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diff --git a/Documentation/media/uapi/v4l/selection-api-intro.rst b/Documentation/media/uapi/v4l/selection-api-intro.rst deleted file mode 100644 index 0faed02d0226..000000000000 --- a/Documentation/media/uapi/v4l/selection-api-intro.rst +++ /dev/null @@ -1,35 +0,0 @@ -.. Permission is granted to copy, distribute and/or modify this -.. document under the terms of the GNU Free Documentation License, -.. Version 1.1 or any later version published by the Free Software -.. Foundation, with no Invariant Sections, no Front-Cover Texts -.. and no Back-Cover Texts. A copy of the license is included at -.. Documentation/media/uapi/fdl-appendix.rst. -.. -.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections - -************ -Introduction -************ - -Some video capture devices can sample a subsection of a picture and -shrink or enlarge it to an image of arbitrary size. Next, the devices -can insert the image into larger one. Some video output devices can crop -part of an input image, scale it up or down and insert it at an -arbitrary scan line and horizontal offset into a video signal. We call -these abilities cropping, scaling and composing. - -On a video *capture* device the source is a video signal, and the -cropping target determine the area actually sampled. The sink is an -image stored in a memory buffer. The composing area specifies which part -of the buffer is actually written to by the hardware. - -On a video *output* device the source is an image in a memory buffer, -and the cropping target is a part of an image to be shown on a display. -The sink is the display or the graphics screen. The application may -select the part of display where the image should be displayed. The size -and position of such a window is controlled by the compose target. - -Rectangles for all cropping and composing targets are defined even if -the device does supports neither cropping nor composing. Their size and -position will be fixed in such a case. If the device does not support -scaling then the cropping and composing rectangles have the same size. |