Mercurial > SDL_sound_CoreAudio
view playsound/physfsrwops.h @ 474:c66080364dff
Most decoders now report total sample play time, now. Technically, this
breaks binary compatibility with the 1.0 branch, since it extends the
Sound_Sample struct, but most (all?) programs are just passing pointers
allocated by SDL_sound around, and might be okay.
Source-level compatibility is not broken...yet! :)
--ryan.
-------- Original Message --------
Subject: SDL_sound patch: Finding total length of time of sound file.
Date: Sun, 26 Jan 2003 09:31:17 -0800 (PST)
Hi Ryan,
I am working with Eric Wing and helping him modify
SDL_sound. AS part of our efforts in improving and
enhancing SDL_sound, we like to submit this patch. We
modified the codecs to find the total time of a sound
file. Below is the explanation of the patch. The
patch is appended as an attachment to this email.
* MOTIVATION:
We needed the ability to get the total play time of a
sample (And we noticed that we're not the only ones).
Since SDL_sound blocks direct access to the specific
decoders, there is no way for a user to know this
information short of decoding the whole thing.
Because of this, we believe this will be a useful
addition, even though the accuracy may not be perfect
(subject to each decoder) or the information may not
always be available.
* CONTRIBUTORS:
Wesley Leong (modified the majority of the codecs and
verified the results)
Eric Wing (showed everyone how to do modify codec,
modified mikmod)
Wang Lam (modified a handful of codecs, researched
into specs and int overflow)
Ahilan Anantha (modified a few codecs and helped with
integer math)
* GENERAL ISSUES:
We chose the value to be milliseconds as an Sint32.
Milliseconds because that's what Sound_Seek takes as a
parameter and -1 to allow for instances/codecs where
the value could not be determined. We are
not sure if this is the final convention you want, so
we are willing to work with you on this.
We also expect the total_time field to be set on open
and never again modified by SDL_sound. Users may
access it directly much like the sample buffer and
buffer_size. We thought about recomputing the time
on DecodeAll, but since users may seek or decode small
chunks first, not all the data may be there. So this
is better done by the user. This may be good
information to document.
Currently, all the main codecs are implemented except
for QuickTime.
author | Ryan C. Gordon <icculus@icculus.org> |
---|---|
date | Sat, 08 May 2004 08:19:50 +0000 |
parents | d8c0315deba9 |
children | 50bb9a6cebfe |
line wrap: on
line source
/* * This code provides a glue layer between PhysicsFS and Simple Directmedia * Layer's (SDL) RWops i/o abstraction. * * License: this code is public domain. I make no warranty that it is useful, * correct, harmless, or environmentally safe. * * This particular file may be used however you like, including copying it * verbatim into a closed-source project, exploiting it commercially, and * removing any trace of my name from the source (although I hope you won't * do that). I welcome enhancements and corrections to this file, but I do * not require you to send me patches if you make changes. * * Unless otherwise stated, the rest of PhysicsFS falls under the GNU Lesser * General Public License: http://www.gnu.org/licenses/lgpl.txt * * SDL falls under the LGPL, too. You can get SDL at http://www.libsdl.org/ * * This file was written by Ryan C. Gordon. (icculus@clutteredmind.org). */ #ifndef _INCLUDE_PHYSFSRWOPS_H_ #define _INCLUDE_PHYSFSRWOPS_H_ #include "physfs.h" #include "SDL.h" #ifdef __cplusplus extern "C" { #endif /** * Open a platform-independent filename for reading, and make it accessible * via an SDL_RWops structure. The file will be closed in PhysicsFS when the * RWops is closed. PhysicsFS should be configured to your liking before * opening files through this method. * * @param filename File to open in platform-independent notation. * @return A valid SDL_RWops structure on success, NULL on error. Specifics * of the error can be gleaned from PHYSFS_getLastError(). */ __EXPORT__ SDL_RWops *PHYSFSRWOPS_openRead(const char *fname); /** * Open a platform-independent filename for writing, and make it accessible * via an SDL_RWops structure. The file will be closed in PhysicsFS when the * RWops is closed. PhysicsFS should be configured to your liking before * opening files through this method. * * @param filename File to open in platform-independent notation. * @return A valid SDL_RWops structure on success, NULL on error. Specifics * of the error can be gleaned from PHYSFS_getLastError(). */ __EXPORT__ SDL_RWops *PHYSFSRWOPS_openWrite(const char *fname); /** * Open a platform-independent filename for appending, and make it accessible * via an SDL_RWops structure. The file will be closed in PhysicsFS when the * RWops is closed. PhysicsFS should be configured to your liking before * opening files through this method. * * @param filename File to open in platform-independent notation. * @return A valid SDL_RWops structure on success, NULL on error. Specifics * of the error can be gleaned from PHYSFS_getLastError(). */ __EXPORT__ SDL_RWops *PHYSFSRWOPS_openAppend(const char *fname); /** * Make a SDL_RWops from an existing PhysicsFS file handle. You should * dispose of any references to the handle after successful creation of * the RWops. The actual PhysicsFS handle will be destroyed when the * RWops is closed. * * @param handle a valid PhysicsFS file handle. * @return A valid SDL_RWops structure on success, NULL on error. Specifics * of the error can be gleaned from PHYSFS_getLastError(). */ __EXPORT__ SDL_RWops *PHYSFSRWOPS_makeRWops(PHYSFS_file *handle); #ifdef __cplusplus } #endif #endif /* include-once blocker */ /* end of physfsrwops.h ... */