diff --git a/docs/using_cmake_build.txt b/docs/using_cmake_build.txt
new file mode 100644
index 00000000..67077d27
--- /dev/null
+++ b/docs/using_cmake_build.txt
@@ -0,0 +1,28 @@
+For building ccextractor using cmake folllow below steps..
+
+Step 1) Check you have right version of cmake installed. ( version >= 3.0.2 )
+	We are using CMP0037 policy of cmake which was introduced in 3.0.0
+	since we have tested our system only with cmake version 3.0.2, I would
+	suggest to use 3.0.2 or higher version.
+
+
+Step 2) create a seprate directory where you want to build the target.
+	In Unix you can do it using follwing commands.
+	~> cd ccextractor
+	~> mkdir build
+
+Step 3) make the build sytem using cmake
+	~> cmake ../src/
+
+Step 4) Compile the code.
+	~> make
+	~> make install
+
+Step 5) Use CCextractor as you would like
+
+
+If you want to build CCExtractor with FFMpeg you need to pass
+cmake -DWITH_FFMPEG=ON ../src/
+
+Hint for looking all the things you want to set from outside
+cmake -LAH ../src/
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 229f22ba..f0093143 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -2,6 +2,7 @@ cmake_minimum_required (VERSION 3.0.2)
 
 project (CCExtractor)
 
+option(WITH_FFMPEG "Build using FFmpeg demuxer and decoder" OFF)
 #Version number
 set (CCEXTRACTOR_VERSION_MAJOR 0)
 set (CCEXTRACTOR_VERSION_MINOR 75)
@@ -13,6 +14,7 @@ configure_file (
   "${PROJECT_BINARY_DIR}/CCExtractorConfig.h"
   )
 
+
 include_directories ("${PROJECT_SOURCE_DIR}")
 include_directories ("${PROJECT_SOURCE_DIR}/lib_ccx")
 include_directories ("${PROJECT_SOURCE_DIR}/gpacmp4/")
@@ -22,7 +24,7 @@ include_directories ("${PROJECT_SOURCE_DIR}/libccx_common/")
 LINK_DIRECTORIES(/opt/local/lib)
 LINK_DIRECTORIES(/usr/local/lib)
 
-SET (CMAKE_C_FLAGS "-O0 -Wall -g -std=gnu99 -Wno-write-strings -D_FILE_OFFSET_BITS=64")
+SET (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -O0 -Wall -g -std=gnu99 -Wno-write-strings -D_FILE_OFFSET_BITS=64")
 add_subdirectory (lib_ccx)
 
 AUX_SOURCE_DIRECTORY(${PROJECT_SOURCE_DIR} SOURCEFILE)
@@ -30,6 +32,22 @@ set (EXTRA_LIBS ${EXTRA_LIBS} ccx)
 set (EXTRA_LIBS ${EXTRA_LIBS} png)
 set (EXTRA_LIBS ${EXTRA_LIBS} m)
 
+########################################################
+# Build using FFmpeg libraries
+#
+if (WITH_FFMPEG)
+
+find_package(PkgConfig)
+pkg_check_modules(AVFORMAT REQUIRED libavformat)
+pkg_check_modules(AVUTIL REQUIRED libavutil)
+pkg_check_modules(AVCODEC REQUIRED libavcodec)
+set (EXTRA_LIBS ${EXTRA_LIBS} ${AVFORMAT_STATIC_LIBRARIES} )
+set (EXTRA_LIBS ${EXTRA_LIBS} ${AVUTIL_STATIC_LIBRARIES} )
+set (EXTRA_LIBS ${EXTRA_LIBS} ${AVCODEC_STATIC_LIBRARIES} )
+
+SET (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DENABLE_FFMPEG")
+endif (WITH_FFMPEG)
+
 add_executable(ccextractor ${SOURCEFILE})
 target_link_libraries (ccextractor ${EXTRA_LIBS})
 
diff --git a/src/ccextractor.c b/src/ccextractor.c
index 2ce4f22a..b1e9cdb6 100644
--- a/src/ccextractor.c
+++ b/src/ccextractor.c
@@ -28,7 +28,9 @@ int main(int argc, char *argv[])
 	char *c;
 	struct encoder_ctx enc_ctx[2];
 	struct cc_subtitle dec_sub;
+#ifdef ENABLE_FFMPEG
 	void *ffmpeg_ctx = NULL;
+#endif
 	struct lib_ccx_ctx *ctx;
 	struct lib_cc_decode *dec_ctx = NULL;
 
@@ -416,20 +418,12 @@ int main(int argc, char *argv[])
 		ffmpeg_ctx =  init_ffmpeg(ctx->inputfile[0]);
 		if(ffmpeg_ctx)
 		{
-			int i =0;
-			ctx->buffer = malloc(1024);
-			if(!ctx->buffer)
-			{
-				mprint("no memory left\n");
-				break;
-			}
 			do
 			{
 				int ret = 0;
-				char *bptr = ctx->buffer;
+				unsigned char *bptr = ctx->buffer;
 				int len = ff_get_ccframe(ffmpeg_ctx, bptr, 1024);
                                 int cc_count = 0;
-				memset(bptr,0,1024);
 				if(len == AVERROR(EAGAIN))
 				{
 					continue;
@@ -446,15 +440,13 @@ int main(int argc, char *argv[])
 				}
                                 else
                                     cc_count = len/3;
-				store_hdcc(ctx, bptr, cc_count, i++,fts_now,&dec_sub);
-				if(dec_sub.got_output)
+				ret = process_cc_data(dec_ctx, bptr, cc_count, &dec_sub);
+				if(ret >= 0 && dec_sub.got_output)
 				{
 					encode_sub(enc_ctx, &dec_sub);
 					dec_sub.got_output = 0;
 				}
 			}while(1);
-
-			free(ctx->buffer);
 			continue;
 		}
 		else
@@ -462,7 +454,6 @@ int main(int argc, char *argv[])
 			mprint ("\rFailed to initialized ffmpeg falling back to legacy\n");
 		}
 #endif
-
 		if (ctx->auto_stream == CCX_SM_AUTODETECT)
 		{
 			detect_stream_type(ctx);
@@ -711,7 +702,7 @@ int main(int argc, char *argv[])
 		// and need to be written after the last file is processed.		
 		cb_field1 = 0; cb_field2 = 0; cb_708 = 0;
 		fts_now = 0;
-		fts_max = 0;		
+		fts_max = 0;
 	} // file loop
 	close_input_file(ctx);
 	
diff --git a/src/lib_ccx/CMakeLists.txt b/src/lib_ccx/CMakeLists.txt
index 475c7c70..3a36f53f 100644
--- a/src/lib_ccx/CMakeLists.txt
+++ b/src/lib_ccx/CMakeLists.txt
@@ -1,6 +1,11 @@
 cmake_policy(SET CMP0037 NEW)
 
 SET (CMAKE_C_FLAGS "-O0 -Wall -g -std=gnu99")
+
+if (WITH_FFMPEG)
+SET (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DENABLE_FFMPEG")
+endif (WITH_FFMPEG)
+
 AUX_SOURCE_DIRECTORY("${PROJECT_SOURCE_DIR}/lib_ccx/" SOURCEFILE)
 AUX_SOURCE_DIRECTORY("${PROJECT_SOURCE_DIR}/gpacmp4/" SOURCEFILE)
 #AUX_SOURCE_DIRECTORY("${PROJECT_SOURCE_DIR}/libpng/" SOURCEFILE)
diff --git a/src/lib_ccx/ccx_decoders_common.c b/src/lib_ccx/ccx_decoders_common.c
index 9c182667..8cd800a2 100644
--- a/src/lib_ccx/ccx_decoders_common.c
+++ b/src/lib_ccx/ccx_decoders_common.c
@@ -100,7 +100,7 @@ unsigned get_decoder_line_basic(unsigned char *buffer, int line_num, struct eia6
 
 int process_cc_data (struct lib_cc_decode *ctx, unsigned char *cc_data, int cc_count, struct cc_subtitle *sub)
 {
-	int ret = 0;
+	int ret = -1;
 	for (int j = 0; j < cc_count * 3; j = j + 3)
 	{
 		if (validate_cc_data_pair( cc_data + j ) )
diff --git a/src/lib_ccx/ffmpeg_intgr.c b/src/lib_ccx/ffmpeg_intgr.c
index 6fe5b14f..0a74ec9c 100644
--- a/src/lib_ccx/ffmpeg_intgr.c
+++ b/src/lib_ccx/ffmpeg_intgr.c
@@ -126,7 +126,7 @@ fail:
  * @param maxlen length of buffer, where data will be copied
  * @return number of bytes recieved as data
  */
-int ff_get_ccframe(void *arg,char*data,int maxlen)
+int ff_get_ccframe(void *arg, unsigned char*data, int maxlen)
 {
 	struct ffmpeg_ctx *ctx = arg;
 	int len = 0;
diff --git a/src/lib_ccx/ffmpeg_intgr.h b/src/lib_ccx/ffmpeg_intgr.h
index efc963d9..3d0bce0b 100644
--- a/src/lib_ccx/ffmpeg_intgr.h
+++ b/src/lib_ccx/ffmpeg_intgr.h
@@ -19,5 +19,5 @@ void *init_ffmpeg(char *path);
  * @param maxlen length of buffer, where data will be copied
  * @return number of bytes recieved as data
  */
-int ff_get_ccframe(void *arg,char*data,int maxlen);
+int ff_get_ccframe(void *arg, unsigned char*data, int maxlen);
 #endif
diff --git a/src/lib_ccx/ts_tables.c b/src/lib_ccx/ts_tables.c
index 451f1f51..23de753f 100644
--- a/src/lib_ccx/ts_tables.c
+++ b/src/lib_ccx/ts_tables.c
@@ -271,7 +271,7 @@ int parse_PMT (struct lib_ccx_ctx *ctx, unsigned char *buf, int len, int pos)
 #ifndef ENABLE_OCR
 				if(ccx_options.write_format != CCX_OF_SPUPNG )
 				{
-					mprint ("Please Compile with ENABLE_OCR flag \n");
+					mprint ("DVB subtitles detected, OCR subsystem not present. Use -out=spupng for graphic output\n");
 					continue;
 				}
 #endif