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I was able to convert the video from AVI to SWF however the sound seems to have been stripped out. I am running the following command

ffmpeg -i 1.avi -b:a 3000k -vcodec flv -ab 128k -ar 44100  -acodec libmp3lame -b:a 160k -ac 2 -ar 44100 output.swf

I attempted a similar conversion from MP4 to AVI and had no issues.

I am running Windows XP 32bit


I have included ffmpeg's output following the conversion. The only difference is that I am attempting to convert a MP4 file as opposed to an AVI but the results are the same i.e. a SWF file with video but no audio

ffmpeg version N-38632-g4cda8aa Copyright (c) 2000-2012 the FFmpeg developers
  built on Mar  8 2012 02:38:08 with gcc 4.5.0 20100414 (Fedora MinGW 4.5.0-1.fc
  configuration: --prefix=/var/www/users/research/ffmpeg/snapshots/build --arch=
x86 --target-os=mingw32 --cross-prefix=i686-pc-mingw32- --cc='ccache i686-pc-min
gw32-gcc' --enable-w32threads --enable-memalign-hack --enable-runtime-cpudetect
--enable-cross-compile --enable-static --disable-shared --extra-libs='-lws2_32 -
lwinmm' --extra-cflags='--static -I/var/www/users/research/ffmpeg/snapshots/buil
d/include' --extra-ldflags='-static -L/var/www/users/research/ffmpeg/snapshots/b
uild/lib' --enable-bzlib --enable-zlib --enable-gpl --enable-version3 --enable-n
onfree --enable-libx264 --enable-libspeex --enable-libtheora --enable-libvorbis
--enable-libfaac --enable-libxvid --enable-libopencore-amrnb --enable-libopencor
e-amrwb --enable-libmp3lame --enable-libvpx --disable-decoder=libvpx
  libavutil      51. 42.100 / 51. 42.100
  libavcodec     54. 10.100 / 54. 10.100
  libavformat    54.  2.100 / 54.  2.100
  libavdevice    53.  4.100 / 53.  4.100
  libavfilter     2. 63.100 /  2. 63.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0.  7.100 /  0.  7.100
  libpostproc    52.  0.100 / 52.  0.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '1.mp4':
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    creation_time   : 1970-01-01 00:00:00
    encoder         : Lavf53.0.3
  Duration: 00:02:41.04, start: 0.000000, bitrate: 2378 kb/s
    Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 1280x720,
 2253 kb/s, 24 fps, 24 tbr, 24 tbn, 48 tbc
      creation_time   : 1970-01-01 00:00:00
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, s16, 126
      creation_time   : 1970-01-01 00:00:00
      handler_name    :
[buffer @ 0x201de80] w:1280 h:720 pixfmt:yuv420p tb:1/1000000 sar:0/1 sws_param:

Output #0, swf, to '2.swf':
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    creation_time   : 1970-01-01 00:00:00
    encoder         : Lavf54.2.100
    Stream #0:0(und): Video: flv1, yuv420p, 1280x720, q=2-31, 200 kb/s, 90k tbn,
 24 tbc
      creation_time   : 1970-01-01 00:00:00
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: mp3, 44100 Hz, 2 channels, s16, 160 kb/s
      creation_time   : 1970-01-01 00:00:00
      handler_name    :
Stream mapping:
  Stream #0:0 -> #0:0 (h264 -> flv)
  Stream #0:1 -> #0:1 (aac -> libmp3lame)
Press [q] to stop, [?] for help
frame=   26 fps=0.0 q=7.1 size=     350kB time=00:00:01.07 bitrate=2675.6kbits/s
frame=   79 fps= 77 q=31.0 size=     612kB time=00:00:03.26 bitrate=1535.2kbits/
frame=  132 fps= 85 q=24.8 size=    1005kB time=00:00:05.48 bitrate=1500.1kbits/
frame=  192 fps= 93 q=24.8 size=    1255kB time=00:00:07.96 bitrate=1290.7kbits/
frame=  255 fps= 99 q=31.0 size=    1504kB time=00:00:10.60 bitrate=1161.8kbits/
frame=  308 fps=100 q=31.0 size=    1913kB time=00:00:12.82 bitrate=1222.0kbits/
frame=  363 fps=101 q=31.0 size=    2333kB time=00:00:15.09 bitrate=1265.6kbits/
frame=  426 fps=103 q=31.0 size=    2547kB time=00:00:17.71 bitrate=1177.9kbits/
frame=  482 fps=104 q=31.0 size=    2876kB time=00:00:20.06 bitrate=1174.5kbits/
frame=  541 fps=105 q=31.0 size=    3130kB time=00:00:22.51 bitrate=1138.6kbits/
frame=  601 fps=106 q=31.0 size=    3410kB time=00:00:25.02 bitrate=1116.1kbits/
frame=  656 fps=106 q=31.0 size=    3783kB time=00:00:27.32 bitrate=1134.1kbits/
frame=  712 fps=106 q=31.0 size=    4103kB time=00:00:29.62 bitrate=1134.6kbits/
frame=  771 fps=107 q=31.0 size=    4397kB time=00:00:32.07 bitrate=1122.8kbits/
frame=  831 fps=107 q=31.0 size=    4650kB time=00:00:34.58 bitrate=1101.4kbits/
frame=  880 fps=107 q=31.0 size=    5053kB time=00:00:36.64 bitrate=1129.4kbits/
frame=  932 fps=106 q=31.0 size=    5474kB time=00:00:38.81 bitrate=1155.3kbits/
frame=  990 fps=107 q=31.0 size=    5758kB time=00:00:41.22 bitrate=1144.3kbits/
frame= 1046 fps=107 q=31.0 size=    6049kB time=00:00:43.54 bitrate=1138.0kbits/
frame= 1097 fps=106 q=31.0 size=    6464kB time=00:00:45.66 bitrate=1159.6kbits/
frame= 1146 fps=106 q=31.0 size=    6824kB time=00:00:47.72 bitrate=1171.3kbits/
frame= 1196 fps=105 q=31.0 size=    7159kB time=00:00:49.81 bitrate=1177.3kbits/
frame= 1251 fps=105 q=31.0 size=    7497kB time=00:00:52.12 bitrate=1178.3kbits/
frame= 1304 fps=105 q=31.0 size=    7883kB time=00:00:54.30 bitrate=1189.0kbits/
frame= 1348 fps=105 q=31.0 size=    8278kB time=00:00:56.13 bitrate=1208.0kbits/
frame= 1396 fps=104 q=31.0 size=    8680kB time=00:00:58.14 bitrate=1222.8kbits/
frame= 1448 fps=104 q=31.0 size=    9111kB time=00:01:00.31 bitrate=1237.5kbits/
frame= 1501 fps=104 q=31.0 size=    9430kB time=00:01:02.51 bitrate=1235.7kbits/
frame= 1553 fps=104 q=31.0 size=    9765kB time=00:01:04.70 bitrate=1236.3kbits/
frame= 1607 fps=104 q=31.0 size=   10062kB time=00:01:06.92 bitrate=1231.6kbits/
frame= 1661 fps=104 q=31.0 size=   10443kB time=00:01:09.19 bitrate=1236.3kbits/
frame= 1714 fps=104 q=31.0 size=   10742kB time=00:01:11.39 bitrate=1232.6kbits/
frame= 1763 fps=104 q=31.0 size=   11198kB time=00:01:13.45 bitrate=1248.8kbits/
frame= 1817 fps=104 q=31.0 size=   11566kB time=00:01:15.70 bitrate=1251.6kbits/
frame= 1870 fps=104 q=31.0 size=   11986kB time=00:01:17.89 bitrate=1260.5kbits/
frame= 1923 fps=104 q=31.0 size=   12246kB time=00:01:20.09 bitrate=1252.5kbits/
frame= 1976 fps=104 q=31.0 size=   12636kB time=00:01:22.31 bitrate=1257.6kbits/
frame= 2031 fps=104 q=31.0 size=   12943kB time=00:01:24.61 bitrate=1253.2kbits/
frame= 2086 fps=104 q=31.0 size=   13338kB time=00:01:26.90 bitrate=1257.3kbits/
frame= 2145 fps=104 q=31.0 size=   13630kB time=00:01:29.33 bitrate=1249.8kbits/
frame= 2202 fps=104 q=31.0 size=   13920kB time=00:01:31.71 bitrate=1243.3kbits/
frame= 2262 fps=104 q=31.0 size=   14240kB time=00:01:34.19 bitrate=1238.4kbits/
frame= 2310 fps=104 q=31.0 size=   14637kB time=00:01:36.20 bitrate=1246.3kbits/
frame= 2360 fps=104 q=31.0 size=   14975kB time=00:01:38.32 bitrate=1247.7kbits/
frame= 2412 fps=104 q=24.8 size=   15335kB time=00:01:40.46 bitrate=1250.4kbits/
frame= 2470 fps=104 q=31.0 size=   15613kB time=00:01:42.89 bitrate=1243.0kbits/
frame= 2532 fps=104 q=24.8 size=   15861kB time=00:01:45.48 bitrate=1231.8kbits/
frame= 2584 fps=104 q=31.0 size=   16233kB time=00:01:47.65 bitrate=1235.3kbits/
frame= 2631 fps=104 q=31.0 size=   16599kB time=00:01:49.60 bitrate=1240.5kbits/
frame= 2676 fps=104 q=24.8 size=   17007kB time=00:01:51.49 bitrate=1249.6kbits/
frame= 2721 fps=103 q=31.0 size=   17335kB time=00:01:53.37 bitrate=1252.6kbits/
frame= 2767 fps=103 q=31.0 size=   17721kB time=00:01:55.27 bitrate=1259.3kbits/
frame= 2813 fps=103 q=31.0 size=   18150kB time=00:01:57.20 bitrate=1268.5kbits/
frame= 2869 fps=103 q=31.0 size=   18535kB time=00:01:59.53 bitrate=1270.3kbits/
frame= 2915 fps=103 q=31.0 size=   18909kB time=00:02:01.44 bitrate=1275.5kbits/
frame= 2961 fps=103 q=31.0 size=   19290kB time=00:02:03.37 bitrate=1280.9kbits/
frame= 3013 fps=103 q=31.0 size=   19567kB time=00:02:05.49 bitrate=1277.3kbits/
frame= 3064 fps=102 q=31.0 size=   19886kB time=00:02:07.66 bitrate=1276.1kbits/
frame= 3116 fps=102 q=31.0 size=   20170kB time=00:02:09.80 bitrate=1272.9kbits/
frame= 3166 fps=102 q=31.0 size=   20585kB time=00:02:11.89 bitrate=1278.5kbits/
frame= 3218 fps=102 q=31.0 size=   20885kB time=00:02:14.08 bitrate=1276.0kbits/
frame= 3269 fps=102 q=31.0 size=   21277kB time=00:02:16.17 bitrate=1280.0kbits/
frame= 3323 fps=102 q=31.0 size=   21502kB time=00:02:18.44 bitrate=1272.3kbits/
frame= 3375 fps=102 q=31.0 size=   21871kB time=00:02:20.59 bitrate=1274.4kbits/
frame= 3424 fps=102 q=31.0 size=   22230kB time=00:02:22.65 bitrate=1276.6kbits/
frame= 3474 fps=102 q=31.0 size=   22649kB time=00:02:24.74 bitrate=1281.8kbits/
frame= 3528 fps=102 q=24.8 size=   22928kB time=00:02:26.99 bitrate=1277.8kbits/
frame= 3582 fps=102 q=31.0 size=   23313kB time=00:02:29.23 bitrate=1279.7kbits/
frame= 3635 fps=102 q=31.0 size=   23651kB time=00:02:31.43 bitrate=1279.5kbits/
frame= 3687 fps=102 q=31.0 size=   24056kB time=00:02:33.62 bitrate=1282.8kbits/
frame= 3744 fps=102 q=24.8 size=   24467kB time=00:02:36.00 bitrate=1284.8kbits/
frame= 3799 fps=102 q=31.0 size=   24789kB time=00:02:38.27 bitrate=1283.0kbits/
frame= 3853 fps=102 q=31.0 Lsize=   25407kB time=00:02:40.54 bitrate=1296.4kbits
video:22162kB audio:3146kB global headers:0kB muxing overhead 0.386986%
share|improve this question
Complete ffmpeg console output missing. – LordNeckbeard May 13 '12 at 3:12
@LordNeckbeard - I have included the output. – PeanutsMonkey May 21 '12 at 20:03

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