Beat DetectionAlthough beat detection is generally rather hard, Eric Schierer (MIT) wrote a fairly good paper on the subject. His source code, somewhat modified to actually run on my computer, is here. I also found an email with his notes.
The paper has much good advice on using the `tapping' program provided.
A different attempt is pitchtrack. Source code (again slightly modified to ease compilation) can be found here.
Pitchtrack requires the fftw package. Debian users can 'apt-get install fftw-dev'. Dave recommends the "compact ascii form" of output, enabled with the -f -c flags.
Sound Card Support
- Commercial OSS Sound Drivers - a set of proprietary drivers completely compatible with the OSS-Lite modules normally in the kernel. A powerful config utility can autodetect and configure most sound cards. A license costs $20-$50 depending on which cards it will control. A free trial license lets users try out support for their cards at no expense. Multiple sound cards made easy.
- ALSA Sound Drivers - a set of kernel modules and utilities designed as a more powerful alternative to the standard sound card modules. Features backward compatibility with OSS-Lite and old /dev/dsp devices. Multiple sound cards supported.
- Midi controllers available from various manufacturers.
- More links to midi controllers.
- German page of alternative midi controllers.
- Do It Yourself midi controllers, introduction and links.
- Huge list of computer input devices. Many of these devices would make great hardware for gdam, if a simple driver were written.
Sound Quality and Latency
- Linux Audio Quality HOWTO.
- The Low Latency HOWTO includes links to patched 2.2 kernel sources.
- Linux Scheduling Latency "contains a collection of notes and tools related to an effort to decrease the typical scheduling latency of the 2.4.x kernel."
Experimental Realtime and Preemption Kernel Patches from MontaVista. Exciting work on improving realtime performance. Patches for 2.4.0-test6, info files, and general scheduling-related utilities.
- Tips on reducing sound card noise.
- LADSPA is a simple plugin format. GDAM can create and load ladspa plugins.
- linuxdj.com hosts various sites related to linux audio, including the linux-audio-development mailing list.
- Suggestions from Adrian Freed on "Improving Music GUIs".
- Free Music Philosophy