Commit 471e5602 authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab
Browse files

doc-rst: dev-overlay: Fix conversion issues 



There were several conversion issues on this file, causing it
to be badly formatted. Fix them, in order to match the
design used on DocBook.

Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
parent 6fa26355

Documentation/linux_tv/media/v4l/dev-overlay.rst

+21 −24
Original line number Diff line number Diff line
@@ -6,8 +6,8 @@ 
Video Overlay Interface

***********************



**Also known as Framebuffer Overlay or Previewing.**



**Also known as Framebuffer Overlay or Previewing**

Video overlay devices have the ability to genlock (TV-)video into the

(VGA-)video signal of a graphics card, or to store captured images

directly in video memory of a graphics card, typically with clipping.
@@ -183,16 +183,14 @@ struct v4l2_window 
    applications can set this field to point to an array of clipping

    rectangles.



Like the window coordinates

w

, clipping rectangles are defined relative to the top, left corner of

the frame buffer. However clipping rectangles must not extend the frame

buffer width and height, and they must not overlap. If possible

applications should merge adjacent rectangles. Whether this must create

x-y or y-x bands, or the order of rectangles, is not defined. When clip

lists are not supported the driver ignores this field. Its contents

after calling

!ri!:ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>`

    Like the window coordinates w, clipping rectangles are defined

    relative to the top, left corner of the frame buffer. However

    clipping rectangles must not extend the frame buffer width and

    height, and they must not overlap. If possible applications

    should merge adjacent rectangles. Whether this must create

    x-y or y-x bands, or the order of rectangles, is not defined. When

    clip lists are not supported the driver ignores this field. Its

    contents after calling :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>`

    are undefined.



``__u32 clipcount``
@@ -237,30 +235,24 @@ exceeded are undefined. [3]_ 
    :ref:`VIDIOC_S_FBUF <VIDIOC_G_FBUF>`,

    :ref:`framebuffer-flags`).



Note this field was added in Linux 2.6.23, extending the structure.

However the

!ri!:ref:`VIDIOC_G/S/TRY_FMT <VIDIOC_G_FMT>`

ioctls, which take a pointer to a

!ri!:ref:`v4l2_format <v4l2-format>`

    **Note**: this field was added in Linux 2.6.23, extending the structure.

    However the :ref:`VIDIOC_[G|S|TRY]_FMT <VIDIOC_G_FMT>`

    ioctls, which take a pointer to a :ref:`v4l2_format <v4l2-format>`

    parent structure with padding bytes at the end, are not affected.





.. _v4l2-clip:



struct v4l2_clip

struct v4l2_clip [4]_

----------------



The X Window system defines "regions" which are vectors of struct BoxRec

{ short x1, y1, x2, y2; } with width = x2 - x1 and height = y2 - y1, so

one cannot pass X11 clip lists directly.



``struct v4l2_rect c``

    Coordinates of the clipping rectangle, relative to the top, left

    corner of the frame buffer. Only window pixels *outside* all

    clipping rectangles are displayed.



``struct v4l2_clip * next``

    Pointer to the next clipping rectangle, NULL when this is the last

    Pointer to the next clipping rectangle, ``NULL`` when this is the last

    rectangle. Drivers ignore this field, it cannot be used to pass a

    linked list of clipping rectangles.
@@ -317,3 +309,8 @@ To start or stop the frame buffer overlay applications call the 
   because the application and graphics system are not aware these

   regions need to be refreshed. The driver should clip out more pixels

   or not write the image at all.



.. [4]

   The X Window system defines "regions" which are vectors of ``struct

   BoxRec { short x1, y1, x2, y2; }`` with ``width = x2 - x1`` and

   ``height = y2 - y1``, so one cannot pass X11 clip lists directly.