DIY Podcasting
Posted on Fri 12 August 2005 by alex in general
My Mum asked me how to save a Real stream so she can listen to it at a later date. Unfortunately although technically possible the player denies you this ability (there is a lesson about proprietary software for you). Although the BBC is experimenting with podcasting (AFAICT another name for putting mp3's on a webpage) they don't offer all their programs in this format yet.
Ideally what I need is an rtsp:// aware version of wget which can just save a stream. However in the meantime there is a workaround. First of all you need the URL of the stream. I used mplayerplug-in's
handy "Copy URL" facility although you could probably get the same result by looking in the .ram file which contains the list of streams. Then its just a case of using mplayer to play the stream to a raw wav file and then re-encoding it to mp3.
10:55 alexjb@okra [tmp] >mplayer rtsp://rmv8.bbc.net.uk/radio4/arts/book_week_tue.ra -ao pcm MPlayer 1.0pre7-SUSE-9.3-i586-Packman-3.3.5 (C) 2000-2005 MPlayer Team Playing rtsp://rmv8.bbc.net.uk/radio4/arts/book_week_tue.ra. Resolving rmv8.bbc.net.uk for AF_INET6... Couldn't resolve name for AF_INET6: rmv8.bbc.net.uk Resolving rmv8.bbc.net.uk for AF_INET... Connecting to server rmv8.bbc.net.uk[212.58.224.53]:554 ... Cache size set to 640 KBytes Connected to server: rmv8.bbc.net.uk Cache fill: 18.75% (122880 bytes) REAL file format detected. Stream description: audio/x-pn-multirate-realaudio logical stream Stream mimetype: audio/x-pn-realaudio Clip info: name: Book Of The Week - Tuesday author: BBC Radio 4 copyright: (C) British Broadcasting Corporation 2005 ========================================================================== Opening audio decoder: [realaud] RealAudio decoder opening shared obj '/usr/lib/codecs/cook.so' Audio codec: [23] 44 Kbps Stereo Music High Response - RealAudio Audio bitrate: 44.100 kbit/s (5513 bps) AUDIO: 44100 Hz, 2 ch, s16le, 44.1 kbit/3.13% (ratio: 5513->176400) Selected audio codec: [ra10cook] afm:realaud (RealPlayer 10 COOK audio) ========================================================================== Checking audio filter chain for 44100Hz/2ch/s16le -> 44100Hz/2ch/s16le... AF_pre: 44100Hz/2ch/s16le [AO PCM] File: audiodump.wav (WAVE) PCM: Samplerate: 44100Hz Channels: Stereo Format s16le [AO PCM] Info: fastest dumping is achieved with -vc dummy -vo null PCM: Info: to write WAVE files use -waveheader (default). AO: [pcm] 44100Hz 2ch s16le (2 bps) Building audio filter chain for 44100Hz/2ch/s16le -> 44100Hz/2ch/s16le... Starting playback... Stream EOF detected Exiting... (End of file) 11:11 alexjb@okra [tmp] >mv audiodump.wav tuesday.wav 11:11 alexjb@okra [tmp] >lame tuesday.wav tuesday.mp3 AME version 3.96.1 (http://lame.sourceforge.net/) Using polyphase lowpass filter, transition band: 17249 Hz - 17782 Hz Encoding tuesday.wav to tuesday.mp3 Encoding as 44.1 kHz 128 kbps j-stereo MPEG-1 Layer III (11x) qval=3 Frame | CPU time/estim | REAL time/estim | play/CPU | ETA 34417/34419 (100%)| 1:09/ 1:09| 1:15/ 1:15| 12.934x| 0:00 average: 128.0 kbps MS: 34420 (100.0%) Writing LAME Tag...done ReplayGain: -2.7dB
Et voila, an mp3 of a BBC realplayer stream.