Loop Restoration

Functions
void	av1_loop_restoration_filter_unit (const RestorationTileLimits *limits, const RestorationUnitInfo *rui, const RestorationStripeBoundaries *rsb, RestorationLineBuffers *rlbs, int plane_w, int plane_h, int ss_x, int ss_y, int highbd, int bit_depth, uint8_t *data8, int stride, uint8_t *dst8, int dst_stride, int32_t *tmpbuf, int optimized_lr, struct aom_internal_error_info *error_info)
	Function for applying loop restoration filter to a single unit.
void	av1_loop_restoration_filter_frame (YV12_BUFFER_CONFIG *frame, struct AV1Common *cm, int optimized_lr, void *lr_ctxt)
	Function for applying loop restoration filter to a frame.
void	av1_pick_filter_restoration (const YV12_BUFFER_CONFIG *sd, AV1_COMP *cpi)
	Algorithm for AV1 loop restoration search and estimation.

Detailed Description

This module describes the loop restoration search and estimation algorithm in AV1. More details will be added.

Function Documentation

av1_loop_restoration_filter_unit()

void av1_loop_restoration_filter_unit	(	const RestorationTileLimits *	limits,
		const RestorationUnitInfo *	rui,
		const RestorationStripeBoundaries *	rsb,
		RestorationLineBuffers *	rlbs,
		int	plane_w,
		int	plane_h,
		int	ss_x,
		int	ss_y,
		int	highbd,
		int	bit_depth,
		uint8_t *	data8,
		int	stride,
		uint8_t *	dst8,
		int	dst_stride,
		int32_t *	tmpbuf,
		int	optimized_lr,
		struct aom_internal_error_info *	error_info )

Function for applying loop restoration filter to a single unit.

This function applies the loop restoration filter to a single loop restoration unit.

Parameters

[in]	limits	Limits of the unit
[in]	rui	The parameters to use for this unit and its coefficients
[in]	rsb	Deblocked pixels to use for stripe boundaries
[in]	rlbs	Space to use as a scratch buffer
[in]	ss_x	Horizontal subsampling for plane
[in]	ss_y	Vertical subsampling for plane
[in]	plane_w	Width of the current plane
[in]	plane_h	Height of the current plane
[in]	highbd	Whether high bitdepth pipeline is used
[in]	bit_depth	Bit-depth of the video
[in]	data8	Frame data (pointing at the top-left corner of the frame, not the restoration unit).
[in]	stride	Stride of data8
[out]	dst8	Buffer where the results will be written. Like data8, dst8 should point at the top-left corner of the frame
[in]	dst_stride	Stride of dst8
[in]	tmpbuf	Scratch buffer used by the sgrproj filter which should be at least SGRPROJ_TMPBUF_SIZE big.
[in]	optimized_lr	Whether to use fast optimized Loop Restoration
[in,out]	error_info	Error info for reporting errors

Remarks

Nothing is returned. Instead, the filtered unit is output in dst8 at the proper restoration unit offset.

av1_loop_restoration_filter_frame()

void av1_loop_restoration_filter_frame	(	YV12_BUFFER_CONFIG *	frame,
		struct AV1Common *	cm,
		int	optimized_lr,
		void *	lr_ctxt )

Function for applying loop restoration filter to a frame.

This function applies the loop restoration filter to a frame.

Parameters

[in,out]	frame	Compressed frame buffer
[in,out]	cm	Pointer to top level common structure
[in]	optimized_lr	Whether to use fast optimized Loop Restoration
[in]	lr_ctxt	Loop restoration context

Remarks

Nothing is returned. Instead, the filtered frame is output in frame.

Referenced by cdef_restoration_frame().

av1_pick_filter_restoration()

void av1_pick_filter_restoration	(	const YV12_BUFFER_CONFIG *	sd,
		AV1_COMP *	cpi )

Algorithm for AV1 loop restoration search and estimation.

This function determines proper restoration filter types and associated parameters for each restoration unit in a frame.

Parameters

[in]	sd	Source frame buffer
[in,out]	cpi	Top-level encoder structure

Remarks

Nothing is returned. Instead, chosen restoration filter types and parameters are stored per plane in the rst_info structure of type RestorationInfo inside cpi->common:

• rst_info[ 0 ]: Chosen parameters for Y plane
• rst_info[ 1 ]: Chosen parameters for U plane if it exists
• rst_info[ 2 ]: Chosen parameters for V plane if it exists

The following fields in each rst_info[ p], p = 0, 1, 2 are populated:

• rst_info[ p ].frame_restoration_type
• rst_info[ p ].unit_info[ u ], for each u in 0, 1, ..., n( p ) - 1, where n( p ) is the number of restoration units in plane p.

The following fields in each rst_info[ p ].unit_info[ u ], p = 0, 1, 2 and u = 0, 1, ..., n( p ) - 1, of type RestorationUnitInfo are populated:

• rst_info[ p ].unit_info[ u ].restoration_type
• rst_info[ p ].unit_info[ u ].wiener_info OR rst_info[ p ].unit_info[ u ].sgrproj_info OR neither, depending on rst_info[ p ].unit_info[ u ].restoration_type

Referenced by cdef_restoration_frame().