From: jackychen <jackychen@google.com>
Date: Wed, 7 Oct 2015 22:08:20 +0000 (-0700)
Subject: VP9 denoiser: use skin map to improve denoising.
X-Git-Tag: v1.5.0~60^2
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=bafe1a2d67d85fc0a4b6fe5574aabac4503fbd28;p=libvpx

VP9 denoiser: use skin map to improve denoising.

Only denoise at small motion if it's a skin block.

Change-Id: I6235cad9dd7f76ab40e7d9cdfe6180e619c20c6e
---

diff --git a/vp9/encoder/vp9_denoiser.c b/vp9/encoder/vp9_denoiser.c
index 4cac388ba..678e3123f 100644
--- a/vp9/encoder/vp9_denoiser.c
+++ b/vp9/encoder/vp9_denoiser.c
@@ -195,8 +195,8 @@ static VP9_DENOISER_DECISION perform_motion_compensation(VP9_DENOISER *denoiser,
                                                          int mi_row,
                                                          int mi_col,
                                                          PICK_MODE_CONTEXT *ctx,
-                                                         int *motion_magnitude
-                                                         ) {
+                                                         int *motion_magnitude,
+                                                         int is_skin) {
   int mv_col, mv_row;
   int sse_diff = ctx->zeromv_sse - ctx->newmv_sse;
   MV_REFERENCE_FRAME frame;
@@ -214,6 +214,9 @@ static VP9_DENOISER_DECISION perform_motion_compensation(VP9_DENOISER *denoiser,
 
   saved_mbmi = *mbmi;
 
+  if (is_skin && *motion_magnitude > 16)
+    return COPY_BLOCK;
+
   // If the best reference frame uses inter-prediction and there is enough of a
   // difference in sum-squared-error, use it.
   if (frame != INTRA_FRAME &&
@@ -313,18 +316,37 @@ void vp9_denoiser_denoise(VP9_DENOISER *denoiser, MACROBLOCK *mb,
                           int mi_row, int mi_col, BLOCK_SIZE bs,
                           PICK_MODE_CONTEXT *ctx) {
   int motion_magnitude = 0;
-  VP9_DENOISER_DECISION decision = FILTER_BLOCK;
+  VP9_DENOISER_DECISION decision = COPY_BLOCK;
   YV12_BUFFER_CONFIG avg = denoiser->running_avg_y[INTRA_FRAME];
   YV12_BUFFER_CONFIG mc_avg = denoiser->mc_running_avg_y;
   uint8_t *avg_start = block_start(avg.y_buffer, avg.y_stride, mi_row, mi_col);
   uint8_t *mc_avg_start = block_start(mc_avg.y_buffer, mc_avg.y_stride,
                                           mi_row, mi_col);
   struct buf_2d src = mb->plane[0].src;
+  int is_skin = 0;
+
+  if (bs <= BLOCK_16X16) {
+    // Take center pixel in block to determine is_skin.
+    const int y_width_shift = (4 << b_width_log2_lookup[bs]) >> 1;
+    const int y_height_shift = (4 << b_height_log2_lookup[bs]) >> 1;
+    const int uv_width_shift = y_width_shift >> 1;
+    const int uv_height_shift = y_height_shift >> 1;
+    const int stride = mb->plane[0].src.stride;
+    const int strideuv = mb->plane[1].src.stride;
+    const uint8_t ysource =
+      mb->plane[0].src.buf[y_height_shift * stride + y_width_shift];
+    const uint8_t usource =
+      mb->plane[1].src.buf[uv_height_shift * strideuv + uv_width_shift];
+    const uint8_t vsource =
+      mb->plane[2].src.buf[uv_height_shift * strideuv + uv_width_shift];
+    is_skin = vp9_skin_pixel(ysource, usource, vsource);
+  }
 
   decision = perform_motion_compensation(denoiser, mb, bs,
                                          denoiser->increase_denoising,
                                          mi_row, mi_col, ctx,
-                                         &motion_magnitude);
+                                         &motion_magnitude,
+                                         is_skin);
 
   if (decision == FILTER_BLOCK) {
     decision = vp9_denoiser_filter(src.buf, src.stride,
diff --git a/vp9/encoder/vp9_denoiser.h b/vp9/encoder/vp9_denoiser.h
index c66fdf426..ec0b25e01 100644
--- a/vp9/encoder/vp9_denoiser.h
+++ b/vp9/encoder/vp9_denoiser.h
@@ -12,6 +12,7 @@
 #define VP9_ENCODER_DENOISER_H_
 
 #include "vp9/encoder/vp9_block.h"
+#include "vp9/encoder/vp9_skin_detection.h"
 #include "vpx_scale/yv12config.h"
 
 #ifdef __cplusplus