1 /*****************************************************************************
2 * sdl.c : SDL audio output plugin for vlc
3 *****************************************************************************
4 * Copyright (C) 2000-2002 the VideoLAN team
7 * Authors: Michel Kaempf <maxx@via.ecp.fr>
8 * Sam Hocevar <sam@zoy.org>
9 * Pierre Baillet <oct@zoy.org>
10 * Christophe Massiot <massiot@via.ecp.fr>
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
25 *****************************************************************************/
27 /*****************************************************************************
29 *****************************************************************************/
30 #include <unistd.h> /* write(), close() */
35 #include SDL_INCLUDE_FILE
37 #define FRAME_SIZE 2048
39 /*****************************************************************************
40 * aout_sys_t: SDL audio output method descriptor
41 *****************************************************************************
42 * This structure is part of the audio output thread descriptor.
43 * It describes the specific properties of an audio device.
44 *****************************************************************************/
51 /*****************************************************************************
53 *****************************************************************************/
54 static int Open ( vlc_object_t * );
55 static void Close ( vlc_object_t * );
56 static void Play ( aout_instance_t * );
57 static void SDLCallback ( void *, byte_t *, int );
59 /*****************************************************************************
61 *****************************************************************************/
63 set_shortname( "SDL" );
64 set_description( _("Simple DirectMedia Layer audio output") );
65 set_capability( "audio output", 40 );
66 set_category( CAT_AUDIO );
67 set_subcategory( SUBCAT_AUDIO_AOUT );
68 add_shortcut( "sdl" );
69 set_callbacks( Open, Close );
72 /*****************************************************************************
73 * Open: open the audio device
74 *****************************************************************************/
75 static int Open ( vlc_object_t *p_this )
77 aout_instance_t *p_aout = (aout_instance_t *)p_this;
78 SDL_AudioSpec desired, obtained;
80 vlc_value_t val, text;
82 /* Check that no one uses the DSP. */
83 uint32_t i_flags = SDL_INIT_AUDIO;
84 if( SDL_WasInit( i_flags ) )
90 /* Win32 SDL implementation doesn't support SDL_INIT_EVENTTHREAD yet */
91 i_flags |= SDL_INIT_EVENTTHREAD;
94 /* In debug mode you may want vlc to dump a core instead of staying
96 i_flags |= SDL_INIT_NOPARACHUTE;
99 /* Initialize library */
100 if( SDL_Init( i_flags ) < 0 )
102 msg_Err( p_aout, "cannot initialize SDL (%s)", SDL_GetError() );
106 if ( var_Type( p_aout, "audio-device" ) != 0 )
108 /* The user has selected an audio device. */
110 var_Get( p_aout, "audio-device", &val );
111 if ( val.i_int == AOUT_VAR_STEREO )
113 p_aout->output.output.i_physical_channels
114 = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT;
116 else if ( val.i_int == AOUT_VAR_MONO )
118 p_aout->output.output.i_physical_channels = AOUT_CHAN_CENTER;
122 i_nb_channels = aout_FormatNbChannels( &p_aout->output.output );
123 if ( i_nb_channels > 2 )
125 /* SDL doesn't support more than two channels. */
127 p_aout->output.output.i_physical_channels
128 = AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT;
130 desired.freq = p_aout->output.output.i_rate;
131 desired.format = AUDIO_S16SYS;
132 desired.channels = i_nb_channels;
133 desired.callback = SDLCallback;
134 desired.userdata = p_aout;
135 desired.samples = FRAME_SIZE;
137 /* Open the sound device. */
138 if( SDL_OpenAudio( &desired, &obtained ) < 0 )
145 /* Now have a look at what we got. */
146 switch ( obtained.format )
149 p_aout->output.output.i_format = VLC_FOURCC('s','1','6','l'); break;
151 p_aout->output.output.i_format = VLC_FOURCC('s','1','6','b'); break;
153 p_aout->output.output.i_format = VLC_FOURCC('u','1','6','l'); break;
155 p_aout->output.output.i_format = VLC_FOURCC('u','1','6','b'); break;
157 p_aout->output.output.i_format = VLC_FOURCC('s','8',' ',' '); break;
159 p_aout->output.output.i_format = VLC_FOURCC('u','8',' ',' '); break;
161 /* Volume is entirely done in software. */
162 aout_VolumeSoftInit( p_aout );
164 if ( obtained.channels != i_nb_channels )
166 p_aout->output.output.i_physical_channels = (obtained.channels == 2 ?
167 AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT :
170 if ( var_Type( p_aout, "audio-device" ) == 0 )
172 var_Create( p_aout, "audio-device",
173 VLC_VAR_INTEGER | VLC_VAR_HASCHOICE );
174 text.psz_string = _("Audio Device");
175 var_Change( p_aout, "audio-device", VLC_VAR_SETTEXT, &text, NULL );
177 val.i_int = (obtained.channels == 2) ? AOUT_VAR_STEREO :
179 text.psz_string = (obtained.channels == 2) ? N_("Stereo") :
181 var_Change( p_aout, "audio-device",
182 VLC_VAR_ADDCHOICE, &val, &text );
183 var_AddCallback( p_aout, "audio-device", aout_ChannelsRestart,
187 else if ( var_Type( p_aout, "audio-device" ) == 0 )
190 var_Create( p_aout, "audio-device",
191 VLC_VAR_INTEGER | VLC_VAR_HASCHOICE );
192 text.psz_string = _("Audio Device");
193 var_Change( p_aout, "audio-device", VLC_VAR_SETTEXT, &text, NULL );
195 val.i_int = AOUT_VAR_STEREO;
196 text.psz_string = N_("Stereo");
197 var_Change( p_aout, "audio-device", VLC_VAR_ADDCHOICE, &val, &text );
198 val.i_int = AOUT_VAR_MONO;
199 text.psz_string = N_("Mono");
200 var_Change( p_aout, "audio-device", VLC_VAR_ADDCHOICE, &val, &text );
201 if ( i_nb_channels == 2 )
203 val.i_int = AOUT_VAR_STEREO;
207 val.i_int = AOUT_VAR_MONO;
209 var_Change( p_aout, "audio-device", VLC_VAR_SETDEFAULT, &val, NULL );
210 var_AddCallback( p_aout, "audio-device", aout_ChannelsRestart, NULL );
213 val.b_bool = VLC_TRUE;
214 var_Set( p_aout, "intf-change", val );
216 p_aout->output.output.i_rate = obtained.freq;
217 p_aout->output.i_nb_samples = obtained.samples;
218 p_aout->output.pf_play = Play;
223 /*****************************************************************************
224 * Play: play a sound samples buffer
225 *****************************************************************************/
226 static void Play( aout_instance_t * p_aout )
230 /*****************************************************************************
231 * Close: close the audio device
232 *****************************************************************************/
233 static void Close ( vlc_object_t *p_this )
237 SDL_QuitSubSystem( SDL_INIT_AUDIO );
240 /*****************************************************************************
241 * SDLCallback: what to do once SDL has played sound samples
242 *****************************************************************************/
243 static void SDLCallback( void * _p_aout, byte_t * p_stream, int i_len )
245 aout_instance_t * p_aout = (aout_instance_t *)_p_aout;
246 aout_buffer_t * p_buffer;
248 /* SDL is unable to call us at regular times, or tell us its current
249 * hardware latency, or the buffer state. So we just pop data and throw
250 * it at SDL's face. Nah. */
252 vlc_mutex_lock( &p_aout->output_fifo_lock );
253 p_buffer = aout_FifoPop( p_aout, &p_aout->output.fifo );
254 vlc_mutex_unlock( &p_aout->output_fifo_lock );
256 if ( p_buffer != NULL )
258 p_aout->p_libvlc->pf_memcpy( p_stream, p_buffer->p_buffer, i_len );
259 aout_BufferFree( p_buffer );
263 p_aout->p_libvlc->pf_memset( p_stream, 0, i_len );