SDL Mixer X

SDL mixer version 2.0 - part of Simple DirectMedia Layer (SDL) library which giving complex audio functions, mainly for sound mixing.

This part appending to SDL additional functions which giving able to play more sound and music formats.

SDL Mixer used in the PGE Project as part of default audio engine and also included by Wohlstand and Kevsoft into the LunaDLL to replace the MCI audio engine to take able play more music formats inside SMBX.

Music Formats

SDL_Mixer have support of playback for next formats which can be played in the music stream:

Standard music formats

WAV Microsoft PCM, Uncompressed audio
VOC Creative Labs Audio File
MP3 MPEG-2 Layer 3, Lossy data compressed audio (Will play MP3 correctly only if it was built with using of libMAD library)
OGG OGG Vorbis, Lossy data compressed audio
FLAC Free Lossless Audio Codec, Loss-less compressed
MIDI Music Instrument Digital Interface, commands list
SPC SNES music file. Is not supported in official builds of SDL2_mixer but support was implemented in the modified version of this library which usually includes with LunaLUA and with PGE Project package.

Tracker music formats

669 Composer 669, Unis 669
AMF DSMI Advanced Module Format
AMF ASYLUM Music Format V1.0
APUN APlayer
DSM DSIK internal format
FAR Farandole Composer
GDM General DigiMusic
IT Impulse Tracker
IMF Imago Orpheus
MOD 15 and 31 instruments
MED OctaMED
MTM MultiTracker Module editor
OKT Amiga Oktalyzer
S3M Scream Tracker 3
STM Scream Tracker
STX Scream Tracker Music Interface Kit
ULT UltraTracker
UNI MikMod
XM FastTracker 2

SFX Formats

SDL_Mixer have a support of playback for next sound effects which can be preloaded into memory played in difference channels with mixing:

WAV Microsoft PCM, Uncompressed audio
VOC Creative Labs Audio File
OGG OGG Vorbis, Lossy data compressed audio
FLAC Free Lossless Audio Codec, Loss-less compressed

Issues

Here is a list of known issues of SDL Mixer v2.0 library:

• [Fixed] Fade-IN in some cases is not working correctly, but Fade-Out working perfectly
• Official build of SMPEG library can't play MP3 on Windows and Linux system, but on some Mac OS computers it working fine. To fix this issue need a rebuild of SDL_mixer library with using of libMAD library.
• Wrongly working real-time re-sampling of music files to get fit into united audio stream. For example, musics with sample rate less than sample rate of stream will cause soft breakthroughs of playback. But if musics have a sample rate more than sample rate of stream will cause noisy playback. (for example, musics with 32000 Hz will be played with breakthroughs in the 44100 Hz stream, but in the same stream musics with 48000 Hz will be played noisy and buggy). To escape this issue you should re-sample your music file manually to get correct playback in the defined sample rate of stream.

Links

• Official documentation of SDL Mixer library API
• Source code of modified SDL Mixer version (with SPC and custom MP3 down-sampling support. Building with qmake && make from Qt 5).