media: uapi: h264: Clean slice invariants syntax elements
The H.264 specification requires in section 7.4.3 "Slice header semantics", that the following values shall be the same in all slice headers: pic_parameter_set_id frame_num field_pic_flag bottom_field_flag idr_pic_id pic_order_cnt_lsb delta_pic_order_cnt_bottom delta_pic_order_cnt[ 0 ] delta_pic_order_cnt[ 1 ] sp_for_switch_flag slice_group_change_cycle These bitstream fields are part of the slice header, and therefore passed redundantly on each slice. The purpose of the redundancy is to make the codec fault-tolerant in network scenarios. This is of course not needed to be reflected in the V4L2 controls, given the bitstream has already been parsed by applications. Therefore, move the redundant fields to the per-frame decode parameters control (DECODE_PARAMS). Field 'pic_parameter_set_id' is simply removed in this case, because the PPS control must currently contain the active PPS. Syntax elements dec_ref_pic_marking() and those related to pic order count, remain invariant as well, and therefore, the fields dec_ref_pic_marking_bit_size and pic_order_cnt_bit_size are also common to all slices. Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com> Reviewed-by: Nicolas Dufresne <nicolas.dufresne@collabora.com> Tested-by: Jonas Karlman <jonas@kwiboo.se> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
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