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