Import aom library

This is the reference implementation for the Alliance for Open Media's av1 video code.

The commit used was 4d668d7feb1f8abd809d1bca0418570a7f142a36.

7 files changed, 914 insertions, 0 deletions

diff --git a/third_party/aom/aom_util/aom_thread.c b/third_party/aom/aom_util/aom_thread.c
new file mode 100644
index 000000000..954b8f99c
--- /dev/null
+++ b/third_party/aom/aom_util/aom_thread.c
@@ -0,0 +1,183 @@
+/*
+ * Copyright (c) 2016, 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.
+ */
+//
+// Multi-threaded worker
+//
+// Original source:
+//  https://chromium.googlesource.com/webm/libwebp
+
+#include <assert.h>
+#include <string.h>  // for memset()
+#include "./aom_thread.h"
+#include "aom_mem/aom_mem.h"
+
+#if CONFIG_MULTITHREAD
+
+struct AVxWorkerImpl {
+  pthread_mutex_t mutex_;
+  pthread_cond_t condition_;
+  pthread_t thread_;
+};
+
+//------------------------------------------------------------------------------
+
+static void execute(AVxWorker *const worker);  // Forward declaration.
+
+static THREADFN thread_loop(void *ptr) {
+  AVxWorker *const worker = (AVxWorker *)ptr;
+  int done = 0;
+  while (!done) {
+    pthread_mutex_lock(&worker->impl_->mutex_);
+    while (worker->status_ == OK) {  // wait in idling mode
+      pthread_cond_wait(&worker->impl_->condition_, &worker->impl_->mutex_);
+    }
+    if (worker->status_ == WORK) {
+      execute(worker);
+      worker->status_ = OK;
+    } else if (worker->status_ == NOT_OK) {  // finish the worker
+      done = 1;
+    }
+    // signal to the main thread that we're done (for sync())
+    pthread_cond_signal(&worker->impl_->condition_);
+    pthread_mutex_unlock(&worker->impl_->mutex_);
+  }
+  return THREAD_RETURN(NULL);  // Thread is finished
+}
+
+// main thread state control
+static void change_state(AVxWorker *const worker, AVxWorkerStatus new_status) {
+  // No-op when attempting to change state on a thread that didn't come up.
+  // Checking status_ without acquiring the lock first would result in a data
+  // race.
+  if (worker->impl_ == NULL) return;
+
+  pthread_mutex_lock(&worker->impl_->mutex_);
+  if (worker->status_ >= OK) {
+    // wait for the worker to finish
+    while (worker->status_ != OK) {
+      pthread_cond_wait(&worker->impl_->condition_, &worker->impl_->mutex_);
+    }
+    // assign new status and release the working thread if needed
+    if (new_status != OK) {
+      worker->status_ = new_status;
+      pthread_cond_signal(&worker->impl_->condition_);
+    }
+  }
+  pthread_mutex_unlock(&worker->impl_->mutex_);
+}
+
+#endif  // CONFIG_MULTITHREAD
+
+//------------------------------------------------------------------------------
+
+static void init(AVxWorker *const worker) {
+  memset(worker, 0, sizeof(*worker));
+  worker->status_ = NOT_OK;
+}
+
+static int sync(AVxWorker *const worker) {
+#if CONFIG_MULTITHREAD
+  change_state(worker, OK);
+#endif
+  assert(worker->status_ <= OK);
+  return !worker->had_error;
+}
+
+static int reset(AVxWorker *const worker) {
+  int ok = 1;
+  worker->had_error = 0;
+  if (worker->status_ < OK) {
+#if CONFIG_MULTITHREAD
+    worker->impl_ = (AVxWorkerImpl *)aom_calloc(1, sizeof(*worker->impl_));
+    if (worker->impl_ == NULL) {
+      return 0;
+    }
+    if (pthread_mutex_init(&worker->impl_->mutex_, NULL)) {
+      goto Error;
+    }
+    if (pthread_cond_init(&worker->impl_->condition_, NULL)) {
+      pthread_mutex_destroy(&worker->impl_->mutex_);
+      goto Error;
+    }
+    pthread_mutex_lock(&worker->impl_->mutex_);
+    ok = !pthread_create(&worker->impl_->thread_, NULL, thread_loop, worker);
+    if (ok) worker->status_ = OK;
+    pthread_mutex_unlock(&worker->impl_->mutex_);
+    if (!ok) {
+      pthread_mutex_destroy(&worker->impl_->mutex_);
+      pthread_cond_destroy(&worker->impl_->condition_);
+    Error:
+      aom_free(worker->impl_);
+      worker->impl_ = NULL;
+      return 0;
+    }
+#else
+    worker->status_ = OK;
+#endif
+  } else if (worker->status_ > OK) {
+    ok = sync(worker);
+  }
+  assert(!ok || (worker->status_ == OK));
+  return ok;
+}
+
+static void execute(AVxWorker *const worker) {
+  if (worker->hook != NULL) {
+    worker->had_error |= !worker->hook(worker->data1, worker->data2);
+  }
+}
+
+static void launch(AVxWorker *const worker) {
+#if CONFIG_MULTITHREAD
+  change_state(worker, WORK);
+#else
+  execute(worker);
+#endif
+}
+
+static void end(AVxWorker *const worker) {
+#if CONFIG_MULTITHREAD
+  if (worker->impl_ != NULL) {
+    change_state(worker, NOT_OK);
+    pthread_join(worker->impl_->thread_, NULL);
+    pthread_mutex_destroy(&worker->impl_->mutex_);
+    pthread_cond_destroy(&worker->impl_->condition_);
+    aom_free(worker->impl_);
+    worker->impl_ = NULL;
+  }
+#else
+  worker->status_ = NOT_OK;
+  assert(worker->impl_ == NULL);
+#endif
+  assert(worker->status_ == NOT_OK);
+}
+
+//------------------------------------------------------------------------------
+
+static AVxWorkerInterface g_worker_interface = { init,   reset,   sync,
+                                                 launch, execute, end };
+
+int aom_set_worker_interface(const AVxWorkerInterface *const winterface) {
+  if (winterface == NULL || winterface->init == NULL ||
+      winterface->reset == NULL || winterface->sync == NULL ||
+      winterface->launch == NULL || winterface->execute == NULL ||
+      winterface->end == NULL) {
+    return 0;
+  }
+  g_worker_interface = *winterface;
+  return 1;
+}
+
+const AVxWorkerInterface *aom_get_worker_interface(void) {
+  return &g_worker_interface;
+}
+
+//------------------------------------------------------------------------------
diff --git a/third_party/aom/aom_util/aom_thread.h b/third_party/aom/aom_util/aom_thread.h
new file mode 100644
index 000000000..0ae8f2f49
--- /dev/null
+++ b/third_party/aom/aom_util/aom_thread.h
@@ -0,0 +1,412 @@
+/*
+ * Copyright (c) 2016, 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.
+ */
+//
+// Multi-threaded worker
+//
+// Original source:
+//  https://chromium.googlesource.com/webm/libwebp
+
+#ifndef AOM_THREAD_H_
+#define AOM_THREAD_H_
+
+#include "./aom_config.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Set maximum decode threads to be 8 due to the limit of frame buffers
+// and not enough semaphores in the emulation layer on windows.
+#define MAX_DECODE_THREADS 8
+
+#if CONFIG_MULTITHREAD
+
+#if defined(_WIN32) && !HAVE_PTHREAD_H
+#include <errno.h>    // NOLINT
+#include <process.h>  // NOLINT
+#include <windows.h>  // NOLINT
+typedef HANDLE pthread_t;
+typedef CRITICAL_SECTION pthread_mutex_t;
+
+#if _WIN32_WINNT >= 0x0600  // Windows Vista / Server 2008 or greater
+#define USE_WINDOWS_CONDITION_VARIABLE
+typedef CONDITION_VARIABLE pthread_cond_t;
+#else
+typedef struct {
+  HANDLE waiting_sem_;
+  HANDLE received_sem_;
+  HANDLE signal_event_;
+} pthread_cond_t;
+#endif  // _WIN32_WINNT >= 0x600
+
+#ifndef WINAPI_FAMILY_PARTITION
+#define WINAPI_PARTITION_DESKTOP 1
+#define WINAPI_FAMILY_PARTITION(x) x
+#endif
+
+#if !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
+#define USE_CREATE_THREAD
+#endif
+
+//------------------------------------------------------------------------------
+// simplistic pthread emulation layer
+
+// _beginthreadex requires __stdcall
+#define THREADFN unsigned int __stdcall
+#define THREAD_RETURN(val) (unsigned int)((DWORD_PTR)val)
+
+#if _WIN32_WINNT >= 0x0501  // Windows XP or greater
+#define WaitForSingleObject(obj, timeout) \
+  WaitForSingleObjectEx(obj, timeout, FALSE /*bAlertable*/)
+#endif
+
+static INLINE int pthread_create(pthread_t *const thread, const void *attr,
+                                 unsigned int(__stdcall *start)(void *),
+                                 void *arg) {
+  (void)attr;
+#ifdef USE_CREATE_THREAD
+  *thread = CreateThread(NULL,          /* lpThreadAttributes */
+                         0,             /* dwStackSize */
+                         start, arg, 0, /* dwStackSize */
+                         NULL);         /* lpThreadId */
+#else
+  *thread = (pthread_t)_beginthreadex(NULL,          /* void *security */
+                                      0,             /* unsigned stack_size */
+                                      start, arg, 0, /* unsigned initflag */
+                                      NULL);         /* unsigned *thrdaddr */
+#endif
+  if (*thread == NULL) return 1;
+  SetThreadPriority(*thread, THREAD_PRIORITY_ABOVE_NORMAL);
+  return 0;
+}
+
+static INLINE int pthread_join(pthread_t thread, void **value_ptr) {
+  (void)value_ptr;
+  return (WaitForSingleObject(thread, INFINITE) != WAIT_OBJECT_0 ||
+          CloseHandle(thread) == 0);
+}
+
+// Mutex
+static INLINE int pthread_mutex_init(pthread_mutex_t *const mutex,
+                                     void *mutexattr) {
+  (void)mutexattr;
+#if _WIN32_WINNT >= 0x0600  // Windows Vista / Server 2008 or greater
+  InitializeCriticalSectionEx(mutex, 0 /*dwSpinCount*/, 0 /*Flags*/);
+#else
+  InitializeCriticalSection(mutex);
+#endif
+  return 0;
+}
+
+static INLINE int pthread_mutex_trylock(pthread_mutex_t *const mutex) {
+  return TryEnterCriticalSection(mutex) ? 0 : EBUSY;
+}
+
+static INLINE int pthread_mutex_lock(pthread_mutex_t *const mutex) {
+  EnterCriticalSection(mutex);
+  return 0;
+}
+
+static INLINE int pthread_mutex_unlock(pthread_mutex_t *const mutex) {
+  LeaveCriticalSection(mutex);
+  return 0;
+}
+
+static INLINE int pthread_mutex_destroy(pthread_mutex_t *const mutex) {
+  DeleteCriticalSection(mutex);
+  return 0;
+}
+
+// Condition
+static INLINE int pthread_cond_destroy(pthread_cond_t *const condition) {
+  int ok = 1;
+#ifdef USE_WINDOWS_CONDITION_VARIABLE
+  (void)condition;
+#else
+  ok &= (CloseHandle(condition->waiting_sem_) != 0);
+  ok &= (CloseHandle(condition->received_sem_) != 0);
+  ok &= (CloseHandle(condition->signal_event_) != 0);
+#endif
+  return !ok;
+}
+
+static INLINE int pthread_cond_init(pthread_cond_t *const condition,
+                                    void *cond_attr) {
+  (void)cond_attr;
+#ifdef USE_WINDOWS_CONDITION_VARIABLE
+  InitializeConditionVariable(condition);
+#else
+  condition->waiting_sem_ = CreateSemaphore(NULL, 0, MAX_DECODE_THREADS, NULL);
+  condition->received_sem_ = CreateSemaphore(NULL, 0, MAX_DECODE_THREADS, NULL);
+  condition->signal_event_ = CreateEvent(NULL, FALSE, FALSE, NULL);
+  if (condition->waiting_sem_ == NULL || condition->received_sem_ == NULL ||
+      condition->signal_event_ == NULL) {
+    pthread_cond_destroy(condition);
+    return 1;
+  }
+#endif
+  return 0;
+}
+
+static INLINE int pthread_cond_signal(pthread_cond_t *const condition) {
+  int ok = 1;
+#ifdef USE_WINDOWS_CONDITION_VARIABLE
+  WakeConditionVariable(condition);
+#else
+  if (WaitForSingleObject(condition->waiting_sem_, 0) == WAIT_OBJECT_0) {
+    // a thread is waiting in pthread_cond_wait: allow it to be notified
+    ok = SetEvent(condition->signal_event_);
+    // wait until the event is consumed so the signaler cannot consume
+    // the event via its own pthread_cond_wait.
+    ok &= (WaitForSingleObject(condition->received_sem_, INFINITE) !=
+           WAIT_OBJECT_0);
+  }
+#endif
+  return !ok;
+}
+
+static INLINE int pthread_cond_wait(pthread_cond_t *const condition,
+                                    pthread_mutex_t *const mutex) {
+  int ok;
+#ifdef USE_WINDOWS_CONDITION_VARIABLE
+  ok = SleepConditionVariableCS(condition, mutex, INFINITE);
+#else
+  // note that there is a consumer available so the signal isn't dropped in
+  // pthread_cond_signal
+  if (!ReleaseSemaphore(condition->waiting_sem_, 1, NULL)) return 1;
+  // now unlock the mutex so pthread_cond_signal may be issued
+  pthread_mutex_unlock(mutex);
+  ok = (WaitForSingleObject(condition->signal_event_, INFINITE) ==
+        WAIT_OBJECT_0);
+  ok &= ReleaseSemaphore(condition->received_sem_, 1, NULL);
+  pthread_mutex_lock(mutex);
+#endif
+  return !ok;
+}
+#elif defined(__OS2__)
+#define INCL_DOS
+#include <os2.h>  // NOLINT
+
+#include <errno.h>        // NOLINT
+#include <stdlib.h>       // NOLINT
+#include <sys/builtin.h>  // NOLINT
+
+#define pthread_t TID
+#define pthread_mutex_t HMTX
+
+typedef struct {
+  HEV event_sem_;
+  HEV ack_sem_;
+  volatile unsigned wait_count_;
+} pthread_cond_t;
+
+//------------------------------------------------------------------------------
+// simplistic pthread emulation layer
+
+#define THREADFN void *
+#define THREAD_RETURN(val) (val)
+
+typedef struct {
+  void *(*start_)(void *);
+  void *arg_;
+} thread_arg;
+
+static void thread_start(void *arg) {
+  thread_arg targ = *(thread_arg *)arg;
+  free(arg);
+
+  targ.start_(targ.arg_);
+}
+
+static INLINE int pthread_create(pthread_t *const thread, const void *attr,
+                                 void *(*start)(void *), void *arg) {
+  int tid;
+  thread_arg *targ = (thread_arg *)malloc(sizeof(*targ));
+  if (targ == NULL) return 1;
+
+  (void)attr;
+
+  targ->start_ = start;
+  targ->arg_ = arg;
+  tid = (pthread_t)_beginthread(thread_start, NULL, 1024 * 1024, targ);
+  if (tid == -1) {
+    free(targ);
+    return 1;
+  }
+
+  *thread = tid;
+  return 0;
+}
+
+static INLINE int pthread_join(pthread_t thread, void **value_ptr) {
+  (void)value_ptr;
+  return DosWaitThread(&thread, DCWW_WAIT) != 0;
+}
+
+// Mutex
+static INLINE int pthread_mutex_init(pthread_mutex_t *const mutex,
+                                     void *mutexattr) {
+  (void)mutexattr;
+  return DosCreateMutexSem(NULL, mutex, 0, FALSE) != 0;
+}
+
+static INLINE int pthread_mutex_trylock(pthread_mutex_t *const mutex) {
+  return DosRequestMutexSem(*mutex, SEM_IMMEDIATE_RETURN) == 0 ? 0 : EBUSY;
+}
+
+static INLINE int pthread_mutex_lock(pthread_mutex_t *const mutex) {
+  return DosRequestMutexSem(*mutex, SEM_INDEFINITE_WAIT) != 0;
+}
+
+static INLINE int pthread_mutex_unlock(pthread_mutex_t *const mutex) {
+  return DosReleaseMutexSem(*mutex) != 0;
+}
+
+static INLINE int pthread_mutex_destroy(pthread_mutex_t *const mutex) {
+  return DosCloseMutexSem(*mutex) != 0;
+}
+
+// Condition
+static INLINE int pthread_cond_destroy(pthread_cond_t *const condition) {
+  int ok = 1;
+  ok &= DosCloseEventSem(condition->event_sem_) == 0;
+  ok &= DosCloseEventSem(condition->ack_sem_) == 0;
+  return !ok;
+}
+
+static INLINE int pthread_cond_init(pthread_cond_t *const condition,
+                                    void *cond_attr) {
+  int ok = 1;
+  (void)cond_attr;
+
+  ok &=
+      DosCreateEventSem(NULL, &condition->event_sem_, DCE_POSTONE, FALSE) == 0;
+  ok &= DosCreateEventSem(NULL, &condition->ack_sem_, DCE_POSTONE, FALSE) == 0;
+  if (!ok) {
+    pthread_cond_destroy(condition);
+    return 1;
+  }
+  condition->wait_count_ = 0;
+  return 0;
+}
+
+static INLINE int pthread_cond_signal(pthread_cond_t *const condition) {
+  int ok = 1;
+
+  if (!__atomic_cmpxchg32(&condition->wait_count_, 0, 0)) {
+    ok &= DosPostEventSem(condition->event_sem_) == 0;
+    ok &= DosWaitEventSem(condition->ack_sem_, SEM_INDEFINITE_WAIT) == 0;
+  }
+
+  return !ok;
+}
+
+static INLINE int pthread_cond_broadcast(pthread_cond_t *const condition) {
+  int ok = 1;
+
+  while (!__atomic_cmpxchg32(&condition->wait_count_, 0, 0))
+    ok &= pthread_cond_signal(condition) == 0;
+
+  return !ok;
+}
+
+static INLINE int pthread_cond_wait(pthread_cond_t *const condition,
+                                    pthread_mutex_t *const mutex) {
+  int ok = 1;
+
+  __atomic_increment(&condition->wait_count_);
+
+  ok &= pthread_mutex_unlock(mutex) == 0;
+
+  ok &= DosWaitEventSem(condition->event_sem_, SEM_INDEFINITE_WAIT) == 0;
+
+  __atomic_decrement(&condition->wait_count_);
+
+  ok &= DosPostEventSem(condition->ack_sem_) == 0;
+
+  pthread_mutex_lock(mutex);
+
+  return !ok;
+}
+#else                 // _WIN32
+#include <pthread.h>  // NOLINT
+#define THREADFN void *
+#define THREAD_RETURN(val) val
+#endif
+
+#endif  // CONFIG_MULTITHREAD
+
+// State of the worker thread object
+typedef enum {
+  NOT_OK = 0,  // object is unusable
+  OK,          // ready to work
+  WORK         // busy finishing the current task
+} AVxWorkerStatus;
+
+// Function to be called by the worker thread. Takes two opaque pointers as
+// arguments (data1 and data2), and should return false in case of error.
+typedef int (*AVxWorkerHook)(void *, void *);
+
+// Platform-dependent implementation details for the worker.
+typedef struct AVxWorkerImpl AVxWorkerImpl;
+
+// Synchronization object used to launch job in the worker thread
+typedef struct {
+  AVxWorkerImpl *impl_;
+  AVxWorkerStatus status_;
+  AVxWorkerHook hook;  // hook to call
+  void *data1;         // first argument passed to 'hook'
+  void *data2;         // second argument passed to 'hook'
+  int had_error;       // return value of the last call to 'hook'
+} AVxWorker;
+
+// The interface for all thread-worker related functions. All these functions
+// must be implemented.
+typedef struct {
+  // Must be called first, before any other method.
+  void (*init)(AVxWorker *const worker);
+  // Must be called to initialize the object and spawn the thread. Re-entrant.
+  // Will potentially launch the thread. Returns false in case of error.
+  int (*reset)(AVxWorker *const worker);
+  // Makes sure the previous work is finished. Returns true if worker->had_error
+  // was not set and no error condition was triggered by the working thread.
+  int (*sync)(AVxWorker *const worker);
+  // Triggers the thread to call hook() with data1 and data2 arguments. These
+  // hook/data1/data2 values can be changed at any time before calling this
+  // function, but not be changed afterward until the next call to Sync().
+  void (*launch)(AVxWorker *const worker);
+  // This function is similar to launch() except that it calls the
+  // hook directly instead of using a thread. Convenient to bypass the thread
+  // mechanism while still using the AVxWorker structs. sync() must
+  // still be called afterward (for error reporting).
+  void (*execute)(AVxWorker *const worker);
+  // Kill the thread and terminate the object. To use the object again, one
+  // must call reset() again.
+  void (*end)(AVxWorker *const worker);
+} AVxWorkerInterface;
+
+// Install a new set of threading functions, overriding the defaults. This
+// should be done before any workers are started, i.e., before any encoding or
+// decoding takes place. The contents of the interface struct are copied, it
+// is safe to free the corresponding memory after this call. This function is
+// not thread-safe. Return false in case of invalid pointer or methods.
+int aom_set_worker_interface(const AVxWorkerInterface *const winterface);
+
+// Retrieve the currently set thread worker interface.
+const AVxWorkerInterface *aom_get_worker_interface(void);
+
+//------------------------------------------------------------------------------
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
+#endif  // AOM_THREAD_H_
diff --git a/third_party/aom/aom_util/aom_util.cmake b/third_party/aom/aom_util/aom_util.cmake
new file mode 100644
index 000000000..484d9d9a0
--- /dev/null
+++ b/third_party/aom/aom_util/aom_util.cmake
@@ -0,0 +1,29 @@
+##
+## 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.
+##
+set(AOM_UTIL_SOURCES
+    "${AOM_ROOT}/aom_util/aom_thread.c"
+    "${AOM_ROOT}/aom_util/aom_thread.h"
+    "${AOM_ROOT}/aom_util/endian_inl.h")
+
+if (CONFIG_BITSTREAM_DEBUG)
+  set(AOM_UTIL_SOURCES
+      ${AOM_UTIL_SOURCES}
+      "${AOM_ROOT}/aom_util/debug_util.c"
+      "${AOM_ROOT}/aom_util/debug_util.h")
+endif ()
+
+# Creates the aom_util build target and makes libaom depend on it. The libaom
+# target must exist before this function is called.
+function (setup_aom_util_targets)
+  add_library(aom_util OBJECT ${AOM_UTIL_SOURCES})
+  set(AOM_LIB_TARGETS ${AOM_LIB_TARGETS} aom_util PARENT_SCOPE)
+  target_sources(aom PUBLIC $<TARGET_OBJECTS:aom_util>)
+endfunction ()
diff --git a/third_party/aom/aom_util/aom_util.mk b/third_party/aom/aom_util/aom_util.mk
new file mode 100644
index 000000000..14b484a15
--- /dev/null
+++ b/third_party/aom/aom_util/aom_util.mk
@@ -0,0 +1,18 @@
+##
+## Copyright (c) 2016, Alliance for Open Media. All rights reserved
+##
+## This source code is subject to the terms of the BSD 2 Clause License and
+## the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
+## was not distributed with this source code in the LICENSE file, you can
+## obtain it at www.aomedia.org/license/software. If the Alliance for Open
+## Media Patent License 1.0 was not distributed with this source code in the
+## PATENTS file, you can obtain it at www.aomedia.org/license/patent.
+##
+
+
+UTIL_SRCS-yes += aom_util.mk
+UTIL_SRCS-yes += aom_thread.c
+UTIL_SRCS-yes += aom_thread.h
+UTIL_SRCS-$(CONFIG_BITSTREAM_DEBUG) += debug_util.c
+UTIL_SRCS-$(CONFIG_BITSTREAM_DEBUG) += debug_util.h
+UTIL_SRCS-yes += endian_inl.h
diff --git a/third_party/aom/aom_util/debug_util.c b/third_party/aom/aom_util/debug_util.c
new file mode 100644
index 000000000..071d66976
--- /dev/null
+++ b/third_party/aom/aom_util/debug_util.c
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2016, 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.
+ */
+
+#include <assert.h>
+#include <stdio.h>
+#include <string.h>
+#include "aom_util/debug_util.h"
+
+#define QUEUE_MAX_SIZE 2000000
+static int result_queue[QUEUE_MAX_SIZE];
+#if CONFIG_DAALA_EC
+static int nsymbs_queue[QUEUE_MAX_SIZE];
+static aom_cdf_prob cdf_queue[QUEUE_MAX_SIZE][16];
+#else
+static int prob_queue[QUEUE_MAX_SIZE];
+#endif
+
+static int queue_r = 0;
+static int queue_w = 0;
+static int queue_prev_w = -1;
+static int skip_r = 0;
+static int skip_w = 0;
+
+static int frame_idx_w = 0;
+
+static int frame_idx_r = 0;
+
+void bitstream_queue_set_frame_write(int frame_idx) { frame_idx_w = frame_idx; }
+
+int bitstream_queue_get_frame_write(void) { return frame_idx_w; }
+
+void bitstream_queue_set_frame_read(int frame_idx) { frame_idx_r = frame_idx; }
+
+int bitstream_queue_get_frame_read(void) { return frame_idx_r; }
+
+void bitstream_queue_set_skip_write(int skip) { skip_w = skip; }
+
+void bitstream_queue_set_skip_read(int skip) { skip_r = skip; }
+
+void bitstream_queue_record_write(void) { queue_prev_w = queue_w; }
+
+void bitstream_queue_reset_write(void) { queue_w = queue_prev_w; }
+
+int bitstream_queue_get_write(void) { return queue_w; }
+
+int bitstream_queue_get_read(void) { return queue_r; }
+
+void bitstream_queue_pop(int *result,
+#if CONFIG_DAALA_EC
+                         aom_cdf_prob *cdf, int *nsymbs) {
+#else
+                         int *prob) {
+#endif  // CONFIG_DAALA_EC
+  if (!skip_r) {
+    if (queue_w == queue_r) {
+      printf("buffer underflow queue_w %d queue_r %d\n", queue_w, queue_r);
+      assert(0);
+    }
+    *result = result_queue[queue_r];
+#if CONFIG_DAALA_EC
+    *nsymbs = nsymbs_queue[queue_r];
+    memcpy(cdf, cdf_queue[queue_r], *nsymbs * sizeof(*cdf));
+#else
+    *prob = prob_queue[queue_r];
+#endif  // CONFIG_DAALA_EC
+    queue_r = (queue_r + 1) % QUEUE_MAX_SIZE;
+  }
+}
+
+void bitstream_queue_push(int result,
+#if CONFIG_DAALA_EC
+                          const aom_cdf_prob *cdf, int nsymbs) {
+#else
+                          int prob) {
+#endif  // CONFIG_DAALA_EC
+  if (!skip_w) {
+    result_queue[queue_w] = result;
+#if CONFIG_DAALA_EC
+    nsymbs_queue[queue_w] = nsymbs;
+    memcpy(cdf_queue[queue_w], cdf, nsymbs * sizeof(*cdf));
+#else
+    prob_queue[queue_w] = prob;
+#endif  // CONFIG_DAALA_EC
+    queue_w = (queue_w + 1) % QUEUE_MAX_SIZE;
+    if (queue_w == queue_r) {
+      printf("buffer overflow queue_w %d queue_r %d\n", queue_w, queue_r);
+      assert(0);
+    }
+  }
+}
diff --git a/third_party/aom/aom_util/debug_util.h b/third_party/aom/aom_util/debug_util.h
new file mode 100644
index 000000000..2ed56ea22
--- /dev/null
+++ b/third_party/aom/aom_util/debug_util.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2016, 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.
+ */
+
+#ifndef AOM_UTIL_DEBUG_UTIL_H_
+#define AOM_UTIL_DEBUG_UTIL_H_
+
+#include "./aom_config.h"
+#if CONFIG_DAALA_EC
+#include "aom_dsp/prob.h"
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* This is a debug tool used to detect bitstream error. On encoder side, it
+ * pushes each bit and probability into a queue before the bit is written into
+ * the Arithmetic coder. On decoder side, whenever a bit is read out from the
+ * Arithmetic coder, it pops out the reference bit and probability from the
+ * queue as well. If the two results do not match, this debug tool will report
+ * an error.  This tool can be used to pin down the bitstream error precisely.
+ * By combining gdb's backtrace method, we can detect which module causes the
+ * bitstream error. */
+int bitstream_queue_get_write(void);
+int bitstream_queue_get_read(void);
+void bitstream_queue_record_write(void);
+void bitstream_queue_reset_write(void);
+#if CONFIG_DAALA_EC
+void bitstream_queue_pop(int *result, aom_cdf_prob *cdf, int *nsymbs);
+void bitstream_queue_push(int result, const aom_cdf_prob *cdf, int nsymbs);
+#else
+void bitstream_queue_pop(int *result, int *prob);
+void bitstream_queue_push(int result, int prob);
+#endif
+void bitstream_queue_set_skip_write(int skip);
+void bitstream_queue_set_skip_read(int skip);
+void bitstream_queue_set_frame_write(int frame_idx);
+int bitstream_queue_get_frame_write(void);
+void bitstream_queue_set_frame_read(int frame_idx);
+int bitstream_queue_get_frame_read(void);
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
+#endif  // AOM_UTIL_DEBUG_UTIL_H_
diff --git a/third_party/aom/aom_util/endian_inl.h b/third_party/aom/aom_util/endian_inl.h
new file mode 100644
index 000000000..17a238649
--- /dev/null
+++ b/third_party/aom/aom_util/endian_inl.h
@@ -0,0 +1,120 @@
+/*
+ * Copyright (c) 2016, 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.
+ */
+//
+// Endian related functions.
+
+#ifndef AOM_UTIL_ENDIAN_INL_H_
+#define AOM_UTIL_ENDIAN_INL_H_
+
+#include <stdlib.h>
+#include "./aom_config.h"
+#include "aom/aom_integer.h"
+
+#if defined(__GNUC__)
+#define LOCAL_GCC_VERSION ((__GNUC__ << 8) | __GNUC_MINOR__)
+#define LOCAL_GCC_PREREQ(maj, min) (LOCAL_GCC_VERSION >= (((maj) << 8) | (min)))
+#else
+#define LOCAL_GCC_VERSION 0
+#define LOCAL_GCC_PREREQ(maj, min) 0
+#endif
+
+// handle clang compatibility
+#ifndef __has_builtin
+#define __has_builtin(x) 0
+#endif
+
+// some endian fix (e.g.: mips-gcc doesn't define __BIG_ENDIAN__)
+#if !defined(WORDS_BIGENDIAN) &&                   \
+    (defined(__BIG_ENDIAN__) || defined(_M_PPC) || \
+     (defined(__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)))
+#define WORDS_BIGENDIAN
+#endif
+
+#if defined(WORDS_BIGENDIAN)
+#define HToLE32 BSwap32
+#define HToLE16 BSwap16
+#define HToBE64(x) (x)
+#define HToBE32(x) (x)
+#else
+#define HToLE32(x) (x)
+#define HToLE16(x) (x)
+#define HToBE64(X) BSwap64(X)
+#define HToBE32(X) BSwap32(X)
+#endif
+
+#if LOCAL_GCC_PREREQ(4, 8) || __has_builtin(__builtin_bswap16)
+#define HAVE_BUILTIN_BSWAP16
+#endif
+
+#if LOCAL_GCC_PREREQ(4, 3) || __has_builtin(__builtin_bswap32)
+#define HAVE_BUILTIN_BSWAP32
+#endif
+
+#if LOCAL_GCC_PREREQ(4, 3) || __has_builtin(__builtin_bswap64)
+#define HAVE_BUILTIN_BSWAP64
+#endif
+
+#if HAVE_MIPS32 && defined(__mips__) && !defined(__mips64) && \
+    defined(__mips_isa_rev) && (__mips_isa_rev >= 2) && (__mips_isa_rev < 6)
+#define AOM_USE_MIPS32_R2
+#endif
+
+static INLINE uint16_t BSwap16(uint16_t x) {
+#if defined(HAVE_BUILTIN_BSWAP16)
+  return __builtin_bswap16(x);
+#elif defined(_MSC_VER)
+  return _byteswap_ushort(x);
+#else
+  // gcc will recognize a 'rorw $8, ...' here:
+  return (x >> 8) | ((x & 0xff) << 8);
+#endif  // HAVE_BUILTIN_BSWAP16
+}
+
+static INLINE uint32_t BSwap32(uint32_t x) {
+#if defined(AOM_USE_MIPS32_R2)
+  uint32_t ret;
+  __asm__ volatile(
+      "wsbh   %[ret], %[x]          \n\t"
+      "rotr   %[ret], %[ret],  16   \n\t"
+      : [ret] "=r"(ret)
+      : [x] "r"(x));
+  return ret;
+#elif defined(HAVE_BUILTIN_BSWAP32)
+  return __builtin_bswap32(x);
+#elif defined(__i386__) || defined(__x86_64__)
+  uint32_t swapped_bytes;
+  __asm__ volatile("bswap %0" : "=r"(swapped_bytes) : "0"(x));
+  return swapped_bytes;
+#elif defined(_MSC_VER)
+  return (uint32_t)_byteswap_ulong(x);
+#else
+  return (x >> 24) | ((x >> 8) & 0xff00) | ((x << 8) & 0xff0000) | (x << 24);
+#endif  // HAVE_BUILTIN_BSWAP32
+}
+
+static INLINE uint64_t BSwap64(uint64_t x) {
+#if defined(HAVE_BUILTIN_BSWAP64)
+  return __builtin_bswap64(x);
+#elif defined(__x86_64__)
+  uint64_t swapped_bytes;
+  __asm__ volatile("bswapq %0" : "=r"(swapped_bytes) : "0"(x));
+  return swapped_bytes;
+#elif defined(_MSC_VER)
+  return (uint64_t)_byteswap_uint64(x);
+#else   // generic code for swapping 64-bit values (suggested by bdb@)
+  x = ((x & 0xffffffff00000000ull) >> 32) | ((x & 0x00000000ffffffffull) << 32);
+  x = ((x & 0xffff0000ffff0000ull) >> 16) | ((x & 0x0000ffff0000ffffull) << 16);
+  x = ((x & 0xff00ff00ff00ff00ull) >> 8) | ((x & 0x00ff00ff00ff00ffull) << 8);
+  return x;
+#endif  // HAVE_BUILTIN_BSWAP64
+}
+
+#endif  // AOM_UTIL_ENDIAN_INL_H_