5 * These are what the 16 bits in SDL_AudioFormat currently mean...
6 * (Unspecified bits are always zero).
9 ++-----------------------sample is signed if set
11 || ++-----------sample is bigendian if set
13 || || ++---sample is float if set
15 || || || +---sample bit size---+
17 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
19 * There are macros in SDL 2.0 and later to query these bits.
22 TSDL_AudioFormat = UInt16;
28 SDL_AUDIO_MASK_BITSIZE = ($FF);
29 SDL_AUDIO_MASK_DATATYPE = (1 shl 8);
30 SDL_AUDIO_MASK_ENDIAN = (1 shl 12);
31 SDL_AUDIO_MASK_SIGNED = (1 shl 15);
33 function SDL_AUDIO_BITSIZE(x: Cardinal): Cardinal;
34 function SDL_AUDIO_ISFLOAT(x: Cardinal): Cardinal;
35 function SDL_AUDIO_ISBIGENDIAN(x: Cardinal): Cardinal;
36 function SDL_AUDIO_ISSIGNED(x: Cardinal): Cardinal;
37 function SDL_AUDIO_ISINT(x: Cardinal): Cardinal;
38 function SDL_AUDIO_ISLITTLEENDIAN(x: Cardinal): Cardinal;
39 function SDL_AUDIO_ISUNSIGNED(x: Cardinal): Cardinal;
44 * Defaults to LSB byte order.
47 AUDIO_U8 = $0008; {**< Unsigned 8-bit samples *}
48 AUDIO_S8 = $8008; {**< Signed 8-bit samples *}
49 AUDIO_U16LSB = $0010; {**< Unsigned 16-bit samples *}
50 AUDIO_S16LSB = $8010; {**< Signed 16-bit samples *}
51 AUDIO_U16MSB = $1010; {**< As above, but big-endian byte order *}
52 AUDIO_S16MSB = $9010; {**< As above, but big-endian byte order *}
53 AUDIO_U16 = AUDIO_U16LSB;
54 AUDIO_S16 = AUDIO_S16LSB;
60 AUDIO_S32LSB = $8020; {**< 32-bit integer samples *}
61 AUDIO_S32MSB = $9020; {**< As above, but big-endian byte order *}
62 AUDIO_S32 = AUDIO_S32LSB;
68 AUDIO_F32LSB = $8120; {**< 32-bit floating point samples *}
69 AUDIO_F32MSB = $9120; {**< As above, but big-endian byte order *}
70 AUDIO_F32 = AUDIO_F32LSB;
73 * Native audio byte ordering
76 #if SDL_BYTEORDER == SDL_LIL_ENDIAN
77 #define AUDIO_U16SYS AUDIO_U16LSB
78 #define AUDIO_S16SYS AUDIO_S16LSB
79 #define AUDIO_S32SYS AUDIO_S32LSB
80 #define AUDIO_F32SYS AUDIO_F32LSB
82 #define AUDIO_U16SYS AUDIO_U16MSB
83 #define AUDIO_S16SYS AUDIO_S16MSB
84 #define AUDIO_S32SYS AUDIO_S32MSB
85 #define AUDIO_F32SYS AUDIO_F32MSB
91 * Which audio format changes are allowed when opening a device.
94 SDL_AUDIO_ALLOW_FREQUENCY_CHANGE = $00000001;
95 SDL_AUDIO_ALLOW_FORMAT_CHANGE = $00000002;
96 SDL_AUDIO_ALLOW_CHANNELS_CHANGE = $00000004;
97 SDL_AUDIO_ALLOW_ANY_CHANGE = (SDL_AUDIO_ALLOW_FREQUENCY_CHANGE or
98 SDL_AUDIO_ALLOW_FORMAT_CHANGE or
99 SDL_AUDIO_ALLOW_CHANNELS_CHANGE);
104 * This function is called when the audio device needs more data.
106 * userdata An application-specific parameter saved in
107 * the SDL_AudioSpec structure
108 * stream A pointer to the audio data buffer.
109 * len The length of that buffer in bytes.
111 * Once the callback returns, the buffer will no longer be valid.
112 * Stereo samples are stored in a LRLRLR ordering.
115 TSDL_AudioCallback = procedure(userdata: Pointer; stream: PUInt8; len: Integer);
118 * The calculated values in this structure are calculated by SDL_OpenAudio().
121 PSDL_AudioSpec = ^TSDL_AudioSpec;
122 TSDL_AudioSpec = record
123 freq: Integer; {**< DSP frequency -- samples per second *}
124 format: TSDL_AudioFormat; {**< Audio data format *}
125 channels: UInt8; {**< Number of channels: 1 mono, 2 stereo *}
126 silence: UInt8; {**< Audio buffer silence value (calculated) *}
127 samples: UInt16; {**< Audio buffer size in samples (power of 2) *}
128 padding: UInt16; {**< Necessary for some compile environments *}
129 size: UInt32; {**< Audio buffer size in bytes (calculated) *}
130 callback: TSDL_AudioCallback;
134 PSDL_AudioCVT = ^TSDL_AudioCVT;
135 TSDL_AudioFilter = procedure(cvt: PSDL_AudioCVT; format: TSDL_AudioFormat);
138 * A structure to hold a set of audio conversion filters and buffers.
140 TSDL_AudioCVT = record
141 needed: Integer; {**< Set to 1 if conversion possible *}
142 src_format: TSDL_AudioFormat; {**< Source audio format *}
143 dst_format: TSDL_AudioFormat; {**< Target audio format *}
144 rate_incr: Double; {**< Rate conversion increment *}
145 buf: PUInt8; {**< Buffer to hold entire audio data *}
146 len: Integer; {**< Length of original audio buffer *}
147 len_cvt: Integer; {**< Length of converted audio buffer *}
148 len_mult: Integer; {**< buffer must be len*len_mult big *}
149 len_ratio: Double; {**< Given len, final size is len*len_ratio *}
150 filters: array[0..9] of TSDL_AudioFilter; {**< Filter list *}
151 filter_index: Integer; {**< Current audio conversion function *}
155 {* Function prototypes *}
158 * Driver discovery functions
160 * These functions return the list of built in audio drivers, in the
161 * order that they are normally initialized by default.
164 function SDL_GetNumAudioDrivers: Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetNumAudioDrivers' {$ENDIF} {$ENDIF};
165 function SDL_GetAudioDriver(index: Integer): PAnsiChar cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetAudioDriver' {$ENDIF} {$ENDIF};
168 * Initialization and cleanup
170 * These functions are used internally, and should not be used unless
171 * you have a specific need to specify the audio driver you want to
172 * use. You should normally use SDL_Init() or SDL_InitSubSystem().
175 function SDL_AudioInit(driver_name: PAnsiChar): Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_AudioInit' {$ENDIF} {$ENDIF};
176 procedure SDL_AudioQuit cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_AudioQuit' {$ENDIF} {$ENDIF};
179 * This function returns the name of the current audio driver, or NULL
180 * if no driver has been initialized.
182 function SDL_GetCurrentAudioDriver: PAnsiChar cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetCurrentAudioDriver' {$ENDIF} {$ENDIF};
185 * This function opens the audio device with the desired parameters, and
186 * returns 0 if successful, placing the actual hardware parameters in the
187 * structure pointed to by obtained. If obtained is NULL, the audio
188 * data passed to the callback function will be guaranteed to be in the
189 * requested format, and will be automatically converted to the hardware
190 * audio format if necessary. This function returns -1 if it failed
191 * to open the audio device, or couldn't set up the audio thread.
193 * When filling in the desired audio spec structure,
194 * - desired->freq should be the desired audio frequency in samples-per-
196 * - desired->format should be the desired audio format.
197 * - desired->samples is the desired size of the audio buffer, in
198 * samples. This number should be a power of two, and may be adjusted by
199 * the audio driver to a value more suitable for the hardware. Good values
200 * seem to range between 512 and 8096 inclusive, depending on the
201 * application and CPU speed. Smaller values yield faster response time,
202 * but can lead to underflow if the application is doing heavy processing
203 * and cannot fill the audio buffer in time. A stereo sample consists of
204 * both right and left channels in LR ordering.
205 * Note that the number of samples is directly related to time by the
206 * following formula: ms := (samples*1000)/freq;
207 * - desired->size is the size in bytes of the audio buffer, and is
208 * calculated by SDL_OpenAudio().
209 * - desired->silence is the value used to set the buffer to silence,
210 * and is calculated by SDL_OpenAudio().
211 * - desired->callback should be set to a function that will be called
212 * when the audio device is ready for more data. It is passed a pointer
213 * to the audio buffer, and the length in bytes of the audio buffer.
214 * This function usually runs in a separate thread, and so you should
215 * protect data structures that it accesses by calling SDL_LockAudio()
216 * and SDL_UnlockAudio() in your code.
217 * - desired->userdata is passed as the first parameter to your callback
220 * The audio device starts out playing silence when it's opened, and should
221 * be enabled for playing by calling SDL_PauseAudio(0) when you are ready
222 * for your audio callback function to be called. Since the audio driver
223 * may modify the requested size of the audio buffer, you should allocate
224 * any local mixing buffers after you open the audio device.
226 function SDL_OpenAudio(desired: PSDL_AudioSpec; obtained: PSDL_AudioSpec): Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_OpenAudio' {$ENDIF} {$ENDIF};
229 * SDL Audio Device IDs.
231 * A successful call to SDL_OpenAudio() is always device id 1, and legacy
232 * SDL audio APIs assume you want this device ID. SDL_OpenAudioDevice() calls
233 * always returns devices >= 2 on success. The legacy calls are good both
234 * for backwards compatibility and when you don't care about multiple,
235 * specific, or capture devices.
238 TSDL_AudioDeviceID = UInt32;
241 * Get the number of available devices exposed by the current driver.
242 * Only valid after a successfully initializing the audio subsystem.
243 * Returns -1 if an explicit list of devices can't be determined; this is
244 * not an error. For example, if SDL is set up to talk to a remote audio
245 * server, it can't list every one available on the Internet, but it will
246 * still allow a specific host to be specified to SDL_OpenAudioDevice().
248 * In many common cases, when this function returns a value <= 0, it can still
249 * successfully open the default device (NULL for first argument of
250 * SDL_OpenAudioDevice()).
252 function SDL_GetNumAudioDevices(iscapture: Integer): Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetNumAudioDevices' {$ENDIF} {$ENDIF};
255 * Get the human-readable name of a specific audio device.
256 * Must be a value between 0 and (number of audio devices-1).
257 * Only valid after a successfully initializing the audio subsystem.
258 * The values returned by this function reflect the latest call to
259 * SDL_GetNumAudioDevices(); recall that function to redetect available
262 * The string returned by this function is UTF-8 encoded, read-only, and
263 * managed internally. You are not to free it. If you need to keep the
264 * string for any length of time, you should make your own copy of it, as it
265 * will be invalid next time any of several other SDL functions is called.
267 function SDL_GetAudioDeviceName(index: Integer; iscapture: Integer): PAnsiChar cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetAudioDeviceName' {$ENDIF} {$ENDIF};
270 * Open a specific audio device. Passing in a device name of NULL requests
271 * the most reasonable default (and is equivalent to calling SDL_OpenAudio()).
273 * The device name is a UTF-8 string reported by SDL_GetAudioDeviceName(), but
274 * some drivers allow arbitrary and driver-specific strings, such as a
275 * hostname/IP address for a remote audio server, or a filename in the
278 * 0 on error, a valid device ID that is >= 2 on success.
280 * SDL_OpenAudio(), unlike this function, always acts on device ID 1.
282 function SDL_OpenAudioDevice(device: PAnsiChar;
284 desired: PSDL_AudioSpec;
285 obtained: PSDL_AudioSpec;
286 allowed_changes: Integer): TSDL_AudioDeviceID cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_OpenAudioDevice' {$ENDIF} {$ENDIF};
291 * Get the current audio state.
295 TSDL_AudioStatus = (SDL_AUDIO_STOPPED,SDL_AUDIO_PLAYING,SDL_AUDIO_PAUSED);
297 function SDL_GetAudioStatus: TSDL_AudioStatus cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetAudioStatus' {$ENDIF} {$ENDIF};
299 function SDL_GetAudioDeviceStatus(dev: TSDL_AudioDeviceID): TSDL_AudioStatus cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetAudioDeviceStatus' {$ENDIF} {$ENDIF};
303 * Pause audio functions
305 * These functions pause and unpause the audio callback processing.
306 * They should be called with a parameter of 0 after opening the audio
307 * device to start playing sound. This is so you can safely initialize
308 * data for your callback function after opening the audio device.
309 * Silence will be written to the audio device during the pause.
312 procedure SDL_PauseAudio(pause_on: Integer) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_PauseAudio' {$ENDIF} {$ENDIF};
313 procedure SDL_PauseAudioDevice(dev: TSDL_AudioDeviceID; pause_on: Integer) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_PauseAudioDevice' {$ENDIF} {$ENDIF};
314 {*Pause audio functions*}
317 * This function loads a WAVE from the data source, automatically freeing
318 * that source if freesrc is non-zero. For example, to load a WAVE file,
321 * SDL_LoadWAV_RW(SDL_RWFromFile("sample.wav", "rb"), 1, ...);
324 * If this function succeeds, it returns the given SDL_AudioSpec,
325 * filled with the audio data format of the wave data, and sets
326 * *audio_buf to a malloc()'d buffer containing the audio data,
327 * and sets *audio_len to the length of that audio buffer, in bytes.
328 * You need to free the audio buffer with SDL_FreeWAV() when you are
331 * This function returns NULL and sets the SDL error message if the
332 * wave file cannot be opened, uses an unknown data format, or is
333 * corrupt. Currently raw and MS-ADPCM WAVE files are supported.
335 function SDL_LoadWAV_RW(src: PSDL_RWops; freesrc: Integer; spec: PSDL_AudioSpec; audio_buf: PPUInt8; audio_len: PUInt32): PSDL_AudioSpec cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_LoadWAV_RW' {$ENDIF} {$ENDIF};
338 * Loads a WAV from a file.
339 * Compatibility convenience function.
342 function SDL_LoadWAV(_file: PAnsiChar; spec: PSDL_AudioSpec; audio_buf: PPUInt8; audio_len: PUInt32): PSDL_AudioSpec;
345 * This function frees data previously allocated with SDL_LoadWAV_RW()
347 procedure SDL_FreeWAV(audio_buf: PUInt8) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_FreeWAV' {$ENDIF} {$ENDIF};
350 * This function takes a source format and rate and a destination format
351 * and rate, and initializes the cvt structure with information needed
352 * by SDL_ConvertAudio() to convert a buffer of audio data from one format
355 * -1 if the format conversion is not supported, 0 if there's
356 * no conversion needed, or 1 if the audio filter is set up.
358 function SDL_BuildAudioCVT(cvt: PSDL_AudioCVT;
359 src_format: TSDL_AudioFormat;
362 dst_format: TSDL_AudioFormat;
364 dst_rate: Integer): Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_BuildAudioCVT' {$ENDIF} {$ENDIF};
367 * Once you have initialized the cvt structure using SDL_BuildAudioCVT(),
368 * created an audio buffer cvt->buf, and filled it with cvt->len bytes of
369 * audio data in the source format, this function will convert it in-place
370 * to the desired format.
372 * The data conversion may expand the size of the audio data, so the buffer
373 * cvt->buf should be allocated after the cvt structure is initialized by
374 * SDL_BuildAudioCVT(), and should be cvt->len*cvt->len_mult bytes long.
376 function SDL_ConvertAudio(cvt: PSDL_AudioCVT): Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_ConvertAudio' {$ENDIF} {$ENDIF};
379 SDL_MIX_MAXVOLUME = 128;
382 * This takes two audio buffers of the playing audio format and mixes
383 * them, performing addition, volume adjustment, and overflow clipping.
384 * The volume ranges from 0 - 128, and should be set to ::SDL_MIX_MAXVOLUME
385 * for full audio volume. Note this does not change hardware volume.
386 * This is provided for convenience -- you can mix your own audio data.
388 procedure SDL_MixAudio(dst: PUInt8; src: PUInt8; len: UInt32; volume: Integer) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_MixAudio' {$ENDIF} {$ENDIF};
391 * This works like SDL_MixAudio(), but you specify the audio format instead of
392 * using the format of audio device 1. Thus it can be used when no audio
393 * device is open at all.
395 procedure SDL_MixAudioFormat(dst: PUInt8; src: PUInt8; format: TSDL_AudioFormat; len: UInt32; volume: Integer) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_MixAudioFormat' {$ENDIF} {$ENDIF};
398 * Audio lock functions
400 * The lock manipulated by these functions protects the callback function.
401 * During a SDL_LockAudio()/SDL_UnlockAudio() pair, you can be guaranteed that
402 * the callback function is not running. Do not call these from the callback
403 * function or you will cause deadlock.
406 procedure SDL_LockAudio cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_LockAudio' {$ENDIF} {$ENDIF};
407 procedure SDL_LockAudioDevice(dev: TSDL_AudioDeviceID) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_LockAudioDevice' {$ENDIF} {$ENDIF};
408 procedure SDL_UnlockAudio cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_Unlock' {$ENDIF} {$ENDIF};
409 procedure SDL_UnlockAudioDevice(dev: TSDL_AudioDeviceID) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_UnlockAudioDevice' {$ENDIF} {$ENDIF};
410 {*Audio lock functions*}
413 * This function shuts down audio processing and closes the audio device.
415 procedure SDL_CloseAudio cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_CloseAudio' {$ENDIF} {$ENDIF};
416 procedure SDL_CloseAudioDevice(dev: TSDL_AudioDeviceID) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_CloseAudioDevice' {$ENDIF} {$ENDIF};
419 * 1 if audio device is still functioning, zero if not, -1 on error.
421 function SDL_AudioDeviceConnected(dev: TSDL_AudioDeviceID): Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_AudioDeviceConnected' {$ENDIF} {$ENDIF};