diff --git a/README.chromium b/README.chromium
index b507acaa5..a5e4c7638 100644
--- a/README.chromium
+++ b/README.chromium
@@ -1,6 +1,6 @@
 Name: libyuv
 URL: http://code.google.com/p/libyuv/
-Version: 271
+Version: 272
 License: BSD
 License File: LICENSE
 
diff --git a/include/libyuv/cpu_id.h b/include/libyuv/cpu_id.h
index 354919bdb..5638b29f8 100644
--- a/include/libyuv/cpu_id.h
+++ b/include/libyuv/cpu_id.h
@@ -17,19 +17,21 @@ extern "C" {
 #endif
 
 // Internal flag to indicate cpuid is initialized.
-static const int kCpuInitialized = 1;
+static const int kCpuInitialized = 0x1;
 
-// These flags are only valid on ARM processors
-static const int kCpuHasARM = 2;
-static const int kCpuHasNEON = 4;
+// These flags are only valid on ARM processors.
+static const int kCpuHasARM = 0x2;
+static const int kCpuHasNEON = 0x4;
+// 0x8 reserved for future ARM flag.
 
-// These flags are only valid on x86 processors
-static const int kCpuHasX86 = 8;
-static const int kCpuHasSSE2 = 16;
-static const int kCpuHasSSSE3 = 32;
-static const int kCpuHasSSE41 = 64;
-static const int kCpuHasSSE42 = 128;
-static const int kCpuHasAVX = 256;
+// These flags are only valid on x86 processors.
+static const int kCpuHasX86 = 0x10;
+static const int kCpuHasSSE2 = 0x20;
+static const int kCpuHasSSSE3 = 0x40;
+static const int kCpuHasSSE41 = 0x80;
+static const int kCpuHasSSE42 = 0x100;
+static const int kCpuHasAVX = 0x200;
+// 0x400 reserved for AVX2.
 
 // Detect CPU has SSE2 etc.
 // Test_flag parameter should be one of kCpuHas constants above.
diff --git a/include/libyuv/version.h b/include/libyuv/version.h
index d398bc2b8..a07cbb901 100644
--- a/include/libyuv/version.h
+++ b/include/libyuv/version.h
@@ -11,7 +11,7 @@
 #ifndef INCLUDE_LIBYUV_VERSION_H_
 #define INCLUDE_LIBYUV_VERSION_H_
 
-#define LIBYUV_VERSION 271
+#define LIBYUV_VERSION 272
 
 #endif  // INCLUDE_LIBYUV_VERSION_H_
 
diff --git a/source/cpu_id.cc b/source/cpu_id.cc
index 54bce3cc6..c451fa18b 100644
--- a/source/cpu_id.cc
+++ b/source/cpu_id.cc
@@ -104,6 +104,12 @@ int InitCpuFlags() {
   if (getenv("LIBYUV_DISABLE_SSE41")) {
     cpu_info_ &= ~kCpuHasSSE41;
   }
+  if (getenv("LIBYUV_DISABLE_SSE42")) {
+    cpu_info_ &= ~kCpuHasSSE42;
+  }
+  if (getenv("LIBYUV_DISABLE_AVX")) {
+    cpu_info_ &= ~kCpuHasAVX;
+  }
   if (getenv("LIBYUV_DISABLE_ASM")) {
     cpu_info_ = kCpuInitialized;
   }
diff --git a/unit_test/cpu_test.cc b/unit_test/cpu_test.cc
index 393c72b6a..835544ce2 100644
--- a/unit_test/cpu_test.cc
+++ b/unit_test/cpu_test.cc
@@ -26,21 +26,21 @@ TEST_F(libyuvTest, TestCpuHas) {
   int cpu_flags = TestCpuFlag(~kCpuInitialized);
   printf("Cpu Flags %x\n", cpu_flags);
   int has_arm = TestCpuFlag(kCpuHasARM);
-  printf("Has ARM %d\n", has_arm);
+  printf("Has ARM %x\n", has_arm);
   int has_neon = TestCpuFlag(kCpuHasNEON);
-  printf("Has NEON %d\n", has_neon);
+  printf("Has NEON %x\n", has_neon);
   int has_x86 = TestCpuFlag(kCpuHasX86);
-  printf("Has X86 %d\n", has_x86);
+  printf("Has X86 %x\n", has_x86);
   int has_sse2 = TestCpuFlag(kCpuHasSSE2);
-  printf("Has SSE2 %d\n", has_sse2);
+  printf("Has SSE2 %x\n", has_sse2);
   int has_ssse3 = TestCpuFlag(kCpuHasSSSE3);
-  printf("Has SSSE3 %d\n", has_ssse3);
+  printf("Has SSSE3 %x\n", has_ssse3);
   int has_sse41 = TestCpuFlag(kCpuHasSSE41);
-  printf("Has SSE4.1 %d\n", has_sse41);
+  printf("Has SSE4.1 %x\n", has_sse41);
   int has_sse42 = TestCpuFlag(kCpuHasSSE42);
-  printf("Has SSE4.2 %d\n", has_sse42);
+  printf("Has SSE4.2 %x\n", has_sse42);
   int has_avx = TestCpuFlag(kCpuHasAVX);
-  printf("Has AVX %d\n", has_avx);
+  printf("Has AVX %x\n", has_avx);
 }
 
 #if defined(__i386__) || defined(__x86_64__) || \
@@ -79,7 +79,8 @@ TEST_F(libyuvTest, TestCpuId) {
     CpuId(cpu_info, 1);
     int family = ((cpu_info[0] >> 8) & 0x0f) | ((cpu_info[0] >> 16) & 0xff0);
     int model = ((cpu_info[0] >> 4) & 0x0f) | ((cpu_info[0] >> 12) & 0xf0);
-    printf("Cpu Family %d, Model %d\n", family, model);
+    printf("Cpu Family %d (0x%x), Model %d (0x%x)\n", family, family,
+           model, model);
   }
 }
 #endif