diff --git a/vpx_util/vpx_thread.h b/vpx_util/vpx_thread.h
index 2062abd..f554bbc 100644
--- a/vpx_util/vpx_thread.h
+++ b/vpx_util/vpx_thread.h
@@ -10,8 +10,7 @@
 // Multi-threaded worker
 //
 // Original source:
-//  http://git.chromium.org/webm/libwebp.git
-//  100644 blob 7bd451b124ae3b81596abfbcc823e3cb129d3a38  src/utils/thread.h
+//  https://chromium.googlesource.com/webm/libwebp
 
 #ifndef VPX_THREAD_H_
 #define VPX_THREAD_H_
@@ -34,11 +33,26 @@
 #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
@@ -47,16 +61,30 @@
 #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;
@@ -72,7 +100,11 @@
 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;
 }
 
@@ -98,15 +130,22 @@
 // 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);
@@ -116,11 +155,15 @@
     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_);
@@ -129,12 +172,16 @@
     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))
@@ -145,6 +192,7 @@
         WAIT_OBJECT_0);
   ok &= ReleaseSemaphore(condition->received_sem_, 1, NULL);
   pthread_mutex_lock(mutex);
+#endif
   return !ok;
 }
 #elif defined(__OS2__)