Low level audio programming

I wonder; does audio software like Cubase and Audacity use PlaySound calls??

Where can I learn about low level audio programming? As far as I've found information on the web, MCI seems to be the lowest level audio API in Windows...

Thanks

Edit: I do开发者_开发问答n't ask for information specific for Windows only.

There's several audio APIs to choose from. The oldest and most widely supported is the waveOut API - look for functions starting with waveOut in MSDN. A slightly newer one is DirectSound which is geared more towards games, but it's main feature over waveOut is positional 3D sound which professional audio software doesn't use (it was also supposed to have lower latency than waveOut, but that never really materialized). For low latency audio, there is ASIO. Professional audio apps support this API, but not all drivers do (it's a standard feature in professional sound cards, but not gaming or on-board hardware). ASIO can provide much lower latency than waveOut or DirectSound. Finally, there's the kernel streaming interface, which is the lowest-level audio interface still accessible from user-mode code. This is a direct pipe into Windows's internal mixer which combines output from all apps that are currently playing sound into the signal that gets sent to the sound card. It's scarcely documented though. There's a driver called ASIO4ALL (just google it) that provides ASIO support on soundcards without ASIO drivers by implementing the ASIO API on top of the kernel streaming interface.

I'm a little late to the game here, but I posted a Windows API history last week that might add a little more context. The choice of API really depends on your needs. If you want to avoid 3rd party libraries, it really only comes down to MME, XAudio2, and Core Audio (WASAPI).

A Brief History of Windows Audio APIs

Hope this helps!

Actually, if you are looking for more than Windows-only output support, then the best way to start is to review Phil Burk's PortAudio, available as of this writing at http://www.portaudio.com/ .

ASIO is a good quality interface, but it's proprietary and owned by Steinberg.

There are many lower-level interfaces to audio output than MCI in modern Windows. These include, at least, DirectSound, XAudio and WASAPI.

I recommend avoiding the Windows APIs as much as possible, and learning PortAudio instead.