ffmpeg -i http://127.0.0.1:223/stream/teststream -filter_complex "[0:v][0:s:2]overlay" -acodec copy -vcodec libx264 output3.mp4
ffmpeg version N-53536-gc3c7a87-static http://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2016 the FFmpeg developers
  built with gcc 5.3.1 (Debian 5.3.1-11) 20160307
  configuration: --enable-gpl --enable-version3 --disable-shared --disable-debug --enable-runtime-cpudetect --enable-libmp3lame --enable-libx264 --enable-libx265 --enable-libwebp --enable-libspeex --enable-libvorbis --enable-libvpx --enable-libfreetype --enable-fontconfig --enable-libxvid --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvo-amrwbenc --enable-gray --enable-libopenjpeg --enable-libopus --enable-libass --enable-gnutls --enable-libvidstab --enable-libsoxr --enable-frei0r --enable-libfribidi --disable-indev=sndio --disable-outdev=sndio --enable-librtmp --enable-libmfx --cc=gcc
  libavutil      55. 19.100 / 55. 19.100
  libavcodec     57. 28.103 / 57. 28.103
  libavformat    57. 28.101 / 57. 28.101
  libavdevice    57.  0.101 / 57.  0.101
  libavfilter     6. 39.102 /  6. 39.102
  libswscale      4.  0.100 /  4.  0.100
  libswresample   2.  0.101 /  2.  0.101
  libpostproc    54.  0.100 / 54.  0.100
[mpeg2video @ 0x5a7d360] Invalid frame dimensions 0x0.
    Last message repeated 3 times
Input #0, mpegts, from 'http://127.0.0.1:223/stream/teststream':
Duration: N/A, start: 23814.461822, bitrate: N/A
  Program 1
    Stream #0:0[0xc27]: Video: mpeg2video (Main) ([2][0][0][0] / 0x0002), yuv420p(tv), 720x576 [SAR 64:45 DAR 16:9], max. 15000 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
    Stream #0:1[0xc28](eng): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 192 kb/s
    Stream #0:2[0xc29](fra): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 192 kb/s
    Stream #0:3[0xc2a](deu): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 192 kb/s
    Stream #0:4[0xc2b](ita): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 192 kb/s
    Stream #0:5[0xc2c](eng,fra,deu,ita): Subtitle: dvb_teletext ([6][0][0][0] / 0x0006)
Stream specifier ':s:2' in filtergraph description [0:v][0:s:2]overlay matches no streams.