diff options
author | Guennadi Liakhovetski <guennadi.liakhovetski@intel.com> | 2017-11-08 11:00:12 -0500 |
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committer | Tao Huang <huangtao@rock-chips.com> | 2018-07-05 18:27:39 +0800 |
commit | 8df73b298c9a1a5160dfd87a9b498ae3e31acc1c (patch) | |
tree | ba36cf188f2525798adbe5a530907990debeef12 /Documentation/media | |
parent | 31a4fbf74118728a6747e9e966b6a78dc45656f9 (diff) |
UPSTREAM: media: v4l: Add a UVC Metadata format
Add a pixel format, used by the UVC driver to stream metadata.
Conflicts:
Documentation/media/uapi/v4l/meta-formats.rst
drivers/media/v4l2-core/v4l2-ioctl.c
include/uapi/linux/videodev2.h
Change-Id: I979fd6b4d5d24510e47a1cfe525e8ae0a1a573ee
Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@intel.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: William Wu <william.wu@rock-chips.com>
(cherry picked from commit 563a01e1012dddbe120d1e1e1c466ea0639a098b)
Diffstat (limited to 'Documentation/media')
-rw-r--r-- | Documentation/media/uapi/v4l/meta-formats.rst | 15 | ||||
-rw-r--r-- | Documentation/media/uapi/v4l/pixfmt-meta-uvc.rst | 51 |
2 files changed, 66 insertions, 0 deletions
diff --git a/Documentation/media/uapi/v4l/meta-formats.rst b/Documentation/media/uapi/v4l/meta-formats.rst new file mode 100644 index 000000000000..386feadbd1c3 --- /dev/null +++ b/Documentation/media/uapi/v4l/meta-formats.rst @@ -0,0 +1,15 @@ +.. -*- coding: utf-8; mode: rst -*- + +.. _meta-formats: + +**************** +Metadata Formats +**************** + +These formats are used for the :ref:`metadata` interface only. + + +.. toctree:: + :maxdepth: 1 + + pixfmt-meta-uvc diff --git a/Documentation/media/uapi/v4l/pixfmt-meta-uvc.rst b/Documentation/media/uapi/v4l/pixfmt-meta-uvc.rst new file mode 100644 index 000000000000..b5165dc090c2 --- /dev/null +++ b/Documentation/media/uapi/v4l/pixfmt-meta-uvc.rst @@ -0,0 +1,51 @@ +.. -*- coding: utf-8; mode: rst -*- + +.. _v4l2-meta-fmt-uvc: + +******************************* +V4L2_META_FMT_UVC ('UVCH') +******************************* + +UVC Payload Header Data + + +Description +=========== + +This format describes standard UVC metadata, extracted from UVC packet headers +and provided by the UVC driver through metadata video nodes. That data includes +exact copies of the standard part of UVC Payload Header contents and auxiliary +timing information, required for precise interpretation of timestamps, contained +in those headers. See section "2.4.3.3 Video and Still Image Payload Headers" of +the "UVC 1.5 Class specification" for details. + +Each UVC payload header can be between 2 and 12 bytes large. Buffers can +contain multiple headers, if multiple such headers have been transmitted by the +camera for the respective frame. However, the driver may drop headers when the +buffer is full, when they contain no useful information (e.g. those without the +SCR field or with that field identical to the previous header), or generally to +perform rate limiting when the device sends a large number of headers. + +Each individual block contains the following fields: + +.. flat-table:: UVC Metadata Block + :widths: 1 4 + :header-rows: 1 + :stub-columns: 0 + + * - Field + - Description + * - __u64 ts; + - system timestamp in host byte order, measured by the driver upon + reception of the payload + * - __u16 sof; + - USB Frame Number in host byte order, also obtained by the driver as + close as possible to the above timestamp to enable correlation between + them + * - :cspan:`1` *The rest is an exact copy of the UVC payload header:* + * - __u8 length; + - length of the rest of the block, including this field + * - __u8 flags; + - Flags, indicating presence of other standard UVC fields + * - __u8 buf[]; + - The rest of the header, possibly including UVC PTS and SCR fields |