last changed 2002-03-20

Audio Recorder

This is a little harddisk recorder programm initially used to record audio data with an EDIROL UA-5 USB Audio Capture box and Sony VAIO Notebook running Linux

As this utility was written for a special task, for now there are some settings hardcoded. The utility uses the device /dev/dsp. It tries to set this device to 44.1kHz, 16bit, 2 channels.

Output always goes to the current directory into files named ###_track.raw, where ### is the the track# starting at 1.

If you start recording, the programm spawns two threads, one for reading the audio data from dsp and one for writing the audio data to the files. The original thread is used for graphical output of some interesting data about the read audio data and controls the two other threads, e.g. if you want to start a new track.

With the toolbar you can start recording a new track, pause the write thread, stop read and write thread, clear the global maximum value, enable fast view mode and set the number of the next track to record.

In the main area you can watch the maximum values of your samples calculated every tenth second. The range of those values is from 0 to 0x8000 as the absolute values are shown.

In the status bar the track#, the total recording time, the track time and the maximum values (left, right and max(left,right)) are shown.

The short cuts are Ctrl-R (start recording), Ctrl-P (Pause), Ctrl-S (Stop) and Ctrl-M (Clear Max).

The tracks are written in raw format. You can use sox to create wav files:
sox -s -w -c2 -r44100 001_track.raw 001_track.wav


You can download a tar file with a static linked binary, or the source code. If you want to compile the utility you also need qtgui as binary or as source and Qt 3.