it's very interesting to follow the development of the Open-Source software DReaM
If compiled from the latest CVS sources
(published at SourceForge.net) you will notice some exciting improvements:
- There's a new option in the Evaluation Dialogue: Audio Spectrum
If the button is activated the graphic display will show the frequency spectrum of the decoded audio. It's not very detailed but you get a good impression about the audio bandwidth of the transmitted DRM signal (see attached screenshot).
- DReaM scans the entire frequency range of the soundcard to find a DRM signal and that can take some time. If your receiver supplies a stable IF signal (e.g. 12 kHz) you can narrow the search window for the frequency acquisition by starting the program with command line arguments -E and -S.
Example: "dream -E 12000 -S 100" would mean, that the search window is centered around 12 kHz and the width is 100 Hz.
- In transmitter mode (command line argument -t) DReaM is now not only able to generate a picture (MOT) slide show but to encode AAC audio!
The sound quality is still rather poor (AAC Mono without SBR) as the used FAAC library isn't optimized for DRM (yet). Nevertheless you can do some interesting experiments.
(How to get the DReaM transmitter AAC capable is explained here.)
There's only one really important feature still missing: Stereo decoding.
I wouldn't be surprised if that would be achieved within the next few month...
Regards - DigiBC