av1/common/cfl.c - aom - Git at Google

 /*
  * 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.
  */

 #include "av1/common/cfl.h"
 #include "av1/common/common_data.h"
 #include "av1/common/onyxc_int.h"

 #include "config/av1_rtcd.h"

 void cfl_init(CFL_CTX *cfl, const SequenceHeader *seq_params) {
   assert(block_size_wide[CFL_MAX_BLOCK_SIZE] == CFL_BUF_LINE);
   assert(block_size_high[CFL_MAX_BLOCK_SIZE] == CFL_BUF_LINE);

   memset(&cfl->recon_buf_q3, 0, sizeof(cfl->recon_buf_q3));
   memset(&cfl->ac_buf_q3, 0, sizeof(cfl->ac_buf_q3));
   cfl->subsampling_x = seq_params->subsampling_x;
   cfl->subsampling_y = seq_params->subsampling_y;
   cfl->are_parameters_computed = 0;
   cfl->store_y = 0;
   // The DC_PRED cache is disabled by default and is only enabled in
   // cfl_rd_pick_alpha
   cfl->use_dc_pred_cache = 0;
   cfl->dc_pred_is_cached[CFL_PRED_U] = 0;
   cfl->dc_pred_is_cached[CFL_PRED_V] = 0;
 }

 void cfl_store_dc_pred(MACROBLOCKD *const xd, const uint8_t *input,
                        CFL_PRED_TYPE pred_plane, int width) {
   assert(pred_plane < CFL_PRED_PLANES);
   assert(width <= CFL_BUF_LINE);

   if (is_cur_buf_hbd(xd)) {
     uint16_t *const input_16 = CONVERT_TO_SHORTPTR(input);
     memcpy(xd->cfl.dc_pred_cache[pred_plane], input_16, width << 1);
     return;
   }

   memcpy(xd->cfl.dc_pred_cache[pred_plane], input, width);
 }

 static void cfl_load_dc_pred_lbd(const int16_t *dc_pred_cache, uint8_t *dst,
                                  int dst_stride, int width, int height) {
   for (int j = 0; j < height; j++) {
     memcpy(dst, dc_pred_cache, width);
     dst += dst_stride;
   }
 }

 static void cfl_load_dc_pred_hbd(const int16_t *dc_pred_cache, uint16_t *dst,
                                  int dst_stride, int width, int height) {
   const size_t num_bytes = width << 1;
   for (int j = 0; j < height; j++) {
     memcpy(dst, dc_pred_cache, num_bytes);
     dst += dst_stride;
   }
 }
 void cfl_load_dc_pred(MACROBLOCKD *const xd, uint8_t *dst, int dst_stride,
                       TX_SIZE tx_size, CFL_PRED_TYPE pred_plane) {
   const int width = tx_size_wide[tx_size];
   const int height = tx_size_high[tx_size];
   assert(pred_plane < CFL_PRED_PLANES);
   assert(width <= CFL_BUF_LINE);
   assert(height <= CFL_BUF_LINE);
   if (is_cur_buf_hbd(xd)) {
     uint16_t *dst_16 = CONVERT_TO_SHORTPTR(dst);
     cfl_load_dc_pred_hbd(xd->cfl.dc_pred_cache[pred_plane], dst_16, dst_stride,
                          width, height);
     return;
   }
   cfl_load_dc_pred_lbd(xd->cfl.dc_pred_cache[pred_plane], dst, dst_stride,
                        width, height);
 }

 // Due to frame boundary issues, it is possible that the total area covered by
 // chroma exceeds that of luma. When this happens, we fill the missing pixels by
 // repeating the last columns and/or rows.
 static INLINE void cfl_pad(CFL_CTX *cfl, int width, int height) {
   const int diff_width = width - cfl->buf_width;
   const int diff_height = height - cfl->buf_height;

   if (diff_width > 0) {
     const int min_height = height - diff_height;
     uint16_t *recon_buf_q3 = cfl->recon_buf_q3 + (width - diff_width);
     for (int j = 0; j < min_height; j++) {
       const uint16_t last_pixel = recon_buf_q3[-1];
       assert(recon_buf_q3 + diff_width <= cfl->recon_buf_q3 + CFL_BUF_SQUARE);
       for (int i = 0; i < diff_width; i++) {
         recon_buf_q3[i] = last_pixel;
       }
       recon_buf_q3 += CFL_BUF_LINE;
     }
     cfl->buf_width = width;
   }
   if (diff_height > 0) {
     uint16_t *recon_buf_q3 =
         cfl->recon_buf_q3 + ((height - diff_height) * CFL_BUF_LINE);
     for (int j = 0; j < diff_height; j++) {
       const uint16_t *last_row_q3 = recon_buf_q3 - CFL_BUF_LINE;
       assert(recon_buf_q3 + width <= cfl->recon_buf_q3 + CFL_BUF_SQUARE);
       for (int i = 0; i < width; i++) {
         recon_buf_q3[i] = last_row_q3[i];
       }
       recon_buf_q3 += CFL_BUF_LINE;
     }
     cfl->buf_height = height;
   }
 }

 static void subtract_average_c(const uint16_t *src, int16_t *dst, int width,
                                int height, int round_offset, int num_pel_log2) {
   int sum = round_offset;
   const uint16_t *recon = src;
   for (int j = 0; j < height; j++) {
     for (int i = 0; i < width; i++) {
       sum += recon[i];
     }
     recon += CFL_BUF_LINE;
   }
   const int avg = sum >> num_pel_log2;
   for (int j = 0; j < height; j++) {
     for (int i = 0; i < width; i++) {
       dst[i] = src[i] - avg;
     }
     src += CFL_BUF_LINE;
     dst += CFL_BUF_LINE;
   }
 }

 CFL_SUB_AVG_FN(c)

 static INLINE int cfl_idx_to_alpha(uint8_t alpha_idx, int8_t joint_sign,
                                    CFL_PRED_TYPE pred_type) {
   const int alpha_sign = (pred_type == CFL_PRED_U) ? CFL_SIGN_U(joint_sign)
                                                    : CFL_SIGN_V(joint_sign);
   if (alpha_sign == CFL_SIGN_ZERO) return 0;
   const int abs_alpha_q3 =
       (pred_type == CFL_PRED_U) ? CFL_IDX_U(alpha_idx) : CFL_IDX_V(alpha_idx);
   return (alpha_sign == CFL_SIGN_POS) ? abs_alpha_q3 + 1 : -abs_alpha_q3 - 1;
 }

 static INLINE void cfl_predict_lbd_c(const int16_t *ac_buf_q3, uint8_t *dst,
                                      int dst_stride, int alpha_q3, int width,
                                      int height) {
   for (int j = 0; j < height; j++) {
     for (int i = 0; i < width; i++) {
       dst[i] = clip_pixel(get_scaled_luma_q0(alpha_q3, ac_buf_q3[i]) + dst[i]);
     }
     dst += dst_stride;
     ac_buf_q3 += CFL_BUF_LINE;
   }
 }

 CFL_PREDICT_FN(c, lbd)

 #if CONFIG_AV1_HIGHBITDEPTH
 void cfl_predict_hbd_c(const int16_t *ac_buf_q3, uint16_t *dst, int dst_stride,
                        int alpha_q3, int bit_depth, int width, int height) {
   for (int j = 0; j < height; j++) {
     for (int i = 0; i < width; i++) {
       dst[i] = clip_pixel_highbd(
           get_scaled_luma_q0(alpha_q3, ac_buf_q3[i]) + dst[i], bit_depth);
     }
     dst += dst_stride;
     ac_buf_q3 += CFL_BUF_LINE;
   }
 }

 CFL_PREDICT_FN(c, hbd)
 #endif

 static void cfl_compute_parameters(MACROBLOCKD *const xd, TX_SIZE tx_size) {
   CFL_CTX *const cfl = &xd->cfl;
   // Do not call cfl_compute_parameters multiple time on the same values.
   assert(cfl->are_parameters_computed == 0);

   cfl_pad(cfl, tx_size_wide[tx_size], tx_size_high[tx_size]);
   cfl_get_subtract_average_fn(tx_size)(cfl->recon_buf_q3, cfl->ac_buf_q3);
   cfl->are_parameters_computed = 1;
 }

 void cfl_predict_block(MACROBLOCKD *const xd, uint8_t *dst, int dst_stride,
                        TX_SIZE tx_size, int plane) {
   CFL_CTX *const cfl = &xd->cfl;
   MB_MODE_INFO *mbmi = xd->mi[0];
   assert(is_cfl_allowed(xd));

   if (!cfl->are_parameters_computed) cfl_compute_parameters(xd, tx_size);

   const int alpha_q3 =
       cfl_idx_to_alpha(mbmi->cfl_alpha_idx, mbmi->cfl_alpha_signs, plane - 1);
   assert((tx_size_high[tx_size] - 1) * CFL_BUF_LINE + tx_size_wide[tx_size] <=
          CFL_BUF_SQUARE);
 #if CONFIG_AV1_HIGHBITDEPTH
   if (is_cur_buf_hbd(xd)) {
     uint16_t *dst_16 = CONVERT_TO_SHORTPTR(dst);
     cfl_get_predict_hbd_fn(tx_size)(cfl->ac_buf_q3, dst_16, dst_stride,
                                     alpha_q3, xd->bd);
     return;
   }
 #endif
   cfl_get_predict_lbd_fn(tx_size)(cfl->ac_buf_q3, dst, dst_stride, alpha_q3);
 }

 static void cfl_luma_subsampling_420_lbd_c(const uint8_t *input,
                                            int input_stride,
                                            uint16_t *output_q3, int width,
                                            int height) {
   for (int j = 0; j < height; j += 2) {
     for (int i = 0; i < width; i += 2) {
       const int bot = i + input_stride;
       output_q3[i >> 1] =
           (input[i] + input[i + 1] + input[bot] + input[bot + 1]) << 1;
     }
     input += input_stride << 1;
     output_q3 += CFL_BUF_LINE;
   }
 }

 static void cfl_luma_subsampling_422_lbd_c(const uint8_t *input,
                                            int input_stride,
                                            uint16_t *output_q3, int width,
                                            int height) {
   assert((height - 1) * CFL_BUF_LINE + width <= CFL_BUF_SQUARE);
   for (int j = 0; j < height; j++) {
     for (int i = 0; i < width; i += 2) {
       output_q3[i >> 1] = (input[i] + input[i + 1]) << 2;
     }
     input += input_stride;
     output_q3 += CFL_BUF_LINE;
   }
 }

 static void cfl_luma_subsampling_444_lbd_c(const uint8_t *input,
                                            int input_stride,
                                            uint16_t *output_q3, int width,
                                            int height) {
   assert((height - 1) * CFL_BUF_LINE + width <= CFL_BUF_SQUARE);
   for (int j = 0; j < height; j++) {
     for (int i = 0; i < width; i++) {
       output_q3[i] = input[i] << 3;
     }
     input += input_stride;
     output_q3 += CFL_BUF_LINE;
   }
 }

 #if CONFIG_AV1_HIGHBITDEPTH
 static void cfl_luma_subsampling_420_hbd_c(const uint16_t *input,
                                            int input_stride,
                                            uint16_t *output_q3, int width,
                                            int height) {
   for (int j = 0; j < height; j += 2) {
     for (int i = 0; i < width; i += 2) {
       const int bot = i + input_stride;
       output_q3[i >> 1] =
           (input[i] + input[i + 1] + input[bot] + input[bot + 1]) << 1;
     }
     input += input_stride << 1;
     output_q3 += CFL_BUF_LINE;
   }
 }

 static void cfl_luma_subsampling_422_hbd_c(const uint16_t *input,
                                            int input_stride,
                                            uint16_t *output_q3, int width,
                                            int height) {
   assert((height - 1) * CFL_BUF_LINE + width <= CFL_BUF_SQUARE);
   for (int j = 0; j < height; j++) {
     for (int i = 0; i < width; i += 2) {
       output_q3[i >> 1] = (input[i] + input[i + 1]) << 2;
     }
     input += input_stride;
     output_q3 += CFL_BUF_LINE;
   }
 }

 static void cfl_luma_subsampling_444_hbd_c(const uint16_t *input,
                                            int input_stride,
                                            uint16_t *output_q3, int width,
                                            int height) {
   assert((height - 1) * CFL_BUF_LINE + width <= CFL_BUF_SQUARE);
   for (int j = 0; j < height; j++) {
     for (int i = 0; i < width; i++) {
       output_q3[i] = input[i] << 3;
     }
     input += input_stride;
     output_q3 += CFL_BUF_LINE;
   }
 }
 #endif

 CFL_GET_SUBSAMPLE_FUNCTION(c)

 #if CONFIG_AV1_HIGHBITDEPTH
 static INLINE cfl_subsample_hbd_fn cfl_subsampling_hbd(TX_SIZE tx_size,
                                                        int sub_x, int sub_y) {
   if (sub_x == 1) {
     if (sub_y == 1) {
       return cfl_get_luma_subsampling_420_hbd(tx_size);
     }
     return cfl_get_luma_subsampling_422_hbd(tx_size);
   }
   return cfl_get_luma_subsampling_444_hbd(tx_size);
 }
 #endif

 static INLINE cfl_subsample_lbd_fn cfl_subsampling_lbd(TX_SIZE tx_size,
                                                        int sub_x, int sub_y) {
   if (sub_x == 1) {
     if (sub_y == 1) {
       return cfl_get_luma_subsampling_420_lbd(tx_size);
     }
     return cfl_get_luma_subsampling_422_lbd(tx_size);
   }
   return cfl_get_luma_subsampling_444_lbd(tx_size);
 }

 static void cfl_store(CFL_CTX *cfl, const uint8_t *input, int input_stride,
                       int row, int col, TX_SIZE tx_size, int use_hbd) {
   const int width = tx_size_wide[tx_size];
   const int height = tx_size_high[tx_size];
   const int tx_off_log2 = tx_size_wide_log2[0];
   const int sub_x = cfl->subsampling_x;
   const int sub_y = cfl->subsampling_y;
   const int store_row = row << (tx_off_log2 - sub_y);
   const int store_col = col << (tx_off_log2 - sub_x);
   const int store_height = height >> sub_y;
   const int store_width = width >> sub_x;

   // Invalidate current parameters
   cfl->are_parameters_computed = 0;

   // Store the surface of the pixel buffer that was written to, this way we
   // can manage chroma overrun (e.g. when the chroma surfaces goes beyond the
   // frame boundary)
   if (col == 0 && row == 0) {
     cfl->buf_width = store_width;
     cfl->buf_height = store_height;
   } else {
     cfl->buf_width = OD_MAXI(store_col + store_width, cfl->buf_width);
     cfl->buf_height = OD_MAXI(store_row + store_height, cfl->buf_height);
   }

   // Check that we will remain inside the pixel buffer.
   assert(store_row + store_height <= CFL_BUF_LINE);
   assert(store_col + store_width <= CFL_BUF_LINE);

   // Store the input into the CfL pixel buffer
   uint16_t *recon_buf_q3 =
       cfl->recon_buf_q3 + (store_row * CFL_BUF_LINE + store_col);
 #if CONFIG_AV1_HIGHBITDEPTH
   if (use_hbd) {
     cfl_subsampling_hbd(tx_size, sub_x, sub_y)(CONVERT_TO_SHORTPTR(input),
                                                input_stride, recon_buf_q3);
   } else {
     cfl_subsampling_lbd(tx_size, sub_x, sub_y)(input, input_stride,
                                                recon_buf_q3);
   }
 #else
   (void)use_hbd;
   cfl_subsampling_lbd(tx_size, sub_x, sub_y)(input, input_stride, recon_buf_q3);
 #endif
 }

 // Adjust the row and column of blocks smaller than 8X8, as chroma-referenced
 // and non-chroma-referenced blocks are stored together in the CfL buffer.
 static INLINE void sub8x8_adjust_offset(const CFL_CTX *cfl, int *row_out,
                                         int *col_out) {
   // Increment row index for bottom: 8x4, 16x4 or both bottom 4x4s.
   if ((cfl->mi_row & 0x01) && cfl->subsampling_y) {
     assert(*row_out == 0);
     (*row_out)++;
   }

   // Increment col index for right: 4x8, 4x16 or both right 4x4s.
   if ((cfl->mi_col & 0x01) && cfl->subsampling_x) {
     assert(*col_out == 0);
     (*col_out)++;
   }
 }

 void cfl_store_tx(MACROBLOCKD *const xd, int row, int col, TX_SIZE tx_size,
                   BLOCK_SIZE bsize) {
   CFL_CTX *const cfl = &xd->cfl;
   struct macroblockd_plane *const pd = &xd->plane[AOM_PLANE_Y];
   uint8_t *dst =
       &pd->dst.buf[(row * pd->dst.stride + col) << tx_size_wide_log2[0]];

   if (block_size_high[bsize] == 4 || block_size_wide[bsize] == 4) {
     // Only dimensions of size 4 can have an odd offset.
     assert(!((col & 1) && tx_size_wide[tx_size] != 4));
     assert(!((row & 1) && tx_size_high[tx_size] != 4));
     sub8x8_adjust_offset(cfl, &row, &col);
   }
   cfl_store(cfl, dst, pd->dst.stride, row, col, tx_size, is_cur_buf_hbd(xd));
 }

 void cfl_store_block(MACROBLOCKD *const xd, BLOCK_SIZE bsize, TX_SIZE tx_size) {
   CFL_CTX *const cfl = &xd->cfl;
   struct macroblockd_plane *const pd = &xd->plane[AOM_PLANE_Y];
   int row = 0;
   int col = 0;

   if (block_size_high[bsize] == 4 || block_size_wide[bsize] == 4) {
     sub8x8_adjust_offset(cfl, &row, &col);
   }
   const int width = max_intra_block_width(xd, bsize, AOM_PLANE_Y, tx_size);
   const int height = max_intra_block_height(xd, bsize, AOM_PLANE_Y, tx_size);
   tx_size = get_tx_size(width, height);
   cfl_store(cfl, pd->dst.buf, pd->dst.stride, row, col, tx_size,
             is_cur_buf_hbd(xd));
 }
	/*
	* 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.
	*/

	#include "av1/common/cfl.h"
	#include "av1/common/common_data.h"
	#include "av1/common/onyxc_int.h"

	#include "config/av1_rtcd.h"

	void cfl_init(CFL_CTX cfl, const SequenceHeader seq_params) {
	assert(block_size_wide[CFL_MAX_BLOCK_SIZE] == CFL_BUF_LINE);
	assert(block_size_high[CFL_MAX_BLOCK_SIZE] == CFL_BUF_LINE);

	memset(&cfl->recon_buf_q3, 0, sizeof(cfl->recon_buf_q3));
	memset(&cfl->ac_buf_q3, 0, sizeof(cfl->ac_buf_q3));
	cfl->subsampling_x = seq_params->subsampling_x;
	cfl->subsampling_y = seq_params->subsampling_y;
	cfl->are_parameters_computed = 0;
	cfl->store_y = 0;
	// The DC_PRED cache is disabled by default and is only enabled in
	// cfl_rd_pick_alpha
	cfl->use_dc_pred_cache = 0;
	cfl->dc_pred_is_cached[CFL_PRED_U] = 0;
	cfl->dc_pred_is_cached[CFL_PRED_V] = 0;
	}

	void cfl_store_dc_pred(MACROBLOCKD const xd, const uint8_t input,
	CFL_PRED_TYPE pred_plane, int width) {
	assert(pred_plane < CFL_PRED_PLANES);
	assert(width <= CFL_BUF_LINE);

	if (is_cur_buf_hbd(xd)) {
	uint16_t *const input_16 = CONVERT_TO_SHORTPTR(input);
	memcpy(xd->cfl.dc_pred_cache[pred_plane], input_16, width << 1);
	return;
	}

	memcpy(xd->cfl.dc_pred_cache[pred_plane], input, width);
	}

	static void cfl_load_dc_pred_lbd(const int16_t dc_pred_cache, uint8_t dst,
	int dst_stride, int width, int height) {
	for (int j = 0; j < height; j++) {
	memcpy(dst, dc_pred_cache, width);
	dst += dst_stride;
	}
	}

	static void cfl_load_dc_pred_hbd(const int16_t dc_pred_cache, uint16_t dst,
	int dst_stride, int width, int height) {
	const size_t num_bytes = width << 1;
	for (int j = 0; j < height; j++) {
	memcpy(dst, dc_pred_cache, num_bytes);
	dst += dst_stride;
	}
	}
	void cfl_load_dc_pred(MACROBLOCKD const xd, uint8_t dst, int dst_stride,
	TX_SIZE tx_size, CFL_PRED_TYPE pred_plane) {
	const int width = tx_size_wide[tx_size];
	const int height = tx_size_high[tx_size];
	assert(pred_plane < CFL_PRED_PLANES);
	assert(width <= CFL_BUF_LINE);
	assert(height <= CFL_BUF_LINE);
	if (is_cur_buf_hbd(xd)) {
	uint16_t *dst_16 = CONVERT_TO_SHORTPTR(dst);
	cfl_load_dc_pred_hbd(xd->cfl.dc_pred_cache[pred_plane], dst_16, dst_stride,
	width, height);
	return;
	}
	cfl_load_dc_pred_lbd(xd->cfl.dc_pred_cache[pred_plane], dst, dst_stride,
	width, height);
	}

	// Due to frame boundary issues, it is possible that the total area covered by
	// chroma exceeds that of luma. When this happens, we fill the missing pixels by
	// repeating the last columns and/or rows.
	static INLINE void cfl_pad(CFL_CTX *cfl, int width, int height) {
	const int diff_width = width - cfl->buf_width;
	const int diff_height = height - cfl->buf_height;

	if (diff_width > 0) {
	const int min_height = height - diff_height;
	uint16_t *recon_buf_q3 = cfl->recon_buf_q3 + (width - diff_width);
	for (int j = 0; j < min_height; j++) {
	const uint16_t last_pixel = recon_buf_q3[-1];
	assert(recon_buf_q3 + diff_width <= cfl->recon_buf_q3 + CFL_BUF_SQUARE);
	for (int i = 0; i < diff_width; i++) {
	recon_buf_q3[i] = last_pixel;
	}
	recon_buf_q3 += CFL_BUF_LINE;
	}
	cfl->buf_width = width;
	}
	if (diff_height > 0) {
	uint16_t *recon_buf_q3 =
	cfl->recon_buf_q3 + ((height - diff_height) * CFL_BUF_LINE);
	for (int j = 0; j < diff_height; j++) {
	const uint16_t *last_row_q3 = recon_buf_q3 - CFL_BUF_LINE;
	assert(recon_buf_q3 + width <= cfl->recon_buf_q3 + CFL_BUF_SQUARE);
	for (int i = 0; i < width; i++) {
	recon_buf_q3[i] = last_row_q3[i];
	}
	recon_buf_q3 += CFL_BUF_LINE;
	}
	cfl->buf_height = height;
	}
	}

	static void subtract_average_c(const uint16_t src, int16_t dst, int width,
	int height, int round_offset, int num_pel_log2) {
	int sum = round_offset;
	const uint16_t *recon = src;
	for (int j = 0; j < height; j++) {
	for (int i = 0; i < width; i++) {
	sum += recon[i];
	}
	recon += CFL_BUF_LINE;
	}
	const int avg = sum >> num_pel_log2;
	for (int j = 0; j < height; j++) {
	for (int i = 0; i < width; i++) {
	dst[i] = src[i] - avg;
	}
	src += CFL_BUF_LINE;
	dst += CFL_BUF_LINE;
	}
	}

	CFL_SUB_AVG_FN(c)

	static INLINE int cfl_idx_to_alpha(uint8_t alpha_idx, int8_t joint_sign,
	CFL_PRED_TYPE pred_type) {
	const int alpha_sign = (pred_type == CFL_PRED_U) ? CFL_SIGN_U(joint_sign)
	: CFL_SIGN_V(joint_sign);
	if (alpha_sign == CFL_SIGN_ZERO) return 0;
	const int abs_alpha_q3 =
	(pred_type == CFL_PRED_U) ? CFL_IDX_U(alpha_idx) : CFL_IDX_V(alpha_idx);
	return (alpha_sign == CFL_SIGN_POS) ? abs_alpha_q3 + 1 : -abs_alpha_q3 - 1;
	}

	static INLINE void cfl_predict_lbd_c(const int16_t ac_buf_q3, uint8_t dst,
	int dst_stride, int alpha_q3, int width,
	int height) {
	for (int j = 0; j < height; j++) {
	for (int i = 0; i < width; i++) {
	dst[i] = clip_pixel(get_scaled_luma_q0(alpha_q3, ac_buf_q3[i]) + dst[i]);
	}
	dst += dst_stride;
	ac_buf_q3 += CFL_BUF_LINE;
	}
	}

	CFL_PREDICT_FN(c, lbd)

	#if CONFIG_AV1_HIGHBITDEPTH
	void cfl_predict_hbd_c(const int16_t ac_buf_q3, uint16_t dst, int dst_stride,
	int alpha_q3, int bit_depth, int width, int height) {
	for (int j = 0; j < height; j++) {
	for (int i = 0; i < width; i++) {
	dst[i] = clip_pixel_highbd(
	get_scaled_luma_q0(alpha_q3, ac_buf_q3[i]) + dst[i], bit_depth);
	}
	dst += dst_stride;
	ac_buf_q3 += CFL_BUF_LINE;
	}
	}

	CFL_PREDICT_FN(c, hbd)
	#endif

	static void cfl_compute_parameters(MACROBLOCKD *const xd, TX_SIZE tx_size) {
	CFL_CTX *const cfl = &xd->cfl;
	// Do not call cfl_compute_parameters multiple time on the same values.
	assert(cfl->are_parameters_computed == 0);

	cfl_pad(cfl, tx_size_wide[tx_size], tx_size_high[tx_size]);
	cfl_get_subtract_average_fn(tx_size)(cfl->recon_buf_q3, cfl->ac_buf_q3);
	cfl->are_parameters_computed = 1;
	}

	void cfl_predict_block(MACROBLOCKD const xd, uint8_t dst, int dst_stride,
	TX_SIZE tx_size, int plane) {
	CFL_CTX *const cfl = &xd->cfl;
	MB_MODE_INFO *mbmi = xd->mi[0];
	assert(is_cfl_allowed(xd));

	if (!cfl->are_parameters_computed) cfl_compute_parameters(xd, tx_size);

	const int alpha_q3 =
	cfl_idx_to_alpha(mbmi->cfl_alpha_idx, mbmi->cfl_alpha_signs, plane - 1);
	assert((tx_size_high[tx_size] - 1) * CFL_BUF_LINE + tx_size_wide[tx_size] <=
	CFL_BUF_SQUARE);
	#if CONFIG_AV1_HIGHBITDEPTH
	if (is_cur_buf_hbd(xd)) {
	uint16_t *dst_16 = CONVERT_TO_SHORTPTR(dst);
	cfl_get_predict_hbd_fn(tx_size)(cfl->ac_buf_q3, dst_16, dst_stride,
	alpha_q3, xd->bd);
	return;
	}
	#endif
	cfl_get_predict_lbd_fn(tx_size)(cfl->ac_buf_q3, dst, dst_stride, alpha_q3);
	}

	static void cfl_luma_subsampling_420_lbd_c(const uint8_t *input,
	int input_stride,
	uint16_t *output_q3, int width,
	int height) {
	for (int j = 0; j < height; j += 2) {
	for (int i = 0; i < width; i += 2) {
	const int bot = i + input_stride;
	output_q3[i >> 1] =
	(input[i] + input[i + 1] + input[bot] + input[bot + 1]) << 1;
	}
	input += input_stride << 1;
	output_q3 += CFL_BUF_LINE;
	}
	}

	static void cfl_luma_subsampling_422_lbd_c(const uint8_t *input,
	int input_stride,
	uint16_t *output_q3, int width,
	int height) {
	assert((height - 1) * CFL_BUF_LINE + width <= CFL_BUF_SQUARE);
	for (int j = 0; j < height; j++) {
	for (int i = 0; i < width; i += 2) {
	output_q3[i >> 1] = (input[i] + input[i + 1]) << 2;
	}
	input += input_stride;
	output_q3 += CFL_BUF_LINE;
	}
	}

	static void cfl_luma_subsampling_444_lbd_c(const uint8_t *input,
	int input_stride,
	uint16_t *output_q3, int width,
	int height) {
	assert((height - 1) * CFL_BUF_LINE + width <= CFL_BUF_SQUARE);
	for (int j = 0; j < height; j++) {
	for (int i = 0; i < width; i++) {
	output_q3[i] = input[i] << 3;
	}
	input += input_stride;
	output_q3 += CFL_BUF_LINE;
	}
	}

	#if CONFIG_AV1_HIGHBITDEPTH
	static void cfl_luma_subsampling_420_hbd_c(const uint16_t *input,
	int input_stride,
	uint16_t *output_q3, int width,
	int height) {
	for (int j = 0; j < height; j += 2) {
	for (int i = 0; i < width; i += 2) {
	const int bot = i + input_stride;
	output_q3[i >> 1] =
	(input[i] + input[i + 1] + input[bot] + input[bot + 1]) << 1;
	}
	input += input_stride << 1;
	output_q3 += CFL_BUF_LINE;
	}
	}

	static void cfl_luma_subsampling_422_hbd_c(const uint16_t *input,
	int input_stride,
	uint16_t *output_q3, int width,
	int height) {
	assert((height - 1) * CFL_BUF_LINE + width <= CFL_BUF_SQUARE);
	for (int j = 0; j < height; j++) {
	for (int i = 0; i < width; i += 2) {
	output_q3[i >> 1] = (input[i] + input[i + 1]) << 2;
	}
	input += input_stride;
	output_q3 += CFL_BUF_LINE;
	}
	}

	static void cfl_luma_subsampling_444_hbd_c(const uint16_t *input,
	int input_stride,
	uint16_t *output_q3, int width,
	int height) {
	assert((height - 1) * CFL_BUF_LINE + width <= CFL_BUF_SQUARE);
	for (int j = 0; j < height; j++) {
	for (int i = 0; i < width; i++) {
	output_q3[i] = input[i] << 3;
	}
	input += input_stride;
	output_q3 += CFL_BUF_LINE;
	}
	}
	#endif

	CFL_GET_SUBSAMPLE_FUNCTION(c)

	#if CONFIG_AV1_HIGHBITDEPTH
	static INLINE cfl_subsample_hbd_fn cfl_subsampling_hbd(TX_SIZE tx_size,
	int sub_x, int sub_y) {
	if (sub_x == 1) {
	if (sub_y == 1) {
	return cfl_get_luma_subsampling_420_hbd(tx_size);
	}
	return cfl_get_luma_subsampling_422_hbd(tx_size);
	}
	return cfl_get_luma_subsampling_444_hbd(tx_size);
	}
	#endif

	static INLINE cfl_subsample_lbd_fn cfl_subsampling_lbd(TX_SIZE tx_size,
	int sub_x, int sub_y) {
	if (sub_x == 1) {
	if (sub_y == 1) {
	return cfl_get_luma_subsampling_420_lbd(tx_size);
	}
	return cfl_get_luma_subsampling_422_lbd(tx_size);
	}
	return cfl_get_luma_subsampling_444_lbd(tx_size);
	}

	static void cfl_store(CFL_CTX cfl, const uint8_t input, int input_stride,
	int row, int col, TX_SIZE tx_size, int use_hbd) {
	const int width = tx_size_wide[tx_size];
	const int height = tx_size_high[tx_size];
	const int tx_off_log2 = tx_size_wide_log2[0];
	const int sub_x = cfl->subsampling_x;
	const int sub_y = cfl->subsampling_y;
	const int store_row = row << (tx_off_log2 - sub_y);
	const int store_col = col << (tx_off_log2 - sub_x);
	const int store_height = height >> sub_y;
	const int store_width = width >> sub_x;

	// Invalidate current parameters
	cfl->are_parameters_computed = 0;

	// Store the surface of the pixel buffer that was written to, this way we
	// can manage chroma overrun (e.g. when the chroma surfaces goes beyond the
	// frame boundary)
	if (col == 0 && row == 0) {
	cfl->buf_width = store_width;
	cfl->buf_height = store_height;
	} else {
	cfl->buf_width = OD_MAXI(store_col + store_width, cfl->buf_width);
	cfl->buf_height = OD_MAXI(store_row + store_height, cfl->buf_height);
	}

	// Check that we will remain inside the pixel buffer.
	assert(store_row + store_height <= CFL_BUF_LINE);
	assert(store_col + store_width <= CFL_BUF_LINE);

	// Store the input into the CfL pixel buffer
	uint16_t *recon_buf_q3 =
	cfl->recon_buf_q3 + (store_row * CFL_BUF_LINE + store_col);
	#if CONFIG_AV1_HIGHBITDEPTH
	if (use_hbd) {
	cfl_subsampling_hbd(tx_size, sub_x, sub_y)(CONVERT_TO_SHORTPTR(input),
	input_stride, recon_buf_q3);
	} else {
	cfl_subsampling_lbd(tx_size, sub_x, sub_y)(input, input_stride,
	recon_buf_q3);
	}
	#else
	(void)use_hbd;
	cfl_subsampling_lbd(tx_size, sub_x, sub_y)(input, input_stride, recon_buf_q3);
	#endif
	}

	// Adjust the row and column of blocks smaller than 8X8, as chroma-referenced
	// and non-chroma-referenced blocks are stored together in the CfL buffer.
	static INLINE void sub8x8_adjust_offset(const CFL_CTX cfl, int row_out,
	int *col_out) {
	// Increment row index for bottom: 8x4, 16x4 or both bottom 4x4s.
	if ((cfl->mi_row & 0x01) && cfl->subsampling_y) {
	assert(*row_out == 0);
	(*row_out)++;
	}

	// Increment col index for right: 4x8, 4x16 or both right 4x4s.
	if ((cfl->mi_col & 0x01) && cfl->subsampling_x) {
	assert(*col_out == 0);
	(*col_out)++;
	}
	}

	void cfl_store_tx(MACROBLOCKD *const xd, int row, int col, TX_SIZE tx_size,
	BLOCK_SIZE bsize) {
	CFL_CTX *const cfl = &xd->cfl;
	struct macroblockd_plane *const pd = &xd->plane[AOM_PLANE_Y];
	uint8_t *dst =
	&pd->dst.buf[(row * pd->dst.stride + col) << tx_size_wide_log2[0]];

	if (block_size_high[bsize] == 4 \|\| block_size_wide[bsize] == 4) {
	// Only dimensions of size 4 can have an odd offset.
	assert(!((col & 1) && tx_size_wide[tx_size] != 4));
	assert(!((row & 1) && tx_size_high[tx_size] != 4));
	sub8x8_adjust_offset(cfl, &row, &col);
	}
	cfl_store(cfl, dst, pd->dst.stride, row, col, tx_size, is_cur_buf_hbd(xd));
	}

	void cfl_store_block(MACROBLOCKD *const xd, BLOCK_SIZE bsize, TX_SIZE tx_size) {
	CFL_CTX *const cfl = &xd->cfl;
	struct macroblockd_plane *const pd = &xd->plane[AOM_PLANE_Y];
	int row = 0;
	int col = 0;

	if (block_size_high[bsize] == 4 \|\| block_size_wide[bsize] == 4) {
	sub8x8_adjust_offset(cfl, &row, &col);
	}
	const int width = max_intra_block_width(xd, bsize, AOM_PLANE_Y, tx_size);
	const int height = max_intra_block_height(xd, bsize, AOM_PLANE_Y, tx_size);
	tx_size = get_tx_size(width, height);
	cfl_store(cfl, pd->dst.buf, pd->dst.stride, row, col, tx_size,
	is_cur_buf_hbd(xd));
	}