diff --git a/atom.cpp b/atom.cpp
index 0ca8b97e..275f2dac 100644
--- a/atom.cpp
+++ b/atom.cpp
@@ -1,13 +1,9 @@
 #include "AP_AtomDefinitions.h"
 #include "atom.h"
-#include "file.h"
 
-#include <string>
 #include <map>
 #include <iostream>
-
-#include <assert.h>
-#include <endian.h>
+#include <cassert>
 
 using namespace std;
 
diff --git a/atom.h b/atom.h
index 0ea7bb5c..304d64c5 100644
--- a/atom.h
+++ b/atom.h
@@ -1,12 +1,12 @@
 #ifndef ATOM_H
 #define ATOM_H
-extern "C" {
-    #include <stdint.h>
-}
+
 #include <vector>
 #include <string>
+#include <cstdint>
 
 #include "file.h"
+
 class Atom {
 public:
     int64_t start;       //including 8 header bytes
diff --git a/file.cpp b/file.cpp
index 3b4310ea..8fd4d36c 100644
--- a/file.cpp
+++ b/file.cpp
@@ -19,8 +19,7 @@
                                                         */
 
 #include "file.h"
-#include <string>
-#include <endian.h>
+#include "endian.h"
 
 using namespace std;
 
diff --git a/file.h b/file.h
index edf1a3aa..087e65aa 100644
--- a/file.h
+++ b/file.h
@@ -21,12 +21,10 @@
 #ifndef FILE_H
 #define FILE_H
 
-extern "C" {
-	#include <stdint.h>
-}
-#include <stdio.h>
 #include <vector>
 #include <string>
+#include <cstdint>
+#include <cstdio>
 
 uint16_t swap16(uint16_t us);
 uint32_t swap32(uint32_t ui);
diff --git a/mp4.cpp b/mp4.cpp
index 42b7af0e..3ec2ebff 100644
--- a/mp4.cpp
+++ b/mp4.cpp
@@ -18,14 +18,22 @@
 
 														*/
 
-#include <assert.h>
-#include <string>
 #include <iostream>
+#include <cassert>
+
+#ifndef __STDC_LIMIT_MACROS
+# define __STDC_LIMIT_MACROS	1
+#endif
+#ifndef __STDC_CONSTANT_MACROS
+# define __STDC_CONSTANT_MACROS	1
+#endif
+#include <cstdint>
+#ifndef INT64_C
+# define INT64_C(c)	(c ## LL)
+# define UINT64_C(c)	(c ## ULL)
+#endif
 
-#define __STDC_LIMIT_MACROS 1
-#define __STDC_CONSTANT_MACROS 1
 extern "C" {
-#include <stdint.h>
 #include "libavcodec/avcodec.h"
 #include "libavformat/avformat.h"
 }
diff --git a/mp4.h b/mp4.h
index 0c9ee1a6..252f5a0f 100644
--- a/mp4.h
+++ b/mp4.h
@@ -23,9 +23,9 @@
 
 #include <vector>
 #include <string>
-#include <stdio.h>
 
 #include "track.h"
+
 class Atom;
 class File;
 class AVFormatContext;
diff --git a/track.cpp b/track.cpp
index ebdba20e..3bf08e46 100644
--- a/track.cpp
+++ b/track.cpp
@@ -18,51 +18,48 @@
 
 														*/
 
-#include "track.h"
-#include "atom.h"
-
 #include <iostream>
-#include <vector>
-#include <string.h>
-#include <assert.h>
-#include <endian.h>
+#include <cassert>
 
-#define __STDC_LIMIT_MACROS 1
-#define __STDC_CONSTANT_MACROS 1
-
-extern "C" {
+#ifndef __STDC_LIMIT_MACROS
+# define __STDC_LIMIT_MACROS    1
+#endif
+#ifndef __STDC_CONSTANT_MACROS
+# define __STDC_CONSTANT_MACROS 1
+#endif
+#include <cstdint>
 #ifndef INT64_C
-#define INT64_C(c) (c ## LL)
-#define UINT64_C(c) (c ## ULL)
+# define INT64_C(c)     (c ## LL)
+# define UINT64_C(c)    (c ## ULL)
 #endif
+#include <cstdbool> // Define C11 bool used in internal header included below.
 
-#include <stdint.h>
+extern "C" {
 #include <libavcodec/avcodec.h>
 #include <libavformat/avformat.h>
-#include <libavcodec/avcodec.h>
 
-//Horrible hack: there is a variabled named 'new' and 'class' inside!
-#if LIBAVCODEC_VERSION_MAJOR != 56 //ubuntu 16.04 version
-#include <config.h>
-#undef restrict
-//#define restrict __restrict__
+// WARNING: Including internal header!
+#if LIBAVCODEC_VERSION_MAJOR != 56  // Ubuntu 16.04 version.
+# include <config.h>
+#endif
+// XXX Horrible Hack: Suppress C99 keywords that are not in C++, like 'restrict' and '_Atomic'! XXX
+#undef restrict     // Harmless; don't restrict memory access.
 #define restrict
-#define new extern_new
-#define class extern_class
+#undef _Atomic      // Atomics are only included in headers, but never actually used in our code.
+#define _Atomic
+// XXX Horrible Hack: There are variables named 'new' and 'class' inside! XXX
+#define new     extern_new
+#define class   extern_class
 #include <libavcodec/h264dec.h>
-#undef new
 #undef class
+#undef new
+#undef _Atomic
 #undef restrict
+}
 
-#else
-define new extern_new
-#define class extern_class
-#include <libavcodec/h264dec.h>
-#undef new
-#undef class
-#endif
+#include "track.h"
+#include "atom.h"
 
-}
 
 using namespace std;