[FFmpeg-user] Trouble Concatenating Video: "Application provided invalid, non monotonically increasing dts"

[ianm at brick.net]

I would like to join video clips.  I'm using the latest 
Zeranoe 64-bit build on Windows 7.  I was able to hammer 
something out for successive .MTS clips (H.264 video, AC-3 
audio, in an MPEG-TS container) generated by an AVCHD 
camera, like so:

1) Transcode all clips to an identifical, approved format 
and identical codecs, with the same display size and 
whatnot: MPEG-1
2) Binary concatenation of all of the files into one file, 
concatenated.mpg
3) Reel out the streams in concatenated.mpg into a new 
container

Having read the FAQ 
(http://ffmpeg.org/faq.html#How-can-I-join-video-files_003f), 
I picked MPEG-1 for transcoding (Thanks, Carl, for letting 
me know that the container MPEG-1 System Format is the 
same as the container format MPEG-2 Program Stream, I was 
very confused) using the following command:

1) ffmpeg -i clip1.mts -y -fmpeg -codec:v mpeg1video -b:v 
4000k -minrate 4000k -maxrate 4000k -bufsize 1835k -r 20 
-s hd720 -aspect 16:9 -pix_fmt yuv420p -filter:v yadif 
-codec:a mp2 -b:a 256k -ar 32000 -ac 2 clip1.mpg

These look great.  Upon joining the resulting MPEG-1 files 
with:

2) copy /y /b clip1.mpg+clip2.mpg+clip3.mpg 
concatenated.mpg

the file appears to play in Windows Media Player but the 
duration is too short (about twenty-seven minutes), only 
half as long as it needs to be (fifty-five minutes). 
 Windows Explorer says the same, as does RealProducer 14. 
 FFProbe gives a duration of only nine minutes and change, 
with an unrealistically high bandwidth.  I decided to 
"smooth out" the files with:

3) ffmpeg -i concatenated.mpg -f mpeg -codec:v copy 
-codec:a copy -y fixed.mpg

The resulting fixed.mpg gives the correct duration in 
Windows Media Player, ffprobe, RealProducer 14, and 
whatnot.  The video processes as expected.    Good so far!

WHERE IT ALL GOES WRONG: If I try this process on wildly 
disparate clips from different sources, in different 
formats, etc. (such as wanting to add in a default 
copyright notice), upon the final step "ffmpeg -i 
concatenated.mpg -f mpeg -codec:v copy -codec:a copy -y 
fixed.mpg" I get ...

ffmpeg version N-39267-g4082198 Copyright (c) 2000-2012 
the FFmpeg developers
   built on Mar 25 2012 20:30:15 with gcc 4.6.2
   configuration: --disable-static --enable-shared 
--enable-gpl --enable-version3 --disable-w32threads 
--enable-runtime-cpudetect --enable-avisynth 
--enable-bzlib --enable-frei0r --enable-libopencore-amrnb 
--enable-libopencore-amrwb --enable-libfreetype 
--enable-libgsm --enable-libmp3lame --enable-libopenjpeg 
--enable-librtmp --enable-libschroedinger 
--enable-libspeex --enable-libtheora --enable-libvo-aacenc 
--enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx 
--enable-libx264 --enable-libxavs --enable-libxvid 
--enable-zlib
   libavutil      51. 44.100 / 51. 44.100
   libavcodec     54. 12.100 / 54. 12.100
   libavformat    54.  3.100 / 54.  3.100
   libavdevice    53.  4.100 / 53.  4.100
   libavfilter     2. 65.102 /  2. 65.102
   libswscale      2.  1.100 /  2.  1.100
   libswresample   0. 10.100 /  0. 10.100
   libpostproc    52.  0.100 / 52.  0.100
[mpeg @ 000000000050F3D0] max_analyze_duration 5000000 
reached at 5004000
Input #0, mpeg, from 
'L:\data\pipeline\intermediate\concatenated.mpg':
   Duration: 00:00:10.02, start: 0.985278, bitrate: 8688 
kb/s
     Stream #0:0[0x1e0]: Video: mpeg1video, yuv420p, 
1280x720 [SAR 1:1 DAR 16:9], 4000 kb/s, 23.98 fps, 23.98 
tbr, 90k tbn, 23.98 tbc
     Stream #0:1[0x1c0]: Audio: mp2, 32000 Hz, 2 channels, 
s16, 256 kb/s
Output #0, mpeg, to 
'L:\data\pipeline\intermediate\fixed.mpg':
   Metadata:
     encoder         : Lavf54.3.100
     Stream #0:0: Video: mpeg1video, yuv420p, 1280x720 
[SAR 1:1 DAR 16:9], q=2-31, 4000 kb/s, 23.98 fps, 90k tbn, 
23.98 tbc
     Stream #0:1: Audio: mp2, 32000 Hz, 2 channels, 256 
kb/s
Stream mapping:
   Stream #0:0 -> #0:0 (copy)
   Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
[mpeg @ 00000000006AAA90] Application provided invalid, 
non monotonically increasing dts to muxer in stream 1: 
900720 >=  900720
av_interleaved_write_frame(): Invalid argument

How do I get around this?  I thought the three-step 
process was the way to go, but evidently there are 
timestamp issues.

Thanks!