title: FFMPEG merging two videos (Concatenation)
body: <p>I have been trying to merge (concatenate) two mp4 videos with same height and width but some error occurs .
  The code is :</p>
  
  <pre><code>FFmpeg ffmpeg = FFmpeg.getInstance(EditVideoActivity.this);
              String list = generateList(new String[]{ActualVideoFile.getAbsolutePath(), path});
              try {
                  ffmpeg.execute("ffmpeg -f concat -i " + list + " -c:v copy " + mergedVideo.getAbsolutePath(), new FFmpegExecuteResponseHandler() {
                      @Override
                      public void onStart() {
                          Log.e("Start", "Start");
                      }
  
                      @Override
                      public void onFinish() {
                          Log.e("FINISHED", "finish");
                      }
  
  
                      @Override
                      public void onSuccess(String message) {
                          Log.e("SUCCESS", message);
                      }
  
                      @Override
                      public void onProgress(String message) {
                          Log.e("PROGRESSSS", message);
                      }
  
                      @Override
                      public void onFailure(String message) {
                          Log.e("FAILURE", message);
                      }
  
  
                  });
              } catch (FFmpegCommandAlreadyRunningException e) {
                  e.printStackTrace();
                  Log.e("FFMEG Exception", "" + e);
              }
  </code></pre>
  
  <p>Logcat:</p>
  
  <pre><code>/PROGRESSSS: ffmpeg version 0.11.1 Copyright (c) 2000-2012 the FFmpeg developers
  06-09 01:24:09.400 8512-8512/com.myApp E/PROGRESSSS:   built on Dec 22 2014 12:52:34 with gcc 4.6 20120106 (prerelease)
  06-09 01:24:09.400 8512-8512/com.myApp E/PROGRESSSS:   configuration: --arch=arm --cpu=cortex-a8 --target-os=linux --enable-runtime-cpudetect --prefix=/data/data/info.guardianproject.ffmpeg/app_opt --enable-pic --disable-shared --enable-static --cross-prefix=/home/n8fr8/dev/android/ndk/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86_64/bin/arm-linux-androideabi- --sysroot=/home/n8fr8/dev/android/ndk/platforms/android-16/arch-arm --extra-cflags='-I../x264 -mfloat-abi=softfp -mfpu=neon -fPIE -pie' --extra-ldflags='-L../x264 -fPIE -pie' --enable-version3 --enable-gpl --disable-doc --enable-yasm --enable-decoders --enable-encoders --enable-muxers --enable-demuxers --enable-parsers --enable-protocols --enable-filters --enable-avresample --enable-libfreetype --disable-indevs --enable-indev=lavfi --disable-outdevs --enable-hwaccels --enable-ffmpeg --disable-ffplay --disable-ffprobe --disable-ffserver --disable-network --enable-libx264 --enable-zlib
  06-09 01:24:09.400 8512-8512/com.myApp E/PROGRESSSS:   libavutil      51. 54.100 / 51. 54.100
  06-09 01:24:09.400 8512-8512/com.myApp E/PROGRESSSS:   libavcodec     54. 23.100 / 54. 23.100
  06-09 01:24:09.400 8512-8512/com.myApp E/PROGRESSSS:   libavformat    54.  6.100 / 54.  6.100
  06-09 01:24:09.400 8512-8512/com.myApp E/PROGRESSSS:   libavdevice    54.  0.100 / 54.  0.100
  06-09 01:24:09.400 8512-8512/com.myApp E/PROGRESSSS:   libavfilter     2. 77.100 /  2. 77.100
  06-09 01:24:09.400 8512-8512/com.myApp E/PROGRESSSS:   libswscale      2.  1.100 /  2.  1.100
  06-09 01:24:09.400 8512-8512/com.myApp E/PROGRESSSS:   libswresample   0. 15.100 /  0. 15.100
  06-09 01:24:09.400 8512-8512/com.myApp E/PROGRESSSS:   libpostproc    52.  0.100 / 52.  0.100
  06-09 01:24:09.400 8512-8512/com.myApp E/PROGRESSSS: [NULL @ 0x2aeef3b0] Unable to find a suitable output format for 'ffmpeg'
  06-09 01:24:09.400 8512-8512/com.myApp E/PROGRESSSS: ffmpeg: Invalid argument
  06-09 01:24:09.400 8512-8512/com.myApp E/FAILURE: ffmpeg version 0.11.1 Copyright (c) 2000-2012 the FFmpeg developers
                                                          built on Dec 22 2014 12:52:34 with gcc 4.6 20120106 (prerelease)
                                                          configuration: --arch=arm --cpu=cortex-a8 --target-os=linux --enable-runtime-cpudetect --prefix=/data/data/info.guardianproject.ffmpeg/app_opt --enable-pic --disable-shared --enable-static --cross-prefix=/home/n8fr8/dev/android/ndk/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86_64/bin/arm-linux-androideabi- --sysroot=/home/n8fr8/dev/android/ndk/platforms/android-16/arch-arm --extra-cflags='-I../x264 -mfloat-abi=softfp -mfpu=neon -fPIE -pie' --extra-ldflags='-L../x264 -fPIE -pie' --enable-version3 --enable-gpl --disable-doc --enable-yasm --enable-decoders --enable-encoders --enable-muxers --enable-demuxers --enable-parsers --enable-protocols --enable-filters --enable-avresample --enable-libfreetype --disable-indevs --enable-indev=lavfi --disable-outdevs --enable-hwaccels --enable-ffmpeg --disable-ffplay --disable-ffprobe --disable-ffserver --disable-network --enable-libx264 --enable-zlib
                                                          libavutil      51. 54.100 / 51. 54.100
                                                          libavcodec     54. 23.100 / 54. 23.100
                                                          libavformat    54.  6.100 / 54.  6.100
                                                          libavdevice    54.  0.100 / 54.  0.100
                                                          libavfilter     2. 77.100 /  2. 77.100
                                                          libswscale      2.  1.100 /  2.  1.100
                                                          libswresample   0. 15.100 /  0. 15.100
                                                          libpostproc    52.  0.100 / 52.  0.100
                                                        [NULL @ 0x2aeef3b0] Unable to find a suitable output format for 'ffmpeg'
                                                        ffmpeg: Invalid argument
  </code></pre>
  
  <p>I am using hiteshsondhi88 's FFMPEG Library 
  Any help would be appreciated.
  Thanks</p>