media/v4l/dev-overlay.rst

20 files as :ref:`video capture <capture>` devices.
26    the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl.
47 :ref:`VIDIOC_QUERYCAP` ioctl. The overlay I/O
55 Video overlay devices shall support :ref:`audio input <audio>`,
56 :ref:`tuner`, :ref:`controls <control>`,
57 :ref:`cropping and scaling <crop>` and
58 :ref:`streaming parameter <streaming-par>` ioctls as needed. The
59 :ref:`video input <video>` and :ref:`video standard <standard>`
69 :ref:`VIDIOC_G_FBUF <VIDIOC_G_FBUF>` and
70 :ref:`VIDIOC_S_FBUF <VIDIOC_G_FBUF>` ioctls are available to get and
71 set these parameters, respectively. The :ref:`VIDIOC_S_FBUF <VIDIOC_G_FBUF>` ioctl is
82 driver. The :ref:`VIDIOC_S_FBUF <VIDIOC_G_FBUF>` ioctl is not privileged. An application
83 can check for this type of device by calling the :ref:`VIDIOC_G_FBUF <VIDIOC_G_FBUF>`
107 (:ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>`) or overlay
108 (:ref:`VIDIOC_S_FBUF <VIDIOC_G_FBUF>`) may fail with an ``EBUSY`` error
119 given in :ref:`crop`.
127 :ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>` ioctl. The driver fills the
134 call the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl. The driver
136 parameters as :ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>` does. Like :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>`, the
137 :ref:`VIDIOC_TRY_FMT <VIDIOC_G_FMT>` ioctl can be used to learn
139 :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` this also works after the overlay has been enabled.
143 of the cropping rectangle. For more information see :ref:`crop`.
148 (:ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>`) may fail with an ``EBUSY`` error
160     :ref:`VIDIOC_S_FBUF <VIDIOC_G_FBUF>`. The window can extend the
175     :ref:`VIDIOC_S_FBUF <VIDIOC_G_FBUF>` applications set this field
180     :ref:`V4L2_PIX_FMT_BGR24 <V4L2-PIX-FMT-BGR32>` the value should
185     :ref:`VIDIOC_G_FBUF <VIDIOC_G_FBUF>` indicated this capability,
196     contents after calling :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>`
203     after calling :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` are undefined. When clip lists are
208     :ref:`VIDIOC_G_FBUF <VIDIOC_G_FBUF>` indicated this capability,
224 its contents after calling :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` are
238     :ref:`VIDIOC_S_FBUF <VIDIOC_G_FBUF>`,
239     :ref:`framebuffer-flags`).
244    structure. However the :ref:`VIDIOC_[G|S|TRY]_FMT <VIDIOC_G_FMT>`
289 :ref:`VIDIOC_OVERLAY` ioctl.
293    :ref:`Xv/V4L <xvideo>` interface driver and a V4L2 application.