/* WMix 3.0 -- a mixer using the OSS mixer API. * Copyright (C) 2000, 2001 * Daniel Richard G. , * timecop * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* WMVolume mixer interface * * Some notes: * * - The volume argument is a floating-point value between 0 (no sound) and * 1 (full sound) inclusively. * * - The balance argument is a floating-point value betwen -1 (full left) * and 1 (full right) inclusively. A value of 0 indicates centered sound. * If the device does not natively support a balance parameter, use the * lr_to_vb() and vb_to_lr() functions in misc.c. * * - The volume and balance arguments passed to these functions, given that * they are (usually 32-bit) floating-point values, may be capable of * specifying the audio parameters at a finer resolution than the * hardware itself. However, the mixer driver must not quantize the * volume and balance levels returned by the mixer_get_*() routines. * * Example: Suppose the mixer device supports specifying the volume as an * integer in the range of 0 to 100. If mixer_set_volume() is called with * an argument of 0.7351, then the device will be set to a volume of 74, * yet subsequent calls to mixer_get_volume() (assuming mixer state has * not changed since) will return 0.7351. Only if the mixer state is * changed by another program (that, say, sets the volume to 51) is the * value returned by this interface quantized (in such a case returning * 0.51). * * The reason why this quantization must be avoided whenever possible is * that otherwise, a large number of minuscule increases to the volume * level will have no cumulative effect. Calling mixer_set_volume_rel() * ten thousand times with an argument of 0.0001 should successfully * increase the volume to its maximum, even if the device actually * supports only 64 discrete volume levels. * * - Muting must occur independently of the volume level. */ void mixer_init (const char *mixer_device, bool verbose, const char *exclude[]); bool mixer_is_changed (void); int mixer_get_channel_count (void); int mixer_get_channel (void); const char * mixer_get_channel_name (void); const char * mixer_get_short_name (void); void mixer_set_channel (int channel); void mixer_set_channel_rel (int delta_channel); float mixer_get_volume (void); void mixer_set_volume (float volume); void mixer_set_volume_rel (float delta_volume); float mixer_get_balance (void); void mixer_set_balance (float balance); void mixer_set_balance_rel (float delta_balance); void mixer_toggle_mute (void); void mixer_toggle_rec (void); bool mixer_is_muted (void); bool mixer_is_stereo (void); bool mixer_is_rec (void); bool mixer_can_rec (void); bool is_exclude (const char *short_name, const char *exclude[]);