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+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+
+.. _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