libvpx: Pull from upstream

source/libvpx/vp8/encoder/arm/neon/denoising_neon.c

Index: source/libvpx/vp8/encoder/arm/neon/denoising_neon.c
===================================================================
--- source/libvpx/vp8/encoder/arm/neon/denoising_neon.c	(revision 281795)
+++ source/libvpx/vp8/encoder/arm/neon/denoising_neon.c	(working copy)
@@ -240,3 +240,239 @@
 
     return FILTER_BLOCK;
 }
+
+int vp8_denoiser_filter_uv_neon(unsigned char *mc_running_avg,
+                             int mc_running_avg_stride,
+                             unsigned char *running_avg,
+                             int running_avg_stride,
+                             unsigned char *sig, int sig_stride,
+                             unsigned int motion_magnitude,
+                             int increase_denoising) {
+    /* If motion_magnitude is small, making the denoiser more aggressive by
+     * increasing the adjustment for each level, level1 adjustment is
+     * increased, the deltas stay the same.
+     */
+    int shift_inc  = (increase_denoising &&
+        motion_magnitude <= MOTION_MAGNITUDE_THRESHOLD_UV) ? 1 : 0;
+    const uint8x16_t v_level1_adjustment = vmovq_n_u8(
+        (motion_magnitude <= MOTION_MAGNITUDE_THRESHOLD_UV) ? 4 + shift_inc : 3);
+
+    const uint8x16_t v_delta_level_1_and_2 = vdupq_n_u8(1);
+    const uint8x16_t v_delta_level_2_and_3 = vdupq_n_u8(2);
+    const uint8x16_t v_level1_threshold = vmovq_n_u8(4 + shift_inc);
+    const uint8x16_t v_level2_threshold = vdupq_n_u8(8);
+    const uint8x16_t v_level3_threshold = vdupq_n_u8(16);
+    int64x2_t v_sum_diff_total = vdupq_n_s64(0);
+    int r;
+
+    {
+      uint16x4_t v_sum_block = vdup_n_u16(0);
+
+      // Avoid denoising color signal if its close to average level.
+      for (r = 0; r < 8; ++r) {
+        const uint8x8_t v_sig = vld1_u8(sig);
+        const uint16x4_t _76_54_32_10 = vpaddl_u8(v_sig);
+        v_sum_block = vqadd_u16(v_sum_block, _76_54_32_10);
+        sig += sig_stride;
+      }
+      sig -= sig_stride * 8;
+      {
+        const uint32x2_t _7654_3210 = vpaddl_u16(v_sum_block);
+        const uint64x1_t _76543210 = vpaddl_u32(_7654_3210);
+        const unsigned int sum_block =
+            vget_lane_u32(vreinterpret_u32_u64(_76543210), 0);
+        if (abs(sum_block - (128 * 8 * 8)) < SUM_DIFF_FROM_AVG_THRESH_UV) {
+          return COPY_BLOCK;
+        }
+      }
+    }
+
+    /* Go over lines. */
+    for (r = 0; r < 4; ++r) {
+        /* Load inputs. */
+        const uint8x8_t v_sig_lo = vld1_u8(sig);
+        const uint8x8_t v_sig_hi = vld1_u8(&sig[sig_stride]);
+        const uint8x16_t v_sig = vcombine_u8(v_sig_lo, v_sig_hi);
+        const uint8x8_t v_mc_running_avg_lo = vld1_u8(mc_running_avg);
+        const uint8x8_t v_mc_running_avg_hi =
+            vld1_u8(&mc_running_avg[mc_running_avg_stride]);
+        const uint8x16_t v_mc_running_avg =
+            vcombine_u8(v_mc_running_avg_lo, v_mc_running_avg_hi);
+        /* Calculate absolute difference and sign masks. */
+        const uint8x16_t v_abs_diff      = vabdq_u8(v_sig, v_mc_running_avg);
+        const uint8x16_t v_diff_pos_mask = vcltq_u8(v_sig, v_mc_running_avg);
+        const uint8x16_t v_diff_neg_mask = vcgtq_u8(v_sig, v_mc_running_avg);
+
+        /* Figure out which level that put us in. */
+        const uint8x16_t v_level1_mask = vcleq_u8(v_level1_threshold,
+                                                  v_abs_diff);
+        const uint8x16_t v_level2_mask = vcleq_u8(v_level2_threshold,
+                                                  v_abs_diff);
+        const uint8x16_t v_level3_mask = vcleq_u8(v_level3_threshold,
+                                                  v_abs_diff);
+
+        /* Calculate absolute adjustments for level 1, 2 and 3. */
+        const uint8x16_t v_level2_adjustment = vandq_u8(v_level2_mask,
+                                                        v_delta_level_1_and_2);
+        const uint8x16_t v_level3_adjustment = vandq_u8(v_level3_mask,
+                                                        v_delta_level_2_and_3);
+        const uint8x16_t v_level1and2_adjustment = vaddq_u8(v_level1_adjustment,
+            v_level2_adjustment);
+        const uint8x16_t v_level1and2and3_adjustment = vaddq_u8(
+            v_level1and2_adjustment, v_level3_adjustment);
+
+        /* Figure adjustment absolute value by selecting between the absolute
+         * difference if in level0 or the value for level 1, 2 and 3.
+         */
+        const uint8x16_t v_abs_adjustment = vbslq_u8(v_level1_mask,
+            v_level1and2and3_adjustment, v_abs_diff);
+
+        /* Calculate positive and negative adjustments. Apply them to the signal
+         * and accumulate them. Adjustments are less than eight and the maximum
+         * sum of them (7 * 16) can fit in a signed char.
+         */
+        const uint8x16_t v_pos_adjustment = vandq_u8(v_diff_pos_mask,
+                                                     v_abs_adjustment);
+        const uint8x16_t v_neg_adjustment = vandq_u8(v_diff_neg_mask,
+                                                     v_abs_adjustment);
+
+        uint8x16_t v_running_avg = vqaddq_u8(v_sig, v_pos_adjustment);
+        v_running_avg = vqsubq_u8(v_running_avg, v_neg_adjustment);
+
+        /* Store results. */
+        vst1_u8(running_avg, vget_low_u8(v_running_avg));
+        vst1_u8(&running_avg[running_avg_stride], vget_high_u8(v_running_avg));
+
+        /* Sum all the accumulators to have the sum of all pixel differences
+         * for this macroblock.
+         */
+        {
+            const int8x16_t v_sum_diff =
+                vqsubq_s8(vreinterpretq_s8_u8(v_pos_adjustment),
+                          vreinterpretq_s8_u8(v_neg_adjustment));
+
+            const int16x8_t fe_dc_ba_98_76_54_32_10 = vpaddlq_s8(v_sum_diff);
+
+            const int32x4_t fedc_ba98_7654_3210 =
+                vpaddlq_s16(fe_dc_ba_98_76_54_32_10);
+
+            const int64x2_t fedcba98_76543210 =
+                vpaddlq_s32(fedc_ba98_7654_3210);
+
+            v_sum_diff_total = vqaddq_s64(v_sum_diff_total, fedcba98_76543210);
+        }
+
+        /* Update pointers for next iteration. */
+        sig += sig_stride * 2;
+        mc_running_avg += mc_running_avg_stride * 2;
+        running_avg += running_avg_stride * 2;
+    }
+
+
+    /* Too much adjustments => copy block. */
+    {
+        int64x1_t x = vqadd_s64(vget_high_s64(v_sum_diff_total),
+                                      vget_low_s64(v_sum_diff_total));
+        int sum_diff = vget_lane_s32(vabs_s32(vreinterpret_s32_s64(x)), 0);
+        int sum_diff_thresh = SUM_DIFF_THRESHOLD_UV;
+        if (increase_denoising) sum_diff_thresh = SUM_DIFF_THRESHOLD_HIGH_UV;
+        if (sum_diff > sum_diff_thresh) {
+          // Before returning to copy the block (i.e., apply no denoising),
+          // checK if we can still apply some (weaker) temporal filtering to
+          // this block, that would otherwise not be denoised at all. Simplest
+          // is to apply an additional adjustment to running_avg_y to bring it
+          // closer to sig. The adjustment is capped by a maximum delta, and
+          // chosen such that in most cases the resulting sum_diff will be
+          // within the accceptable range given by sum_diff_thresh.
+
+          // The delta is set by the excess of absolute pixel diff over the
+          // threshold.
+          int delta = ((sum_diff - sum_diff_thresh) >> 8) + 1;
+          // Only apply the adjustment for max delta up to 3.
+          if (delta < 4) {
+            const uint8x16_t k_delta = vmovq_n_u8(delta);
+            sig -= sig_stride * 8;
+            mc_running_avg -= mc_running_avg_stride * 8;
+            running_avg -= running_avg_stride * 8;
+            for (r = 0; r < 4; ++r) {
+              const uint8x8_t v_sig_lo = vld1_u8(sig);
+              const uint8x8_t v_sig_hi = vld1_u8(&sig[sig_stride]);
+              const uint8x16_t v_sig = vcombine_u8(v_sig_lo, v_sig_hi);
+              const uint8x8_t v_mc_running_avg_lo = vld1_u8(mc_running_avg);
+              const uint8x8_t v_mc_running_avg_hi =
+                  vld1_u8(&mc_running_avg[mc_running_avg_stride]);
+              const uint8x16_t v_mc_running_avg =
+                  vcombine_u8(v_mc_running_avg_lo, v_mc_running_avg_hi);
+              /* Calculate absolute difference and sign masks. */
+              const uint8x16_t v_abs_diff      = vabdq_u8(v_sig,
+                                                          v_mc_running_avg);
+              const uint8x16_t v_diff_pos_mask = vcltq_u8(v_sig,
+                                                          v_mc_running_avg);
+              const uint8x16_t v_diff_neg_mask = vcgtq_u8(v_sig,
+                                                          v_mc_running_avg);
+              // Clamp absolute difference to delta to get the adjustment.
+              const uint8x16_t v_abs_adjustment =
+                  vminq_u8(v_abs_diff, (k_delta));
+
+              const uint8x16_t v_pos_adjustment = vandq_u8(v_diff_pos_mask,
+                                                           v_abs_adjustment);
+              const uint8x16_t v_neg_adjustment = vandq_u8(v_diff_neg_mask,
+                                                           v_abs_adjustment);
+              const uint8x8_t v_running_avg_lo = vld1_u8(running_avg);
+              const uint8x8_t v_running_avg_hi =
+                  vld1_u8(&running_avg[running_avg_stride]);
+              uint8x16_t v_running_avg =
+                  vcombine_u8(v_running_avg_lo, v_running_avg_hi);
+
+              v_running_avg = vqsubq_u8(v_running_avg, v_pos_adjustment);
+              v_running_avg = vqaddq_u8(v_running_avg, v_neg_adjustment);
+
+              /* Store results. */
+              vst1_u8(running_avg, vget_low_u8(v_running_avg));
+              vst1_u8(&running_avg[running_avg_stride],
+                      vget_high_u8(v_running_avg));
+
+              {
+                  const int8x16_t v_sum_diff =
+                      vqsubq_s8(vreinterpretq_s8_u8(v_neg_adjustment),
+                                vreinterpretq_s8_u8(v_pos_adjustment));
+
+                  const int16x8_t fe_dc_ba_98_76_54_32_10 =
+                      vpaddlq_s8(v_sum_diff);
+                  const int32x4_t fedc_ba98_7654_3210 =
+                      vpaddlq_s16(fe_dc_ba_98_76_54_32_10);
+                  const int64x2_t fedcba98_76543210 =
+                      vpaddlq_s32(fedc_ba98_7654_3210);
+
+                  v_sum_diff_total = vqaddq_s64(v_sum_diff_total,
+                                                fedcba98_76543210);
+              }
+              /* Update pointers for next iteration. */
+              sig += sig_stride * 2;
+              mc_running_avg += mc_running_avg_stride * 2;
+              running_avg += running_avg_stride * 2;
+            }
+            {
+              // Update the sum of all pixel differences of this MB.
+              x = vqadd_s64(vget_high_s64(v_sum_diff_total),
+                            vget_low_s64(v_sum_diff_total));
+              sum_diff = vget_lane_s32(vabs_s32(vreinterpret_s32_s64(x)), 0);
+
+              if (sum_diff > sum_diff_thresh) {
+                return COPY_BLOCK;
+              }
+            }
+          } else {
+            return COPY_BLOCK;
+          }
+        }
+    }
+
+    /* Tell above level that block was filtered. */
+    running_avg -= running_avg_stride * 8;
+    sig -= sig_stride * 8;
+
+    vp8_copy_mem8x8(running_avg, running_avg_stride, sig, sig_stride);
+
+    return FILTER_BLOCK;
+}