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av1_temporal_denoiser_neon.c (14976B)


      1 /*
      2 * Copyright (c) 2020, Alliance for Open Media. All rights reserved.
      3 *
      4 * This source code is subject to the terms of the BSD 2 Clause License and
      5 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
      6 * was not distributed with this source code in the LICENSE file, you can
      7 * obtain it at www.aomedia.org/license/software. If the Alliance for Open
      8 * Media Patent License 1.0 was not distributed with this source code in the
      9 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
     10 */
     11 
     12 #include <arm_neon.h>
     13 #include <assert.h>
     14 
     15 #include "aom/aom_integer.h"
     16 #include "aom_dsp/arm/mem_neon.h"
     17 #include "aom_ports/mem.h"
     18 #include "config/aom_config.h"
     19 #include "config/av1_rtcd.h"
     20 
     21 #include "av1/common/reconinter.h"
     22 #include "av1/encoder/context_tree.h"
     23 #include "av1/encoder/av1_temporal_denoiser.h"
     24 
     25 // Compute the sum of all pixel differences of this MB.
     26 static inline int horizontal_add_s8x16(const int8x16_t v_sum_diff_total) {
     27 #if AOM_ARCH_AARCH64
     28  return vaddlvq_s8(v_sum_diff_total);
     29 #else
     30  const int16x8_t fe_dc_ba_98_76_54_32_10 = vpaddlq_s8(v_sum_diff_total);
     31  const int32x4_t fedc_ba98_7654_3210 = vpaddlq_s16(fe_dc_ba_98_76_54_32_10);
     32  const int64x2_t fedcba98_76543210 = vpaddlq_s32(fedc_ba98_7654_3210);
     33  const int64x1_t x = vqadd_s64(vget_high_s64(fedcba98_76543210),
     34                                vget_low_s64(fedcba98_76543210));
     35  const int sum_diff = vget_lane_s32(vreinterpret_s32_s64(x), 0);
     36  return sum_diff;
     37 #endif
     38 }
     39 
     40 // Denoise a 16x1 vector.
     41 static inline int8x16_t denoiser_16x1_neon(
     42    const uint8_t *sig, const uint8_t *mc_running_avg_y, uint8_t *running_avg_y,
     43    const uint8x16_t v_level1_threshold, const uint8x16_t v_level2_threshold,
     44    const uint8x16_t v_level3_threshold, const uint8x16_t v_level1_adjustment,
     45    const uint8x16_t v_delta_level_1_and_2,
     46    const uint8x16_t v_delta_level_2_and_3, int8x16_t v_sum_diff_total) {
     47  const uint8x16_t v_sig = vld1q_u8(sig);
     48  const uint8x16_t v_mc_running_avg_y = vld1q_u8(mc_running_avg_y);
     49 
     50  /* Calculate absolute difference and sign masks. */
     51  const uint8x16_t v_abs_diff = vabdq_u8(v_sig, v_mc_running_avg_y);
     52  const uint8x16_t v_diff_pos_mask = vcltq_u8(v_sig, v_mc_running_avg_y);
     53  const uint8x16_t v_diff_neg_mask = vcgtq_u8(v_sig, v_mc_running_avg_y);
     54 
     55  /* Figure out which level that put us in. */
     56  const uint8x16_t v_level1_mask = vcleq_u8(v_level1_threshold, v_abs_diff);
     57  const uint8x16_t v_level2_mask = vcleq_u8(v_level2_threshold, v_abs_diff);
     58  const uint8x16_t v_level3_mask = vcleq_u8(v_level3_threshold, v_abs_diff);
     59 
     60  /* Calculate absolute adjustments for level 1, 2 and 3. */
     61  const uint8x16_t v_level2_adjustment =
     62      vandq_u8(v_level2_mask, v_delta_level_1_and_2);
     63  const uint8x16_t v_level3_adjustment =
     64      vandq_u8(v_level3_mask, v_delta_level_2_and_3);
     65  const uint8x16_t v_level1and2_adjustment =
     66      vaddq_u8(v_level1_adjustment, v_level2_adjustment);
     67  const uint8x16_t v_level1and2and3_adjustment =
     68      vaddq_u8(v_level1and2_adjustment, v_level3_adjustment);
     69 
     70  /* Figure adjustment absolute value by selecting between the absolute
     71   * difference if in level0 or the value for level 1, 2 and 3.
     72   */
     73  const uint8x16_t v_abs_adjustment =
     74      vbslq_u8(v_level1_mask, v_level1and2and3_adjustment, v_abs_diff);
     75 
     76  /* Calculate positive and negative adjustments. Apply them to the signal
     77   * and accumulate them. Adjustments are less than eight and the maximum
     78   * sum of them (7 * 16) can fit in a signed char.
     79   */
     80  const uint8x16_t v_pos_adjustment =
     81      vandq_u8(v_diff_pos_mask, v_abs_adjustment);
     82  const uint8x16_t v_neg_adjustment =
     83      vandq_u8(v_diff_neg_mask, v_abs_adjustment);
     84 
     85  uint8x16_t v_running_avg_y = vqaddq_u8(v_sig, v_pos_adjustment);
     86  v_running_avg_y = vqsubq_u8(v_running_avg_y, v_neg_adjustment);
     87 
     88  /* Store results. */
     89  vst1q_u8(running_avg_y, v_running_avg_y);
     90 
     91  /* Sum all the accumulators to have the sum of all pixel differences
     92   * for this macroblock.
     93   */
     94  {
     95    const int8x16_t v_sum_diff =
     96        vqsubq_s8(vreinterpretq_s8_u8(v_pos_adjustment),
     97                  vreinterpretq_s8_u8(v_neg_adjustment));
     98    v_sum_diff_total = vaddq_s8(v_sum_diff_total, v_sum_diff);
     99  }
    100  return v_sum_diff_total;
    101 }
    102 
    103 static inline int8x16_t denoiser_adjust_16x1_neon(
    104    const uint8_t *sig, const uint8_t *mc_running_avg_y, uint8_t *running_avg_y,
    105    const uint8x16_t k_delta, int8x16_t v_sum_diff_total) {
    106  uint8x16_t v_running_avg_y = vld1q_u8(running_avg_y);
    107  const uint8x16_t v_sig = vld1q_u8(sig);
    108  const uint8x16_t v_mc_running_avg_y = vld1q_u8(mc_running_avg_y);
    109 
    110  /* Calculate absolute difference and sign masks. */
    111  const uint8x16_t v_abs_diff = vabdq_u8(v_sig, v_mc_running_avg_y);
    112  const uint8x16_t v_diff_pos_mask = vcltq_u8(v_sig, v_mc_running_avg_y);
    113  const uint8x16_t v_diff_neg_mask = vcgtq_u8(v_sig, v_mc_running_avg_y);
    114  // Clamp absolute difference to delta to get the adjustment.
    115  const uint8x16_t v_abs_adjustment = vminq_u8(v_abs_diff, (k_delta));
    116 
    117  const uint8x16_t v_pos_adjustment =
    118      vandq_u8(v_diff_pos_mask, v_abs_adjustment);
    119  const uint8x16_t v_neg_adjustment =
    120      vandq_u8(v_diff_neg_mask, v_abs_adjustment);
    121 
    122  v_running_avg_y = vqsubq_u8(v_running_avg_y, v_pos_adjustment);
    123  v_running_avg_y = vqaddq_u8(v_running_avg_y, v_neg_adjustment);
    124 
    125  /* Store results. */
    126  vst1q_u8(running_avg_y, v_running_avg_y);
    127 
    128  {
    129    const int8x16_t v_sum_diff =
    130        vqsubq_s8(vreinterpretq_s8_u8(v_neg_adjustment),
    131                  vreinterpretq_s8_u8(v_pos_adjustment));
    132    v_sum_diff_total = vaddq_s8(v_sum_diff_total, v_sum_diff);
    133  }
    134  return v_sum_diff_total;
    135 }
    136 
    137 // Denoise 8x8 and 8x16 blocks.
    138 static int av1_denoiser_8xN_neon(const uint8_t *sig, int sig_stride,
    139                                 const uint8_t *mc_running_avg_y,
    140                                 int mc_avg_y_stride, uint8_t *running_avg_y,
    141                                 int avg_y_stride, int increase_denoising,
    142                                 BLOCK_SIZE bs, int motion_magnitude,
    143                                 int width) {
    144  int sum_diff_thresh, r, sum_diff = 0;
    145  const int shift_inc =
    146      (increase_denoising && motion_magnitude <= MOTION_MAGNITUDE_THRESHOLD)
    147          ? 1
    148          : 0;
    149  uint8_t sig_buffer[8][16], mc_running_buffer[8][16], running_buffer[8][16];
    150 
    151  const uint8x16_t v_level1_adjustment = vmovq_n_u8(
    152      (motion_magnitude <= MOTION_MAGNITUDE_THRESHOLD) ? 4 + shift_inc : 3);
    153  const uint8x16_t v_delta_level_1_and_2 = vdupq_n_u8(1);
    154  const uint8x16_t v_delta_level_2_and_3 = vdupq_n_u8(2);
    155  const uint8x16_t v_level1_threshold = vdupq_n_u8(4 + shift_inc);
    156  const uint8x16_t v_level2_threshold = vdupq_n_u8(8);
    157  const uint8x16_t v_level3_threshold = vdupq_n_u8(16);
    158 
    159  const int b_height = block_size_high[bs] >> 1;
    160 
    161  int8x16_t v_sum_diff_total = vdupq_n_s8(0);
    162 
    163  for (r = 0; r < b_height; ++r) {
    164    memcpy(sig_buffer[r], sig, width);
    165    memcpy(sig_buffer[r] + width, sig + sig_stride, width);
    166    memcpy(mc_running_buffer[r], mc_running_avg_y, width);
    167    memcpy(mc_running_buffer[r] + width, mc_running_avg_y + mc_avg_y_stride,
    168           width);
    169    memcpy(running_buffer[r], running_avg_y, width);
    170    memcpy(running_buffer[r] + width, running_avg_y + avg_y_stride, width);
    171    v_sum_diff_total = denoiser_16x1_neon(
    172        sig_buffer[r], mc_running_buffer[r], running_buffer[r],
    173        v_level1_threshold, v_level2_threshold, v_level3_threshold,
    174        v_level1_adjustment, v_delta_level_1_and_2, v_delta_level_2_and_3,
    175        v_sum_diff_total);
    176    {
    177      const uint8x16_t v_running_buffer = vld1q_u8(running_buffer[r]);
    178      const uint8x8_t v_running_buffer_high = vget_high_u8(v_running_buffer);
    179      const uint8x8_t v_running_buffer_low = vget_low_u8(v_running_buffer);
    180      vst1_u8(running_avg_y, v_running_buffer_low);
    181      vst1_u8(running_avg_y + avg_y_stride, v_running_buffer_high);
    182    }
    183    // Update pointers for next iteration.
    184    sig += (sig_stride << 1);
    185    mc_running_avg_y += (mc_avg_y_stride << 1);
    186    running_avg_y += (avg_y_stride << 1);
    187  }
    188 
    189  {
    190    sum_diff = horizontal_add_s8x16(v_sum_diff_total);
    191    sum_diff_thresh = total_adj_strong_thresh(bs, increase_denoising);
    192    if (abs(sum_diff) > sum_diff_thresh) {
    193      // Before returning to copy the block (i.e., apply no denoising),
    194      // check if we can still apply some (weaker) temporal filtering to
    195      // this block, that would otherwise not be denoised at all. Simplest
    196      // is to apply an additional adjustment to running_avg_y to bring it
    197      // closer to sig. The adjustment is capped by a maximum delta, and
    198      // chosen such that in most cases the resulting sum_diff will be
    199      // within the acceptable range given by sum_diff_thresh.
    200 
    201      // The delta is set by the excess of absolute pixel diff over the
    202      // threshold.
    203      const int delta =
    204          ((abs(sum_diff) - sum_diff_thresh) >> num_pels_log2_lookup[bs]) + 1;
    205      // Only apply the adjustment for max delta up to 3.
    206      if (delta < 4) {
    207        const uint8x16_t k_delta = vmovq_n_u8(delta);
    208        running_avg_y -= avg_y_stride * (b_height << 1);
    209        for (r = 0; r < b_height; ++r) {
    210          v_sum_diff_total = denoiser_adjust_16x1_neon(
    211              sig_buffer[r], mc_running_buffer[r], running_buffer[r], k_delta,
    212              v_sum_diff_total);
    213          {
    214            const uint8x16_t v_running_buffer = vld1q_u8(running_buffer[r]);
    215            const uint8x8_t v_running_buffer_high =
    216                vget_high_u8(v_running_buffer);
    217            const uint8x8_t v_running_buffer_low =
    218                vget_low_u8(v_running_buffer);
    219            vst1_u8(running_avg_y, v_running_buffer_low);
    220            vst1_u8(running_avg_y + avg_y_stride, v_running_buffer_high);
    221          }
    222          // Update pointers for next iteration.
    223          running_avg_y += (avg_y_stride << 1);
    224        }
    225        sum_diff = horizontal_add_s8x16(v_sum_diff_total);
    226        if (abs(sum_diff) > sum_diff_thresh) {
    227          return COPY_BLOCK;
    228        }
    229      } else {
    230        return COPY_BLOCK;
    231      }
    232    }
    233  }
    234 
    235  return FILTER_BLOCK;
    236 }
    237 
    238 // Denoise 16x16, to 128x128 blocks.
    239 static int av1_denoiser_NxM_neon(const uint8_t *sig, int sig_stride,
    240                                 const uint8_t *mc_running_avg_y,
    241                                 int mc_avg_y_stride, uint8_t *running_avg_y,
    242                                 int avg_y_stride, int increase_denoising,
    243                                 BLOCK_SIZE bs, int motion_magnitude) {
    244  const int shift_inc =
    245      (increase_denoising && motion_magnitude <= MOTION_MAGNITUDE_THRESHOLD)
    246          ? 1
    247          : 0;
    248  const uint8x16_t v_level1_adjustment = vmovq_n_u8(
    249      (motion_magnitude <= MOTION_MAGNITUDE_THRESHOLD) ? 4 + shift_inc : 3);
    250  const uint8x16_t v_delta_level_1_and_2 = vdupq_n_u8(1);
    251  const uint8x16_t v_delta_level_2_and_3 = vdupq_n_u8(2);
    252  const uint8x16_t v_level1_threshold = vmovq_n_u8(4 + shift_inc);
    253  const uint8x16_t v_level2_threshold = vdupq_n_u8(8);
    254  const uint8x16_t v_level3_threshold = vdupq_n_u8(16);
    255 
    256  const int b_width = block_size_wide[bs];
    257  const int b_height = block_size_high[bs];
    258  const int b_width_shift4 = b_width >> 4;
    259 
    260  int8x16_t v_sum_diff_total[8][8];
    261  int r, c, sum_diff = 0;
    262 
    263  for (r = 0; r < 8; ++r) {
    264    for (c = 0; c < b_width_shift4; ++c) {
    265      v_sum_diff_total[c][r] = vdupq_n_s8(0);
    266    }
    267  }
    268 
    269  for (r = 0; r < b_height; ++r) {
    270    for (c = 0; c < b_width_shift4; ++c) {
    271      v_sum_diff_total[c][r >> 4] = denoiser_16x1_neon(
    272          sig, mc_running_avg_y, running_avg_y, v_level1_threshold,
    273          v_level2_threshold, v_level3_threshold, v_level1_adjustment,
    274          v_delta_level_1_and_2, v_delta_level_2_and_3,
    275          v_sum_diff_total[c][r >> 4]);
    276 
    277      // Update pointers for next iteration.
    278      sig += 16;
    279      mc_running_avg_y += 16;
    280      running_avg_y += 16;
    281    }
    282 
    283    if ((r & 0xf) == 0xf || (bs == BLOCK_16X8 && r == 7)) {
    284      for (c = 0; c < b_width_shift4; ++c) {
    285        sum_diff += horizontal_add_s8x16(v_sum_diff_total[c][r >> 4]);
    286      }
    287    }
    288 
    289    // Update pointers for next iteration.
    290    sig = sig - b_width + sig_stride;
    291    mc_running_avg_y = mc_running_avg_y - b_width + mc_avg_y_stride;
    292    running_avg_y = running_avg_y - b_width + avg_y_stride;
    293  }
    294 
    295  {
    296    const int sum_diff_thresh = total_adj_strong_thresh(bs, increase_denoising);
    297    if (abs(sum_diff) > sum_diff_thresh) {
    298      const int delta =
    299          ((abs(sum_diff) - sum_diff_thresh) >> num_pels_log2_lookup[bs]) + 1;
    300      // Only apply the adjustment for max delta up to 3.
    301      if (delta < 4) {
    302        const uint8x16_t k_delta = vdupq_n_u8(delta);
    303        sig -= sig_stride * b_height;
    304        mc_running_avg_y -= mc_avg_y_stride * b_height;
    305        running_avg_y -= avg_y_stride * b_height;
    306        sum_diff = 0;
    307 
    308        for (r = 0; r < b_height; ++r) {
    309          for (c = 0; c < b_width_shift4; ++c) {
    310            v_sum_diff_total[c][r >> 4] =
    311                denoiser_adjust_16x1_neon(sig, mc_running_avg_y, running_avg_y,
    312                                          k_delta, v_sum_diff_total[c][r >> 4]);
    313 
    314            // Update pointers for next iteration.
    315            sig += 16;
    316            mc_running_avg_y += 16;
    317            running_avg_y += 16;
    318          }
    319          if ((r & 0xf) == 0xf || (bs == BLOCK_16X8 && r == 7)) {
    320            for (c = 0; c < b_width_shift4; ++c) {
    321              sum_diff += horizontal_add_s8x16(v_sum_diff_total[c][r >> 4]);
    322            }
    323          }
    324 
    325          sig = sig - b_width + sig_stride;
    326          mc_running_avg_y = mc_running_avg_y - b_width + mc_avg_y_stride;
    327          running_avg_y = running_avg_y - b_width + avg_y_stride;
    328        }
    329 
    330        if (abs(sum_diff) > sum_diff_thresh) {
    331          return COPY_BLOCK;
    332        }
    333      } else {
    334        return COPY_BLOCK;
    335      }
    336    }
    337  }
    338  return FILTER_BLOCK;
    339 }
    340 
    341 int av1_denoiser_filter_neon(const uint8_t *sig, int sig_stride,
    342                             const uint8_t *mc_avg, int mc_avg_stride,
    343                             uint8_t *avg, int avg_stride,
    344                             int increase_denoising, BLOCK_SIZE bs,
    345                             int motion_magnitude) {
    346  // Rank by frequency of the block type to have an early termination.
    347  if (bs == BLOCK_16X16 || bs == BLOCK_32X32 || bs == BLOCK_64X64 ||
    348      bs == BLOCK_128X128 || bs == BLOCK_128X64 || bs == BLOCK_64X128 ||
    349      bs == BLOCK_16X32 || bs == BLOCK_16X8 || bs == BLOCK_32X16 ||
    350      bs == BLOCK_32X64 || bs == BLOCK_64X32) {
    351    return av1_denoiser_NxM_neon(sig, sig_stride, mc_avg, mc_avg_stride, avg,
    352                                 avg_stride, increase_denoising, bs,
    353                                 motion_magnitude);
    354  } else if (bs == BLOCK_8X8 || bs == BLOCK_8X16) {
    355    return av1_denoiser_8xN_neon(sig, sig_stride, mc_avg, mc_avg_stride, avg,
    356                                 avg_stride, increase_denoising, bs,
    357                                 motion_magnitude, 8);
    358  }
    359  return COPY_BLOCK;
    360 }