This is SDL_audioin, a crossplatform library to add audio input support to SDL, modelled after SDL's audio output subsystem. Currently, it supports Linux® and Windows®, and I hope to complete a Macintosh OSX port someday. It is licensed under the GNU LGPL.
It includes with it a SDL_audioin-using version of SDL_Scope, which requires SDL_gfx.
Update -- echodemo 0.3 has been released, hopefully fixing a few porting issues. Also, SDL_audioin and echotest have been tested under cygwin.
Update -- version 0.3 rc1 has been released to fix a silly typo in the source that might cause a segfault if the device fails to open.
Update -- version 0.3 has been released to fix a major bug in the /dev/dsp audio driver. It now opens the audio device in nonblocking mode so that it will fail when another program is hogging the audio device instead of hanging forever.
Update -- version 0.2 has been released, including one minor and one major fix. The minor fix causes the Linux® backend to retry opening the audio device several times before giving up. The major fix causes the AudioSpecValid function to return 1 instead of some unknown value.
Update -- Michel Xhaard has written a nice and simple demo for SDL_audioin. It records sound and plays it right back, creating a nice echo effect. Check the downloads below for the source code.
Update -- The license on this software has been changed from the GNU GPL to the less restrictive GNU LGPL. This applies to SDL_audioin, Michel Xhaard's echodemo is still GPL.
Send comments, patches, ports etc to Tyler Montbriand, email@example.com.