[FFmpeg-user] Mkv convert avi problem: Output file duration is not right:

[chenct1976 at sina.com]

Dear all,
I have met a problem when I convert a mkv file to avi.
Problem: input file duration is 25s, output file is 3'41s.  v0.8 is ok, but v0.10 is wrong.
OS        : MINGW32_NT-6.1 DEV-TOM 1.0.17(0.48/3/2) 2011-04-24 23:39 i686 Msys
Command line:  ./ffmpeg_g.exe -i intput1.mkv -vcodec mjpeg -b 2500000 -r 30 -s 640x480 -acodec pcm_s16le -ac 2 -ab 160000 -ar 44100 -y intput1.avi
Test input file link: http://www.mediafire.com/?bb1x23c4wzwff95
Test output log:
2012/03/19-11:16: ffmpeg version 0.10
2012/03/19-11:16: Copyright (c) 2000-2012 the FFmpeg developers
2012/03/19-11:16: built on Mar 19 2012 10:33:03 with gcc 4.5.2
2012/03/19-11:16: configuration: --prefix=/ffmpeg/release10 --enable-debug --disable-static --enable-shared --enable-gpl --enable-version3 --enable-avfilter --enable-memalign-hack --enable-avisynth --enable-libgsm --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libx264 --enable-libxvid --enable-libfaac --enable-nonfree --enable-libspeex --enable-libopenjpeg --enable-libxavs --enable-libvpx --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libschroedinger --enable-libcelt --enable-frei0r --enable-libdirac --disable-decoder=libdirac --extra-cflags=-I/ffmpeg/olibs9/include --extra-ldflags=-L/ffmpeg/olibs9/lib --extra-libs=/mingw/lib/libdl.a
2012/03/19-11:16: libavutil 51. 34.101 / 51. 34.101
2012/03/19-11:16: libavcodec 53. 60.100 / 53. 60.100
2012/03/19-11:16: libavformat 53. 31.100 / 53. 31.100
2012/03/19-11:16: libavdevice 53. 4.100 / 53. 4.100
2012/03/19-11:16: libavfilter 2. 60.100 / 2. 60.100
2012/03/19-11:16: libswscale 2. 1.100 / 2. 1.100
2012/03/19-11:16: libswresample 0. 6.100 / 0. 6.100
2012/03/19-11:16: libpostproc 52. 0.100 / 52. 0.100
2012/03/19-11:16: Input #0, matroska,webm, from 'intput1.mkv':
2012/03/19-11:16: Duration: 
2012/03/19-11:16: 00:00:25.39
2012/03/19-11:16: start: 
2012/03/19-11:16: 0.000000
2012/03/19-11:16: bitrate: 
2012/03/19-11:16: 966 kb/s
2012/03/19-11:16: Stream #0:0
2012/03/19-11:16: Video: h264 (Constrained Baseline), yuv420p, 640x480
2012/03/19-11:16: SAR 1:1 DAR 4:3
2012/03/19-11:16: 30 tbr
2012/03/19-11:16: 1k tbn
2012/03/19-11:16: 60 tbc
2012/03/19-11:16: (default)
2012/03/19-11:16: Stream #0:1
2012/03/19-11:16: Audio: aac, 11025 Hz, mono, s16
2012/03/19-11:16: (default)
2012/03/19-11:16: Please use -b:a or -b:v, -b is ambiguous
2012/03/19-11:16: Incompatible pixel format 'yuv420p' for codec 'mjpeg', auto-selecting format 'yuvj420p'
2012/03/19-11:16: [buffer @ 02625fa0] w:640 h:480 pixfmt:yuv420p tb:1/1000000 sar:1/1 sws_param:
2012/03/19-11:16: [buffersink @ 025c3ea0] auto-inserting filter 'auto-inserted scale 0' between the filter 'src' and the filter 'out'
2012/03/19-11:16: [scale @ 0256b820] w:640 h:480 fmt:yuv420p -> w:640 h:480 fmt:yuvj420p flags:0x4
2012/03/19-11:16: Output #0, avi, to 'intput1.avi':
2012/03/19-11:16: Metadata:
2012/03/19-11:16: ISFT : Lavf53.31.100
2012/03/19-11:16: Stream #0:0
2012/03/19-11:16: Video: mjpeg (MJPG / 0x47504A4D), yuvj420p, 640x480 [SAR 1:1 DAR 4:3], q=2-31, 2500 kb/s
2012/03/19-11:16: 30 tbn
2012/03/19-11:16: 30 tbc
2012/03/19-11:16: (default)
2012/03/19-11:16: Stream #0:1
2012/03/19-11:16: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, 2 channels, s16, 1411 kb/s
2012/03/19-11:16: (default)
2012/03/19-11:16: Stream mapping:
2012/03/19-11:16: Stream #0:0 -> #0:0
2012/03/19-11:16: (h264 -> mjpeg)
2012/03/19-11:16: Stream #0:1 -> #0:1
2012/03/19-11:16: (aac -> pcm_s16le)
2012/03/19-11:16: Press [q] to stop, [?] for help
2012/03/19-11:16: frame= 79 fps= 0 q=24.8 size= 1562kB time=00:00:02.63 bitrate=4859.2kbits/s 
2012/03/19-11:16: frame= 149 fps=148 q=24.8 size= 2731kB time=00:00:04.96 bitrate=4504.8kbits/s 
2012/03/19-11:16: frame= 235 fps=155 q=24.8 size= 4170kB time=00:00:07.83 bitrate=4360.4kbits/s 
2012/03/19-11:16: frame= 325 fps=161 q=24.8 size= 5686kB time=00:00:10.83 bitrate=4300.0kbits/s 
2012/03/19-11:16: frame= 411 fps=163 q=24.8 size= 7154kB time=00:00:13.70 bitrate=4277.8kbits/s 
2012/03/19-11:16: frame= 500 fps=165 q=24.8 size= 8646kB time=00:00:16.66 bitrate=4249.9kbits/s 
2012/03/19-11:16: frame= 589 fps=167 q=24.8 size= 10114kB time=00:00:19.63 bitrate=4220.2kbits/s 
2012/03/19-11:16: frame= 676 fps=168 q=24.8 size= 11562kB time=00:00:22.53 bitrate=4203.5kbits/s 
2012/03/19-11:16: frame= 762 fps=169 q=24.8 Lsize= 12953kB time=00:00:25.07 bitrate=4231.6kbits/s 
2012/03/19-11:16: video:8599kB audio:4320kB global headers:0kB muxing overhead 0.265536%.

Can yout tell me why? Any reply is appreciated!
Thank you in advance!
 
Tom.chen.