realcap v 0.311
by fuzzbucket@eircom.net
http://homepage.eircom.net/~wastedyouth/realcap/
- What is realcap?
Realcap is a tool which, in conjunction with vsound, should allow you to capture Realaudio streams from Realplayer. It has been tested with Realplayer versions 8 and 10 for Linux.
The idea behind realcap was to have a way of recording and encoding Realaudio streams with the minimum of fuss and effort. One command should capture for any amount of time, encode and clean up uncompressed files as required.
- What do I need to run it?
You need Realplayer for Unix/Linux (http://www.real.com/) and the virtual audio loopback cable vsound (http://www.xenoclast.org/vsound/).
Also recommended are oggenc (http://www.xiph.org/ogg/vorbis/) for ogg vorbis encoding and lame (http://lame.sourceforge.net/) for mp3 encoding.
- How do I install it?
You can copy it to /usr/local/bin/ or your system's equivalent to make it available to all users.
You could also create a directory called 'bin' in your home directory and add it to your path by appending the following to ~/.bashrc
PATH=$PATH:~/bin
This will make it available to yourself for use in any location where you have write permission.
- How do I use it?
From the help file:
Usage: realcap [OPTIONS] URL/file
Most basic operation requires only the stream URL.
Available options:
-v, --version display version
-h, --help display this help text
-c, --captime duration of stream in seconds
remember to take initial buffering into account
(defaults to 1 hour)
-o, --oggbits nominal bitrate (kbps) of ogg vorbis output
if omitted ogg encoding will not occur
-m, --mp3bits constant bitrate (kbps) of mp3 output
if omitted mp3 encoding will not occur
-q, --oggquality ogg vorbis quality between 0 - 10, 10 being the
highest. Fractional values allowed
-a, --trackartist artists's name for ID3 tag in compressed output
file
-t, --tracktitle track title for ID3 tag in compressed output
file
-f, --filename all output files will be given this name.
do not provide an extension
(defaults to vsound.wav/ogg/mp3)
-d, --delete deletes wav file after recording if
ogg vorbis/mp3 bitrate is specified
(otherwise this parameter is ignored)
So, if you want to record for 20 minutes, encode to ogg at quality 2, add a title and artist and delete the uncompressed wav file you would issue the following:
realcap -c 1215 -q 2 -a foo -t bar -d rtsp://server.com/streams/real.smil
I tend to add 15-20 seconds to the capture time (-c) to allow for initial buffering.
- Notes
- During normal operation there should be no output from the sound card. It is recommended you run realcap in a directory with plenty of available space - around 23MB is required for each minute of recording. Final wav output is approximately 11MB for each minute recorded.
It should be possible to use realcap to schedule recordings with crond. If you decide to do this I recommend appending the date to the filename. I may go into more detail on this issue at a later date.
If you have any comments or suggestions about realcap please do not hesitate to contact me at fuzzbucket@eircom.net