ffmpeg -i "concat:intermediate1.ts|intermediate2.ts" -c copy -bsf:a aac_adtstoasc output.mp4
ffmpeg version 2.6.3 Copyright (c) 2000-2015 the FFmpeg developers
  built with Apple LLVM version 6.1.0 (clang-602.0.53) (based on LLVM 3.6.0svn)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/2.6.3 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-libx264 --enable-libmp3lame --enable-libvo-aacenc --enable-libxvid --enable-vda
  libavutil      54. 20.100 / 54. 20.100
  libavcodec     56. 26.100 / 56. 26.100
  libavformat    56. 25.101 / 56. 25.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 11.102 /  5. 11.102
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
Input #0, mpegts, from 'concat:intermediate1.ts|intermediate2.ts':
  Duration: 00:00:03.07, start: 1.400000, bitrate: 37306 kb/s
  Program 1
    Metadata:
      service_name    : Service01
      service_provider: FFmpeg
    Stream #0:0[0x100]: Video: h264 (Baseline) ([27][0][0][0] / 0x001B), yuv420p, 1280x720, 30 tbr, 90k tbn, 180k tbc
    Stream #0:1[0x101](und): Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000 Hz, stereo, fltp, 259 kb/s
Output #0, mp4, to 'output.mp4':
  Metadata:
    encoder         : Lavf56.25.101
    Stream #0:0: Video: h264 ([33][0][0][0] / 0x0021), yuv420p, 1280x720, q=2-31, 30 tbr, 90k tbn, 90k tbc
    Stream #0:1(und): Audio: aac ([64][0][0][0] / 0x0040), 48000 Hz, stereo, 259 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
[mp4 @ 0x7ff1fb800000] Non-monotonous DTS in output stream 0:0; previous: 758527, current: 758527; changing to 758528. This may result in incorrect timestamps in the output file.
[mp4 @ 0x7ff1fb800000] Non-monotonous DTS in output stream 0:1; previous: 409952, current: 407274; changing to 409953. This may result in incorrect timestamps in the output file.
[mp4 @ 0x7ff1fb800000] Non-monotonous DTS in output stream 0:1; previous: 409953, current: 408298; changing to 409954. This may result in incorrect timestamps in the output file.
[mp4 @ 0x7ff1fb800000] Non-monotonous DTS in output stream 0:1; previous: 409954, current: 409322; changing to 409955. This may result in incorrect timestamps in the output file.
frame=  329 fps=0.0 q=-1.0 Lsize=   12944kB time=00:00:11.42 bitrate=9278.4kbits/s
video:12664kB audio:268kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.093747%