE_MODE``                           369 ``V4L2_CID_SCENE_MODE``
370     (enum)                                        370     (enum)
371                                                   371 
372 enum v4l2_scene_mode -                            372 enum v4l2_scene_mode -
373     This control allows to select scene progra    373     This control allows to select scene programs as the camera automatic
374     modes optimized for common shooting scenes    374     modes optimized for common shooting scenes. Within these modes the
375     camera determines best exposure, aperture,    375     camera determines best exposure, aperture, focusing, light metering,
376     white balance and equivalent sensitivity.     376     white balance and equivalent sensitivity. The controls of those
377     parameters are influenced by the scene mod    377     parameters are influenced by the scene mode control. An exact
378     behavior in each mode is subject to the ca    378     behavior in each mode is subject to the camera specification.
379                                                   379 
380     When the scene mode feature is not used, t    380     When the scene mode feature is not used, this control should be set
381     to ``V4L2_SCENE_MODE_NONE`` to make sure t    381     to ``V4L2_SCENE_MODE_NONE`` to make sure the other possibly related
382     controls are accessible. The following sce    382     controls are accessible. The following scene programs are defined:
383                                                   383 
384 .. raw:: latex                                    384 .. raw:: latex
385                                                   385 
386     \small                                        386     \small
387                                                   387 
388 .. tabularcolumns:: |p{5.9cm}|p{11.6cm}|          388 .. tabularcolumns:: |p{5.9cm}|p{11.6cm}|
389                                                   389 
390 .. cssclass:: longtable                           390 .. cssclass:: longtable
391                                                   391 
392 .. flat-table::                                   392 .. flat-table::
393     :header-rows:  0                              393     :header-rows:  0
394     :stub-columns: 0                              394     :stub-columns: 0
395                                                   395 
396     * - ``V4L2_SCENE_MODE_NONE``                  396     * - ``V4L2_SCENE_MODE_NONE``
397       - The scene mode feature is disabled.       397       - The scene mode feature is disabled.
398     * - ``V4L2_SCENE_MODE_BACKLIGHT``             398     * - ``V4L2_SCENE_MODE_BACKLIGHT``
399       - Backlight. Compensates for dark shadow    399       - Backlight. Compensates for dark shadows when light is coming from
400         behind a subject, also by automaticall    400         behind a subject, also by automatically turning on the flash.
401     * - ``V4L2_SCENE_MODE_BEACH_SNOW``            401     * - ``V4L2_SCENE_MODE_BEACH_SNOW``
402       - Beach and snow. This mode compensates     402       - Beach and snow. This mode compensates for all-white or bright
403         scenes, which tend to look gray and lo    403         scenes, which tend to look gray and low contrast, when camera's
404         automatic exposure is based on an aver    404         automatic exposure is based on an average scene brightness. To
405         compensate, this mode automatically sl    405         compensate, this mode automatically slightly overexposes the
406         frames. The white balance may also be     406         frames. The white balance may also be adjusted to compensate for
407         the fact that reflected snow looks blu    407         the fact that reflected snow looks bluish rather than white.
408     * - ``V4L2_SCENE_MODE_CANDLELIGHT``           408     * - ``V4L2_SCENE_MODE_CANDLELIGHT``
409       - Candle light. The camera generally rai    409       - Candle light. The camera generally raises the ISO sensitivity and
410         lowers the shutter speed. This mode co    410         lowers the shutter speed. This mode compensates for relatively
411         close subject in the scene. The flash     411         close subject in the scene. The flash is disabled in order to
412         preserve the ambiance of the light.       412         preserve the ambiance of the light.
413     * - ``V4L2_SCENE_MODE_DAWN_DUSK``             413     * - ``V4L2_SCENE_MODE_DAWN_DUSK``
414       - Dawn and dusk. Preserves the colors se    414       - Dawn and dusk. Preserves the colors seen in low natural light
415         before dusk and after down. The camera    415         before dusk and after down. The camera may turn off the flash, and
416         automatically focus at infinity. It wi    416         automatically focus at infinity. It will usually boost saturation
417         and lower the shutter speed.              417         and lower the shutter speed.
418     * - ``V4L2_SCENE_MODE_FALL_COLORS``           418     * - ``V4L2_SCENE_MODE_FALL_COLORS``
419       - Fall colors. Increases saturation and     419       - Fall colors. Increases saturation and adjusts white balance for
420         color enhancement. Pictures of autumn     420         color enhancement. Pictures of autumn leaves get saturated reds
421         and yellows.                              421         and yellows.
422     * - ``V4L2_SCENE_MODE_FIREWORKS``             422     * - ``V4L2_SCENE_MODE_FIREWORKS``
423       - Fireworks. Long exposure times are use    423       - Fireworks. Long exposure times are used to capture the expanding
424         burst of light from a firework. The ca    424         burst of light from a firework. The camera may invoke image
425         stabilization.                            425         stabilization.
426     * - ``V4L2_SCENE_MODE_LANDSCAPE``             426     * - ``V4L2_SCENE_MODE_LANDSCAPE``
427       - Landscape. The camera may choose a sma    427       - Landscape. The camera may choose a small aperture to provide deep
428         depth of field and long exposure durat    428         depth of field and long exposure duration to help capture detail
429         in dim light conditions. The focus is     429         in dim light conditions. The focus is fixed at infinity. Suitable
430         for distant and wide scenery.             430         for distant and wide scenery.
431     * - ``V4L2_SCENE_MODE_NIGHT``                 431     * - ``V4L2_SCENE_MODE_NIGHT``
432       - Night, also known as Night Landscape.     432       - Night, also known as Night Landscape. Designed for low light
433         conditions, it preserves detail in the    433         conditions, it preserves detail in the dark areas without blowing
434         out bright objects. The camera general    434         out bright objects. The camera generally sets itself to a
435         medium-to-high ISO sensitivity, with a    435         medium-to-high ISO sensitivity, with a relatively long exposure
436         time, and turns flash off. As such, th    436         time, and turns flash off. As such, there will be increased image
437         noise and the possibility of blurred i    437         noise and the possibility of blurred image.
438     * - ``V4L2_SCENE_MODE_PARTY_INDOOR``          438     * - ``V4L2_SCENE_MODE_PARTY_INDOOR``
439       - Party and indoor. Designed to capture     439       - Party and indoor. Designed to capture indoor scenes that are lit
440         by indoor background lighting as well     440         by indoor background lighting as well as the flash. The camera
441         usually increases ISO sensitivity, and    441         usually increases ISO sensitivity, and adjusts exposure for the
442         low light conditions.                     442         low light conditions.
443     * - ``V4L2_SCENE_MODE_PORTRAIT``              443     * - ``V4L2_SCENE_MODE_PORTRAIT``
444       - Portrait. The camera adjusts the apert    444       - Portrait. The camera adjusts the aperture so that the depth of
445         field is reduced, which helps to isola    445         field is reduced, which helps to isolate the subject against a
446         smooth background. Most cameras recogn    446         smooth background. Most cameras recognize the presence of faces in
447         the scene and focus on them. The color    447         the scene and focus on them. The color hue is adjusted to enhance
448         skin tones. The intensity of the flash    448         skin tones. The intensity of the flash is often reduced.
449     * - ``V4L2_SCENE_MODE_SPORTS``                449     * - ``V4L2_SCENE_MODE_SPORTS``
450       - Sports. Significantly increases ISO an    450       - Sports. Significantly increases ISO and uses a fast shutter speed
451         to freeze motion of rapidly-moving sub    451         to freeze motion of rapidly-moving subjects. Increased image noise
452         may be seen in this mode.                 452         may be seen in this mode.
453     * - ``V4L2_SCENE_MODE_SUNSET``                453     * - ``V4L2_SCENE_MODE_SUNSET``
454       - Sunset. Preserves deep hues seen in su    454       - Sunset. Preserves deep hues seen in sunsets and sunrises. It bumps
455         up the saturation.                        455         up the saturation.
456     * - ``V4L2_SCENE_MODE_TEXT``                  456     * - ``V4L2_SCENE_MODE_TEXT``
457       - Text. It applies extra contrast and sh    457       - Text. It applies extra contrast and sharpness, it is typically a
458         black-and-white mode optimized for rea    458         black-and-white mode optimized for readability. Automatic focus
459         may be switched to close-up mode and t    459         may be switched to close-up mode and this setting may also involve
460         some lens-distortion correction.          460         some lens-distortion correction.
461                                                   461 
462 .. raw:: latex                                    462 .. raw:: latex
463                                                   463 
464     \normalsize                                   464     \normalsize
465                                                   465 
466                                                   466 
467 ``V4L2_CID_3A_LOCK (bitmask)``                    467 ``V4L2_CID_3A_LOCK (bitmask)``
468     This control locks or unlocks the automati    468     This control locks or unlocks the automatic focus, exposure and
469     white balance. The automatic adjustments c    469     white balance. The automatic adjustments can be paused independently
470     by setting the corresponding lock bit to 1    470     by setting the corresponding lock bit to 1. The camera then retains
471     the settings until the lock bit is cleared    471     the settings until the lock bit is cleared. The following lock bits
472     are defined:                                  472     are defined:
473                                                   473 
474     When a given algorithm is not enabled, dri    474     When a given algorithm is not enabled, drivers should ignore
475     requests to lock it and should return no e    475     requests to lock it and should return no error. An example might be
476     an application setting bit ``V4L2_LOCK_WHI    476     an application setting bit ``V4L2_LOCK_WHITE_BALANCE`` when the
477     ``V4L2_CID_AUTO_WHITE_BALANCE`` control is    477     ``V4L2_CID_AUTO_WHITE_BALANCE`` control is set to ``FALSE``. The
478     value of this control may be changed by ex    478     value of this control may be changed by exposure, white balance or
479     focus controls.                               479     focus controls.
480                                                   480 
481                                                   481 
482                                                   482 
483 .. flat-table::                                   483 .. flat-table::
484     :header-rows:  0                              484     :header-rows:  0
485     :stub-columns: 0                              485     :stub-columns: 0
486                                                   486 
487     * - ``V4L2_LOCK_EXPOSURE``                    487     * - ``V4L2_LOCK_EXPOSURE``
488       - Automatic exposure adjustments lock.      488       - Automatic exposure adjustments lock.
489     * - ``V4L2_LOCK_WHITE_BALANCE``               489     * - ``V4L2_LOCK_WHITE_BALANCE``
490       - Automatic white balance adjustments lo    490       - Automatic white balance adjustments lock.
491     * - ``V4L2_LOCK_FOCUS``                       491     * - ``V4L2_LOCK_FOCUS``
492       - Automatic focus lock.                     492       - Automatic focus lock.
493                                                   493 
494                                                   494 
495                                                   495 
496 ``V4L2_CID_PAN_SPEED (integer)``                  496 ``V4L2_CID_PAN_SPEED (integer)``
497     This control turns the camera horizontally    497     This control turns the camera horizontally at the specific speed.
498     The unit is undefined. A positive value mo    498     The unit is undefined. A positive value moves the camera to the
499     right (clockwise when viewed from above),     499     right (clockwise when viewed from above), a negative value to the
500     left. A value of zero stops the motion if     500     left. A value of zero stops the motion if one is in progress and has
501     no effect otherwise.                          501     no effect otherwise.
502                                                   502 
503 ``V4L2_CID_TILT_SPEED (integer)``                 503 ``V4L2_CID_TILT_SPEED (integer)``
504     This control turns the camera vertically a    504     This control turns the camera vertically at the specified speed. The
505     unit is undefined. A positive value moves     505     unit is undefined. A positive value moves the camera up, a negative
506     value down. A value of zero stops the moti    506     value down. A value of zero stops the motion if one is in progress
507     and has no effect otherwise.                  507     and has no effect otherwise.
508                                                   508 
509 .. _v4l2-camera-sensor-orientation:               509 .. _v4l2-camera-sensor-orientation:
510                                                   510 
511 ``V4L2_CID_CAMERA_ORIENTATION (menu)``            511 ``V4L2_CID_CAMERA_ORIENTATION (menu)``
512     This read-only control describes the camer    512     This read-only control describes the camera orientation by reporting its
513     mounting position on the device where the     513     mounting position on the device where the camera is installed. The control
514     value is constant and not modifiable by so    514     value is constant and not modifiable by software. This control is
515     particularly meaningful for devices which     515     particularly meaningful for devices which have a well defined orientation,
516     such as phones, laptops and portable devic    516     such as phones, laptops and portable devices since the control is expressed
517     as a position relative to the device's int    517     as a position relative to the device's intended usage orientation. For
518     example, a camera installed on the user-fa    518     example, a camera installed on the user-facing side of a phone, a tablet or
519     a laptop device is said to be have ``V4L2_    519     a laptop device is said to be have ``V4L2_CAMERA_ORIENTATION_FRONT``
520     orientation, while a camera installed on t    520     orientation, while a camera installed on the opposite side of the front one
521     is said to be have ``V4L2_CAMERA_ORIENTATI    521     is said to be have ``V4L2_CAMERA_ORIENTATION_BACK`` orientation. Camera
522     sensors not directly attached to the devic    522     sensors not directly attached to the device, or attached in a way that
523     allows them to move freely, such as webcam    523     allows them to move freely, such as webcams and digital cameras, are said to
524     have the ``V4L2_CAMERA_ORIENTATION_EXTERNA    524     have the ``V4L2_CAMERA_ORIENTATION_EXTERNAL`` orientation.
525                                                   525 
526                                                   526 
527 .. tabularcolumns:: |p{7.7cm}|p{9.8cm}|           527 .. tabularcolumns:: |p{7.7cm}|p{9.8cm}|
528                                                   528 
529 .. flat-table::                                   529 .. flat-table::
530     :header-rows:  0                              530     :header-rows:  0
531     :stub-columns: 0                              531     :stub-columns: 0
532                                                   532 
533     * - ``V4L2_CAMERA_ORIENTATION_FRONT``         533     * - ``V4L2_CAMERA_ORIENTATION_FRONT``
534       - The camera is oriented towards the use    534       - The camera is oriented towards the user facing side of the device.
535     * - ``V4L2_CAMERA_ORIENTATION_BACK``          535     * - ``V4L2_CAMERA_ORIENTATION_BACK``
536       - The camera is oriented towards the bac    536       - The camera is oriented towards the back facing side of the device.
537     * - ``V4L2_CAMERA_ORIENTATION_EXTERNAL``      537     * - ``V4L2_CAMERA_ORIENTATION_EXTERNAL``
538       - The camera is not directly attached to    538       - The camera is not directly attached to the device and is freely movable.
539                                                   539 
540                                                   540 
541 .. _v4l2-camera-sensor-rotation:                  541 .. _v4l2-camera-sensor-rotation:
542                                                   542 
543 ``V4L2_CID_CAMERA_SENSOR_ROTATION (integer)``     543 ``V4L2_CID_CAMERA_SENSOR_ROTATION (integer)``
544     This read-only control describes the rotat    544     This read-only control describes the rotation correction in degrees in the
545     counter-clockwise direction to be applied     545     counter-clockwise direction to be applied to the captured images once
546     captured to memory to compensate for the c    546     captured to memory to compensate for the camera sensor mounting rotation.
547                                                   547 
548     For a precise definition of the sensor mou    548     For a precise definition of the sensor mounting rotation refer to the
549     extensive description of the 'rotation' pr    549     extensive description of the 'rotation' properties in the device tree
550     bindings file 'video-interfaces.txt'.         550     bindings file 'video-interfaces.txt'.
551                                                   551 
552     A few examples are below reported, using a    552     A few examples are below reported, using a shark swimming from left to
553     right in front of the user as the example     553     right in front of the user as the example scene to capture. ::
554                                                   554 
555                  0               X-axis           555                  0               X-axis
556                0 +----------------------------    556                0 +------------------------------------->
557                  !                                557                  !
558                  !                                558                  !
559                  !                                559                  !
560                  !           |\____)\___          560                  !           |\____)\___
561                  !           ) _____  __`<        561                  !           ) _____  __`<
562                  !           |/     )/            562                  !           |/     )/
563                  !                                563                  !
564                  !                                564                  !
565                  !                                565                  !
566                  V                                566                  V
567                Y-axis                             567                Y-axis
568                                                   568 
569     Example one - Webcam                          569     Example one - Webcam
570                                                   570 
571     Assuming you can bring your laptop with yo    571     Assuming you can bring your laptop with you while swimming with sharks,
572     the camera module of the laptop is install    572     the camera module of the laptop is installed on the user facing part of a
573     laptop screen casing, and is typically use    573     laptop screen casing, and is typically used for video calls. The captured
574     images are meant to be displayed in landsc    574     images are meant to be displayed in landscape mode (width > height) on the
575     laptop screen.                                575     laptop screen.
576                                                   576 
577     The camera is typically mounted upside-dow    577     The camera is typically mounted upside-down to compensate the lens optical
578     inversion effect. In this case the value o    578     inversion effect. In this case the value of the
579     V4L2_CID_CAMERA_SENSOR_ROTATION control is    579     V4L2_CID_CAMERA_SENSOR_ROTATION control is 0, no rotation is required to
580     display images correctly to the user.         580     display images correctly to the user.
581                                                   581 
582     If the camera sensor is not mounted upside    582     If the camera sensor is not mounted upside-down it is required to compensate
583     the lens optical inversion effect and the     583     the lens optical inversion effect and the value of the
584     V4L2_CID_CAMERA_SENSOR_ROTATION control is    584     V4L2_CID_CAMERA_SENSOR_ROTATION control is 180 degrees, as images will
585     result rotated when captured to memory. ::    585     result rotated when captured to memory. ::
586                                                   586 
587                  +----------------------------    587                  +--------------------------------------+
588                  !                                588                  !                                      !
589                  !                                589                  !                                      !
590                  !                                590                  !                                      !
591                  !              __/(_____/|       591                  !              __/(_____/|             !
592                  !            >.___  ____ (       592                  !            >.___  ____ (             !
593                  !                 \(    \|       593                  !                 \(    \|             !
594                  !                                594                  !                                      !
595                  !                                595                  !                                      !
596                  !                                596                  !                                      !
597                  +----------------------------    597                  +--------------------------------------+
598                                                   598 
599     A software rotation correction of 180 degr    599     A software rotation correction of 180 degrees has to be applied to correctly
600     display the image on the user screen. ::      600     display the image on the user screen. ::
601                                                   601 
602                  +----------------------------    602                  +--------------------------------------+
603                  !                                603                  !                                      !
604                  !                                604                  !                                      !
605                  !                                605                  !                                      !
606                  !             |\____)\___        606                  !             |\____)\___              !
607                  !             ) _____  __`<      607                  !             ) _____  __`<            !
608                  !             |/     )/          608                  !             |/     )/                !
609                  !                                609                  !                                      !
610                  !                                610                  !                                      !
611                  !                                611                  !                                      !
612                  +----------------------------    612                  +--------------------------------------+
613                                                   613 
614     Example two - Phone camera                    614     Example two - Phone camera
615                                                   615 
616     It is more handy to go and swim with shark    616     It is more handy to go and swim with sharks with only your mobile phone
617     with you and take pictures with the camera    617     with you and take pictures with the camera that is installed on the back
618     side of the device, facing away from the u    618     side of the device, facing away from the user. The captured images are meant
619     to be displayed in portrait mode (height >    619     to be displayed in portrait mode (height > width) to match the device screen
620     orientation and the device usage orientati    620     orientation and the device usage orientation used when taking the picture.
621                                                   621 
622     The camera sensor is typically mounted wit    622     The camera sensor is typically mounted with its pixel array longer side
623     aligned to the device longer side, upside-    623     aligned to the device longer side, upside-down mounted to compensate for
624     the lens optical inversion effect.            624     the lens optical inversion effect.
625                                                   625 
626     The images once captured to memory will be    626     The images once captured to memory will be rotated and the value of the
627     V4L2_CID_CAMERA_SENSOR_ROTATION will repor    627     V4L2_CID_CAMERA_SENSOR_ROTATION will report a 90 degree rotation. ::
628                                                   628 
629                                                   629 
630                  +----------------------------    630                  +-------------------------------------+
631                  |                 _ _            631                  |                 _ _                 |
632                  |                \   /           632                  |                \   /                |
633                  |                 | |            633                  |                 | |                 |
634                  |                 | |            634                  |                 | |                 |
635                  |                 |  >           635                  |                 |  >                |
636                  |                <  |            636                  |                <  |                 |
637                  |                 | |            637                  |                 | |                 |
638                  |                   .            638                  |                   .                 |
639                  |                  V             639                  |                  V                  |
640                  +----------------------------    640                  +-------------------------------------+
641                                                   641 
642     A correction of 90 degrees in counter-cloc    642     A correction of 90 degrees in counter-clockwise direction has to be
643     applied to correctly display the image in     643     applied to correctly display the image in portrait mode on the device
644     screen. ::                                    644     screen. ::
645                                                   645 
646                           +-------------------    646                           +--------------------+
647                           |                       647                           |                    |
648                           |                       648                           |                    |
649                           |                       649                           |                    |
650                           |                       650                           |                    |
651                           |                       651                           |                    |
652                           |                       652                           |                    |
653                           |   |\____)\___         653                           |   |\____)\___      |
654                           |   ) _____  __`<       654                           |   ) _____  __`<    |
655                           |   |/     )/           655                           |   |/     )/        |
656                           |                       656                           |                    |
657                           |                       657                           |                    |
658                           |                       658                           |                    |
659                           |                       659                           |                    |
660                           |                       660                           |                    |
661                           +-------------------    661                           +--------------------+
662                                                   662 
663                                                   663 
664 .. [#f1]                                          664 .. [#f1]
665    This control may be changed to a menu contr    665    This control may be changed to a menu control in the future, if more
666    options are required.                          666    options are required.
667                                                   667 
668 ``V4L2_CID_HDR_SENSOR_MODE (menu)``               668 ``V4L2_CID_HDR_SENSOR_MODE (menu)``
669     Change the sensor HDR mode. A HDR picture     669     Change the sensor HDR mode. A HDR picture is obtained by merging two
670     captures of the same scene using two diffe    670     captures of the same scene using two different exposure periods. HDR mode
671     describes the way these two captures are m    671     describes the way these two captures are merged in the sensor.
672                                                   672 
673     As modes differ for each sensor, menu item    673     As modes differ for each sensor, menu items are not standardized by this
674     control and are left to the programmer.       674     control and are left to the programmer.
                                                      

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