From 6e122b6f825a4d043214f53c0d8437d91b7b2457 Mon Sep 17 00:00:00 2001
From: Dan Zhu <zxdan@google.com>
Date: Wed, 14 Aug 2019 13:51:29 -0700
Subject: [PATCH] estimate local variation of reference frame

Change-Id: I4218057403ad4f565ee2dcb5403ecaae17af7e26
---
 vp9/encoder/vp9_non_greedy_mv.c | 50 +++++++++++++++++++++++++++++++++
 vp9/encoder/vp9_non_greedy_mv.h |  9 ++++++
 2 files changed, 59 insertions(+)

diff --git a/vp9/encoder/vp9_non_greedy_mv.c b/vp9/encoder/vp9_non_greedy_mv.c
index 04b7a4a2c..8022c6103 100644
--- a/vp9/encoder/vp9_non_greedy_mv.c
+++ b/vp9/encoder/vp9_non_greedy_mv.c
@@ -295,3 +295,53 @@ void vp9_get_smooth_motion_field(const MV *scaled_search_mf, const int (*M)[4],
   free(input);
   free(output);
 }
+
+void vp9_get_local_structure(const YV12_BUFFER_CONFIG *ref_frame,
+                             const vp9_variance_fn_ptr_t *fn_ptr, int mi_rows,
+                             int mi_cols, BLOCK_SIZE bsize, int (*M)[4]) {
+  int stride = ref_frame->y_stride;
+  const int mi_height = num_8x8_blocks_high_lookup[bsize];
+  const int mi_width = num_8x8_blocks_wide_lookup[bsize];
+  int cols = mi_cols / mi_width;
+  int mi_row, mi_col;
+  for (mi_row = 0; mi_row < mi_rows; mi_row += mi_height) {
+    for (mi_col = 0; mi_col < mi_cols; mi_col += mi_width) {
+      const int mb_y_offset = mi_row * MI_SIZE * stride + mi_col * MI_SIZE;
+      int row = mi_row / mi_height;
+      int col = mi_col / mi_width;
+      uint8_t *center = ref_frame->y_buffer + mb_y_offset;
+      uint8_t *nb;
+      int I_row = 0, I_col = 0;
+      // up
+      if (mi_row > 0) {
+        nb = center - MI_SIZE * stride * mi_height;
+        I_row += fn_ptr->sdf(center, stride, nb, stride);
+      }
+      // down
+      if (mi_row < mi_rows - 1) {
+        nb = center + MI_SIZE * stride * mi_height;
+        I_row += fn_ptr->sdf(center, stride, nb, stride);
+      }
+      if (mi_row > 0 && mi_row < mi_rows - 1) {
+        I_row /= 2;
+      }
+      // left
+      if (mi_col > 0) {
+        nb = center - MI_SIZE * mi_width;
+        I_col += fn_ptr->sdf(center, stride, nb, stride);
+      }
+      // right
+      if (mi_col < mi_cols - 1) {
+        nb = center + MI_SIZE * mi_width;
+        I_col += fn_ptr->sdf(center, stride, nb, stride);
+      }
+      if (mi_col > 0 && mi_col < mi_cols - 1) {
+        I_col /= 2;
+      }
+      M[row * cols + col][0] = I_row * I_row;
+      M[row * cols + col][1] = I_row * I_col;
+      M[row * cols + col][2] = I_col * I_row;
+      M[row * cols + col][3] = I_col * I_col;
+    }
+  }
+}
diff --git a/vp9/encoder/vp9_non_greedy_mv.h b/vp9/encoder/vp9_non_greedy_mv.h
index b70470323..5230ba375 100644
--- a/vp9/encoder/vp9_non_greedy_mv.h
+++ b/vp9/encoder/vp9_non_greedy_mv.h
@@ -11,6 +11,11 @@
 #ifndef VPX_VP9_ENCODER_VP9_NON_GREEDY_MV_H_
 #define VPX_VP9_ENCODER_VP9_NON_GREEDY_MV_H_
 
+#include "vp9/common/vp9_enums.h"
+#include "vp9/common/vp9_blockd.h"
+#include "vpx_scale/yv12config.h"
+#include "vpx_dsp/variance.h"
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -24,6 +29,10 @@ void vp9_get_smooth_motion_field(const MV *search_mf, const int (*M)[4],
                                  int rows, int cols, float alpha, int num_iters,
                                  MV *smooth_mf);
 
+void vp9_get_local_structure(const YV12_BUFFER_CONFIG *ref_frame,
+                             const vp9_variance_fn_ptr_t *fn_ptr, int mi_rows,
+                             int mi_cols, BLOCK_SIZE bsize, int (*M)[4]);
+
 #ifdef __cplusplus
 }  // extern "C"
 #endif
-- 
2.40.0