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view docs/html/cdrom.html @ 1260:80f8c94b5199
Date: 10 Jun 2003 15:30:59 -0400
From: Mike Shal
Subject: [SDL] Bug in SDL_wave.c?
Hey everyone, I'm not sure if this is a bug in SDL, or if I just have
incorrect WAV files. The problem I'm having is loading multiple
concatenated WAVs from SDL_LoadWAV_RW. Some WAV files put comments at
the end of the file (which may be bad form), and SDL doesn't skip past
them when reading from the RWops. So the next WAV I try to load will
start at the comment section of the previous WAV, which obviously
doesn't work. If anyone else is having this problem, one quick fix you
can do is run sox on the bad WAVs, which strips out all of the comment
sections.
Eg:
$ sox sound.wav tmp.wav
$ mv -f tmp.wav sound.wav
The other fix is to patch SDL_wave.c, which is included with this email.
(Assuming I made the patch correctly :). All it does is calculate how
much remaining space there is in the WAV file after the data chunk, and
does SDL_RWseek to skip it. I don't think it should interfere with
anything else, but if someone could check it that would be nice :). If
the bug is really with SDL and not with my WAVs, can someone work this
into the next version of SDL? Thanks,
-Mike Shal
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Tue, 24 Jan 2006 07:20:18 +0000 |
parents | 355632dca928 |
children |
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<HTML ><HEAD ><TITLE >CD-ROM</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="SDL Reference" HREF="reference.html"><LINK REL="PREVIOUS" TITLE="SDL_CloseAudio" HREF="sdlcloseaudio.html"><LINK REL="NEXT" TITLE="SDL_CDNumDrives" HREF="sdlcdnumdrives.html"><META NAME="KEYWORD" CONTENT="cdrom"><META NAME="KEYWORD" CONTENT="function"></HEAD ><BODY CLASS="CHAPTER" 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="sdlcloseaudio.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlcdnumdrives.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="CHAPTER" ><H1 ><A NAME="CDROM" ></A >Chapter 11. CD-ROM</H1 ><DIV CLASS="TOC" ><DL ><DT ><B >Table of Contents</B ></DT ><DT ><A HREF="sdlcdnumdrives.html" >SDL_CDNumDrives</A > -- Returns the number of CD-ROM drives on the system.</DT ><DT ><A HREF="sdlcdname.html" >SDL_CDName</A > -- Returns a human-readable, system-dependent identifier for the CD-ROM.</DT ><DT ><A HREF="sdlcdopen.html" >SDL_CDOpen</A > -- Opens a CD-ROM drive for access.</DT ><DT ><A HREF="sdlcdstatus.html" >SDL_CDStatus</A > -- Returns the current status of the given drive.</DT ><DT ><A HREF="sdlcdplay.html" >SDL_CDPlay</A > -- Play a CD</DT ><DT ><A HREF="sdlcdplaytracks.html" >SDL_CDPlayTracks</A > -- Play the given CD track(s)</DT ><DT ><A HREF="sdlcdpause.html" >SDL_CDPause</A > -- Pauses a CDROM</DT ><DT ><A HREF="sdlcdresume.html" >SDL_CDResume</A > -- Resumes a CDROM</DT ><DT ><A HREF="sdlcdstop.html" >SDL_CDStop</A > -- Stops a CDROM</DT ><DT ><A HREF="sdlcdeject.html" >SDL_CDEject</A > -- Ejects a CDROM</DT ><DT ><A HREF="sdlcdclose.html" >SDL_CDClose</A > -- Closes a SDL_CD handle</DT ><DT ><A HREF="sdlcd.html" >SDL_CD</A > -- CDROM Drive Information</DT ><DT ><A HREF="sdlcdtrack.html" >SDL_CDtrack</A > -- CD Track Information Structure</DT ></DL ></DIV ><P >SDL supports audio control of up to 32 local CD-ROM drives at once.</P ><P >You use this API to perform all the basic functions of a CD player, including listing the tracks, playing, stopping, and ejecting the CD-ROM. (Currently, multi-changer CD drives are not supported.)</P ><P >Before you call any of the SDL CD-ROM functions, you must first call "<TT CLASS="FUNCTION" >SDL_Init(SDL_INIT_CDROM)</TT >", which scans the system for CD-ROM drives, and sets the program up for audio control. Check the return code, which should be <SPAN CLASS="RETURNVALUE" >0</SPAN >, to see if there were any errors in starting up.</P ><P >After you have initialized the library, you can find out how many drives are available using the <TT CLASS="FUNCTION" >SDL_CDNumDrives()</TT > function. The first drive listed is the system default CD-ROM drive. After you have chosen a drive, and have opened it with <TT CLASS="FUNCTION" >SDL_CDOpen()</TT >, you can check the status and start playing if there's a CD in the drive.</P ><P >A CD-ROM is organized into one or more tracks, each consisting of a certain number of "frames". Each frame is ~2K in size, and at normal playing speed, a CD plays 75 frames per second. SDL works with the number of frames on a CD, but this can easily be converted to the more familiar minutes/seconds format by using the <TT CLASS="FUNCTION" >FRAMES_TO_MSF()</TT > macro.</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="sdlcloseaudio.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="sdlcdnumdrives.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_CloseAudio</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="reference.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_CDNumDrives</TD ></TR ></TABLE ></DIV ></BODY ></HTML >