RTMPDUMP issues with OSX 10.8 and Windows XP

[Aardvark]

As this problem is happening with both Windows XP and OSX 10.8, it did not make sense to me to pick one OS over the other. Under OSX, I am running VLC 2.0.3 and under Windows I am running the August 1st build of VLC 2.0.4. I am also running rtmpdump 2.4 on both platforms.

Basically I am performing the following command on the two platforms (on OSX the "vlc" command is "VLC"):

rtmpdump -v -r rtmp://cp80871.live.edgefcs.net/live/TOR680_AAC@14190 -o - | vlc -

On either platform, I will not hear anything until I kill rtmpdump. Once I do that, VLC starts playing what has been buffered up to the point I terminate rtmpdump. If I redirect rtmpdump's output to a file such as temp.flv, terminate it after several seconds and then cat/type the file to a pipe connected to VLC, it plays immediately. I am assuming there is a buffering issue with the pipes on both Windows and OSX but I am not sure if it is an rtmpdump issue or a VLC issue. The fact that cat/type to VLC works leads me to believe this is an rtmpdump issue.

I have searched the forums and others have reported seeing the same behavior but no one has ever responded with a solution that I can find.

[Rémi Denis-Courmont]

Replace vlc with cat, and you will see of rtmpdump outputs data reasonably fast.

[Aardvark]

That's the problem. Everything I test seems to show no problems with either rtmpdump or vlc. Piping rtmpdump to a file I see a very good transfer rate displayed by rtmpdump. cat/type on the file created and piping it to vlc works fine. Connecting rtmpdump directly to vlc and nothing. rtmpdump shows data coming in with the total KB counter and seconds incrementing. I was thinking the pipe may be buffering the data but OSX uses a 512 byte buffer and that should fill immediately. On Windows I believe it is 4096 bytes. Either way, enough data comes in relatively quickly to fill the buffer so I do not think that is the problem. Even if it was the maximum of 65536, it would fill in a few seconds. The fact that the behavior is consistent across two different OS platforms only adds to the puzzle.

UPDATE: If I use --stop with rtmpdump and specify for example 10 seconds (--stop 10), after the time elapses, the download completes and vlc starts playing the 10 seconds of audio downloaded.

UPDATE 2: I decided to experiment with older versions of vlc on Windows and after poking around with some real old versions, I found vlc 1.1.1 works. I am using the following command:

rtmpdump -v -r rtmp://cp80871.live.edgefcs.net/live/TOR680_AAC@14190 -o - | C:\vlc-1.1.1\vlc.exe -

I skipped from 1.0.1 to 1.1.1 so I am not sure if any intermediate versions are working. The above command will buffer about 13 seconds before the audio starts up and then the stream updates as needed (as reported by rtmpdump). vlc appears to control the flow of data from rtmpdump and pauses it until data is needed. I am guessing that something major changed in 2.0.0+ to break this.

So the problem is in vlc 2.0.0+ and not rtmpdump.