1 files changed, 158 insertions, 0 deletions
diff --git a/media/libvpx/vp9/encoder/vp9_context_tree.c b/media/libvpx/vp9/encoder/vp9_context_tree.c
new file mode 100644
index 0000000000..f647ab3953
--- /dev/null
+++ b/media/libvpx/vp9/encoder/vp9_context_tree.c
@@ -0,0 +1,158 @@
+/*
+ *  Copyright (c) 2014 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 "vp9/encoder/vp9_context_tree.h"
+#include "vp9/encoder/vp9_encoder.h"
+
+static const BLOCK_SIZE square[] = {
+  BLOCK_8X8,
+  BLOCK_16X16,
+  BLOCK_32X32,
+  BLOCK_64X64,
+};
+
+static void alloc_mode_context(VP9_COMMON *cm, int num_4x4_blk,
+                               PICK_MODE_CONTEXT *ctx) {
+  const int num_blk = (num_4x4_blk < 4 ? 4 : num_4x4_blk);
+  const int num_pix = num_blk << 4;
+  int i, k;
+  ctx->num_4x4_blk = num_blk;
+
+  CHECK_MEM_ERROR(cm, ctx->zcoeff_blk,
+                  vpx_calloc(num_4x4_blk, sizeof(uint8_t)));
+  for (i = 0; i < MAX_MB_PLANE; ++i) {
+    for (k = 0; k < 3; ++k) {
+      CHECK_MEM_ERROR(cm, ctx->coeff[i][k],
+                      vpx_memalign(16, num_pix * sizeof(*ctx->coeff[i][k])));
+      CHECK_MEM_ERROR(cm, ctx->qcoeff[i][k],
+                      vpx_memalign(16, num_pix * sizeof(*ctx->qcoeff[i][k])));
+      CHECK_MEM_ERROR(cm, ctx->dqcoeff[i][k],
+                      vpx_memalign(16, num_pix * sizeof(*ctx->dqcoeff[i][k])));
+      CHECK_MEM_ERROR(cm, ctx->eobs[i][k],
+                      vpx_memalign(16, num_pix * sizeof(*ctx->eobs[i][k])));
+      ctx->coeff_pbuf[i][k]   = ctx->coeff[i][k];
+      ctx->qcoeff_pbuf[i][k]  = ctx->qcoeff[i][k];
+      ctx->dqcoeff_pbuf[i][k] = ctx->dqcoeff[i][k];
+      ctx->eobs_pbuf[i][k]    = ctx->eobs[i][k];
+    }
+  }
+}
+
+static void free_mode_context(PICK_MODE_CONTEXT *ctx) {
+  int i, k;
+  vpx_free(ctx->zcoeff_blk);
+  ctx->zcoeff_blk = 0;
+  for (i = 0; i < MAX_MB_PLANE; ++i) {
+    for (k = 0; k < 3; ++k) {
+      vpx_free(ctx->coeff[i][k]);
+      ctx->coeff[i][k] = 0;
+      vpx_free(ctx->qcoeff[i][k]);
+      ctx->qcoeff[i][k] = 0;
+      vpx_free(ctx->dqcoeff[i][k]);
+      ctx->dqcoeff[i][k] = 0;
+      vpx_free(ctx->eobs[i][k]);
+      ctx->eobs[i][k] = 0;
+    }
+  }
+}
+
+static void alloc_tree_contexts(VP9_COMMON *cm, PC_TREE *tree,
+                                int num_4x4_blk) {
+  alloc_mode_context(cm, num_4x4_blk, &tree->none);
+  alloc_mode_context(cm, num_4x4_blk/2, &tree->horizontal[0]);
+  alloc_mode_context(cm, num_4x4_blk/2, &tree->vertical[0]);
+
+  /* TODO(Jbb): for 4x8 and 8x4 these allocated values are not used.
+   * Figure out a better way to do this. */
+  alloc_mode_context(cm, num_4x4_blk/2, &tree->horizontal[1]);
+  alloc_mode_context(cm, num_4x4_blk/2, &tree->vertical[1]);
+}
+
+static void free_tree_contexts(PC_TREE *tree) {
+  free_mode_context(&tree->none);
+  free_mode_context(&tree->horizontal[0]);
+  free_mode_context(&tree->horizontal[1]);
+  free_mode_context(&tree->vertical[0]);
+  free_mode_context(&tree->vertical[1]);
+}
+
+// This function sets up a tree of contexts such that at each square
+// partition level. There are contexts for none, horizontal, vertical, and
+// split.  Along with a block_size value and a selected block_size which
+// represents the state of our search.
+void vp9_setup_pc_tree(VP9_COMMON *cm, ThreadData *td) {
+  int i, j;
+  const int leaf_nodes = 64;
+  const int tree_nodes = 64 + 16 + 4 + 1;
+  int pc_tree_index = 0;
+  PC_TREE *this_pc;
+  PICK_MODE_CONTEXT *this_leaf;
+  int square_index = 1;
+  int nodes;
+
+  vpx_free(td->leaf_tree);
+  CHECK_MEM_ERROR(cm, td->leaf_tree, vpx_calloc(leaf_nodes,
+                                                sizeof(*td->leaf_tree)));
+  vpx_free(td->pc_tree);
+  CHECK_MEM_ERROR(cm, td->pc_tree, vpx_calloc(tree_nodes,
+                                              sizeof(*td->pc_tree)));
+
+  this_pc = &td->pc_tree[0];
+  this_leaf = &td->leaf_tree[0];
+
+  // 4x4 blocks smaller than 8x8 but in the same 8x8 block share the same
+  // context so we only need to allocate 1 for each 8x8 block.
+  for (i = 0; i < leaf_nodes; ++i)
+    alloc_mode_context(cm, 1, &td->leaf_tree[i]);
+
+  // Sets up all the leaf nodes in the tree.
+  for (pc_tree_index = 0; pc_tree_index < leaf_nodes; ++pc_tree_index) {
+    PC_TREE *const tree = &td->pc_tree[pc_tree_index];
+    tree->block_size = square[0];
+    alloc_tree_contexts(cm, tree, 4);
+    tree->leaf_split[0] = this_leaf++;
+    for (j = 1; j < 4; j++)
+      tree->leaf_split[j] = tree->leaf_split[0];
+  }
+
+  // Each node has 4 leaf nodes, fill each block_size level of the tree
+  // from leafs to the root.
+  for (nodes = 16; nodes > 0; nodes >>= 2) {
+    for (i = 0; i < nodes; ++i) {
+      PC_TREE *const tree = &td->pc_tree[pc_tree_index];
+      alloc_tree_contexts(cm, tree, 4 << (2 * square_index));
+      tree->block_size = square[square_index];
+      for (j = 0; j < 4; j++)
+        tree->split[j] = this_pc++;
+      ++pc_tree_index;
+    }
+    ++square_index;
+  }
+  td->pc_root = &td->pc_tree[tree_nodes - 1];
+  td->pc_root[0].none.best_mode_index = 2;
+}
+
+void vp9_free_pc_tree(ThreadData *td) {
+  const int tree_nodes = 64 + 16 + 4 + 1;
+  int i;
+
+  // Set up all 4x4 mode contexts
+  for (i = 0; i < 64; ++i)
+    free_mode_context(&td->leaf_tree[i]);
+
+  // Sets up all the leaf nodes in the tree.
+  for (i = 0; i < tree_nodes; ++i)
+    free_tree_contexts(&td->pc_tree[i]);
+
+  vpx_free(td->pc_tree);
+  td->pc_tree = NULL;
+  vpx_free(td->leaf_tree);
+  td->leaf_tree = NULL;
+}