Merge "ARM NEON version of denoiser."

vp8/common/rtcd_defs.sh

@@ -535,7 +535,7 @@ specialize vp8_yv12_copy_partial_frame neon
 #
 if [ "$CONFIG_TEMPORAL_DENOISING" = "yes" ]; then
     prototype int vp8_denoiser_filter "struct yv12_buffer_config* mc_running_avg, struct yv12_buffer_config* running_avg, struct macroblock* signal, unsigned int motion_magnitude2, int y_offset, int uv_offset"
-    specialize vp8_denoiser_filter sse2
+    specialize vp8_denoiser_filter sse2 neon
 fi
 
 # End of encoder only functions

vp8/encoder/arm/neon/denoising_neon.c

+/*
+ *  Copyright (c) 2012 The WebM project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include <arm_neon.h>
+
+#include "vp8/encoder/denoising.h"
+#include "vpx_mem/vpx_mem.h"
+#include "./vp8_rtcd.h"
+
+/*
+ * The filter function was modified to reduce the computational complexity.
+ *
+ * Step 1:
+ *  Instead of applying tap coefficients for each pixel, we calculated the
+ *  pixel adjustments vs. pixel diff value ahead of time.
+ *     adjustment = filtered_value - current_raw
+ *                = (filter_coefficient * diff + 128) >> 8
+ *  where
+ *     filter_coefficient = (255 << 8) / (256 + ((abs_diff * 330) >> 3));
+ *     filter_coefficient += filter_coefficient /
+ *                           (3 + motion_magnitude_adjustment);
+ *     filter_coefficient is clamped to 0 ~ 255.
+ *
+ * Step 2:
+ *  The adjustment vs. diff curve becomes flat very quick when diff increases.
+ *  This allowed us to use only several levels to approximate the curve without
+ *  changing the filtering algorithm too much.
+ *  The adjustments were further corrected by checking the motion magnitude.
+ *  The levels used are:
+ *      diff          level       adjustment w/o       adjustment w/
+ *                               motion correction    motion correction
+ *      [-255, -16]     3              -6                   -7
+ *      [-15, -8]       2              -4                   -5
+ *      [-7, -4]        1              -3                   -4
+ *      [-3, 3]         0              diff                 diff
+ *      [4, 7]          1               3                    4
+ *      [8, 15]         2               4                    5
+ *      [16, 255]       3               6                    7
+ */
+
+int vp8_denoiser_filter_neon(YV12_BUFFER_CONFIG *mc_running_avg,
+                             YV12_BUFFER_CONFIG *running_avg,
+                             MACROBLOCK *signal, unsigned int motion_magnitude,
+                             int y_offset, int uv_offset) {
+    /* 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.
+     */
+    const uint8x16_t v_level1_adjustment = vdupq_n_u8(
+        (motion_magnitude <= MOTION_MAGNITUDE_THRESHOLD) ? 4 : 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 = vdupq_n_u8(4);
+    const uint8x16_t v_level2_threshold = vdupq_n_u8(8);
+    const uint8x16_t v_level3_threshold = vdupq_n_u8(16);
+
+    /* Local variables for array pointers and strides. */
+    unsigned char *sig = signal->thismb;
+    int            sig_stride = 16;
+    unsigned char *mc_running_avg_y = mc_running_avg->y_buffer + y_offset;
+    int            mc_running_avg_y_stride = mc_running_avg->y_stride;
+    unsigned char *running_avg_y = running_avg->y_buffer + y_offset;
+    int            running_avg_y_stride = running_avg->y_stride;
+
+    /* Go over lines. */
+    int i;
+    int sum_diff = 0;
+    for (i = 0; i < 16; ++i) {
+        int8x16_t v_sum_diff = vdupq_n_s8(0);
+        uint8x16_t v_running_avg_y;
+
+        /* Load inputs. */
+        const uint8x16_t v_sig = vld1q_u8(sig);
+        const uint8x16_t v_mc_running_avg_y = vld1q_u8(mc_running_avg_y);
+
+        /* Calculate absolute difference and sign masks. */
+        const uint8x16_t v_abs_diff      = vabdq_u8(v_sig, v_mc_running_avg_y);
+        const uint8x16_t v_diff_pos_mask = vcltq_u8(v_sig, v_mc_running_avg_y);
+        const uint8x16_t v_diff_neg_mask = vcgtq_u8(v_sig, v_mc_running_avg_y);
+
+        /* 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);
+        v_running_avg_y = vqaddq_u8(v_sig, v_pos_adjustment);
+        v_running_avg_y = vqsubq_u8(v_running_avg_y, v_neg_adjustment);
+        v_sum_diff = vqaddq_s8(v_sum_diff, (int8x16_t)v_pos_adjustment);
+        v_sum_diff = vqsubq_s8(v_sum_diff, (int8x16_t)v_neg_adjustment);
+
+        /* Store results. */
+        vst1q_u8(running_avg_y, v_running_avg_y);
+
+        /* Sum all the accumulators to have the sum of all pixel differences
+         * for this macroblock.
+         */
+        {
+            int s0 = vgetq_lane_s8(v_sum_diff,  0) +
+                     vgetq_lane_s8(v_sum_diff,  1) +
+                     vgetq_lane_s8(v_sum_diff,  2) +
+                     vgetq_lane_s8(v_sum_diff,  3);
+            int s1 = vgetq_lane_s8(v_sum_diff,  4) +
+                     vgetq_lane_s8(v_sum_diff,  5) +
+                     vgetq_lane_s8(v_sum_diff,  6) +
+                     vgetq_lane_s8(v_sum_diff,  7);
+            int s2 = vgetq_lane_s8(v_sum_diff,  8) +
+                     vgetq_lane_s8(v_sum_diff,  9) +
+                     vgetq_lane_s8(v_sum_diff, 10) +
+                     vgetq_lane_s8(v_sum_diff, 11);
+            int s3 = vgetq_lane_s8(v_sum_diff, 12) +
+                     vgetq_lane_s8(v_sum_diff, 13) +
+                     vgetq_lane_s8(v_sum_diff, 14) +
+                     vgetq_lane_s8(v_sum_diff, 15);
+            sum_diff += s0 + s1+ s2 + s3;
+        }
+
+        /* Update pointers for next iteration. */
+        sig += sig_stride;
+        mc_running_avg_y += mc_running_avg_y_stride;
+        running_avg_y += running_avg_y_stride;
+    }
+
+    /* Too much adjustments => copy block. */
+    if (abs(sum_diff) > SUM_DIFF_THRESHOLD)
+        return COPY_BLOCK;
+
+    /* Tell above level that block was filtered. */
+    vp8_copy_mem16x16(running_avg->y_buffer + y_offset, running_avg_y_stride,
+                      signal->thismb, sig_stride);
+    return FILTER_BLOCK;
+}

vp8/vp8cx_arm.mk

@@ -37,6 +37,7 @@ VP8_CX_SRCS-$(HAVE_MEDIA)  += encoder/arm/armv6/walsh_v6$(ASM)
 # encoder
 VP8_CX_SRCS-$(HAVE_NEON)  += encoder/arm/neon/fastquantizeb_neon$(ASM)
 VP8_CX_SRCS-$(HAVE_NEON)  += encoder/arm/neon/picklpf_arm.c
+VP8_CX_SRCS-$(HAVE_NEON)  += encoder/arm/neon/denoising_neon.c
 VP8_CX_SRCS-$(HAVE_NEON)  += encoder/arm/neon/shortfdct_neon$(ASM)
 VP8_CX_SRCS-$(HAVE_NEON)  += encoder/arm/neon/subtract_neon$(ASM)
 VP8_CX_SRCS-$(HAVE_NEON)  += encoder/arm/neon/vp8_mse16x16_neon$(ASM)