Introduction

RTMP is the binary protocol used for streaming flash movies.

It usually lives on port 1935.

To learn about RTMP I used the following references:

• http://wiki.gnashdev.org/RTMP
• http://www.actionscript.org/resources/articles/630/1/Low-level-AS3---Establishing-an-RTMP-connection-with-Socket-and-ByteArray/Page1.html
• https://trac.videolan.org/vlc/browser/modules/access/rtmp/rtmp_amf_flv.c
• http://osflash.org/flv
• http://code.google.com/p/erlyvideo/wiki/StreamNotes
• http://www.mail-archive.com/osflash@osflash.org/msg09727.html

But it must be said it still took a little effort to piece it all together... :-)

Implementation

src/rtmp_client.erl

This is a very stripped down RTMP client - in fact I've only implemented enough of the protocol to extract audio streams from the BBC iPlayer.

src/ems_amf.erl src/ems_rtmp.erl

These modules provide encoders/ decoders for the binary formats used in RTMP. They're borrowed from the erlmedia project. I'm a little ashamed I haven't managed to use more of their literate code :-(

Limitations

Currently the flash streaming server kicks my client off after about 10 minutes of streaming.