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1 | .TH "SDL_AudioSpec" "3" "Tue 11 Sep 2001, 22:58" "SDL" "SDL API Reference" |
2 | .SH "NAME" |
3 | SDL_AudioSpec \- Audio Specification Structure |
4 | .SH "STRUCTURE DEFINITION" |
5 | .PP |
6 | .nf |
7 | \f(CWtypedef struct{ |
8 | int freq; |
9 | Uint16 format; |
10 | Uint8 channels; |
11 | Uint8 silence; |
12 | Uint16 samples; |
13 | Uint32 size; |
14 | void (*callback)(void *userdata, Uint8 *stream, int len); |
15 | void *userdata; |
16 | } SDL_AudioSpec;\fR |
17 | .fi |
18 | .PP |
19 | .SH "STRUCTURE DATA" |
20 | .TP 20 |
21 | \fBfreq\fR |
22 | Audio frequency in samples per second |
23 | .TP 20 |
24 | \fBformat\fR |
25 | Audio data format |
26 | .TP 20 |
27 | \fBchannels\fR |
28 | Number of channels: 1 mono, 2 stereo |
29 | .TP 20 |
30 | \fBsilence\fR |
31 | Audio buffer silence value (calculated) |
32 | .TP 20 |
33 | \fBsamples\fR |
34 | Audio buffer size in samples |
35 | .TP 20 |
36 | \fBsize\fR |
37 | Audio buffer size in bytes (calculated) |
38 | .TP 20 |
39 | \fBcallback(\&.\&.)\fR |
40 | Callback function for filling the audio buffer |
41 | .TP 20 |
42 | \fBuserdata\fR |
43 | Pointer the user data which is passed to the callback function |
44 | .SH "DESCRIPTION" |
45 | .PP |
46 | The \fBSDL_AudioSpec\fR structure is used to describe the format of some audio data\&. This structure is used by \fI\fBSDL_OpenAudio\fP\fR and \fI\fBSDL_LoadWAV\fP\fR\&. While all fields are used by \fBSDL_OpenAudio\fP only \fBfreq\fR, \fBformat\fR, \fBsamples\fR and \fBchannels\fR are used by \fBSDL_LoadWAV\fP\&. We will detail these common members here\&. |
47 | .TP 20 |
48 | \fBfreq\fR |
49 | The number of samples sent to the sound device every second\&. Common values are 11025, 22050 and 44100\&. The higher the better\&. |
50 | .TP 20 |
51 | \fBformat\fR |
52 | Specifies the size and type of each sample element |
53 | .IP "\fBAUDIO_U8\fP" 10Unsigned 8-bit samples |
54 | .IP "\fBAUDIO_S8\fP" 10Signed 8-bit samples |
55 | .IP "\fBAUDIO_U16\fP or \fBAUDIO_U16LSB\fP" 10Unsigned 16-bit little-endian samples |
56 | .IP "\fBAUDIO_S16\fP or \fBAUDIO_S16LSB\fP" 10Signed 16-bit little-endian samples |
57 | .IP "\fBAUDIO_U16MSB\fP" 10Unsigned 16-bit big-endian samples |
58 | .IP "\fBAUDIO_S16MSB\fP" 10Signed 16-bit big-endian samples |
59 | .IP "\fBAUDIO_U16SYS\fP" 10Either \fBAUDIO_U16LSB\fP or \fBAUDIO_U16MSB\fP depending on you systems endianness |
60 | .IP "\fBAUDIO_S16SYS\fP" 10Either \fBAUDIO_S16LSB\fP or \fBAUDIO_S16MSB\fP depending on you systems endianness |
61 | .TP 20 |
62 | \fBchannels\fR |
63 | The number of seperate sound channels\&. 1 is mono (single channel), 2 is stereo (dual channel)\&. |
64 | .TP 20 |
65 | \fBsamples\fR |
66 | When used with \fI\fBSDL_OpenAudio\fP\fR this refers to the size of the audio buffer in samples\&. A sample a chunk of audio data of the size specified in \fBformat\fR mulitplied by the number of channels\&. When the \fBSDL_AudioSpec\fR is used with \fI\fBSDL_LoadWAV\fP\fR \fBsamples\fR is set to 4096\&. |
67 | .SH "SEE ALSO" |
68 | .PP |
69 | \fI\fBSDL_OpenAudio\fP\fR, \fI\fBSDL_LoadWAV\fP\fR |
70 | .\" created by instant / docbook-to-man, Tue 11 Sep 2001, 22:58 |