| /* |
| * Copyright (c) 2022, 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 <arm_neon.h> |
| |
| #include "config/aom_config.h" |
| #include "config/av1_rtcd.h" |
| #include "av1/encoder/encoder.h" |
| #include "av1/encoder/temporal_filter.h" |
| #include "aom_dsp/mathutils.h" |
| #include "aom_dsp/arm/mem_neon.h" |
| #include "aom_dsp/arm/sum_neon.h" |
| |
| // For the squared error buffer, add padding for 4 samples. |
| #define SSE_STRIDE (BW + 4) |
| |
| // When using vld1q_u16_x4 compilers may insert an alignment hint of 256 bits. |
| DECLARE_ALIGNED(32, static const uint16_t, kSlidingWindowMask[]) = { |
| 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0x0000, 0x0000, 0x0000, |
| 0x0000, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0x0000, 0x0000, |
| 0x0000, 0x0000, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0x0000, |
| 0x0000, 0x0000, 0x0000, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF |
| }; |
| |
| static INLINE void get_squared_error( |
| const uint8_t *frame1, const uint32_t stride1, const uint8_t *frame2, |
| const uint32_t stride2, const uint32_t block_width, |
| const uint32_t block_height, uint16_t *frame_sse, |
| const unsigned int dst_stride) { |
| uint16_t *dst = frame_sse; |
| |
| uint32_t i = 0; |
| do { |
| uint32_t j = 0; |
| do { |
| uint8x16_t s = vld1q_u8(frame1 + i * stride1 + j); |
| uint8x16_t r = vld1q_u8(frame2 + i * stride2 + j); |
| |
| uint8x16_t abs_diff = vabdq_u8(s, r); |
| uint16x8_t sse_lo = |
| vmull_u8(vget_low_u8(abs_diff), vget_low_u8(abs_diff)); |
| uint16x8_t sse_hi = |
| vmull_u8(vget_high_u8(abs_diff), vget_high_u8(abs_diff)); |
| |
| vst1q_u16(dst + j + 2, sse_lo); |
| vst1q_u16(dst + j + 10, sse_hi); |
| |
| j += 16; |
| } while (j < block_width); |
| |
| dst += dst_stride; |
| } while (++i < block_height); |
| } |
| |
| static INLINE uint16x8_t load_and_pad(const uint16_t *src, const uint32_t col, |
| const uint32_t block_width) { |
| uint16x8_t s = vld1q_u16(src); |
| |
| if (col == 0) { |
| const uint16_t lane2 = vgetq_lane_u16(s, 2); |
| s = vsetq_lane_u16(lane2, s, 0); |
| s = vsetq_lane_u16(lane2, s, 1); |
| } else if (col >= block_width - 4) { |
| const uint16_t lane5 = vgetq_lane_u16(s, 5); |
| s = vsetq_lane_u16(lane5, s, 6); |
| s = vsetq_lane_u16(lane5, s, 7); |
| } |
| return s; |
| } |
| |
| static void apply_temporal_filter( |
| const uint8_t *frame, const unsigned int stride, const uint32_t block_width, |
| const uint32_t block_height, const int *subblock_mses, |
| unsigned int *accumulator, uint16_t *count, const uint16_t *frame_sse, |
| const uint32_t *luma_sse_sum, const double inv_num_ref_pixels, |
| const double decay_factor, const double inv_factor, |
| const double weight_factor, const double *d_factor, int tf_wgt_calc_lvl) { |
| assert(((block_width == 16) || (block_width == 32)) && |
| ((block_height == 16) || (block_height == 32))); |
| |
| uint32_t acc_5x5_neon[BH][BW]; |
| const uint16x8x4_t vmask = vld1q_u16_x4(kSlidingWindowMask); |
| |
| // Traverse 4 columns at a time - first and last two columns need padding. |
| for (uint32_t col = 0; col < block_width; col += 4) { |
| uint16x8_t vsrc[5]; |
| const uint16_t *src = frame_sse + col; |
| |
| // Load and pad (for first and last two columns) 3 rows from the top. |
| for (int i = 2; i < 5; i++) { |
| vsrc[i] = load_and_pad(src, col, block_width); |
| src += SSE_STRIDE; |
| } |
| |
| // Pad the top 2 rows. |
| vsrc[0] = vsrc[2]; |
| vsrc[1] = vsrc[2]; |
| |
| for (unsigned int row = 0; row < block_height; row++) { |
| for (int i = 0; i < 4; i++) { |
| uint32x4_t vsum = vdupq_n_u32(0); |
| for (int j = 0; j < 5; j++) { |
| vsum = vpadalq_u16(vsum, vandq_u16(vsrc[j], vmask.val[i])); |
| } |
| acc_5x5_neon[row][col + i] = horizontal_add_u32x4(vsum); |
| } |
| |
| // Push all rows in the sliding window up one. |
| for (int i = 0; i < 4; i++) { |
| vsrc[i] = vsrc[i + 1]; |
| } |
| |
| if (row <= block_height - 4) { |
| // Load next row into the bottom of the sliding window. |
| vsrc[4] = load_and_pad(src, col, block_width); |
| src += SSE_STRIDE; |
| } else { |
| // Pad the bottom 2 rows. |
| vsrc[4] = vsrc[3]; |
| } |
| } |
| } |
| |
| // Perform filtering. |
| if (tf_wgt_calc_lvl == 0) { |
| for (unsigned int i = 0, k = 0; i < block_height; i++) { |
| for (unsigned int j = 0; j < block_width; j++, k++) { |
| const int pixel_value = frame[i * stride + j]; |
| const uint32_t diff_sse = acc_5x5_neon[i][j] + luma_sse_sum[i * BW + j]; |
| |
| const double window_error = diff_sse * inv_num_ref_pixels; |
| const int subblock_idx = |
| (i >= block_height / 2) * 2 + (j >= block_width / 2); |
| const double block_error = (double)subblock_mses[subblock_idx]; |
| const double combined_error = |
| weight_factor * window_error + block_error * inv_factor; |
| // Compute filter weight. |
| double scaled_error = |
| combined_error * d_factor[subblock_idx] * decay_factor; |
| scaled_error = AOMMIN(scaled_error, 7); |
| const int weight = (int)(exp(-scaled_error) * TF_WEIGHT_SCALE); |
| accumulator[k] += weight * pixel_value; |
| count[k] += weight; |
| } |
| } |
| } else { |
| for (unsigned int i = 0, k = 0; i < block_height; i++) { |
| for (unsigned int j = 0; j < block_width; j++, k++) { |
| const int pixel_value = frame[i * stride + j]; |
| const uint32_t diff_sse = acc_5x5_neon[i][j] + luma_sse_sum[i * BW + j]; |
| |
| const double window_error = diff_sse * inv_num_ref_pixels; |
| const int subblock_idx = |
| (i >= block_height / 2) * 2 + (j >= block_width / 2); |
| const double block_error = (double)subblock_mses[subblock_idx]; |
| const double combined_error = |
| weight_factor * window_error + block_error * inv_factor; |
| // Compute filter weight. |
| double scaled_error = |
| combined_error * d_factor[subblock_idx] * decay_factor; |
| scaled_error = AOMMIN(scaled_error, 7); |
| const float fweight = |
| approx_exp((float)-scaled_error) * TF_WEIGHT_SCALE; |
| const int weight = iroundpf(fweight); |
| accumulator[k] += weight * pixel_value; |
| count[k] += weight; |
| } |
| } |
| } |
| } |
| |
| void av1_apply_temporal_filter_neon( |
| const YV12_BUFFER_CONFIG *frame_to_filter, const MACROBLOCKD *mbd, |
| const BLOCK_SIZE block_size, const int mb_row, const int mb_col, |
| const int num_planes, const double *noise_levels, const MV *subblock_mvs, |
| const int *subblock_mses, const int q_factor, const int filter_strength, |
| int tf_wgt_calc_lvl, const uint8_t *pred, uint32_t *accum, |
| uint16_t *count) { |
| const int is_high_bitdepth = frame_to_filter->flags & YV12_FLAG_HIGHBITDEPTH; |
| assert(block_size == BLOCK_32X32 && "Only support 32x32 block with Neon!"); |
| assert(TF_WINDOW_LENGTH == 5 && "Only support window length 5 with Neon!"); |
| assert(!is_high_bitdepth && "Only support low bit-depth with Neon!"); |
| assert(num_planes >= 1 && num_planes <= MAX_MB_PLANE); |
| (void)is_high_bitdepth; |
| |
| // Block information. |
| const int mb_height = block_size_high[block_size]; |
| const int mb_width = block_size_wide[block_size]; |
| // Frame information. |
| const int frame_height = frame_to_filter->y_crop_height; |
| const int frame_width = frame_to_filter->y_crop_width; |
| const int min_frame_size = AOMMIN(frame_height, frame_width); |
| // Variables to simplify combined error calculation. |
| const double inv_factor = 1.0 / ((TF_WINDOW_BLOCK_BALANCE_WEIGHT + 1) * |
| TF_SEARCH_ERROR_NORM_WEIGHT); |
| const double weight_factor = |
| (double)TF_WINDOW_BLOCK_BALANCE_WEIGHT * inv_factor; |
| // Adjust filtering based on q. |
| // Larger q -> stronger filtering -> larger weight. |
| // Smaller q -> weaker filtering -> smaller weight. |
| double q_decay = pow((double)q_factor / TF_Q_DECAY_THRESHOLD, 2); |
| q_decay = CLIP(q_decay, 1e-5, 1); |
| if (q_factor >= TF_QINDEX_CUTOFF) { |
| // Max q_factor is 255, therefore the upper bound of q_decay is 8. |
| // We do not need a clip here. |
| q_decay = 0.5 * pow((double)q_factor / 64, 2); |
| } |
| // Smaller strength -> smaller filtering weight. |
| double s_decay = pow((double)filter_strength / TF_STRENGTH_THRESHOLD, 2); |
| s_decay = CLIP(s_decay, 1e-5, 1); |
| double d_factor[4] = { 0 }; |
| uint16_t frame_sse[SSE_STRIDE * BH] = { 0 }; |
| uint32_t luma_sse_sum[BW * BH] = { 0 }; |
| |
| for (int subblock_idx = 0; subblock_idx < 4; subblock_idx++) { |
| // Larger motion vector -> smaller filtering weight. |
| const MV mv = subblock_mvs[subblock_idx]; |
| const double distance = sqrt(pow(mv.row, 2) + pow(mv.col, 2)); |
| double distance_threshold = min_frame_size * TF_SEARCH_DISTANCE_THRESHOLD; |
| distance_threshold = AOMMAX(distance_threshold, 1); |
| d_factor[subblock_idx] = distance / distance_threshold; |
| d_factor[subblock_idx] = AOMMAX(d_factor[subblock_idx], 1); |
| } |
| |
| // Handle planes in sequence. |
| int plane_offset = 0; |
| for (int plane = 0; plane < num_planes; ++plane) { |
| const uint32_t plane_h = mb_height >> mbd->plane[plane].subsampling_y; |
| const uint32_t plane_w = mb_width >> mbd->plane[plane].subsampling_x; |
| const uint32_t frame_stride = |
| frame_to_filter->strides[plane == AOM_PLANE_Y ? 0 : 1]; |
| const int frame_offset = mb_row * plane_h * frame_stride + mb_col * plane_w; |
| |
| const uint8_t *ref = frame_to_filter->buffers[plane] + frame_offset; |
| const int ss_x_shift = |
| mbd->plane[plane].subsampling_x - mbd->plane[AOM_PLANE_Y].subsampling_x; |
| const int ss_y_shift = |
| mbd->plane[plane].subsampling_y - mbd->plane[AOM_PLANE_Y].subsampling_y; |
| const int num_ref_pixels = TF_WINDOW_LENGTH * TF_WINDOW_LENGTH + |
| ((plane) ? (1 << (ss_x_shift + ss_y_shift)) : 0); |
| const double inv_num_ref_pixels = 1.0 / num_ref_pixels; |
| // Larger noise -> larger filtering weight. |
| const double n_decay = 0.5 + log(2 * noise_levels[plane] + 5.0); |
| // Decay factors for non-local mean approach. |
| const double decay_factor = 1 / (n_decay * q_decay * s_decay); |
| |
| // Filter U-plane and V-plane using Y-plane. This is because motion |
| // search is only done on Y-plane, so the information from Y-plane |
| // will be more accurate. The luma sse sum is reused in both chroma |
| // planes. |
| if (plane == AOM_PLANE_U) { |
| for (unsigned int i = 0; i < plane_h; i++) { |
| for (unsigned int j = 0; j < plane_w; j++) { |
| for (int ii = 0; ii < (1 << ss_y_shift); ++ii) { |
| for (int jj = 0; jj < (1 << ss_x_shift); ++jj) { |
| const int yy = (i << ss_y_shift) + ii; // Y-coord on Y-plane. |
| const int xx = (j << ss_x_shift) + jj; // X-coord on Y-plane. |
| luma_sse_sum[i * BW + j] += frame_sse[yy * SSE_STRIDE + xx + 2]; |
| } |
| } |
| } |
| } |
| } |
| |
| get_squared_error(ref, frame_stride, pred + plane_offset, plane_w, plane_w, |
| plane_h, frame_sse, SSE_STRIDE); |
| |
| apply_temporal_filter(pred + plane_offset, plane_w, plane_w, plane_h, |
| subblock_mses, accum + plane_offset, |
| count + plane_offset, frame_sse, luma_sse_sum, |
| inv_num_ref_pixels, decay_factor, inv_factor, |
| weight_factor, d_factor, tf_wgt_calc_lvl); |
| |
| plane_offset += plane_h * plane_w; |
| } |
| } |
| |
| double av1_estimate_noise_from_single_plane_neon(const uint8_t *src, int height, |
| int width, int stride, |
| int edge_thresh) { |
| uint16x8_t thresh = vdupq_n_u16(edge_thresh); |
| uint32x4_t acc = vdupq_n_u32(0); |
| // Count is in theory positive as it counts the number of times we're under |
| // the threshold, but it will be counted negatively in order to make best use |
| // of the vclt instruction, which sets every bit of a lane to 1 when the |
| // condition is true. |
| int32x4_t count = vdupq_n_s32(0); |
| int final_count = 0; |
| int64_t final_acc = 0; |
| const uint8_t *src_start = src + stride + 1; |
| int h = 1; |
| |
| do { |
| int w = 1; |
| const uint8_t *src_ptr = src_start; |
| |
| while (w <= (width - 1) - 16) { |
| uint8x16_t mat[3][3]; |
| mat[0][0] = vld1q_u8(src_ptr - stride - 1); |
| mat[0][1] = vld1q_u8(src_ptr - stride); |
| mat[0][2] = vld1q_u8(src_ptr - stride + 1); |
| mat[1][0] = vld1q_u8(src_ptr - 1); |
| mat[1][1] = vld1q_u8(src_ptr); |
| mat[1][2] = vld1q_u8(src_ptr + 1); |
| mat[2][0] = vld1q_u8(src_ptr + stride - 1); |
| mat[2][1] = vld1q_u8(src_ptr + stride); |
| mat[2][2] = vld1q_u8(src_ptr + stride + 1); |
| |
| // Compute Sobel gradients. |
| uint16x8_t gxa_lo = |
| vaddl_u8(vget_low_u8(mat[0][0]), vget_low_u8(mat[2][0])); |
| uint16x8_t gxa_hi = |
| vaddl_u8(vget_high_u8(mat[0][0]), vget_high_u8(mat[2][0])); |
| uint16x8_t gxb_lo = |
| vaddl_u8(vget_low_u8(mat[0][2]), vget_low_u8(mat[2][2])); |
| uint16x8_t gxb_hi = |
| vaddl_u8(vget_high_u8(mat[0][2]), vget_high_u8(mat[2][2])); |
| gxa_lo = vaddq_u16( |
| gxa_lo, vaddl_u8(vget_low_u8(mat[1][0]), vget_low_u8(mat[1][0]))); |
| gxa_hi = vaddq_u16( |
| gxa_hi, vaddl_u8(vget_high_u8(mat[1][0]), vget_high_u8(mat[1][0]))); |
| gxb_lo = vaddq_u16( |
| gxb_lo, vaddl_u8(vget_low_u8(mat[1][2]), vget_low_u8(mat[1][2]))); |
| gxb_hi = vaddq_u16( |
| gxb_hi, vaddl_u8(vget_high_u8(mat[1][2]), vget_high_u8(mat[1][2]))); |
| |
| uint16x8_t gya_lo = |
| vaddl_u8(vget_low_u8(mat[0][0]), vget_low_u8(mat[0][2])); |
| uint16x8_t gya_hi = |
| vaddl_u8(vget_high_u8(mat[0][0]), vget_high_u8(mat[0][2])); |
| uint16x8_t gyb_lo = |
| vaddl_u8(vget_low_u8(mat[2][0]), vget_low_u8(mat[2][2])); |
| uint16x8_t gyb_hi = |
| vaddl_u8(vget_high_u8(mat[2][0]), vget_high_u8(mat[2][2])); |
| gya_lo = vaddq_u16( |
| gya_lo, vaddl_u8(vget_low_u8(mat[0][1]), vget_low_u8(mat[0][1]))); |
| gya_hi = vaddq_u16( |
| gya_hi, vaddl_u8(vget_high_u8(mat[0][1]), vget_high_u8(mat[0][1]))); |
| gyb_lo = vaddq_u16( |
| gyb_lo, vaddl_u8(vget_low_u8(mat[2][1]), vget_low_u8(mat[2][1]))); |
| gyb_hi = vaddq_u16( |
| gyb_hi, vaddl_u8(vget_high_u8(mat[2][1]), vget_high_u8(mat[2][1]))); |
| |
| uint16x8_t ga_lo = vabaq_u16(vabdq_u16(gxa_lo, gxb_lo), gya_lo, gyb_lo); |
| uint16x8_t ga_hi = vabaq_u16(vabdq_u16(gxa_hi, gxb_hi), gya_hi, gyb_hi); |
| |
| // Check which vector elements are under the threshold. The Laplacian is |
| // then unconditionally computed and we accumulate zeros if we're not |
| // under the threshold. This is much faster than using an if statement. |
| uint16x8_t thresh_u16_lo = vcltq_u16(ga_lo, thresh); |
| uint16x8_t thresh_u16_hi = vcltq_u16(ga_hi, thresh); |
| |
| uint16x8_t center_lo = vshll_n_u8(vget_low_u8(mat[1][1]), 2); |
| uint16x8_t center_hi = vshll_n_u8(vget_high_u8(mat[1][1]), 2); |
| |
| uint16x8_t adj0_lo = |
| vaddl_u8(vget_low_u8(mat[0][1]), vget_low_u8(mat[2][1])); |
| uint16x8_t adj0_hi = |
| vaddl_u8(vget_high_u8(mat[0][1]), vget_high_u8(mat[2][1])); |
| uint16x8_t adj1_lo = |
| vaddl_u8(vget_low_u8(mat[1][0]), vget_low_u8(mat[1][2])); |
| uint16x8_t adj1_hi = |
| vaddl_u8(vget_high_u8(mat[1][0]), vget_high_u8(mat[1][2])); |
| uint16x8_t adj_lo = vaddq_u16(adj0_lo, adj1_lo); |
| adj_lo = vaddq_u16(adj_lo, adj_lo); |
| uint16x8_t adj_hi = vaddq_u16(adj0_hi, adj1_hi); |
| adj_hi = vaddq_u16(adj_hi, adj_hi); |
| |
| uint16x8_t diag0_lo = |
| vaddl_u8(vget_low_u8(mat[0][0]), vget_low_u8(mat[0][2])); |
| uint16x8_t diag0_hi = |
| vaddl_u8(vget_high_u8(mat[0][0]), vget_high_u8(mat[0][2])); |
| uint16x8_t diag1_lo = |
| vaddl_u8(vget_low_u8(mat[2][0]), vget_low_u8(mat[2][2])); |
| uint16x8_t diag1_hi = |
| vaddl_u8(vget_high_u8(mat[2][0]), vget_high_u8(mat[2][2])); |
| uint16x8_t diag_lo = vaddq_u16(diag0_lo, diag1_lo); |
| uint16x8_t diag_hi = vaddq_u16(diag0_hi, diag1_hi); |
| |
| uint16x8_t v_lo = vaddq_u16(center_lo, diag_lo); |
| v_lo = vabdq_u16(v_lo, adj_lo); |
| uint16x8_t v_hi = vaddq_u16(center_hi, diag_hi); |
| v_hi = vabdq_u16(v_hi, adj_hi); |
| |
| acc = vpadalq_u16(acc, vandq_u16(v_lo, thresh_u16_lo)); |
| acc = vpadalq_u16(acc, vandq_u16(v_hi, thresh_u16_hi)); |
| |
| // Add -1 for each lane where the gradient is under the threshold. |
| count = vpadalq_s16(count, vreinterpretq_s16_u16(thresh_u16_lo)); |
| count = vpadalq_s16(count, vreinterpretq_s16_u16(thresh_u16_hi)); |
| |
| w += 16; |
| src_ptr += 16; |
| } |
| |
| if (w <= (width - 1) - 8) { |
| uint8x8_t mat[3][3]; |
| mat[0][0] = vld1_u8(src_ptr - stride - 1); |
| mat[0][1] = vld1_u8(src_ptr - stride); |
| mat[0][2] = vld1_u8(src_ptr - stride + 1); |
| mat[1][0] = vld1_u8(src_ptr - 1); |
| mat[1][1] = vld1_u8(src_ptr); |
| mat[1][2] = vld1_u8(src_ptr + 1); |
| mat[2][0] = vld1_u8(src_ptr + stride - 1); |
| mat[2][1] = vld1_u8(src_ptr + stride); |
| mat[2][2] = vld1_u8(src_ptr + stride + 1); |
| |
| // Compute Sobel gradients. |
| uint16x8_t gxa = vaddl_u8(mat[0][0], mat[2][0]); |
| uint16x8_t gxb = vaddl_u8(mat[0][2], mat[2][2]); |
| gxa = vaddq_u16(gxa, vaddl_u8(mat[1][0], mat[1][0])); |
| gxb = vaddq_u16(gxb, vaddl_u8(mat[1][2], mat[1][2])); |
| |
| uint16x8_t gya = vaddl_u8(mat[0][0], mat[0][2]); |
| uint16x8_t gyb = vaddl_u8(mat[2][0], mat[2][2]); |
| gya = vaddq_u16(gya, vaddl_u8(mat[0][1], mat[0][1])); |
| gyb = vaddq_u16(gyb, vaddl_u8(mat[2][1], mat[2][1])); |
| |
| uint16x8_t ga = vabaq_u16(vabdq_u16(gxa, gxb), gya, gyb); |
| |
| // Check which vector elements are under the threshold. The Laplacian is |
| // then unconditionally computed and we accumulate zeros if we're not |
| // under the threshold. This is much faster than using an if statement. |
| uint16x8_t thresh_u16 = vcltq_u16(ga, thresh); |
| |
| uint16x8_t center = vshll_n_u8(mat[1][1], 2); |
| |
| uint16x8_t adj0 = vaddl_u8(mat[0][1], mat[2][1]); |
| uint16x8_t adj1 = vaddl_u8(mat[1][0], mat[1][2]); |
| uint16x8_t adj = vaddq_u16(adj0, adj1); |
| adj = vaddq_u16(adj, adj); |
| |
| uint16x8_t diag0 = vaddl_u8(mat[0][0], mat[0][2]); |
| uint16x8_t diag1 = vaddl_u8(mat[2][0], mat[2][2]); |
| uint16x8_t diag = vaddq_u16(diag0, diag1); |
| |
| uint16x8_t v = vaddq_u16(center, diag); |
| v = vabdq_u16(v, adj); |
| |
| acc = vpadalq_u16(acc, vandq_u16(v, thresh_u16)); |
| // Add -1 for each lane where the gradient is under the threshold. |
| count = vpadalq_s16(count, vreinterpretq_s16_u16(thresh_u16)); |
| |
| w += 8; |
| src_ptr += 8; |
| } |
| |
| if (w <= (width - 1) - 4) { |
| uint16x8_t mask = vcombine_u16(vdup_n_u16(65535), vdup_n_u16(0)); |
| uint8x8_t mat[3][3]; |
| mat[0][0] = load_unaligned_u8_4x1(src_ptr - stride - 1); |
| mat[0][1] = load_unaligned_u8_4x1(src_ptr - stride); |
| mat[0][2] = load_unaligned_u8_4x1(src_ptr - stride + 1); |
| mat[1][0] = load_unaligned_u8_4x1(src_ptr - 1); |
| mat[1][1] = load_unaligned_u8_4x1(src_ptr); |
| mat[1][2] = load_unaligned_u8_4x1(src_ptr + 1); |
| mat[2][0] = load_unaligned_u8_4x1(src_ptr + stride - 1); |
| mat[2][1] = load_unaligned_u8_4x1(src_ptr + stride); |
| mat[2][2] = load_unaligned_u8_4x1(src_ptr + stride + 1); |
| |
| // Compute Sobel gradients. |
| uint16x8_t gxa = vaddl_u8(mat[0][0], mat[2][0]); |
| uint16x8_t gxb = vaddl_u8(mat[0][2], mat[2][2]); |
| gxa = vaddq_u16(gxa, vaddl_u8(mat[1][0], mat[1][0])); |
| gxb = vaddq_u16(gxb, vaddl_u8(mat[1][2], mat[1][2])); |
| |
| uint16x8_t gya = vaddl_u8(mat[0][0], mat[0][2]); |
| uint16x8_t gyb = vaddl_u8(mat[2][0], mat[2][2]); |
| gya = vaddq_u16(gya, vaddl_u8(mat[0][1], mat[0][1])); |
| gyb = vaddq_u16(gyb, vaddl_u8(mat[2][1], mat[2][1])); |
| |
| uint16x8_t ga = vabaq_u16(vabdq_u16(gxa, gxb), gya, gyb); |
| |
| // Check which vector elements are under the threshold. The Laplacian is |
| // then unconditionally computed and we accumulate zeros if we're not |
| // under the threshold. This is much faster than using an if statement. |
| uint16x8_t thresh_u16 = vandq_u16(vcltq_u16(ga, thresh), mask); |
| |
| uint16x8_t center = vshll_n_u8(mat[1][1], 2); |
| |
| uint16x8_t adj0 = vaddl_u8(mat[0][1], mat[2][1]); |
| uint16x8_t adj1 = vaddl_u8(mat[1][0], mat[1][2]); |
| uint16x8_t adj = vaddq_u16(adj0, adj1); |
| adj = vaddq_u16(adj, adj); |
| |
| uint16x8_t diag0 = vaddl_u8(mat[0][0], mat[0][2]); |
| uint16x8_t diag1 = vaddl_u8(mat[2][0], mat[2][2]); |
| uint16x8_t diag = vaddq_u16(diag0, diag1); |
| |
| uint16x8_t v = vaddq_u16(center, diag); |
| v = vabdq_u16(v, adj); |
| |
| acc = vpadalq_u16(acc, vandq_u16(v, thresh_u16)); |
| // Add -1 for each lane where the gradient is under the threshold. |
| count = vpadalq_s16(count, vreinterpretq_s16_u16(thresh_u16)); |
| |
| w += 4; |
| src_ptr += 4; |
| } |
| |
| while (w < width - 1) { |
| int mat[3][3]; |
| mat[0][0] = *(src_ptr - stride - 1); |
| mat[0][1] = *(src_ptr - stride); |
| mat[0][2] = *(src_ptr - stride + 1); |
| mat[1][0] = *(src_ptr - 1); |
| mat[1][1] = *(src_ptr); |
| mat[1][2] = *(src_ptr + 1); |
| mat[2][0] = *(src_ptr + stride - 1); |
| mat[2][1] = *(src_ptr + stride); |
| mat[2][2] = *(src_ptr + stride + 1); |
| |
| // Compute Sobel gradients. |
| const int gx = (mat[0][0] - mat[0][2]) + (mat[2][0] - mat[2][2]) + |
| 2 * (mat[1][0] - mat[1][2]); |
| const int gy = (mat[0][0] - mat[2][0]) + (mat[0][2] - mat[2][2]) + |
| 2 * (mat[0][1] - mat[2][1]); |
| const int ga = abs(gx) + abs(gy); |
| |
| // Accumulate Laplacian. |
| const int is_under = ga < edge_thresh; |
| const int v = 4 * mat[1][1] - |
| 2 * (mat[0][1] + mat[2][1] + mat[1][0] + mat[1][2]) + |
| (mat[0][0] + mat[0][2] + mat[2][0] + mat[2][2]); |
| final_acc += abs(v) * is_under; |
| final_count += is_under; |
| |
| src_ptr++; |
| w++; |
| } |
| src_start += stride; |
| } while (++h < height - 1); |
| |
| // We counted negatively, so subtract to get the final value. |
| final_count -= horizontal_add_s32x4(count); |
| final_acc += horizontal_long_add_u32x4(acc); |
| return (final_count < 16) |
| ? -1.0 |
| : (double)final_acc / (6 * final_count) * SQRT_PI_BY_2; |
| } |
