SDL  2.0
SDL_audio_c.h
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2017 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 
22 #ifndef SDL_audio_c_h_
23 #define SDL_audio_c_h_
24 
25 #include "../SDL_internal.h"
26 
27 #ifndef DEBUG_CONVERT
28 #define DEBUG_CONVERT 0
29 #endif
30 
31 #if DEBUG_CONVERT
32 #define LOG_DEBUG_CONVERT(from, to) fprintf(stderr, "Converting %s to %s.\n", from, to);
33 #else
34 #define LOG_DEBUG_CONVERT(from, to)
35 #endif
36 
37 /* Functions and variables exported from SDL_audio.c for SDL_sysaudio.c */
38 
39 #ifdef HAVE_LIBSAMPLERATE_H
40 #include "samplerate.h"
41 extern SDL_bool SRC_available;
42 extern int SRC_converter;
43 extern SRC_STATE* (*SRC_src_new)(int converter_type, int channels, int *error);
44 extern int (*SRC_src_process)(SRC_STATE *state, SRC_DATA *data);
45 extern int (*SRC_src_reset)(SRC_STATE *state);
46 extern SRC_STATE* (*SRC_src_delete)(SRC_STATE *state);
47 extern const char* (*SRC_src_strerror)(int error);
48 #endif
49 
50 /* Functions to get a list of "close" audio formats */
53 
54 /* Function to calculate the size and silence for a SDL_AudioSpec */
56 
57 /* Choose the audio filter functions below */
58 extern void SDL_ChooseAudioConverters(void);
59 
60 /* These pointers get set during SDL_ChooseAudioConverters() to various SIMD implementations. */
71 
72 /* You need to call SDL_PrepareResampleFilter() before using the internal resampler.
73  SDL_AudioQuit() calls SDL_FreeResamplerFilter(), you should never call it yourself. */
74 extern int SDL_PrepareResampleFilter(void);
75 extern void SDL_FreeResampleFilter(void);
76 
77 
78 /* SDL_AudioStream is a new audio conversion interface. It
79  might eventually become a public API.
80  The benefits vs SDL_AudioCVT:
81  - it can handle resampling data in chunks without generating
82  artifacts, when it doesn't have the complete buffer available.
83  - it can handle incoming data in any variable size.
84  - You push data as you have it, and pull it when you need it
85 
86  (Note that currently this converts as data is put into the stream, so
87  you need to push more than a handful of bytes if you want decent
88  resampling. This can be changed later.)
89  */
90 
91 /* this is opaque to the outside world. */
92 typedef struct SDL_AudioStream SDL_AudioStream;
93 
94 /* create a new stream */
96  const Uint8 src_channels,
97  const int src_rate,
99  const Uint8 dst_channels,
100  const int dst_rate);
101 
102 /* add data to be converted/resampled to the stream */
103 extern int SDL_AudioStreamPut(SDL_AudioStream *stream, const void *buf, const Uint32 len);
104 
105 /* get converted/resampled data from the stream */
106 extern int SDL_AudioStreamGet(SDL_AudioStream *stream, void *buf, const Uint32 len);
107 
108 /* clear any pending data in the stream without converting it. */
110 
111 /* number of converted/resampled bytes available */
113 
114 /* dispose of a stream */
116 
117 #endif /* SDL_audio_c_h_ */
118 
119 /* vi: set ts=4 sw=4 expandtab: */
SDL_AudioStream * SDL_NewAudioStream(const SDL_AudioFormat src_format, const Uint8 src_channels, const int src_rate, const SDL_AudioFormat dst_format, const Uint8 dst_channels, const int dst_rate)
void SDL_FreeAudioStream(SDL_AudioStream *stream)
SDL_AudioFormat SDL_FirstAudioFormat(SDL_AudioFormat format)
Definition: SDL_audio.c:1577
void SDL_ChooseAudioConverters(void)
SDL_AudioFormat src_format
SDL_AudioFilter SDL_Convert_F32_to_S32
struct xkb_state * state
int SDL_AudioStreamGet(SDL_AudioStream *stream, void *buf, const Uint32 len)
SDL_AudioFilter SDL_Convert_S16_to_F32
SDL_AudioFilter SDL_Convert_U16_to_F32
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: SDL_opengl.h:1974
Uint16 SDL_AudioFormat
Audio format flags.
Definition: SDL_audio.h:64
SDL_AudioFormat SDL_NextAudioFormat(void)
Definition: SDL_audio.c:1589
uint32_t Uint32
Definition: SDL_stdinc.h:181
GLenum GLsizei len
GLint GLint GLsizei GLsizei GLsizei GLint GLenum format
Definition: SDL_opengl.h:1572
SDL_AudioSpec spec
Definition: loopwave.c:31
SDL_AudioFormat dst_format
GLuint GLuint stream
uint8_t Uint8
Definition: SDL_stdinc.h:157
void SDL_FreeResampleFilter(void)
Definition: SDL_audiocvt.c:459
int SDL_AudioStreamPut(SDL_AudioStream *stream, const void *buf, const Uint32 len)
SDL_AudioFilter SDL_Convert_F32_to_S8
void SDL_CalculateAudioSpec(SDL_AudioSpec *spec)
Definition: SDL_audio.c:1598
GLenum GLuint GLenum GLsizei const GLchar * buf
SDL_AudioFilter SDL_Convert_F32_to_U8
SDL_AudioFilter SDL_Convert_S8_to_F32
SDL_AudioFilter SDL_Convert_U8_to_F32
SDL_bool
Definition: SDL_stdinc.h:139
int SDL_AudioStreamAvailable(SDL_AudioStream *stream)
SDL_AudioFilter SDL_Convert_F32_to_U16
void(* SDL_AudioFilter)(struct SDL_AudioCVT *cvt, SDL_AudioFormat format)
Definition: SDL_audio.h:183
int SDL_PrepareResampleFilter(void)
Definition: SDL_audiocvt.c:430
void SDL_AudioStreamClear(SDL_AudioStream *stream)
SDL_AudioFilter SDL_Convert_S32_to_F32
SDL_AudioFilter SDL_Convert_F32_to_S16