Re: [PATCH v5 16/17] media: uapi: Change data_bit_offset definition

[Sebastian Fricke]

On 07.04.2022 17:29, Benjamin Gaignard wrote:
> 'F.7.3.6.1 General slice segment header syntax' section of HEVC
> specification describes that a slice header always end byte aligned,

s/always end byte aligned/always aligns on the end-byte/
or
s/always end byte aligned/always aligns on the last byte/
?

> therefore we only need to provide the data offset in byte.

s/byte/bytes/

Greetings,
Sebastian

> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxxxxx>
> ---
> version 5:
> - Fix numbers of bits computation in cedrus_h265_skip_bits() parameters
> Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst | 4 ++--
> drivers/staging/media/sunxi/cedrus/cedrus_h265.c          | 2 +-
> include/media/hevc-ctrls.h                                | 4 ++--
> 3 files changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
> index a3b1a063deba..48b3f533bc17 100644
> --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
> +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
> @@ -2986,8 +2986,8 @@ enum v4l2_mpeg_video_hevc_size_of_length_field -
>       - ``bit_size``
>       - Size (in bits) of the current slice data.
>     * - __u32
> -      - ``data_bit_offset``
> -      - Offset (in bits) to the video data in the current slice data.
> +      - ``data_byte_offset``
> +      - Offset (in bytes) to the video data in the current slice data.
>     * - __u32
>       - ``num_entry_point_offsets``
>       - Specifies the number of entry point offset syntax elements in the slice header.
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_h265.c b/drivers/staging/media/sunxi/cedrus/cedrus_h265.c
> index d04521ffd920..4f31f2f3b745 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus_h265.c
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus_h265.c
> @@ -405,7 +405,7 @@ static void cedrus_h265_setup(struct cedrus_ctx *ctx,
> 	/* Initialize bitstream access. */
> 	cedrus_write(dev, VE_DEC_H265_TRIGGER, VE_DEC_H265_TRIGGER_INIT_SWDEC);
>
> -	cedrus_h265_skip_bits(dev, slice_params->data_bit_offset);
> +	cedrus_h265_skip_bits(dev, slice_params->data_byte_offset * 8);
>
> 	/* Bitstream parameters. */
>
> diff --git a/include/media/hevc-ctrls.h b/include/media/hevc-ctrls.h
> index e6cdd122726c..1834072c0a43 100644
> --- a/include/media/hevc-ctrls.h
> +++ b/include/media/hevc-ctrls.h
> @@ -310,7 +310,7 @@ struct v4l2_hevc_pred_weight_table {
>  * V4L2_CTRL_FLAG_DYNAMIC_ARRAY flag must be set when using it.
>  *
>  * @bit_size: size (in bits) of the current slice data
> - * @data_bit_offset: offset (in bits) to the video data in the current slice data
> + * @data_byte_offset: offset (in bytes) to the video data in the current slice data
>  * @num_entry_point_offsets: specifies the number of entry point offset syntax
>  *			     elements in the slice header.
>  * @nal_unit_type: specifies the coding type of the slice (B, P or I)
> @@ -354,7 +354,7 @@ struct v4l2_hevc_pred_weight_table {
>  */
> struct v4l2_ctrl_hevc_slice_params {
> 	__u32	bit_size;
> -	__u32	data_bit_offset;
> +	__u32	data_byte_offset;
> 	__u32	num_entry_point_offsets;
> 	/* ISO/IEC 23008-2, ITU-T Rec. H.265: NAL unit header */
> 	__u8	nal_unit_type;
> --
> 2.32.0