diff --git a/configure b/configure
index c96ddb3cca02ec5858cb969bae410542245194c3..d01c5ff2380b03ba99a7bf697f1e219b14881d82 100755
--- a/configure
+++ b/configure
@@ -25,6 +25,7 @@ Advanced options:
   ${toggle_analyzer}              analyzer
   ${toggle_docs}                  documentation
   ${toggle_unit_tests}            unit tests
+  ${toggle_tools}                 tools
   ${toggle_decode_perf_tests}     build decoder perf tests with unit tests
   ${toggle_encode_perf_tests}     build encoder perf tests with unit tests
   --cpu=CPU                       tune for the specified CPU (ARM: cortex-a8, X86: sse3)
@@ -146,7 +147,7 @@ all_platforms="${all_platforms} generic-gnu"
 
 # all_targets is a list of all targets that can be configured
 # note that these should be in dependency order for now.
-all_targets="libs examples docs"
+all_targets="libs examples docs tools"
 
 # all targets available are enabled, by default.
 for t in ${all_targets}; do
@@ -399,6 +400,7 @@ CMDLINE_SELECT="
     examples
     analyzer
     docs
+    tools
     libc
     as
     size_limit
@@ -636,7 +638,7 @@ EOF
     #
     # Write makefiles for all enabled targets
     #
-    for tgt in libs examples docs solution; do
+    for tgt in libs examples docs tools solution; do
         tgt_fn="$tgt-$toolchain.mk"
 
         if enabled $tgt; then
diff --git a/tools.mk b/tools.mk
new file mode 100644
index 0000000000000000000000000000000000000000..26c20d433a8fd2c98744bd5df5d58302d67a6670
--- /dev/null
+++ b/tools.mk
@@ -0,0 +1,126 @@
+##
+## Copyright (c) 2017, Alliance for Open Media. All rights reserved
+##
+## This source code is subject to the terms of the BSD 2 Clause License and
+## the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
+## was not distributed with this source code in the LICENSE file, you can
+## obtain it at www.aomedia.org/license/software. If the Alliance for Open
+## Media Patent License 1.0 was not distributed with this source code in the
+## PATENTS file, you can obtain it at www.aomedia.org/license/patent.
+##
+
+# List of tools to build.
+ifeq ($(CONFIG_ENTROPY_STATS), yes)
+TOOLS-$(CONFIG_AV1_ENCODER)      += aom_entropy_optimizer.c
+aom_entropy_optimizer.GUID        = 3afa9b05-940b-4d68-b5aa-55157d8ed7b4
+aom_entropy_optimizer.DESCRIPTION = Offline default probability optimizer
+endif
+
+#
+# End of specified files. The rest of the build rules should happen
+# automagically from here.
+#
+
+# Tools need different flags based on whether we're building
+# from an installed tree or a version controlled tree. Determine
+# the proper paths.
+ifeq ($(HAVE_ALT_TREE_LAYOUT),yes)
+    LIB_PATH-yes := $(SRC_PATH_BARE)/../lib
+    INC_PATH-yes := $(SRC_PATH_BARE)/../include
+else
+    LIB_PATH-yes                     += $(if $(BUILD_PFX),$(BUILD_PFX),.)
+    INC_PATH-$(CONFIG_AV1_DECODER)   += $(SRC_PATH_BARE)/av1
+    INC_PATH-$(CONFIG_AV1_ENCODER)   += $(SRC_PATH_BARE)/av1
+endif
+INC_PATH-$(CONFIG_LIBYUV) += $(SRC_PATH_BARE)/third_party/libyuv/include
+LIB_PATH := $(call enabled,LIB_PATH)
+INC_PATH := $(call enabled,INC_PATH)
+INTERNAL_CFLAGS = $(addprefix -I,$(INC_PATH))
+INTERNAL_LDFLAGS += $(addprefix -L,$(LIB_PATH))
+
+# Expand list of selected tools to build (as specified above)
+TOOLS           = $(addprefix tools/,$(call enabled,TOOLS))
+ALL_SRCS        = $(foreach ex,$(TOOLS),$($(notdir $(ex:.c=)).SRCS))
+CFLAGS += -I../include
+CODEC_EXTRA_LIBS=$(sort $(call enabled,CODEC_EXTRA_LIBS))
+
+ifneq ($(CONFIG_CODEC_SRCS), yes)
+  CFLAGS += -I../include/vpx
+endif
+
+# Expand all tools sources into a variable containing all sources
+# for that tools (not just them main one specified in TOOLS)
+# and add this file to the list (for MSVS workspace generation)
+$(foreach ex,$(TOOLS),$(eval $(notdir $(ex:.c=)).SRCS += $(ex) tools.mk))
+
+
+# Create build/install dependencies for all tools. The common case
+# is handled here. The MSVS case is handled below.
+NOT_MSVS = $(if $(CONFIG_MSVS),,yes)
+DIST-BINS-$(NOT_MSVS)      += $(addprefix bin/,$(TOOLS:.c=$(EXE_SFX)))
+DIST-SRCS-yes              += $(ALL_SRCS)
+OBJS-$(NOT_MSVS)           += $(call objs,$(ALL_SRCS))
+BINS-$(NOT_MSVS)           += $(addprefix $(BUILD_PFX),$(TOOLS:.c=$(EXE_SFX)))
+
+# Instantiate linker template for all tools.
+ifeq ($(CONFIG_OS_SUPPORT), yes)
+CODEC_EXTRA_LIBS-$(CONFIG_AV1)            += m
+else
+    ifeq ($(CONFIG_GCC), yes)
+    CODEC_EXTRA_LIBS-$(CONFIG_AV1)        += m
+    endif
+endif
+
+CODEC_LIB=$(if $(CONFIG_DEBUG_LIBS),aom_g,aom)
+ifneq ($(filter darwin%,$(TGT_OS)),)
+SHARED_LIB_SUF=.dylib
+else
+ifneq ($(filter os2%,$(TGT_OS)),)
+SHARED_LIB_SUF=_dll.a
+else
+SHARED_LIB_SUF=.so
+endif
+endif
+CODEC_LIB_SUF=$(if $(CONFIG_SHARED),$(SHARED_LIB_SUF),.a)
+$(foreach bin,$(BINS-yes),\
+    $(eval $(bin):$(LIB_PATH)/lib$(CODEC_LIB)$(CODEC_LIB_SUF))\
+    $(eval $(call linker_template,$(bin),\
+        $(call objs,$($(notdir $(bin:$(EXE_SFX)=)).SRCS)) \
+        -l$(CODEC_LIB) $(addprefix -l,$(CODEC_EXTRA_LIBS))\
+        )))
+
+# The following pairs define a mapping of locations in the distribution
+# tree to locations in the source/build trees.
+INSTALL_MAPS += src/%.c   %.c
+INSTALL_MAPS += src/%     $(SRC_PATH_BARE)/%
+INSTALL_MAPS += bin/%     %
+INSTALL_MAPS += %         %
+
+
+# Build Visual Studio Projects. We use a template here to instantiate
+# explicit rules rather than using an implicit rule because we want to
+# leverage make's VPATH searching rather than specifying the paths on
+# each file in TOOLS. This has the unfortunate side effect that
+# touching the source files trigger a rebuild of the project files
+# even though there is no real dependency there (the dependency is on
+# the makefiles). We may want to revisit this.
+define vcproj_template
+$(1): $($(1:.$(VCPROJ_SFX)=).SRCS) vpx.$(VCPROJ_SFX)
+	$(if $(quiet),@echo "    [vcproj] $$@")
+	$(qexec)$$(GEN_VCPROJ)\
+            --exe\
+            --target=$$(TOOLCHAIN)\
+            --name=$$(@:.$(VCPROJ_SFX)=)\
+            --ver=$$(CONFIG_VS_VERSION)\
+            --proj-guid=$$($$(@:.$(VCPROJ_SFX)=).GUID)\
+            --src-path-bare="$(SRC_PATH_BARE)" \
+            $$(if $$(CONFIG_STATIC_MSVCRT),--static-crt) \
+            --out=$$@ $$(INTERNAL_CFLAGS) $$(CFLAGS) \
+            $$(INTERNAL_LDFLAGS) $$(LDFLAGS) $$^
+endef
+TOOLS_BASENAME := $(notdir $(TOOLS))
+PROJECTS-$(CONFIG_MSVS) += $(TOOLS_BASENAME:.c=.$(VCPROJ_SFX))
+INSTALL-BINS-$(CONFIG_MSVS) += $(foreach p,$(VS_PLATFORMS),\
+                               $(addprefix bin/$(p)/,$(TOOLS_BASENAME:.c=.exe)))
+$(foreach proj,$(call enabled,PROJECTS),\
+    $(eval $(call vcproj_template,$(proj))))
diff --git a/tools/aom_entropy_optimizer.c b/tools/aom_entropy_optimizer.c
new file mode 100644
index 0000000000000000000000000000000000000000..63703ebd16ee79b76b34b0cba8b1267509fdf2cc
--- /dev/null
+++ b/tools/aom_entropy_optimizer.c
@@ -0,0 +1,512 @@
+/*
+ * Copyright (c) 2017, Alliance for Open Media. All rights reserved
+ *
+ * This source code is subject to the terms of the BSD 2 Clause License and
+ * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
+ * was not distributed with this source code in the LICENSE file, you can
+ * obtain it at www.aomedia.org/license/software. If the Alliance for Open
+ * Media Patent License 1.0 was not distributed with this source code in the
+ * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
+ */
+
+// This tool is a gadget for offline probability training.
+// A binary executable aom_entropy_optimizer will be generated in tools/. It
+// parses a binary file consisting of counts written in the format of
+// FRAME_COUNTS in entropymode.h, and computes the optimized probability table,
+// which will be written to a new c file optimized_probs.c according to format
+// of entropymode.c file.
+//
+// Command line: ./aom_entropy_optimizer [directory of the count file]
+//
+// The input file can either be generated by encoding a single clip by
+// turning on entropy_stats experiment, or be collected at a larger scale at
+// which a python script which will be provided soon can be used to aggregate
+// multiple stats output.
+
+#include <assert.h>
+#include <stdio.h>
+#include "./aom_config.h"
+#include "av1/common/entropymode.h"
+
+#define SPACES_PER_TAB 2
+
+typedef unsigned int aom_count_type;
+// A log file recording parsed counts
+static FILE *logfile;  // TODO(yuec): make it a command line option
+
+// Optimized probabilities will be stored in probs[].
+static INLINE unsigned int optimize_tree_probs(const aom_tree_index *tree,
+                                               unsigned int idx,
+                                               const unsigned int *counts,
+                                               aom_prob *probs) {
+  const int l = tree[idx];
+  const unsigned int left_count =
+      (l <= 0) ? counts[-l] : optimize_tree_probs(tree, l, counts, probs);
+  const int r = tree[idx + 1];
+  const unsigned int right_count =
+      (r <= 0) ? counts[-r] : optimize_tree_probs(tree, r, counts, probs);
+  probs[idx >> 1] = get_binary_prob(left_count, right_count);
+  return left_count + right_count;
+}
+
+static int parse_stats(aom_count_type **ct_ptr, FILE *const probsfile, int tabs,
+                       int dim_of_cts, int *cts_each_dim,
+                       const aom_tree_index *tree, int flatten_last_dim) {
+  if (dim_of_cts < 1) {
+    fprintf(stderr, "The dimension of a counts vector should be at least 1!\n");
+    return 1;
+  }
+  if (dim_of_cts == 1) {
+    const int total_modes = cts_each_dim[0];
+    aom_count_type *counts1d = *ct_ptr;
+    aom_prob *probs = aom_malloc(sizeof(*probs) * (total_modes - 1));
+
+    if (probs == NULL) {
+      fprintf(stderr, "Allocating prob array failed!\n");
+      return 1;
+    }
+
+    (*ct_ptr) += total_modes;
+    if (tree != NULL) {
+      optimize_tree_probs(tree, 0, counts1d, probs);
+    } else {
+      assert(total_modes == 2);
+      probs[0] = get_binary_prob(counts1d[0], counts1d[1]);
+    }
+    if (tabs > 0) fprintf(probsfile, "%*c", tabs * SPACES_PER_TAB, ' ');
+    for (int k = 0; k < total_modes - 1; ++k) {
+      fprintf(probsfile, " %3d,", probs[k]);
+      fprintf(logfile, "%d ", counts1d[k]);
+    }
+    fprintf(logfile, "%d\n", counts1d[total_modes - 1]);
+  } else if (dim_of_cts == 2 && flatten_last_dim) {
+    assert(cts_each_dim[1] == 2);
+
+    for (int k = 0; k < cts_each_dim[0]; ++k) {
+      fprintf(probsfile, " %3d,", get_binary_prob((*ct_ptr)[0], (*ct_ptr)[1]));
+      fprintf(logfile, "%d %d\n", (*ct_ptr)[0], (*ct_ptr)[1]);
+      (*ct_ptr) += 2;
+    }
+  } else {
+    for (int k = 0; k < cts_each_dim[0]; ++k) {
+      int tabs_next_level;
+      if (dim_of_cts == 2 || (dim_of_cts == 3 && flatten_last_dim)) {
+        fprintf(probsfile, "%*c{", tabs * SPACES_PER_TAB, ' ');
+        tabs_next_level = 0;
+      } else {
+        fprintf(probsfile, "%*c{\n", tabs * SPACES_PER_TAB, ' ');
+        tabs_next_level = tabs + 1;
+      }
+      if (parse_stats(ct_ptr, probsfile, tabs_next_level, dim_of_cts - 1,
+                      cts_each_dim + 1, tree, flatten_last_dim)) {
+        return 1;
+      }
+      if (dim_of_cts == 2 || (dim_of_cts == 3 && flatten_last_dim)) {
+        fprintf(probsfile, "},\n");
+      } else {
+        fprintf(probsfile, "%*c},\n", tabs * SPACES_PER_TAB, ' ');
+      }
+    }
+  }
+  return 0;
+}
+
+// This function parses the stats of a syntax, either binary or multi-symbol,
+// in different contexts, and writes the optimized probability table to
+// probsfile.
+//   counts: pointer of the first count element in counts array
+//   probsfile: output file
+//   dim_of_cts: number of dimensions of counts array
+//   cts_each_dim: an array storing size of each dimension of counts array
+//   tree: binary tree for a multi-symbol syntax, or NULL for a binary one
+//   flatten_last_dim: for a binary syntax, if flatten_last_dim is 0, probs in
+//                     different contexts will be written separately, e.g.,
+//                     {{p1}, {p2}, ...};
+//                     otherwise will be grouped together at the second last
+//                     dimension, i.e.,
+//                     {p1, p2, ...}.
+//   prefix: declaration header for the entropy table
+static void optimize_entropy_table(aom_count_type *counts,
+                                   FILE *const probsfile, int dim_of_cts,
+                                   int *cts_each_dim,
+                                   const aom_tree_index *tree,
+                                   int flatten_last_dim, char *prefix) {
+  aom_count_type *ct_ptr = counts;
+
+  assert(!flatten_last_dim || cts_each_dim[dim_of_cts - 1] == 2);
+
+  fprintf(probsfile, "%s = {\n", prefix);
+  if (parse_stats(&ct_ptr, probsfile, 1, dim_of_cts, cts_each_dim, tree,
+                  flatten_last_dim)) {
+    fprintf(probsfile, "Optimizer failed!\n");
+  }
+  fprintf(probsfile, "};\n\n");
+  fprintf(logfile, "\n");
+}
+
+int main(int argc, const char **argv) {
+  if (argc < 2) {
+    fprintf(stderr, "Please specify the input stats file!\n");
+    exit(EXIT_FAILURE);
+  }
+
+  FILE *const statsfile = fopen(argv[1], "rb");
+  if (statsfile == NULL) {
+    fprintf(stderr, "Failed to open input file!\n");
+    exit(EXIT_FAILURE);
+  }
+
+  FRAME_COUNTS fc;
+  fread(&fc, sizeof(FRAME_COUNTS), 1, statsfile);
+
+  FILE *const probsfile = fopen("optimized_probs.c", "w");
+  if (probsfile == NULL) {
+    fprintf(stderr,
+            "Failed to create output file for optimized entropy tables!\n");
+    exit(EXIT_FAILURE);
+  }
+
+  logfile = fopen("aom_entropy_optimizer_parsed_counts.log", "w");
+  if (logfile == NULL) {
+    fprintf(stderr, "Failed to create log file for parsed counts!\n");
+    exit(EXIT_FAILURE);
+  }
+
+  int cts_each_dim[10];
+
+  /* Intra mode (keyframe luma) */
+  cts_each_dim[0] = INTRA_MODES;
+  cts_each_dim[1] = INTRA_MODES;
+  cts_each_dim[2] = INTRA_MODES;
+  optimize_entropy_table(
+      &(fc.kf_y_mode[0][0][0]), probsfile, 3, cts_each_dim, av1_intra_mode_tree,
+      0,
+      "const aom_prob av1_kf_y_mode_prob[INTRA_MODES][INTRA_MODES]"
+      "[INTRA_MODES - 1]");
+
+  /* Intra mode (non-keyframe luma) */
+  cts_each_dim[0] = BLOCK_SIZE_GROUPS;
+  cts_each_dim[1] = INTRA_MODES;
+  optimize_entropy_table(
+      &(fc.y_mode[0][0]), probsfile, 2, cts_each_dim, av1_intra_mode_tree, 0,
+      "static const aom_prob default_if_y_probs[BLOCK_SIZE_GROUPS]"
+      "[INTRA_MODES - 1]");
+
+  /* Intra mode (chroma) */
+  cts_each_dim[0] = INTRA_MODES;
+  cts_each_dim[1] = INTRA_MODES;
+  optimize_entropy_table(&(fc.uv_mode[0][0]), probsfile, 2, cts_each_dim,
+                         av1_intra_mode_tree, 0,
+                         "static const aom_prob default_uv_probs[INTRA_MODES]"
+                         "[INTRA_MODES - 1]");
+
+  /* Partition */
+  cts_each_dim[0] = PARTITION_CONTEXTS;
+#if CONFIG_EXT_PARTITION_TYPES
+  cts_each_dim[1] = EXT_PARTITION_TYPES;
+  // TODO(yuec): Wrong prob for context = 0, because the old tree is used
+  optimize_entropy_table(&(fc.partition[0][0]), probsfile, 2, cts_each_dim,
+                         av1_ext_partition_tree, 0,
+                         "static const aom_prob default_partition_probs"
+                         "[PARTITION_CONTEXTS][EXT_PARTITION_TYPES - 1]");
+#else
+  cts_each_dim[1] = PARTITION_TYPES;
+  optimize_entropy_table(&(fc.partition[0][0]), probsfile, 2, cts_each_dim,
+                         av1_partition_tree, 0,
+                         "static const aom_prob default_partition_probs"
+                         "[PARTITION_CONTEXTS][PARTITION_TYPES - 1]");
+#endif
+
+  /* Interpolation filter */
+  cts_each_dim[0] = SWITCHABLE_FILTER_CONTEXTS;
+  cts_each_dim[1] = SWITCHABLE_FILTERS;
+  optimize_entropy_table(
+      &(fc.switchable_interp[0][0]), probsfile, 2, cts_each_dim,
+      av1_switchable_interp_tree, 0,
+      "static const aom_prob \n"
+      "default_switchable_interp_prob[SWITCHABLE_FILTER_CONTEXTS]"
+      "[SWITCHABLE_FILTERS - 1]");
+
+  /* Blockzero */
+  cts_each_dim[0] = TX_SIZES;
+  cts_each_dim[1] = PLANE_TYPES;
+  cts_each_dim[2] = REF_TYPES;
+  cts_each_dim[3] = BLOCKZ_CONTEXTS;
+  cts_each_dim[4] = 2;
+  optimize_entropy_table(
+      &(fc.blockz_count[0][0][0][0][0]), probsfile, 5, cts_each_dim, NULL, 1,
+      "static const aom_prob av1_default_blockzero_probs[TX_SIZES]"
+      "[PLANE_TYPES][REF_TYPES][BLOCKZ_CONTEXTS]");
+
+  /* Motion vector referencing */
+  cts_each_dim[0] = NEWMV_MODE_CONTEXTS;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(
+      &(fc.newmv_mode[0][0]), probsfile, 2, cts_each_dim, NULL, 1,
+      "static const aom_prob default_newmv_prob[NEWMV_MODE_CONTEXTS]");
+
+  cts_each_dim[0] = ZEROMV_MODE_CONTEXTS;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(
+      &(fc.zeromv_mode[0][0]), probsfile, 2, cts_each_dim, NULL, 1,
+      "static const aom_prob default_zeromv_prob[ZEROMV_MODE_CONTEXTS]");
+
+  cts_each_dim[0] = REFMV_MODE_CONTEXTS;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(
+      &(fc.refmv_mode[0][0]), probsfile, 2, cts_each_dim, NULL, 1,
+      "static const aom_prob default_refmv_prob[REFMV_MODE_CONTEXTS]");
+
+  cts_each_dim[0] = DRL_MODE_CONTEXTS;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(
+      &(fc.drl_mode[0][0]), probsfile, 2, cts_each_dim, NULL, 1,
+      "static const aom_prob default_drl_prob[DRL_MODE_CONTEXTS]");
+
+/* ext_inter experiment */
+#if CONFIG_EXT_INTER
+  /* New compound mode */
+  cts_each_dim[0] = INTER_MODE_CONTEXTS;
+  cts_each_dim[1] = INTER_COMPOUND_MODES;
+  optimize_entropy_table(
+      &(fc.inter_compound_mode[0][0]), probsfile, 2, cts_each_dim,
+      av1_inter_compound_mode_tree, 0,
+      "static const aom_prob default_inter_compound_mode_probs\n"
+      "[INTER_MODE_CONTEXTS][INTER_COMPOUND_MODES - 1]");
+#if CONFIG_COMPOUND_SINGLEREF
+  /* Compound singleref mode */
+  cts_each_dim[0] = INTER_MODE_CONTEXTS;
+  cts_each_dim[1] = INTER_SINGLEREF_COMP_MODES;
+  optimize_entropy_table(
+      &(fc.inter_singleref_comp_mode[0][0]), probsfile, 2, cts_each_dim,
+      av1_inter_singleref_comp_mode_tree, 0,
+      "static const aom_prob default_inter_singleref_comp_mode_probs\n"
+      "[INTER_MODE_CONTEXTS][INTER_SINGLEREF_COMP_MODES - 1]");
+#endif
+#if CONFIG_INTERINTRA
+  /* Interintra */
+  cts_each_dim[0] = BLOCK_SIZE_GROUPS;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(
+      &(fc.interintra[0][0]), probsfile, 2, cts_each_dim, NULL, 1,
+      "static const aom_prob default_interintra_prob[BLOCK_SIZE_GROUPS]");
+
+  cts_each_dim[0] = BLOCK_SIZE_GROUPS;
+  cts_each_dim[1] = INTERINTRA_MODES;
+  optimize_entropy_table(
+      &(fc.interintra_mode[0][0]), probsfile, 2, cts_each_dim,
+      av1_interintra_mode_tree, 0,
+      "static const aom_prob "
+      "default_interintra_mode_prob[BLOCK_SIZE_GROUPS][INTERINTRA_MODES - 1]");
+
+  cts_each_dim[0] = BLOCK_SIZES;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(
+      &(fc.wedge_interintra[0][0]), probsfile, 2, cts_each_dim, NULL, 1,
+      "static const aom_prob default_wedge_interintra_prob[BLOCK_SIZES]");
+#endif
+  /* Compound type */
+  cts_each_dim[0] = BLOCK_SIZES;
+  cts_each_dim[1] = COMPOUND_TYPES;
+  optimize_entropy_table(&(fc.compound_interinter[0][0]), probsfile, 2,
+                         cts_each_dim, av1_compound_type_tree, 0,
+                         "static const aom_prob default_compound_type_probs"
+                         "[BLOCK_SIZES][COMPOUND_TYPES - 1]");
+#endif
+
+/* motion_var and warped_motion experiments */
+#if CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION
+  cts_each_dim[0] = BLOCK_SIZES;
+  cts_each_dim[1] = MOTION_MODES;
+  optimize_entropy_table(
+      &(fc.motion_mode[0][0]), probsfile, 2, cts_each_dim, av1_motion_mode_tree,
+      0,
+      "static const aom_prob default_motion_mode_prob[BLOCK_SIZES]"
+      "[MOTION_MODES - 1]");
+#if CONFIG_MOTION_VAR && CONFIG_WARPED_MOTION
+  cts_each_dim[0] = BLOCK_SIZES;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(
+      &(fc.obmc[0][0]), probsfile, 2, cts_each_dim, NULL, 1,
+      "static const aom_prob default_obmc_prob[BLOCK_SIZES]");
+#endif  // CONFIG_MOTION_VAR && CONFIG_WARPED_MOTION
+#endif  // CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION
+
+  /* Intra/inter flag */
+  cts_each_dim[0] = INTRA_INTER_CONTEXTS;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(&(fc.intra_inter[0][0]), probsfile, 2, cts_each_dim,
+                         NULL, 1,
+                         "static const aom_prob default_intra_inter_p"
+                         "[INTRA_INTER_CONTEXTS]");
+
+  /* Single/comp ref flag */
+  cts_each_dim[0] = COMP_INTER_CONTEXTS;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(&(fc.comp_inter[0][0]), probsfile, 2, cts_each_dim,
+                         NULL, 1,
+                         "static const aom_prob default_comp_inter_p"
+                         "[COMP_INTER_CONTEXTS]");
+
+/* ext_comp_refs experiment */
+#if CONFIG_EXT_COMP_REFS
+  cts_each_dim[0] = COMP_REF_TYPE_CONTEXTS;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(
+      &(fc.comp_ref_type[0][0]), probsfile, 2, cts_each_dim, NULL, 1,
+      "static const aom_prob default_comp_ref_type_p[COMP_REF_TYPE_CONTEXTS]");
+
+  cts_each_dim[0] = UNI_COMP_REF_CONTEXTS;
+  cts_each_dim[1] = UNIDIR_COMP_REFS - 1;
+  cts_each_dim[2] = 2;
+  optimize_entropy_table(
+      &(fc.uni_comp_ref[0][0][0]), probsfile, 3, cts_each_dim, NULL, 1,
+      "static const aom_prob\n"
+      "default_uni_comp_ref_p[UNI_COMP_REF_CONTEXTS][UNIDIR_COMP_REFS - 1]");
+#endif
+
+  /* Reference frame (single ref) */
+  cts_each_dim[0] = REF_CONTEXTS;
+  cts_each_dim[1] = SINGLE_REFS - 1;
+  cts_each_dim[2] = 2;
+  optimize_entropy_table(
+      &(fc.single_ref[0][0][0]), probsfile, 3, cts_each_dim, NULL, 1,
+      "static const aom_prob default_single_ref_p[REF_CONTEXTS]"
+      "[SINGLE_REFS - 1]");
+
+#if CONFIG_EXT_REFS
+  /* ext_refs experiment */
+  cts_each_dim[0] = REF_CONTEXTS;
+  cts_each_dim[1] = FWD_REFS - 1;
+  cts_each_dim[2] = 2;
+  optimize_entropy_table(
+      &(fc.comp_ref[0][0][0]), probsfile, 3, cts_each_dim, NULL, 1,
+      "static const aom_prob default_comp_ref_p[REF_CONTEXTS][FWD_REFS - 1]");
+
+  cts_each_dim[0] = REF_CONTEXTS;
+  cts_each_dim[1] = BWD_REFS - 1;
+  cts_each_dim[2] = 2;
+  optimize_entropy_table(&(fc.comp_bwdref[0][0][0]), probsfile, 3, cts_each_dim,
+                         NULL, 1,
+                         "static const aom_prob "
+                         "default_comp_bwdref_p[REF_CONTEXTS][BWD_REFS - 1]");
+#else
+  /* Reference frame (compound refs) */
+  cts_each_dim[0] = REF_CONTEXTS;
+  cts_each_dim[1] = COMP_REFS - 1;
+  cts_each_dim[2] = 2;
+  optimize_entropy_table(
+      &(fc.comp_ref[0][0][0]), probsfile, 3, cts_each_dim, NULL, 1,
+      "static const aom_prob default_comp_ref_p[REF_CONTEXTS]"
+      "[COMP_REFS - 1]");
+#endif  // CONFIG_EXT_REFS
+
+/* Compound single ref inter mode */
+#if CONFIG_EXT_INTER && CONFIG_COMPOUND_SINGLEREF
+  cts_each_dim[0] = COMP_INTER_MODE_CONTEXTS;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(&(fc.comp_inter_mode[0][0]), probsfile, 2,
+                         cts_each_dim, NULL, 1,
+                         "static const aom_prob "
+                         "default_comp_inter_mode_p[COMP_INTER_MODE_CONTEXTS]");
+#endif
+
+/* Transform size */
+// TODO(yuec): av1_tx_size_tree has variable sizes, so needs special handling
+#if CONFIG_EXT_TX && CONFIG_RECT_TX && CONFIG_RECT_TX_EXT
+  cts_each_dim[0] = 2;
+  optimize_entropy_table(&(fc.quarter_tx_size[0]), probsfile, 1, cts_each_dim,
+                         NULL, 1,
+                         "static const aom_prob default_quarter_tx_size_prob");
+#endif
+#if CONFIG_VAR_TX
+  cts_each_dim[0] = TXFM_PARTITION_CONTEXTS;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(
+      &(fc.txfm_partition[0][0]), probsfile, 2, cts_each_dim, NULL, 1,
+      "static const aom_prob "
+      "default_txfm_partition_probs[TXFM_PARTITION_CONTEXTS]");
+#endif
+
+  /* Skip flag */
+  cts_each_dim[0] = SKIP_CONTEXTS;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(
+      &(fc.skip[0][0]), probsfile, 2, cts_each_dim, NULL, 1,
+      "static const aom_prob default_skip_probs[SKIP_CONTEXTS]");
+
+/* intrabc experiment */
+#if CONFIG_INTRABC
+  cts_each_dim[0] = 2;
+  optimize_entropy_table(&(fc.intrabc[0]), probsfile, 1, cts_each_dim, NULL, 1,
+                         "INTRABC_PROB_DEFAULT");
+#endif
+
+/* delta_q experiment */
+#if CONFIG_DELTA_Q
+  cts_each_dim[0] = DELTA_Q_PROBS;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(
+      &(fc.delta_q[0][0]), probsfile, 2, cts_each_dim, NULL, 1,
+      "static const aom_prob default_delta_q_probs[DELTA_Q_PROBS]");
+#if CONFIG_EXT_DELTA_Q
+  cts_each_dim[0] = DELTA_LF_PROBS;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(
+      &(fc.delta_lf[0][0]), probsfile, 2, cts_each_dim, NULL, 1,
+      "static const aom_prob default_delta_lf_probs[DELTA_LF_PROBS]");
+#endif
+#endif
+
+/* Transform type */
+#if CONFIG_EXT_TX
+// TODO(yuec): different trees are used depending on selected ext tx set
+#else
+  // TODO(yuec): intra_ext_tx use different trees depending on the context
+  cts_each_dim[0] = EXT_TX_SIZES;
+  cts_each_dim[1] = TX_TYPES;
+  optimize_entropy_table(&(fc.inter_ext_tx[0][0]), probsfile, 2, cts_each_dim,
+                         av1_ext_tx_tree, 0,
+                         "static const aom_prob default_inter_ext_tx_prob"
+                         "[EXT_TX_SIZES][TX_TYPES - 1]");
+#endif
+
+/* supertx experiment */
+#if CONFIG_SUPERTX
+  cts_each_dim[0] = PARTITION_SUPERTX_CONTEXTS;
+  cts_each_dim[1] = TX_SIZES;
+  cts_each_dim[2] = 2;
+  optimize_entropy_table(
+      &(fc.supertx[0][0][0]), probsfile, 3, cts_each_dim, NULL, 1,
+      "static const aom_prob\n"
+      "default_supertx_prob[PARTITION_SUPERTX_CONTEXTS][TX_SIZES]");
+#endif
+
+/* ext_intra experiment */
+#if CONFIG_EXT_INTRA
+#if CONFIG_INTRA_INTERP
+  cts_each_dim[0] = INTRA_FILTERS + 1;
+  cts_each_dim[1] = INTRA_FILTERS;
+  optimize_entropy_table(
+      &(fc.intra_filter[0][0]), probsfile, 2, cts_each_dim,
+      av1_intra_filter_tree, 0,
+      "static const aom_prob\n"
+      "default_intra_filter_probs[INTRA_FILTERS + 1][INTRA_FILTERS - 1]");
+#endif
+#endif
+
+/* filter_intra experiment */
+#if CONFIG_FILTER_INTRA
+  cts_each_dim[0] = PLANE_TYPES;
+  cts_each_dim[1] = 2;
+  optimize_entropy_table(&(fc.filter_intra[0][0]), probsfile, 2, cts_each_dim,
+                         NULL, 1,
+                         "static const aom_prob default_filter_intra_probs[2]");
+#endif
+
+  fclose(statsfile);
+  fclose(logfile);
+  fclose(probsfile);
+
+  return 0;
+}