av1/common/av1_loopfilter.h

/*
 * Copyright (c) 2016, Alliance for Open Media. All rights reserved
 *
 * This source code is subject to the terms of the BSD 2 Clause License and
 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
 * was not distributed with this source code in the LICENSE file, you can
 * obtain it at www.aomedia.org/license/software. If the Alliance for Open
 * Media Patent License 1.0 was not distributed with this source code in the
 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
 */

#ifndef AV1_COMMON_LOOPFILTER_H_
#define AV1_COMMON_LOOPFILTER_H_

#include "aom_ports/mem.h"
#include "./aom_config.h"

#include "av1/common/blockd.h"
#include "av1/common/seg_common.h"

#ifdef __cplusplus
extern "C" {
#endif

#define MAX_LOOP_FILTER 63
#define MAX_SHARPNESS 7

#define SIMD_WIDTH 16

enum lf_path {
  LF_PATH_420,
  LF_PATH_444,
  LF_PATH_SLOW,
};

#if LOOP_FILTER_BITMASK
typedef struct {
  uint64_t bits[4];
} FilterMaskY;

typedef uint64_t FilterMaskUV;

// This structure holds bit masks for all 4x4 blocks in a 64x64 region.
// Each 1 bit represents a position in which we want to apply the loop filter.
// For Y plane, 4x4 in 64x64 requires 16x16 = 256 bit, therefore we use 4
// uint64_t; For U, V plane, for 420 format, plane size is 32x32, thus we use
// a uint64_t to represent bitmask.
// Left_ entries refer to whether we apply a filter on the border to the
// left of the block.   Above_ entries refer to whether or not to apply a
// filter on the above border.
// Since each transform is accompanied by a potentially different type of
// loop filter there is a different entry in the array for each transform size.
typedef struct {
  FilterMaskY left_y[TX_SIZES];
  FilterMaskY above_y[TX_SIZES];
  FilterMaskUV left_u[TX_SIZES];
  FilterMaskUV above_u[TX_SIZES];
  FilterMaskUV left_v[TX_SIZES];
  FilterMaskUV above_v[TX_SIZES];

  // Y plane vertical edge and horizontal edge filter level
  uint8_t lfl_y_hor[MI_SIZE_64X64][MI_SIZE_64X64];
  uint8_t lfl_y_ver[MI_SIZE_64X64][MI_SIZE_64X64];

  // UV plane vertical edge and horizontal edge shares the same level
  uint8_t lfl_u[MI_SIZE_64X64 / 2][MI_SIZE_64X64 / 2];
  uint8_t lfl_v[MI_SIZE_64X64 / 2][MI_SIZE_64X64 / 2];
} LoopFilterMaskInfo;
// TODO(chengchen): remove old version of bitmask construction code once
// new bitmask is complete.

// Loopfilter bit mask per super block
#define LOOP_FILTER_MASK_NUM 4
typedef struct {
  LoopFilterMaskInfo lfm_info[LOOP_FILTER_MASK_NUM];
  int is_setup;
} LoopFilterMask;

// To determine whether to apply loop filtering at one transform block edge,
// we need information of the neighboring transform block. Specifically,
// in determining a vertical edge, we need the information of the tx block
// to its left. For a horizontal edge, we need info of the tx block above it.
// Thus, we need to record info of right column and bottom row of tx blocks.
// We record the information of the neighboring superblock, when bitmask
// building for a superblock is finished. And it will be used for next
// superblock bitmask building.
// Information includes:
// ------------------------------------------------------------
//                    MI_SIZE_64X64
// Y  tx_size above |--------------|
// Y  tx_size left  |--------------|
// UV tx_size above |--------------|
// UV tx_size left  |--------------|
// Y level above    |--------------|
// Y level left     |--------------|
// U level above    |--------------|
// U level left     |--------------|
// V level above    |--------------|
// V level left     |--------------|
// skip             |--------------|
// ------------------------------------------------------------
typedef struct {
  TX_SIZE tx_size_y_above[MI_SIZE_64X64];
  TX_SIZE tx_size_y_left[MI_SIZE_64X64];
  TX_SIZE tx_size_uv_above[MI_SIZE_64X64];
  TX_SIZE tx_size_uv_left[MI_SIZE_64X64];
  uint8_t y_level_above[MI_SIZE_64X64];
  uint8_t y_level_left[MI_SIZE_64X64];
  uint8_t u_level_above[MI_SIZE_64X64];
  uint8_t u_level_left[MI_SIZE_64X64];
  uint8_t v_level_above[MI_SIZE_64X64];
  uint8_t v_level_left[MI_SIZE_64X64];
  uint8_t skip[MI_SIZE_64X64];
} LpfSuperblockInfo;
#endif  // LOOP_FILTER_BITMASK

struct loopfilter {
  int filter_level[2];
  int filter_level_u;
  int filter_level_v;

  int sharpness_level;

  uint8_t mode_ref_delta_enabled;
  uint8_t mode_ref_delta_update;

  // 0 = Intra, Last, Last2+Last3,
  // GF, BRF, ARF2, ARF
  int8_t ref_deltas[REF_FRAMES];

  // 0 = ZERO_MV, MV
  int8_t mode_deltas[MAX_MODE_LF_DELTAS];

#if LOOP_FILTER_BITMASK
  LoopFilterMask *lfm;
  size_t lfm_num;
  int lfm_stride;
  LpfSuperblockInfo neighbor_sb_lpf_info;
#endif  // LOOP_FILTER_BITMASK
};

// Need to align this structure so when it is declared and
// passed it can be loaded into vector registers.
typedef struct {
  DECLARE_ALIGNED(SIMD_WIDTH, uint8_t, mblim[SIMD_WIDTH]);
  DECLARE_ALIGNED(SIMD_WIDTH, uint8_t, lim[SIMD_WIDTH]);
  DECLARE_ALIGNED(SIMD_WIDTH, uint8_t, hev_thr[SIMD_WIDTH]);
} loop_filter_thresh;

typedef struct {
  loop_filter_thresh lfthr[MAX_LOOP_FILTER + 1];
  uint8_t lvl[MAX_SEGMENTS][2][REF_FRAMES][MAX_MODE_LF_DELTAS];
} loop_filter_info_n;

// This structure holds bit masks for all 8x8 blocks in a 64x64 region.
// Each 1 bit represents a position in which we want to apply the loop filter.
// Left_ entries refer to whether we apply a filter on the border to the
// left of the block.   Above_ entries refer to whether or not to apply a
// filter on the above border.   Int_ entries refer to whether or not to
// apply borders on the 4x4 edges within the 8x8 block that each bit
// represents.
// Since each transform is accompanied by a potentially different type of
// loop filter there is a different entry in the array for each transform size.
typedef struct {
  uint64_t left_y[TX_SIZES];
  uint64_t above_y[TX_SIZES];
  uint64_t int_4x4_y;
  uint16_t left_uv[TX_SIZES];
  uint16_t above_uv[TX_SIZES];
  uint16_t left_int_4x4_uv;
  uint16_t above_int_4x4_uv;
  uint8_t lfl_y[MAX_MIB_SIZE][MAX_MIB_SIZE];
  uint8_t lfl_uv[MAX_MIB_SIZE / 2][MAX_MIB_SIZE / 2];
} LOOP_FILTER_MASK;

/* assorted loopfilter functions which get used elsewhere */
struct AV1Common;
struct macroblockd;
struct AV1LfSyncData;

// This function sets up the bit masks for the entire 64x64 region represented
// by mi_row, mi_col.
void av1_setup_mask(struct AV1Common *const cm, int mi_row, int mi_col,
                    MB_MODE_INFO **mi_8x8, int mode_info_stride,
                    LOOP_FILTER_MASK *lfm);

void av1_loop_filter_init(struct AV1Common *cm);

// Update the loop filter for the current frame.
// This should be called before av1_loop_filter_rows(),
// av1_loop_filter_frame()
// calls this function directly.
void av1_loop_filter_frame_init(struct AV1Common *cm, int default_filt_lvl,
                                int default_filt_lvl_r, int plane);

void av1_loop_filter_frame(YV12_BUFFER_CONFIG *frame, struct AV1Common *cm,
                           struct macroblockd *mbd, int filter_level,
                           int filter_level_r, int plane, int partial_frame);

// Apply the loop filter to [start, stop) macro block rows in frame_buffer.
void av1_loop_filter_rows(YV12_BUFFER_CONFIG *frame_buffer,
                          struct AV1Common *cm,
                          struct macroblockd_plane *planes, int start, int stop,
                          int y_only);

typedef struct LoopFilterWorkerData {
  YV12_BUFFER_CONFIG *frame_buffer;
  struct AV1Common *cm;
  struct macroblockd_plane planes[MAX_MB_PLANE];

  int start;
  int stop;
  int y_only;
} LFWorkerData;

#ifdef __cplusplus
}  // extern "C"
#endif

#endif  // AV1_COMMON_LOOPFILTER_H_