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+.. -*- coding: utf-8; mode: rst -*-
+
+.. _dv-timings:
+
+**************************
+Digital Video (DV) Timings
+**************************
+
+The video standards discussed so far have been dealing with Analog TV
+and the corresponding video timings. Today there are many more different
+hardware interfaces such as High Definition TV interfaces (HDMI), VGA,
+DVI connectors etc., that carry video signals and there is a need to
+extend the API to select the video timings for these interfaces. Since
+it is not possible to extend the :ref:`v4l2_std_id <v4l2-std-id>`
+due to the limited bits available, a new set of ioctls was added to
+set/get video timings at the input and output.
+
+These ioctls deal with the detailed digital video timings that define
+each video format. This includes parameters such as the active video
+width and height, signal polarities, frontporches, backporches, sync
+widths etc. The ``linux/v4l2-dv-timings.h`` header can be used to get
+the timings of the formats in the :ref:`cea861` and :ref:`vesadmt`
+standards.
+
+To enumerate and query the attributes of the DV timings supported by a
+device applications use the
+:ref:`VIDIOC_ENUM_DV_TIMINGS` and
+:ref:`VIDIOC_DV_TIMINGS_CAP` ioctls. To set
+DV timings for the device applications use the
+:ref:`VIDIOC_S_DV_TIMINGS <VIDIOC_G_DV_TIMINGS>` ioctl and to get
+current DV timings they use the
+:ref:`VIDIOC_G_DV_TIMINGS <VIDIOC_G_DV_TIMINGS>` ioctl. To detect
+the DV timings as seen by the video receiver applications use the
+:ref:`VIDIOC_QUERY_DV_TIMINGS` ioctl.
+
+Applications can make use of the :ref:`input-capabilities` and
+:ref:`output-capabilities` flags to determine whether the digital
+video ioctls can be used with the given input or output.