How to Play Multiple MP3 files simultaneously in SDL?

Question

I want to play multiple MP3 files in SDL. Using SDL_Mixer, I am able to play one MP3 file.

Mix_Music *music = Mix_LoadMUS("music.mp3");

Mix_PlayMusic(music, 0);

But when I am trying to play another MP3 along with first one, the first one stops and it plays the 2nd one. Can any one help on this?

Not sure about mp3, but it seems like wave files can be played simultaneously using [channels](http://www.libsdl.org/projects/SDL_mixer/docs/SDL_mixer_25.html#SEC25). Perhaps you can convert your MP3 to WAV and then use them instead? — Hjorthenify, Feb 24 '14 at 11:12
As per my requirement, i need to play mp3s only. mp3 will be loaded dynamically. — Prithveesh, Feb 25 '14 at 06:25

score 1 · Accepted Answer · answered Dec 23 '15 at 04:57

SDL_mixer is meant to be a super-simple audio library; a single music track is one of its limitations.

You could play the music as multiple sound effects. There are a few downsides though:

You'll have to manage pausing/volume/looping yourself, by keeping track of the channels used to play the sounds. Not too difficult, but it's code you have to write.
The sounds won't be streamed, so all your music tracks will be decoded and loaded into RAM uncompressed. These days uncompressed audio isn't that bad - to calculate uncompressed size, simply multiply num_channels * sample_rate * bit_rate * duration_in_seconds, which works out to be 2 * 44100 * 2 * 60 or 10584000 or ~10mb per minute of stereo, 44.1kHz 16-bit (i.e. 2-byte) audio. It's something to watch out for in embedded or low-end systems.

Alternately, you can use a more advanced audio library that supports multiple music channels.

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