[FFmpeg-user] stream mapping seems to work, but doesn't

[sean darcy]

I've got a bunch of VOB's I want to concatenate. For most of the VOB's 
stream 0:0 is video and 0:1 audio, but for one VOB te streams are 
switched, so concat doesn't work.

I tried to use map to switch the streams in the one VOB, which seemed to 
work:

fmpeg -i  out2.VOB  -map 0:1 -map 0:0 -c copy out2-x.VOB
ffmpeg version 3.0.git Copyright (c) 2000-2016 the FFmpeg developers
   built with gcc 5.3.1 (GCC) 20151207 (Red Hat 5.3.1-2)
   configuration: --prefix=/usr --bindir=/usr/bin 
--datadir=/usr/share/ffmpeg --libdir=/usr/lib64 --mandir=/usr/share/man 
--shlibdir=/usr/lib64 --extra-cflags='-Ofast -march=native -fopenmp 
-mtune=native -fomit-frame-pointer -pipe' --extra-ldflags= 
--enable-static --enable-shared --enable-gray --enable-gpl 
--enable-nonfree --enable-version3 --enable-avdevice --enable-avcodec 
--enable-avformat --enable-avutil --enable-swresample --enable-swscale 
--enable-postproc --enable-avfilter --enable-avresample 
--enable-pthreads --enable-x11grab --enable-vdpau 
--enable-hardcoded-tables --enable-avisynth --enable-frei0r 
--enable-libfdk-aac --enable-libgsm --enable-libmp3lame 
--enable-libopencore-amrwb --enable-libopencv --enable-libopenjpeg 
--enable-libopus --enable-librtmp --enable-libschroedinger 
--enable-libsoxr --enable-libspeex --enable-libtheora 
--enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis 
--enable-libvpx --enable-libwebp --enable-libx264 --enable-libxvid 
--enable-zlib --disable-debug --cpu=amdfam10 --arch=x86_64 --enable-pic 
--enable-opengl --enable-openssl
   libavutil      55. 19.100 / 55. 19.100
   libavcodec     57. 31.100 / 57. 31.100
   libavformat    57. 29.101 / 57. 29.101
   libavdevice    57.  0.101 / 57.  0.101
   libavfilter     6. 40.102 /  6. 40.102
   libavresample   3.  0.  0 /  3.  0.  0
   libswscale      4.  0.100 /  4.  0.100
   libswresample   2.  0.101 /  2.  0.101
   libpostproc    54.  0.100 / 54.  0.100
[mpeg @ 0x8780e0] DTS discontinuity in stream 0: packet 3 with DTS 
50761, packet 4 with DTS 53641
Input #0, mpeg, from 'out2.VOB':
   Duration: 00:29:06.63, start: 0.500000, bitrate: 4892 kb/s
     Stream #0:0[0x80]: Audio: ac3, 48000 Hz, stereo, fltp, 224 kb/s
     Stream #0:1[0x1e0]: Video: mpeg2video (Main), yuv420p(tv, 
smpte170m), 720x480 [SAR 8:9 DAR 4:3], max. 8500 kb/s, 29.97 fps, 29.97 
tbr, 90k tbn, 59.94 tbc
[svcd @ 0x8804c0] VBV buffer size not set, using default size of 130KB
If you want the mpeg file to be compliant to some specification
Like DVD, VCD or others, make sure you set the correct buffer size
Output #0, svcd, to 'out2-x.VOB':
   Metadata:
     encoder         : Lavf57.29.101
     Stream #0:0: Video: mpeg2video, yuv420p, 720x480 [SAR 8:9 DAR 4:3], 
q=2-31, max. 8500 kb/s, 29.97 fps, 29.97 tbr, 90k tbn, 29.97 tbc
     Stream #0:1: Audio: ac3, 48000 Hz, stereo, 224 kb/s
Stream mapping:
   Stream #0:1 -> #0:0 (copy)
   Stream #0:0 -> #0:1 (copy)
Press [q] to stop, [?] for help
[svcd @ 0x8804c0] Timestamps are unset in a packet for stream 0. This is 
deprecated and will stop working in the future. Fix your code to set the 
timestamps properly
frame=52323 fps=3074 q=-1.0 Lsize= 1043146kB time=00:29:06.62 
bitrate=4892.6kbits/s speed= 103x
video:982531kB audio:47748kB subtitle:0kB other streams:0kB global 
headers:0kB muxing overhead: 1.248881%

BUT ffprobe shows it didn't happen:

ffprobe  out2-x.VOB
ffprobe version 3.0.git Copyright (c) 2007-2016 the FFmpeg developers
   built with gcc 5.3.1 (GCC) 20151207 (Red Hat 5.3.1-2)
   ...................................
[mpeg @ 0xfff780] DTS discontinuity in stream 0: packet 3 with DTS 
50761, packet 4 with DTS 53641
Input #0, mpeg, from 'out2-x.VOB':
   Duration: 00:29:06.63, start: 0.500000, bitrate: 4892 kb/s
     Stream #0:0[0x80]: Audio: ac3, 48000 Hz, stereo, fltp, 224 kb/s
     Stream #0:1[0x1e0]: Video: mpeg2video (Main), yuv420p(tv, 
smpte170m), 720x480 [SAR 8:9 DAR 4:3], max. 8500 kb/s, 29.97 fps, 29.97 
tbr, 90k tbn, 59.94 tbc

How can I switch these streams ??

sean