diff options
Diffstat (limited to 'Documentation/media/uapi/v4l/vidioc-g-selection.rst')
| -rw-r--r-- | Documentation/media/uapi/v4l/vidioc-g-selection.rst | 26 |
1 files changed, 14 insertions, 12 deletions
diff --git a/Documentation/media/uapi/v4l/vidioc-g-selection.rst b/Documentation/media/uapi/v4l/vidioc-g-selection.rst index deb1f6fb473b..c1ee86472918 100644 --- a/Documentation/media/uapi/v4l/vidioc-g-selection.rst +++ b/Documentation/media/uapi/v4l/vidioc-g-selection.rst @@ -42,11 +42,7 @@ The ioctls are used to query and configure selection rectangles. To query the cropping (composing) rectangle set struct :c:type:`v4l2_selection` ``type`` field to the -respective buffer type. Do not use the multiplanar buffer types. Use -``V4L2_BUF_TYPE_VIDEO_CAPTURE`` instead of -``V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE`` and use -``V4L2_BUF_TYPE_VIDEO_OUTPUT`` instead of -``V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE``. The next step is setting the +respective buffer type. The next step is setting the value of struct :c:type:`v4l2_selection` ``target`` field to ``V4L2_SEL_TGT_CROP`` (``V4L2_SEL_TGT_COMPOSE``). Please refer to table :ref:`v4l2-selections-common` or :ref:`selection-api` for @@ -64,11 +60,7 @@ pixels. To change the cropping (composing) rectangle set the struct :c:type:`v4l2_selection` ``type`` field to the -respective buffer type. Do not use multiplanar buffers. Use -``V4L2_BUF_TYPE_VIDEO_CAPTURE`` instead of -``V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE``. Use -``V4L2_BUF_TYPE_VIDEO_OUTPUT`` instead of -``V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE``. The next step is setting the +respective buffer type. The next step is setting the value of struct :c:type:`v4l2_selection` ``target`` to ``V4L2_SEL_TGT_CROP`` (``V4L2_SEL_TGT_COMPOSE``). Please refer to table :ref:`v4l2-selections-common` or :ref:`selection-api` for additional @@ -129,8 +121,8 @@ Selection targets and flags are documented in .. _sel-const-adjust: -.. figure:: constraints.* - :alt: constraints.pdf / constraints.svg +.. kernel-figure:: constraints.svg + :alt: constraints.svg :align: center Size adjustments with constraint flags. @@ -169,6 +161,16 @@ Selection targets and flags are documented in - Reserved fields for future use. Drivers and applications must zero this array. +.. note:: + Unfortunately in the case of multiplanar buffer types + (``V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE`` and ``V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE``) + this API was messed up with regards to how the :c:type:`v4l2_selection` ``type`` field + should be filled in. Some drivers only accepted the ``_MPLANE`` buffer type while + other drivers only accepted a non-multiplanar buffer type (i.e. without the + ``_MPLANE`` at the end). + + Starting with kernel 4.13 both variations are allowed. + Return Value ============ |