| <HTML |
| ><HEAD |
| ><TITLE |
| >SDL_AudioSpec</TITLE |
| ><META |
| NAME="GENERATOR" |
| CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ |
| "><LINK |
| REL="HOME" |
| TITLE="SDL Library Documentation" |
| HREF="index.html"><LINK |
| REL="UP" |
| TITLE="Audio" |
| HREF="audio.html"><LINK |
| REL="PREVIOUS" |
| TITLE="Audio" |
| HREF="audio.html"><LINK |
| REL="NEXT" |
| TITLE="SDL_OpenAudio" |
| HREF="sdlopenaudio.html"></HEAD |
| ><BODY |
| CLASS="REFENTRY" |
| BGCOLOR="#FFF8DC" |
| TEXT="#000000" |
| LINK="#0000ee" |
| VLINK="#551a8b" |
| ALINK="#ff0000" |
| ><DIV |
| CLASS="NAVHEADER" |
| ><TABLE |
| SUMMARY="Header navigation table" |
| WIDTH="100%" |
| BORDER="0" |
| CELLPADDING="0" |
| CELLSPACING="0" |
| ><TR |
| ><TH |
| COLSPAN="3" |
| ALIGN="center" |
| >SDL Library Documentation</TH |
| ></TR |
| ><TR |
| ><TD |
| WIDTH="10%" |
| ALIGN="left" |
| VALIGN="bottom" |
| ><A |
| HREF="audio.html" |
| ACCESSKEY="P" |
| >Prev</A |
| ></TD |
| ><TD |
| WIDTH="80%" |
| ALIGN="center" |
| VALIGN="bottom" |
| ></TD |
| ><TD |
| WIDTH="10%" |
| ALIGN="right" |
| VALIGN="bottom" |
| ><A |
| HREF="sdlopenaudio.html" |
| ACCESSKEY="N" |
| >Next</A |
| ></TD |
| ></TR |
| ></TABLE |
| ><HR |
| ALIGN="LEFT" |
| WIDTH="100%"></DIV |
| ><H1 |
| ><A |
| NAME="SDLAUDIOSPEC" |
| ></A |
| >SDL_AudioSpec</H1 |
| ><DIV |
| CLASS="REFNAMEDIV" |
| ><A |
| NAME="AEN6507" |
| ></A |
| ><H2 |
| >Name</H2 |
| >SDL_AudioSpec -- Audio Specification Structure</DIV |
| ><DIV |
| CLASS="REFSECT1" |
| ><A |
| NAME="AEN6510" |
| ></A |
| ><H2 |
| >Structure Definition</H2 |
| ><PRE |
| CLASS="PROGRAMLISTING" |
| >typedef struct{ |
| int freq; |
| Uint16 format; |
| Uint8 channels; |
| Uint8 silence; |
| Uint16 samples; |
| Uint32 size; |
| void (*callback)(void *userdata, Uint8 *stream, int len); |
| void *userdata; |
| } SDL_AudioSpec;</PRE |
| ></DIV |
| ><DIV |
| CLASS="REFSECT1" |
| ><A |
| NAME="AEN6513" |
| ></A |
| ><H2 |
| >Structure Data</H2 |
| ><DIV |
| CLASS="INFORMALTABLE" |
| ><A |
| NAME="AEN6515" |
| ></A |
| ><P |
| ></P |
| ><TABLE |
| BORDER="0" |
| CLASS="CALSTABLE" |
| ><TBODY |
| ><TR |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >freq</I |
| ></TT |
| ></TD |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| >Audio frequency in samples per second</TD |
| ></TR |
| ><TR |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >format</I |
| ></TT |
| ></TD |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| >Audio data format</TD |
| ></TR |
| ><TR |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >channels</I |
| ></TT |
| ></TD |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| >Number of channels: 1 mono, 2 stereo</TD |
| ></TR |
| ><TR |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >silence</I |
| ></TT |
| ></TD |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| >Audio buffer silence value (calculated)</TD |
| ></TR |
| ><TR |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >samples</I |
| ></TT |
| ></TD |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| >Audio buffer size in samples</TD |
| ></TR |
| ><TR |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >size</I |
| ></TT |
| ></TD |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| >Audio buffer size in bytes (calculated)</TD |
| ></TR |
| ><TR |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >callback(..)</I |
| ></TT |
| ></TD |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| >Callback function for filling the audio buffer</TD |
| ></TR |
| ><TR |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >userdata</I |
| ></TT |
| ></TD |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| >Pointer the user data which is passed to the callback function</TD |
| ></TR |
| ></TBODY |
| ></TABLE |
| ><P |
| ></P |
| ></DIV |
| ></DIV |
| ><DIV |
| CLASS="REFSECT1" |
| ><A |
| NAME="AEN6550" |
| ></A |
| ><H2 |
| >Description</H2 |
| ><P |
| >The <SPAN |
| CLASS="STRUCTNAME" |
| >SDL_AudioSpec</SPAN |
| > structure is used to describe the format of some audio data. This structure is used by <A |
| HREF="sdlopenaudio.html" |
| ><TT |
| CLASS="FUNCTION" |
| >SDL_OpenAudio</TT |
| ></A |
| > and <A |
| HREF="sdlloadwav.html" |
| ><TT |
| CLASS="FUNCTION" |
| >SDL_LoadWAV</TT |
| ></A |
| >. While all fields are used by <TT |
| CLASS="FUNCTION" |
| >SDL_OpenAudio</TT |
| > only <TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >freq</I |
| ></TT |
| >, <TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >format</I |
| ></TT |
| >, <TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >samples</I |
| ></TT |
| > and <TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >channels</I |
| ></TT |
| > are used by <TT |
| CLASS="FUNCTION" |
| >SDL_LoadWAV</TT |
| >. We will detail these common members here.</P |
| ><DIV |
| CLASS="INFORMALTABLE" |
| ><A |
| NAME="AEN6564" |
| ></A |
| ><P |
| ></P |
| ><TABLE |
| BORDER="0" |
| CLASS="CALSTABLE" |
| ><TBODY |
| ><TR |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >freq</I |
| ></TT |
| ></TD |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><P |
| >The number of samples sent to the sound device every second. Common values are 11025, 22050 and 44100. The higher the better.</P |
| ></TD |
| ></TR |
| ><TR |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >format</I |
| ></TT |
| ></TD |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><P |
| >Specifies the size and type of each sample element |
| <P |
| ></P |
| ><DIV |
| CLASS="VARIABLELIST" |
| ><DL |
| ><DT |
| ><TT |
| CLASS="LITERAL" |
| >AUDIO_U8</TT |
| ></DT |
| ><DD |
| ><P |
| >Unsigned 8-bit samples</P |
| ></DD |
| ><DT |
| ><TT |
| CLASS="LITERAL" |
| >AUDIO_S8</TT |
| ></DT |
| ><DD |
| ><P |
| >Signed 8-bit samples</P |
| ></DD |
| ><DT |
| ><TT |
| CLASS="LITERAL" |
| >AUDIO_U16</TT |
| > or <TT |
| CLASS="LITERAL" |
| >AUDIO_U16LSB</TT |
| ></DT |
| ><DD |
| ><P |
| >Unsigned 16-bit little-endian samples</P |
| ></DD |
| ><DT |
| ><TT |
| CLASS="LITERAL" |
| >AUDIO_S16</TT |
| > or <TT |
| CLASS="LITERAL" |
| >AUDIO_S16LSB</TT |
| ></DT |
| ><DD |
| ><P |
| >Signed 16-bit little-endian samples</P |
| ></DD |
| ><DT |
| ><TT |
| CLASS="LITERAL" |
| >AUDIO_U16MSB</TT |
| ></DT |
| ><DD |
| ><P |
| >Unsigned 16-bit big-endian samples</P |
| ></DD |
| ><DT |
| ><TT |
| CLASS="LITERAL" |
| >AUDIO_S16MSB</TT |
| ></DT |
| ><DD |
| ><P |
| >Signed 16-bit big-endian samples</P |
| ></DD |
| ><DT |
| ><TT |
| CLASS="LITERAL" |
| >AUDIO_U16SYS</TT |
| ></DT |
| ><DD |
| ><P |
| >Either <TT |
| CLASS="LITERAL" |
| >AUDIO_U16LSB</TT |
| > or <TT |
| CLASS="LITERAL" |
| >AUDIO_U16MSB</TT |
| > depending on you systems endianness</P |
| ></DD |
| ><DT |
| ><TT |
| CLASS="LITERAL" |
| >AUDIO_S16SYS</TT |
| ></DT |
| ><DD |
| ><P |
| >Either <TT |
| CLASS="LITERAL" |
| >AUDIO_S16LSB</TT |
| > or <TT |
| CLASS="LITERAL" |
| >AUDIO_S16MSB</TT |
| > depending on you systems endianness</P |
| ></DD |
| ></DL |
| ></DIV |
| ></P |
| ></TD |
| ></TR |
| ><TR |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >channels</I |
| ></TT |
| ></TD |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| >The number of seperate sound channels. 1 is mono (single channel), 2 is stereo (dual channel).</TD |
| ></TR |
| ><TR |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| ><TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >samples</I |
| ></TT |
| ></TD |
| ><TD |
| ALIGN="LEFT" |
| VALIGN="TOP" |
| >When used with <A |
| HREF="sdlopenaudio.html" |
| ><TT |
| CLASS="FUNCTION" |
| >SDL_OpenAudio</TT |
| ></A |
| > this refers to the size of the audio buffer in samples. A sample a chunk of audio data of the size specified in <TT |
| CLASS="PARAMETER" |
| ><I |
| >format</I |
| ></TT |
| > mulitplied by the number of channels. When the <SPAN |
| CLASS="STRUCTNAME" |
| >SDL_AudioSpec</SPAN |
| > is used with <A |
| HREF="sdlloadwav.html" |
| ><TT |
| CLASS="FUNCTION" |
| >SDL_LoadWAV</TT |
| ></A |
| > <TT |
| CLASS="STRUCTFIELD" |
| ><I |
| >samples</I |
| ></TT |
| > is set to 4096.</TD |
| ></TR |
| ></TBODY |
| ></TABLE |
| ><P |
| ></P |
| ></DIV |
| ></DIV |
| ><DIV |
| CLASS="REFSECT1" |
| ><A |
| NAME="AEN6639" |
| ></A |
| ><H2 |
| >See Also</H2 |
| ><P |
| ><A |
| HREF="sdlopenaudio.html" |
| ><TT |
| CLASS="FUNCTION" |
| >SDL_OpenAudio</TT |
| ></A |
| >, |
| <A |
| HREF="sdlloadwav.html" |
| ><TT |
| CLASS="FUNCTION" |
| >SDL_LoadWAV</TT |
| ></A |
| ></P |
| ></DIV |
| ><DIV |
| CLASS="NAVFOOTER" |
| ><HR |
| ALIGN="LEFT" |
| WIDTH="100%"><TABLE |
| SUMMARY="Footer navigation table" |
| WIDTH="100%" |
| BORDER="0" |
| CELLPADDING="0" |
| CELLSPACING="0" |
| ><TR |
| ><TD |
| WIDTH="33%" |
| ALIGN="left" |
| VALIGN="top" |
| ><A |
| HREF="audio.html" |
| ACCESSKEY="P" |
| >Prev</A |
| ></TD |
| ><TD |
| WIDTH="34%" |
| ALIGN="center" |
| VALIGN="top" |
| ><A |
| HREF="index.html" |
| ACCESSKEY="H" |
| >Home</A |
| ></TD |
| ><TD |
| WIDTH="33%" |
| ALIGN="right" |
| VALIGN="top" |
| ><A |
| HREF="sdlopenaudio.html" |
| ACCESSKEY="N" |
| >Next</A |
| ></TD |
| ></TR |
| ><TR |
| ><TD |
| WIDTH="33%" |
| ALIGN="left" |
| VALIGN="top" |
| >Audio</TD |
| ><TD |
| WIDTH="34%" |
| ALIGN="center" |
| VALIGN="top" |
| ><A |
| HREF="audio.html" |
| ACCESSKEY="U" |
| >Up</A |
| ></TD |
| ><TD |
| WIDTH="33%" |
| ALIGN="right" |
| VALIGN="top" |
| >SDL_OpenAudio</TD |
| ></TR |
| ></TABLE |
| ></DIV |
| ></BODY |
| ></HTML |
| > |
