On 12-Feb-05 MJ Ray wrote:

Tony wrote:

...

Make a cable to go from the 'audio out' jack on your soundcard to the 'Aux' input of an amplifier, connect the tape recorder to the amp in the usual way, adjust levels to suit, restart file on BBC site and then just 'listen again' on the amp's speakers while the programme is recording.

This is what I'd already been doing, in effect, though I'd found that I get more pleasant quality by putting a mike in front of the speakers and recording to tape through that. (You shouldn't do the washing-up or emit bodily noises while doing it this way, though).

I think you can probably connect them in software using an ALSA config file .asoundrc but I don't know the incantations. Then you could capture the PCM as it's sent to the speakers.

This is why audio with Digital Rights Restriction Technology is silly. It's always possible to hack yourself in somewhere along the line unless the entire digital system is a sealed unit from backing store to output socket - even then we will probably get Digital->Analogue->Digital conversions that are near enough lossless eventually. Audio will come before video, based on experience, but both will happen if there's demand for it...

Thanks to all and especially MJR (above) who got me googling again, which led me to vsound:

http://www.zorg.org/vsound/index.shtml

which acts along the lines he describes:

"This program allows you to record the output of any standard OSS program (one that uses /dev/dsp for sound) without having to modify or recompile the program. It uses the same idea as the esddsp wrapper from the Enlightened Sound Daemon (in fact, vsound is based on esddsp). That is, it preloads a library that intercepts calls to open /dev/dsp, and instead returns a handle to a normal file. It also intercepts ioctl's on that file handle and logs them, to help convert the audio data from its raw form. Vsound then uses sox to convert the raw data to the desired file format.

The upshoot of this is that instead of playing sound to the sound card in your computer, the data is recorded to a file. This is similar to if you connected a loopback cable to the line in and line out jacks on your sound card, but no DA or AD conversions take place, so quality is not lost.

One use of vsound is to help convert real audio files to some other format. Since the real audio format is proprietary, and all we have is a player, we can use the vsound to create a wave file like so:

vsound -f output.wav realplay input.rm

This will run realplayer under vsound. You will notice that no sound is produced while the real audio file is being played. When the file has completed playing, exit realplayer, and the raw audio data will be converted to a wave file.

I downloaded the vsound source, a mere 188KB, and it compiled very quickly:

./configure make make install

The result is very compact: a 5675-byte sheel script "vsound", a 41680-byte library file "vsound.lo2 and a sym-link to this, and a 656-byte libtool text file "libvsound.la".

Then I tested it with

vsound -t -f output.wav realplay \ rtsp://rmv8.bbc.net.uk/radio4/news/yip_thu.ra

where the URL was copied from a ram file "yip.ram" I had downloaded from the BBC. This is for "Yesterday in Parliament" and it was done on a Friday so it's the Thursday edition.

The "-t" option I used (as opposed to the example in the README) is needed to cope with breaks in the stream download. If you don't put it in then vsound bombs out when the stream is interuupted.

After about 5 minutes I decided to halt it ("stop button" on RealPlayer) and then kill ("^C") vsound. The result was duly 5 minutes of "Yesterday in Parliament" in a ".wav" file.

It looks as though this means I can now store my own ".wav" files of any BBC audio broadcast accessible by RealPlayer.

(You will tend to get big files, though: about 0.5MB/minute).

Of course it won't work with streaming video, but there are hints on the vsound website about this, and for those who can manage to install it probably mplayer will work too.

Thanks for all the comments and help. I'm pleased with this outcome!

Best wishes to all, Ted.

-------------------------------------------------------------------- E-Mail: (Ted Harding) Ted.Harding@nessie.mcc.ac.uk Fax-to-email: +44 (0)870 094 0861 Date: 12-Feb-05 Time: 11:36:16 ------------------------------ XFMail ------------------------------