On Tue, 15 Feb 2022 12:01:02 +0100, you wrote:
The number of 'entry point offset' could be very variable.If we are going to support multiple slice headers in a single control
Rather than use a large static array define a v4l2 dynamic array
of integer control.
The number of entry point offsets is reported by the elems field.
then we are going to need to know how to split these entries between
them as I assume that the entry point offset entries for all slice
headers would just be catenated here. You could add extra elements here
or generate a completely new control but I think it would be easier to
reinstate the num_entry_point_offsets field in the slice_params
structure (its a field that userpace has in its hand anyway so its no
effort for it to fill in). num_entry_point_offsets is a field that RPi
wants (without needing the entry points themselves) so that would help
me.
Regards
John Cox
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxxxxx>
---
version 2:
- Define a new CID for entry point offsets parameters
.../userspace-api/media/v4l/ext-ctrls-codec.rst | 9 +++++++++
include/uapi/linux/v4l2-controls.h | 1 +
2 files changed, 10 insertions(+)
diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
index c3ae97657fa7..679595e94643 100644
--- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
+++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
@@ -3101,6 +3101,15 @@ enum v4l2_mpeg_video_hevc_size_of_length_field -
\normalsize
+``V4L2_CID_STATELESS_HEVC_ENTRY_POINT_OFFSETS (integer)``
+ Specifies the i-th entry point offset in bytes and is represented by
+ offset_len_minus1 plus 1 bits.
+ This control is a dynamically sized array. The number of entry point
+ offsets is reported by the ``elems`` field.
+ This bitstream parameter is defined according to :ref:`hevc`.
+ They are described in section 7.4.7.1 "General slice segment header
+ semantics" of the specification.
+
``V4L2_CID_STATELESS_HEVC_SCALING_MATRIX (struct)``
Specifies the HEVC scaling matrix parameters used for the scaling process
for transform coefficients.
diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
index 27f5d272dc43..700e6cce958c 100644
--- a/include/uapi/linux/v4l2-controls.h
+++ b/include/uapi/linux/v4l2-controls.h
@@ -2314,6 +2314,7 @@ struct v4l2_ctrl_vp9_compressed_hdr {
#define V4L2_CID_STATELESS_HEVC_DECODE_PARAMS (V4L2_CID_CODEC_STATELESS_BASE + 404)
#define V4L2_CID_STATELESS_HEVC_DECODE_MODE (V4L2_CID_CODEC_STATELESS_BASE + 405)
#define V4L2_CID_STATELESS_HEVC_START_CODE (V4L2_CID_CODEC_STATELESS_BASE + 406)
+#define V4L2_CID_STATELESS_HEVC_ENTRY_POINT_OFFSET (V4L2_CID_CODEC_STATELESS_BASE + 407)
enum v4l2_stateless_hevc_decode_mode {
V4L2_STATELESS_HEVC_DECODE_MODE_SLICE_BASED,