[FFmpeg-user] ffmpeg read from UDP/Port

[Bill Davidsen]

Alex Lin wrote:
> Hi all,
>
> I am using Windows 7 64 bit, and I downloaded the 64 bit version of
> ffmpeg: ffmpeg-20140916-git-b76d613-win64-static.7z
>
> I have spent the entire day experimenting with ffmpeg today but I haven't
> quite figure out if ffmpeg is the right solution to my problem yet, so I
> would like to get some opinions.
>
> I am receiving H264 encoded packets through RTP with sample rate of 90,000,
> and I need to record these packets. The file format doesn't really matter
> at this point.
>
> Currently, I have a server sending the H264 packets to port 50002 of my
> machine (192.168.1.200), so I run the following ffmpeg command on my
> machine:
>
> ffmpeg -i udp://192.168.1.200:50002 -f mp4 hello.mp4

I might be tempted to set both video and audio codec to copy, and save in a .TS 
file without -f at all.
If that works you can capture the information and then play with it from the 
file. I am a Linux user,
so you may need guidance for Windows issues from an expert, but if you can 
capture the data you
eliminate some possible problems by not reformatting the data at capture.
>
> Then the following shows
>
> ffmpeg version N-66289-gb76d613 Copyright (c) 2000-2014 the FFmpeg
> developers
>    built on Sep 15 2014 22:11:04 with gcc 4.8.3 (GCC)
>    configuration: --enable-gpl --enable-version3 --disable-w32threads
> --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r
> --enable-gnutls --enable-iconv --enable-libass --enable-libbluray
> --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme
> --enable-libgsm --enable-
> libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb
> --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus
> --enable-librtmp --enable-libschroedinger --enable-libsoxr
> --enable-libspeex --enable-libtheora --enable-libtwolame
> --enable-libvidstab --enable-libvo-aacenc --
> enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx
> --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265
> --enable-libxavs --enable-libxvid --enable-decklink --enable-zlib
>    libavutil      54.  7.100 / 54.  7.100
>    libavcodec     56.  1.100 / 56.  1.100
>    libavformat    56.  4.101 / 56.  4.101
>    libavdevice    56.  0.100 / 56.  0.100
>    libavfilter     5.  1.100 /  5.  1.100
>    libswscale      3.  0.100 /  3.  0.100
>    libswresample   1.  1.100 /  1.  1.100
>    libpostproc    53.  0.100 / 53.  0.100
>
> The server starts sending video packets, and nothing happens on the command
> prompt with the ffmpeg command.
> The server stops sending video packets, and nothing happens still (I waited
> for at least 5 minutes), so I pressed Ctrl+C, then I see this
>
> udp://192.168.1.200:50002: Invalid data found when processing input
> Received signal 2: terminating.
>
> am I using ffmpeg correctly? and are the H264 packets I am receiving not
> supported?
> I have looked around and did not see any debug log generated by ffmpeg, so
> I don't really know where else to look.
> If it is necessary, I can provide a packet capture with the H264 packets.
>

-- 
bill davidsen <davidsen at tmr.com>
   CTO TMR Associates, Inc
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