1 /*****************************************************************************
2 * vlc_aout.h : audio output interface
3 *****************************************************************************
4 * Copyright (C) 2002-2011 VLC authors and VideoLAN
6 * Authors: Christophe Massiot <massiot@via.ecp.fr>
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU Lesser General Public License as published by
10 * the Free Software Foundation; either version 2.1 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public License
19 * along with this program; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
21 *****************************************************************************/
28 * This file defines functions, structures and macros for audio output object
31 /* Max number of pre-filters per input, and max number of post-filters */
32 #define AOUT_MAX_FILTERS 10
34 /* Buffers which arrive in advance of more than AOUT_MAX_ADVANCE_TIME
35 * will be considered as bogus and be trashed */
36 #define AOUT_MAX_ADVANCE_TIME (AOUT_MAX_PREPARE_TIME + CLOCK_FREQ)
38 /* Buffers which arrive in advance of more than AOUT_MAX_PREPARE_TIME
39 * will cause the calling thread to sleep */
40 #define AOUT_MAX_PREPARE_TIME (2 * CLOCK_FREQ)
42 /* Buffers which arrive after pts - AOUT_MIN_PREPARE_TIME will be trashed
43 * to avoid too heavy resampling */
44 #define AOUT_MIN_PREPARE_TIME AOUT_MAX_PTS_ADVANCE
46 /* Tolerance values from EBU Recommendation 37 */
47 /** Maximum advance of actual audio playback time to coded PTS,
48 * above which downsampling will be performed */
49 #define AOUT_MAX_PTS_ADVANCE (CLOCK_FREQ / 25)
51 /** Maximum delay of actual audio playback time from coded PTS,
52 * above which upsampling will be performed */
53 #define AOUT_MAX_PTS_DELAY (3 * CLOCK_FREQ / 50)
55 /* Max acceptable resampling (in %) */
56 #define AOUT_MAX_RESAMPLING 10
60 #define AOUT_FMTS_IDENTICAL( p_first, p_second ) ( \
61 ((p_first)->i_format == (p_second)->i_format) \
62 && AOUT_FMTS_SIMILAR(p_first, p_second) )
64 /* Check if i_rate == i_rate and i_channels == i_channels */
65 #define AOUT_FMTS_SIMILAR( p_first, p_second ) ( \
66 ((p_first)->i_rate == (p_second)->i_rate) \
67 && ((p_first)->i_physical_channels == (p_second)->i_physical_channels)\
68 && ((p_first)->i_original_channels == (p_second)->i_original_channels) )
70 #define AOUT_FMT_LINEAR( p_format ) \
71 (aout_BitsPerSample((p_format)->i_format) != 0)
73 #define VLC_CODEC_SPDIFL VLC_FOURCC('s','p','d','i')
74 #define VLC_CODEC_SPDIFB VLC_FOURCC('s','p','d','b')
76 #define AOUT_FMT_SPDIF( p_format ) \
77 ( ((p_format)->i_format == VLC_CODEC_SPDIFL) \
78 || ((p_format)->i_format == VLC_CODEC_SPDIFB) \
79 || ((p_format)->i_format == VLC_CODEC_A52) \
80 || ((p_format)->i_format == VLC_CODEC_DTS) )
82 /* This is heavily borrowed from libmad, by Robert Leslie <rob@mars.org> */
84 * Fixed-point format: 0xABBBBBBB
85 * A == whole part (sign + 3 bits)
86 * B == fractional part (28 bits)
88 * Values are signed two's complement, so the effective range is:
89 * 0x80000000 to 0x7fffffff
90 * -8.0 to +7.9999999962747097015380859375
92 * The smallest representable value is:
93 * 0x00000001 == 0.0000000037252902984619140625 (i.e. about 3.725e-9)
95 * 28 bits of fractional accuracy represent about
96 * 8.6 digits of decimal accuracy.
98 * Fixed-point numbers can be added or subtracted as normal
99 * integers, but multiplication requires shifting the 64-bit result
100 * from 56 fractional bits back to 28 (and rounding.)
102 typedef int32_t vlc_fixed_t
;
103 #define FIXED32_FRACBITS 28
104 #define FIXED32_MIN ((vlc_fixed_t) -0x80000000L)
105 #define FIXED32_MAX ((vlc_fixed_t) +0x7fffffffL)
106 #define FIXED32_ONE ((vlc_fixed_t) 0x10000000)
108 /* Values used for the audio-device and audio-channels object variables */
109 #define AOUT_VAR_MONO 1
110 #define AOUT_VAR_STEREO 2
111 #define AOUT_VAR_2F2R 4
112 #define AOUT_VAR_3F2R 5
113 #define AOUT_VAR_5_1 6
114 #define AOUT_VAR_6_1 7
115 #define AOUT_VAR_7_1 8
116 #define AOUT_VAR_SPDIF 10
118 #define AOUT_VAR_CHAN_UNSET 0 /* must be zero */
119 #define AOUT_VAR_CHAN_STEREO 1
120 #define AOUT_VAR_CHAN_RSTEREO 2
121 #define AOUT_VAR_CHAN_LEFT 3
122 #define AOUT_VAR_CHAN_RIGHT 4
123 #define AOUT_VAR_CHAN_DOLBYS 5
125 /*****************************************************************************
126 * Main audio output structures
127 *****************************************************************************/
129 /* Size of a frame for S/PDIF output. */
130 #define AOUT_SPDIF_SIZE 6144
132 /* Number of samples in an A/52 frame. */
133 #define A52_FRAME_NB 1536
135 /* FIXME to remove once aout.h is cleaned a bit more */
136 #include <vlc_block.h>
138 /** Audio output object */
143 audio_sample_format_t format
; /**< Output format (plugin can modify it
144 only when succesfully probed and not afterward) */
146 struct aout_sys_t
*sys
; /**< Output plugin private data */
147 void (*pf_play
)(audio_output_t
*, block_t
*, mtime_t
*); /**< Play callback
148 - queue a block for playback */
149 void (* pf_pause
)( audio_output_t
*, bool, mtime_t
); /**< Pause/resume
150 callback (optional, may be NULL) */
151 void (* pf_flush
)( audio_output_t
*, bool ); /**< Flush/drain callback
152 (optional, may be NULL) */
153 int (*volume_set
)(audio_output_t
*, float); /**< Volume setter (or NULL) */
154 int (*mute_set
)(audio_output_t
*, bool); /**< Mute setter (or NULL) */
157 void (*volume_report
)(audio_output_t
*, float);
158 void (*mute_report
)(audio_output_t
*, bool);
159 void (*policy_report
)(audio_output_t
*, bool);
160 int (*gain_request
)(audio_output_t
*, float);
165 * It describes the audio channel order VLC expect.
167 static const uint32_t pi_vlc_chan_order_wg4
[] =
169 AOUT_CHAN_LEFT
, AOUT_CHAN_RIGHT
,
170 AOUT_CHAN_MIDDLELEFT
, AOUT_CHAN_MIDDLERIGHT
,
171 AOUT_CHAN_REARLEFT
, AOUT_CHAN_REARRIGHT
, AOUT_CHAN_REARCENTER
,
172 AOUT_CHAN_CENTER
, AOUT_CHAN_LFE
, 0
175 /*****************************************************************************
177 *****************************************************************************/
180 * This function computes the reordering needed to go from pi_chan_order_in to
182 * If pi_chan_order_in or pi_chan_order_out is NULL, it will assume that vlc
183 * internal (WG4) order is requested.
185 VLC_API
int aout_CheckChannelReorder( const uint32_t *pi_chan_order_in
, const uint32_t *pi_chan_order_out
, uint32_t i_channel_mask
, int i_channels
, int *pi_chan_table
);
186 VLC_API
void aout_ChannelReorder( uint8_t *, int, int, const int *, int );
189 * This fonction will compute the extraction parameter into pi_selection to go
190 * from i_channels with their type given by pi_order_src[] into the order
191 * describe by pi_order_dst.
193 * - *pi_channels as the number of channels that will be extracted which is
194 * lower (in case of non understood channels type) or equal to i_channels.
195 * - the layout of the channels (*pi_layout).
197 * It will return true if channel extraction is really needed, in which case
198 * aout_ChannelExtract must be used
200 * XXX It must be used when the source may have channel type not understood
201 * by VLC. In this case the channel type pi_order_src[] must be set to 0.
202 * XXX It must also be used if multiple channels have the same type.
204 VLC_API
bool aout_CheckChannelExtraction( int *pi_selection
, uint32_t *pi_layout
, int *pi_channels
, const uint32_t pi_order_dst
[AOUT_CHAN_MAX
], const uint32_t *pi_order_src
, int i_channels
);
207 * Do the actual channels extraction using the parameters created by
208 * aout_CheckChannelExtraction.
210 * XXX this function does not work in place (p_dst and p_src must not overlap).
211 * XXX Only 8, 16, 24, 32, 64 bits per sample are supported.
213 VLC_API
void aout_ChannelExtract( void *p_dst
, int i_dst_channels
, const void *p_src
, int i_src_channels
, int i_sample_count
, const int *pi_selection
, int i_bits_per_sample
);
216 static inline unsigned aout_FormatNbChannels(const audio_sample_format_t
*fmt
)
218 return popcount(fmt
->i_physical_channels
);
221 VLC_API
unsigned int aout_BitsPerSample( vlc_fourcc_t i_format
) VLC_USED
;
222 VLC_API
void aout_FormatPrepare( audio_sample_format_t
* p_format
);
223 VLC_API
void aout_FormatPrint(vlc_object_t
*, const char *,
224 const audio_sample_format_t
*);
225 #define aout_FormatPrint(o, t, f) aout_FormatPrint(VLC_OBJECT(o), t, f)
226 VLC_API
const char * aout_FormatPrintChannels( const audio_sample_format_t
* ) VLC_USED
;
229 * Report change of configured audio volume to the core and UI.
231 static inline void aout_VolumeReport(audio_output_t
*aout
, float volume
)
233 aout
->event
.volume_report(aout
, volume
);
237 * Report change of muted flag to the core and UI.
239 static inline void aout_MuteReport(audio_output_t
*aout
, bool mute
)
241 aout
->event
.mute_report(aout
, mute
);
245 * Report audio policy status.
246 * \parm cork true to request a cork, false to undo any pending cork.
248 static inline void aout_PolicyReport(audio_output_t
*aout
, bool cork
)
250 aout
->event
.policy_report(aout
, cork
);
254 * Request a change of software audio amplification.
255 * \param gain linear amplitude gain (must be positive)
256 * \warning Values in excess 1.0 may cause overflow and distorsion.
258 static inline int aout_GainRequest(audio_output_t
*aout
, float gain
)
260 return aout
->event
.gain_request(aout
, gain
);
263 VLC_API
int aout_ChannelsRestart( vlc_object_t
*, const char *, vlc_value_t
, vlc_value_t
, void * );
266 VLC_API vout_thread_t
* aout_filter_RequestVout( filter_t
*, vout_thread_t
*p_vout
, video_format_t
*p_fmt
) VLC_USED
;
268 /** Audio output buffer FIFO */
276 /* Legacy packet-oriented audio output helpers */
280 aout_fifo_t partial
; /**< Audio blocks before packetization */
281 aout_fifo_t fifo
; /**< Packetized audio blocks */
282 mtime_t pause_date
; /**< Date when paused or VLC_TS_INVALID */
283 mtime_t time_report
; /**< Desynchronization estimate or VLC_TS_INVALID */
284 unsigned samples
; /**< Samples per packet */
285 bool starving
; /**< Whether currently starving (to limit error messages) */
288 VLC_DEPRECATED
void aout_PacketInit(audio_output_t
*, aout_packet_t
*, unsigned);
289 VLC_DEPRECATED
void aout_PacketDestroy(audio_output_t
*);
291 VLC_DEPRECATED
void aout_PacketPlay(audio_output_t
*, block_t
*, mtime_t
*);
292 VLC_DEPRECATED
void aout_PacketPause(audio_output_t
*, bool, mtime_t
);
293 VLC_DEPRECATED
void aout_PacketFlush(audio_output_t
*, bool);
295 VLC_DEPRECATED block_t
*aout_PacketNext(audio_output_t
*, mtime_t
) VLC_USED
;
298 #endif /* VLC_AOUT_H */