[sdf] Add copyright notices.
diff --git a/src/sdf/ftbsdf.c b/src/sdf/ftbsdf.c
index 13dbd45..dd28c50 100644
--- a/src/sdf/ftbsdf.c
+++ b/src/sdf/ftbsdf.c
@@ -1,3 +1,22 @@
+/****************************************************************************
+ *
+ * ftbsdf.c
+ *
+ *   Signed Distance Field support for bitmap fonts (body only).
+ *
+ * Copyright (C) 2020 by
+ * David Turner, Robert Wilhelm, and Werner Lemberg.
+ *
+ * Written by Anuj Verma.
+ *
+ * This file is part of the FreeType project, and may only be used,
+ * modified, and distributed under the terms of the FreeType project
+ * license, LICENSE.TXT.  By continuing to use, modify, or distribute
+ * this file you indicate that you have read the license and
+ * understand and accept it fully.
+ *
+ */
+
 
 #include <freetype/internal/ftobjs.h>
 #include <freetype/internal/ftdebug.h>
@@ -1313,4 +1332,5 @@
     (FT_Raster_Done_Func)    bsdf_raster_done       /* raster_done     */
   )
 
+
 /* END */
diff --git a/src/sdf/ftsdf.c b/src/sdf/ftsdf.c
index 77794dd..ef3922a 100644
--- a/src/sdf/ftsdf.c
+++ b/src/sdf/ftsdf.c
@@ -1,3 +1,22 @@
+/****************************************************************************
+ *
+ * ftsdf.c
+ *
+ *   Signed Distance Field support for outline fonts (body).
+ *
+ * Copyright (C) 2020 by
+ * David Turner, Robert Wilhelm, and Werner Lemberg.
+ *
+ * Written by Anuj Verma.
+ *
+ * This file is part of the FreeType project, and may only be used,
+ * modified, and distributed under the terms of the FreeType project
+ * license, LICENSE.TXT.  By continuing to use, modify, or distribute
+ * this file you indicate that you have read the license and
+ * understand and accept it fully.
+ *
+ */
+
 
 #include <freetype/internal/ftobjs.h>
 #include <freetype/internal/ftdebug.h>
@@ -3969,4 +3988,5 @@
     (FT_Raster_Done_Func)    sdf_raster_done       /* raster_done     */
   )
 
+
 /* END */
diff --git a/src/sdf/ftsdf.h b/src/sdf/ftsdf.h
index a8e243d..a833844 100644
--- a/src/sdf/ftsdf.h
+++ b/src/sdf/ftsdf.h
@@ -1,3 +1,22 @@
+/****************************************************************************
+ *
+ * ftsdf.h
+ *
+ *   Signed Distance Field support (specification).
+ *
+ * Copyright (C) 2020 by
+ * David Turner, Robert Wilhelm, and Werner Lemberg.
+ *
+ * Written by Anuj Verma.
+ *
+ * This file is part of the FreeType project, and may only be used,
+ * modified, and distributed under the terms of the FreeType project
+ * license, LICENSE.TXT.  By continuing to use, modify, or distribute
+ * this file you indicate that you have read the license and
+ * understand and accept it fully.
+ *
+ */
+
 
 #ifndef FTSDF_H_
 #define FTSDF_H_
@@ -74,4 +93,5 @@
 
 #endif /* FTSDF_H_ */
 
+
 /* END */
diff --git a/src/sdf/ftsdfcommon.h b/src/sdf/ftsdfcommon.h
index 22ec1d1..57c3e97 100644
--- a/src/sdf/ftsdfcommon.h
+++ b/src/sdf/ftsdfcommon.h
@@ -1,3 +1,22 @@
+/****************************************************************************
+ *
+ * ftsdfcommon.h
+ *
+ *   Auxiliary data for Signed Distance Field support (specification only).
+ *
+ * Copyright (C) 2020 by
+ * David Turner, Robert Wilhelm, and Werner Lemberg.
+ *
+ * Written by Anuj Verma.
+ *
+ * This file is part of the FreeType project, and may only be used,
+ * modified, and distributed under the terms of the FreeType project
+ * license, LICENSE.TXT.  By continuing to use, modify, or distribute
+ * this file you indicate that you have read the license and
+ * understand and accept it fully.
+ *
+ */
+
 
   /****************************************************
    *
@@ -148,4 +167,5 @@
 
 #endif /* FTSDFCOMMON_H_ */
 
+
 /* END */
diff --git a/src/sdf/ftsdferrs.h b/src/sdf/ftsdferrs.h
index b9f412f..2eb44aa 100644
--- a/src/sdf/ftsdferrs.h
+++ b/src/sdf/ftsdferrs.h
@@ -1,3 +1,22 @@
+/****************************************************************************
+ *
+ * ftsdferrs.h
+ *
+ *   Signed Distance Field error codes (specification only).
+ *
+ * Copyright (C) 2020 by
+ * David Turner, Robert Wilhelm, and Werner Lemberg.
+ *
+ * Written by Anuj Verma.
+ *
+ * This file is part of the FreeType project, and may only be used,
+ * modified, and distributed under the terms of the FreeType project
+ * license, LICENSE.TXT.  By continuing to use, modify, or distribute
+ * this file you indicate that you have read the license and
+ * understand and accept it fully.
+ *
+ */
+
 
 #ifndef FTSDFERRS_H_
 #define FTSDFERRS_H_
@@ -14,4 +33,5 @@
 
 #endif /* FTSDFERRS_H_ */
 
+
 /* END */
diff --git a/src/sdf/ftsdfrend.c b/src/sdf/ftsdfrend.c
index 4870107..4f77909 100644
--- a/src/sdf/ftsdfrend.c
+++ b/src/sdf/ftsdfrend.c
@@ -1,3 +1,22 @@
+/****************************************************************************
+ *
+ * ftsdfrend.c
+ *
+ *   Signed Distance Field renderer interface (body).
+ *
+ * Copyright (C) 2020 by
+ * David Turner, Robert Wilhelm, and Werner Lemberg.
+ *
+ * Written by Anuj Verma.
+ *
+ * This file is part of the FreeType project, and may only be used,
+ * modified, and distributed under the terms of the FreeType project
+ * license, LICENSE.TXT.  By continuing to use, modify, or distribute
+ * this file you indicate that you have read the license and
+ * understand and accept it fully.
+ *
+ */
+
 
 #include <freetype/internal/ftdebug.h>
 #include <freetype/internal/ftobjs.h>
@@ -569,4 +588,5 @@
     (FT_Raster_Funcs*)&ft_bitmap_sdf_raster       /* raster_class    */
   )
 
+
 /* END */
diff --git a/src/sdf/ftsdfrend.h b/src/sdf/ftsdfrend.h
index 33e9338..506e2b6 100644
--- a/src/sdf/ftsdfrend.h
+++ b/src/sdf/ftsdfrend.h
@@ -1,3 +1,22 @@
+/****************************************************************************
+ *
+ * ftsdfrend.h
+ *
+ *   Signed Distance Field renderer interface (specification).
+ *
+ * Copyright (C) 2020 by
+ * David Turner, Robert Wilhelm, and Werner Lemberg.
+ *
+ * Written by Anuj Verma.
+ *
+ * This file is part of the FreeType project, and may only be used,
+ * modified, and distributed under the terms of the FreeType project
+ * license, LICENSE.TXT.  By continuing to use, modify, or distribute
+ * this file you indicate that you have read the license and
+ * understand and accept it fully.
+ *
+ */
+
 
 #ifndef FTSDFREND_H_
 #define FTSDFREND_H_
@@ -95,4 +114,5 @@
 
 #endif /* FTSDFREND_H_ */
 
+
 /* END */
diff --git a/src/sdf/sdf.c b/src/sdf/sdf.c
index 7867787..35e7c8b 100644
--- a/src/sdf/sdf.c
+++ b/src/sdf/sdf.c
@@ -1,3 +1,22 @@
+/****************************************************************************
+ *
+ * sdf.c
+ *
+ *   FreeType Signed Distance Field renderer module component (body only).
+ *
+ * Copyright (C) 2020 by
+ * David Turner, Robert Wilhelm, and Werner Lemberg.
+ *
+ * Written by Anuj Verma.
+ *
+ * This file is part of the FreeType project, and may only be used,
+ * modified, and distributed under the terms of the FreeType project
+ * license, LICENSE.TXT.  By continuing to use, modify, or distribute
+ * this file you indicate that you have read the license and
+ * understand and accept it fully.
+ *
+ */
+
 
 #define FT_MAKE_OPTION_SINGLE_OBJECT
 
@@ -5,4 +24,5 @@
 #include "ftbsdf.c"
 #include "ftsdf.c"
 
+
 /* END */