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-.. 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
-
-.. _selection-vs-crop:
-
-********************************
-Comparison with old cropping API
-********************************
-
-The selection API was introduced to cope with deficiencies of the
-older :ref:`CROP API <crop>`, that was designed to control simple
-capture devices. Later the cropping API was adopted by video output
-drivers. The ioctls are used to select a part of the display were the
-video signal is inserted. It should be considered as an API abuse
-because the described operation is actually the composing. The
-selection API makes a clear distinction between composing and cropping
-operations by setting the appropriate targets.
-
-The CROP API lacks any support for composing to and cropping from an
-image inside a memory buffer. The application could configure a
-capture device to fill only a part of an image by abusing V4L2
-API. Cropping a smaller image from a larger one is achieved by setting
-the field ``bytesperline`` at struct :c:type:`v4l2_pix_format`.
-Introducing an image offsets could be done by modifying field
-``m_userptr`` at struct :c:type:`v4l2_buffer` before calling
-:ref:`VIDIOC_QBUF <VIDIOC_QBUF>`. Those operations should be avoided
-because they are not portable (endianness), and do not work for
-macroblock and Bayer formats and mmap buffers.
-
-The selection API deals with configuration of buffer
-cropping/composing in a clear, intuitive and portable way. Next, with
-the selection API the concepts of the padded target and constraints
-flags are introduced. Finally, struct :c:type:`v4l2_crop` and struct
-:c:type:`v4l2_cropcap` have no reserved fields. Therefore there is no
-way to extend their functionality. The new struct
-:c:type:`v4l2_selection` provides a lot of place for future
-extensions.
-
-Driver developers are encouraged to implement only selection API. The
-former cropping API would be simulated using the new one.