xref: /OK3568_Linux_fs/kernel/Documentation/userspace-api/media/v4l/ext-ctrls-image-source.rst (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
2*4882a593Smuzhiyun
3*4882a593Smuzhiyun.. _image-source-controls:
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5*4882a593Smuzhiyun******************************
6*4882a593SmuzhiyunImage Source Control Reference
7*4882a593Smuzhiyun******************************
8*4882a593Smuzhiyun
9*4882a593SmuzhiyunThe Image Source control class is intended for low-level control of
10*4882a593Smuzhiyunimage source devices such as image sensors. The devices feature an
11*4882a593Smuzhiyunanalogue to digital converter and a bus transmitter to transmit the
12*4882a593Smuzhiyunimage data out of the device.
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14*4882a593Smuzhiyun
15*4882a593Smuzhiyun.. _image-source-control-id:
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17*4882a593SmuzhiyunImage Source Control IDs
18*4882a593Smuzhiyun========================
19*4882a593Smuzhiyun
20*4882a593Smuzhiyun``V4L2_CID_IMAGE_SOURCE_CLASS (class)``
21*4882a593Smuzhiyun    The IMAGE_SOURCE class descriptor.
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun``V4L2_CID_VBLANK (integer)``
24*4882a593Smuzhiyun    Vertical blanking. The idle period after every frame during which no
25*4882a593Smuzhiyun    image data is produced. The unit of vertical blanking is a line.
26*4882a593Smuzhiyun    Every line has length of the image width plus horizontal blanking at
27*4882a593Smuzhiyun    the pixel rate defined by ``V4L2_CID_PIXEL_RATE`` control in the
28*4882a593Smuzhiyun    same sub-device.
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun``V4L2_CID_HBLANK (integer)``
31*4882a593Smuzhiyun    Horizontal blanking. The idle period after every line of image data
32*4882a593Smuzhiyun    during which no image data is produced. The unit of horizontal
33*4882a593Smuzhiyun    blanking is pixels.
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun``V4L2_CID_ANALOGUE_GAIN (integer)``
36*4882a593Smuzhiyun    Analogue gain is gain affecting all colour components in the pixel
37*4882a593Smuzhiyun    matrix. The gain operation is performed in the analogue domain
38*4882a593Smuzhiyun    before A/D conversion.
39*4882a593Smuzhiyun
40*4882a593Smuzhiyun``V4L2_CID_TEST_PATTERN_RED (integer)``
41*4882a593Smuzhiyun    Test pattern red colour component.
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun``V4L2_CID_TEST_PATTERN_GREENR (integer)``
44*4882a593Smuzhiyun    Test pattern green (next to red) colour component.
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun``V4L2_CID_TEST_PATTERN_BLUE (integer)``
47*4882a593Smuzhiyun    Test pattern blue colour component.
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun``V4L2_CID_TEST_PATTERN_GREENB (integer)``
50*4882a593Smuzhiyun    Test pattern green (next to blue) colour component.
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun``V4L2_CID_UNIT_CELL_SIZE (struct)``
53*4882a593Smuzhiyun    This control returns the unit cell size in nanometers. The struct
54*4882a593Smuzhiyun    :c:type:`v4l2_area` provides the width and the height in separate
55*4882a593Smuzhiyun    fields to take into consideration asymmetric pixels.
56*4882a593Smuzhiyun    This control does not take into consideration any possible hardware
57*4882a593Smuzhiyun    binning.
58*4882a593Smuzhiyun    The unit cell consists of the whole area of the pixel, sensitive and
59*4882a593Smuzhiyun    non-sensitive.
60*4882a593Smuzhiyun    This control is required for automatic calibration of sensors/cameras.
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