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| author | Sakari Ailus <sakari.ailus@linux.intel.com> | 2023-02-21 20:37:29 +0300 |
|---|---|---|
| committer | Hans Verkuil <hverkuil-cisco@xs4all.nl> | 2024-04-29 15:56:36 +0300 |
| commit | 89345c2a6ff9c48c5f1ea336e66e46dfc38a467a (patch) | |
| tree | d005233f365411e6db0dc6d846c15693180a69e3 /Documentation/userspace-api/media | |
| parent | 1d92152339587174363c3c9f7561de95646d5625 (diff) | |
| download | linux-89345c2a6ff9c48c5f1ea336e66e46dfc38a467a.tar.xz | |
media: v4l: Support line-based metadata capture
Many camera sensors, among other devices, transmit embedded data and image
data for each CSI-2 frame. This embedded data typically contains register
configuration of the sensor that has been used to capture the image data
of the same frame.
The embedded data is received by the CSI-2 receiver and has the same
properties as the image data, including that it is line based: it has
width, height and bytesperline (stride).
Add these fields to struct v4l2_meta_format and document them.
Also add V4L2_FMT_FLAG_META_LINE_BASED to tell a given format is
line-based i.e. these fields of struct v4l2_meta_format are valid for it.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Diffstat (limited to 'Documentation/userspace-api/media')
3 files changed, 29 insertions, 0 deletions
diff --git a/Documentation/userspace-api/media/v4l/dev-meta.rst b/Documentation/userspace-api/media/v4l/dev-meta.rst index 0e7e1ee1471a..5eee9ab60395 100644 --- a/Documentation/userspace-api/media/v4l/dev-meta.rst +++ b/Documentation/userspace-api/media/v4l/dev-meta.rst @@ -47,6 +47,12 @@ member of the ``fmt`` union as needed per the desired operation. Both drivers and applications must set the remainder of the :c:type:`v4l2_format` structure to 0. +Devices that capture metadata by line have the struct v4l2_fmtdesc +``V4L2_FMT_FLAG_META_LINE_BASED`` flag set for :c:func:`VIDIOC_ENUM_FMT`. Such +devices can typically also :ref:`capture image data <capture>`. This primarily +involves devices that receive the data from a different devices such as a camera +sensor. + .. c:type:: v4l2_meta_format .. tabularcolumns:: |p{1.4cm}|p{2.4cm}|p{13.5cm}| @@ -65,3 +71,18 @@ to 0. - ``buffersize`` - Maximum buffer size in bytes required for data. The value is set by the driver. + * - __u32 + - ``width`` + - Width of a line of metadata in Data Units. Valid when + :c:type`v4l2_fmtdesc` flag ``V4L2_FMT_FLAG_META_LINE_BASED`` is set, + otherwise zero. See :c:func:`VIDIOC_ENUM_FMT`. + * - __u32 + - ``height`` + - Number of rows of metadata. Valid when :c:type`v4l2_fmtdesc` flag + ``V4L2_FMT_FLAG_META_LINE_BASED`` is set, otherwise zero. See + :c:func:`VIDIOC_ENUM_FMT`. + * - __u32 + - ``bytesperline`` + - Offset in bytes between the beginning of two consecutive lines. Valid + when :c:type`v4l2_fmtdesc` flag ``V4L2_FMT_FLAG_META_LINE_BASED`` is + set, otherwise zero. See :c:func:`VIDIOC_ENUM_FMT`. diff --git a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst index 000c154b0f98..3adb3d205531 100644 --- a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst +++ b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst @@ -227,6 +227,13 @@ the ``mbus_code`` field is handled differently: The application can ask to configure the quantization of the capture device when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with :ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set. + * - ``V4L2_FMT_FLAG_META_LINE_BASED`` + - 0x0200 + - The metadata format is line-based. In this case the ``width``, + ``height`` and ``bytesperline`` fields of :c:type:`v4l2_meta_format` are + valid. The buffer consists of ``height`` lines, each having ``width`` + Data Units of data and the offset (in bytes) between the beginning of + each two consecutive lines is ``bytesperline``. Return Value ============ diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions index 3e58aac4ef0b..bdc628e8c1d6 100644 --- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions +++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions @@ -215,6 +215,7 @@ replace define V4L2_FMT_FLAG_CSC_XFER_FUNC fmtdesc-flags replace define V4L2_FMT_FLAG_CSC_YCBCR_ENC fmtdesc-flags replace define V4L2_FMT_FLAG_CSC_HSV_ENC fmtdesc-flags replace define V4L2_FMT_FLAG_CSC_QUANTIZATION fmtdesc-flags +replace define V4L2_FMT_FLAG_META_LINE_BASED fmtdesc-flags # V4L2 timecode types replace define V4L2_TC_TYPE_24FPS timecode-type |