ref: b52db6b7e8ca2b49d09500cdf599a2f15b8baedd
parent: cdc933ca0043b7944a4a45edb85d4c142f63fc56
author: Christian Duvivier <cduvivier@google.com>
date: Wed Jan 1 13:46:47 EST 2014
ARM NEON version of denoiser. Change-Id: I951abd4ad0078f78949f3cb79453ac334fb82a7e
--- a/vp8/common/rtcd_defs.sh
+++ b/vp8/common/rtcd_defs.sh
@@ -535,7 +535,7 @@
#
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
--- /dev/null
+++ b/vp8/encoder/arm/neon/denoising_neon.c
@@ -1,0 +1,165 @@
+/*
+ * 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;
+}
--- a/vp8/vp8cx_arm.mk
+++ b/vp8/vp8cx_arm.mk
@@ -37,6 +37,7 @@
# 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)