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SDL_audio.h
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2014 Sam Lantinga <slouken@libsdl.org>
4 
5  This software is provided 'as-is', without any express or implied
6  warranty. In no event will the authors be held liable for any damages
7  arising from the use of this software.
8 
9  Permission is granted to anyone to use this software for any purpose,
10  including commercial applications, and to alter it and redistribute it
11  freely, subject to the following restrictions:
12 
13  1. The origin of this software must not be misrepresented; you must not
14  claim that you wrote the original software. If you use this software
15  in a product, an acknowledgment in the product documentation would be
16  appreciated but is not required.
17  2. Altered source versions must be plainly marked as such, and must not be
18  misrepresented as being the original software.
19  3. This notice may not be removed or altered from any source distribution.
20 */
21 
28 #ifndef _SDL_audio_h
29 #define _SDL_audio_h
30 
31 #include "SDL_stdinc.h"
32 #include "SDL_error.h"
33 #include "SDL_endian.h"
34 #include "SDL_mutex.h"
35 #include "SDL_thread.h"
36 #include "SDL_rwops.h"
37 
38 #include "begin_code.h"
39 /* Set up for C function definitions, even when using C++ */
40 #ifdef __cplusplus
41 extern "C" {
42 #endif
43 
65 
69 /* @{ */
70 
71 #define SDL_AUDIO_MASK_BITSIZE (0xFF)
72 #define SDL_AUDIO_MASK_DATATYPE (1<<8)
73 #define SDL_AUDIO_MASK_ENDIAN (1<<12)
74 #define SDL_AUDIO_MASK_SIGNED (1<<15)
75 #define SDL_AUDIO_BITSIZE(x) (x & SDL_AUDIO_MASK_BITSIZE)
76 #define SDL_AUDIO_ISFLOAT(x) (x & SDL_AUDIO_MASK_DATATYPE)
77 #define SDL_AUDIO_ISBIGENDIAN(x) (x & SDL_AUDIO_MASK_ENDIAN)
78 #define SDL_AUDIO_ISSIGNED(x) (x & SDL_AUDIO_MASK_SIGNED)
79 #define SDL_AUDIO_ISINT(x) (!SDL_AUDIO_ISFLOAT(x))
80 #define SDL_AUDIO_ISLITTLEENDIAN(x) (!SDL_AUDIO_ISBIGENDIAN(x))
81 #define SDL_AUDIO_ISUNSIGNED(x) (!SDL_AUDIO_ISSIGNED(x))
82 
88 /* @{ */
89 #define AUDIO_U8 0x0008
90 #define AUDIO_S8 0x8008
91 #define AUDIO_U16LSB 0x0010
92 #define AUDIO_S16LSB 0x8010
93 #define AUDIO_U16MSB 0x1010
94 #define AUDIO_S16MSB 0x9010
95 #define AUDIO_U16 AUDIO_U16LSB
96 #define AUDIO_S16 AUDIO_S16LSB
97 /* @} */
98 
102 /* @{ */
103 #define AUDIO_S32LSB 0x8020
104 #define AUDIO_S32MSB 0x9020
105 #define AUDIO_S32 AUDIO_S32LSB
106 /* @} */
107 
111 /* @{ */
112 #define AUDIO_F32LSB 0x8120
113 #define AUDIO_F32MSB 0x9120
114 #define AUDIO_F32 AUDIO_F32LSB
115 /* @} */
116 
120 /* @{ */
121 #if SDL_BYTEORDER == SDL_LIL_ENDIAN
122 #define AUDIO_U16SYS AUDIO_U16LSB
123 #define AUDIO_S16SYS AUDIO_S16LSB
124 #define AUDIO_S32SYS AUDIO_S32LSB
125 #define AUDIO_F32SYS AUDIO_F32LSB
126 #else
127 #define AUDIO_U16SYS AUDIO_U16MSB
128 #define AUDIO_S16SYS AUDIO_S16MSB
129 #define AUDIO_S32SYS AUDIO_S32MSB
130 #define AUDIO_F32SYS AUDIO_F32MSB
131 #endif
132 /* @} */
133 
139 /* @{ */
140 #define SDL_AUDIO_ALLOW_FREQUENCY_CHANGE 0x00000001
141 #define SDL_AUDIO_ALLOW_FORMAT_CHANGE 0x00000002
142 #define SDL_AUDIO_ALLOW_CHANNELS_CHANGE 0x00000004
143 #define SDL_AUDIO_ALLOW_ANY_CHANGE (SDL_AUDIO_ALLOW_FREQUENCY_CHANGE|SDL_AUDIO_ALLOW_FORMAT_CHANGE|SDL_AUDIO_ALLOW_CHANNELS_CHANGE)
144 /* @} */
145 
146 /* @} *//* Audio flags */
147 
159 typedef void (SDLCALL * SDL_AudioCallback) (void *userdata, Uint8 * stream,
160  int len);
161 
165 typedef struct SDL_AudioSpec
166 {
167  int freq;
168  SDL_AudioFormat format;
174  SDL_AudioCallback callback;
175  void *userdata;
176 } SDL_AudioSpec;
177 
178 
179 struct SDL_AudioCVT;
180 typedef void (SDLCALL * SDL_AudioFilter) (struct SDL_AudioCVT * cvt,
181  SDL_AudioFormat format);
182 
186 #ifdef __GNUC__
187 /* This structure is 84 bytes on 32-bit architectures, make sure GCC doesn't
188  pad it out to 88 bytes to guarantee ABI compatibility between compilers.
189  vvv
190  The next time we rev the ABI, make sure to size the ints and add padding.
191 */
192 #define SDL_AUDIOCVT_PACKED __attribute__((packed))
193 #else
194 #define SDL_AUDIOCVT_PACKED
195 #endif
196 /* */
197 typedef struct SDL_AudioCVT
198 {
199  int needed;
200  SDL_AudioFormat src_format;
201  SDL_AudioFormat dst_format;
202  double rate_incr;
204  int len;
205  int len_cvt;
206  int len_mult;
207  double len_ratio;
208  SDL_AudioFilter filters[10];
211 
212 
213 /* Function prototypes */
214 
221 /* @{ */
222 extern DECLSPEC int SDLCALL SDL_GetNumAudioDrivers(void);
223 extern DECLSPEC const char *SDLCALL SDL_GetAudioDriver(int index);
224 /* @} */
225 
233 /* @{ */
234 extern DECLSPEC int SDLCALL SDL_AudioInit(const char *driver_name);
235 extern DECLSPEC void SDLCALL SDL_AudioQuit(void);
236 /* @} */
237 
242 extern DECLSPEC const char *SDLCALL SDL_GetCurrentAudioDriver(void);
243 
286 extern DECLSPEC int SDLCALL SDL_OpenAudio(SDL_AudioSpec * desired,
287  SDL_AudioSpec * obtained);
288 
299 
312 extern DECLSPEC int SDLCALL SDL_GetNumAudioDevices(int iscapture);
313 
327 extern DECLSPEC const char *SDLCALL SDL_GetAudioDeviceName(int index,
328  int iscapture);
329 
330 
344 extern DECLSPEC SDL_AudioDeviceID SDLCALL SDL_OpenAudioDevice(const char
345  *device,
346  int iscapture,
347  const
348  SDL_AudioSpec *
349  desired,
350  SDL_AudioSpec *
351  obtained,
352  int
353  allowed_changes);
354 
355 
356 
362 /* @{ */
363 typedef enum
364 {
365  SDL_AUDIO_STOPPED = 0,
366  SDL_AUDIO_PLAYING,
367  SDL_AUDIO_PAUSED
368 } SDL_AudioStatus;
369 extern DECLSPEC SDL_AudioStatus SDLCALL SDL_GetAudioStatus(void);
370 
371 extern DECLSPEC SDL_AudioStatus SDLCALL
372 SDL_GetAudioDeviceStatus(SDL_AudioDeviceID dev);
373 /* @} *//* Audio State */
374 
384 /* @{ */
385 extern DECLSPEC void SDLCALL SDL_PauseAudio(int pause_on);
386 extern DECLSPEC void SDLCALL SDL_PauseAudioDevice(SDL_AudioDeviceID dev,
387  int pause_on);
388 /* @} *//* Pause audio functions */
389 
409 extern DECLSPEC SDL_AudioSpec *SDLCALL SDL_LoadWAV_RW(SDL_RWops * src,
410  int freesrc,
411  SDL_AudioSpec * spec,
412  Uint8 ** audio_buf,
413  Uint32 * audio_len);
414 
419 #define SDL_LoadWAV(file, spec, audio_buf, audio_len) \
420  SDL_LoadWAV_RW(SDL_RWFromFile(file, "rb"),1, spec,audio_buf,audio_len)
421 
425 extern DECLSPEC void SDLCALL SDL_FreeWAV(Uint8 * audio_buf);
426 
436 extern DECLSPEC int SDLCALL SDL_BuildAudioCVT(SDL_AudioCVT * cvt,
437  SDL_AudioFormat src_format,
438  Uint8 src_channels,
439  int src_rate,
440  SDL_AudioFormat dst_format,
441  Uint8 dst_channels,
442  int dst_rate);
443 
454 extern DECLSPEC int SDLCALL SDL_ConvertAudio(SDL_AudioCVT * cvt);
455 
456 #define SDL_MIX_MAXVOLUME 128
457 
464 extern DECLSPEC void SDLCALL SDL_MixAudio(Uint8 * dst, const Uint8 * src,
465  Uint32 len, int volume);
466 
472 extern DECLSPEC void SDLCALL SDL_MixAudioFormat(Uint8 * dst,
473  const Uint8 * src,
474  SDL_AudioFormat format,
475  Uint32 len, int volume);
476 
485 /* @{ */
486 extern DECLSPEC void SDLCALL SDL_LockAudio(void);
487 extern DECLSPEC void SDLCALL SDL_LockAudioDevice(SDL_AudioDeviceID dev);
488 extern DECLSPEC void SDLCALL SDL_UnlockAudio(void);
489 extern DECLSPEC void SDLCALL SDL_UnlockAudioDevice(SDL_AudioDeviceID dev);
490 /* @} *//* Audio lock functions */
491 
495 extern DECLSPEC void SDLCALL SDL_CloseAudio(void);
496 extern DECLSPEC void SDLCALL SDL_CloseAudioDevice(SDL_AudioDeviceID dev);
497 
498 /* Ends C function definitions when using C++ */
499 #ifdef __cplusplus
500 }
501 #endif
502 #include "close_code.h"
503 
504 #endif /* _SDL_audio_h */
505 
506 /* vi: set ts=4 sw=4 expandtab: */
int len_cvt
Definition: SDL_audio.h:205
DECLSPEC SDL_AudioSpec *SDLCALL SDL_LoadWAV_RW(SDL_RWops *src, int freesrc, SDL_AudioSpec *spec, Uint8 **audio_buf, Uint32 *audio_len)
uint8_t Uint8
An unsigned 8-bit integer type.
Definition: SDL_stdinc.h:139
Definition: SDL_audio.h:165
DECLSPEC void SDLCALL SDL_CloseAudio(void)
DECLSPEC int SDLCALL SDL_OpenAudio(SDL_AudioSpec *desired, SDL_AudioSpec *obtained)
DECLSPEC void SDLCALL SDL_FreeWAV(Uint8 *audio_buf)
Uint16 padding
Definition: SDL_audio.h:172
uint32_t Uint32
An unsigned 32-bit integer type.
Definition: SDL_stdinc.h:155
int needed
Definition: SDL_audio.h:199
DECLSPEC const char *SDLCALL SDL_GetAudioDeviceName(int index, int iscapture)
Uint8 channels
Definition: SDL_audio.h:169
uint16_t Uint16
An unsigned 16-bit integer type.
Definition: SDL_stdinc.h:147
double rate_incr
Definition: SDL_audio.h:202
DECLSPEC void SDLCALL SDL_MixAudioFormat(Uint8 *dst, const Uint8 *src, SDL_AudioFormat format, Uint32 len, int volume)
DECLSPEC int SDLCALL SDL_GetNumAudioDevices(int iscapture)
Uint8 * buf
Definition: SDL_audio.h:203
#define SDL_AUDIOCVT_PACKED
Definition: SDL_audio.h:194
typedef void(SDLCALL *SDL_AudioCallback)(void *userdata
SDL_AudioFormat src_format
Definition: SDL_audio.h:200
struct SDL_AudioSpec SDL_AudioSpec
int len_mult
Definition: SDL_audio.h:206
DECLSPEC void SDLCALL SDL_MixAudio(Uint8 *dst, const Uint8 *src, Uint32 len, int volume)
double len_ratio
Definition: SDL_audio.h:207
Uint32 size
Definition: SDL_audio.h:173
SDL_AudioFormat format
Definition: SDL_audio.h:168
SDL_AudioFilter filters[10]
Definition: SDL_audio.h:208
Definition: SDL_audio.h:197
DECLSPEC int SDLCALL SDL_ConvertAudio(SDL_AudioCVT *cvt)
int len
Definition: SDL_audio.h:204
DECLSPEC int SDLCALL SDL_BuildAudioCVT(SDL_AudioCVT *cvt, SDL_AudioFormat src_format, Uint8 src_channels, int src_rate, SDL_AudioFormat dst_format, Uint8 dst_channels, int dst_rate)
Uint32 SDL_AudioDeviceID
Definition: SDL_audio.h:298
DECLSPEC const char *SDLCALL SDL_GetCurrentAudioDriver(void)
SDL_AudioFormat dst_format
Definition: SDL_audio.h:201
Uint16 SDL_AudioFormat
Audio format flags.
Definition: SDL_audio.h:64
Uint8 silence
Definition: SDL_audio.h:170
int filter_index
Definition: SDL_audio.h:209
Uint16 samples
Definition: SDL_audio.h:171
int freq
Definition: SDL_audio.h:167
DECLSPEC SDL_AudioDeviceID SDLCALL SDL_OpenAudioDevice(const char *device, int iscapture, const SDL_AudioSpec *desired, SDL_AudioSpec *obtained, int allowed_changes)
Definition: SDL_rwops.h:52