What is FMOD

What is FMOD?

FMOD is an easy to use crossplatform audio engine, available on the

Windows, Windows CE, Linux, Macintosh, GameCube, Playstation 2 and

XBox platforms. It can be used with C/C++, Visual Basic, Delphi and

MASM. So, if you use one of those languages on one of these platforms

and you want to use sound in your application, FMOD is made for you. The

examples below will be in C although the basic principles should be the

same across all platforms.

Alternatives

One alternative might be OpenAL. OpenAL is another crossplatform audio

API which is available for Windows, Linux and Macintosh and can be used

with C/C++, Delphi and Java. The style is similar to OpenGL (for example,

the extensions technique is also used here).

A Windows-specific alternative would be DirectSound which is part of

Microsoft's DirectX.

What does it cost?

The developers of FMOD have a nice philosophy; if you don't intend to

make any money with your project, you can use it for free. So as long as

you don't make any profit with your program you don't have to pay anything.

However if turns out that you will sell your product you would then have to

buy a license, starting at $100 for shareware products. For more details

have a look the official licence price list at fmod.org.

From where can I get it?

To use FMOD in your application you need the headers and the library

which can be downloaded from http://www.fmod.org. At this time the recent

version is 3.70. Be aware that this version is not backwards compatible any

more!

Getting Started

http://www.openal.org/

http://www.fmod.org/

After unpacking the archive, you should copy the FMOD.DLL into your

working directory or better still, into the directory where your executable file

will be.

Before we can really start we have to do one last thing.

For C users

Now you only have to include the header "fmod.h" and depending on your

compiler, the right import library:

fmodvc.lib for Microsoft Visual C++ and Codewarrior

fmodbc.lib for Borland

fmodwc.lib for Watcom

fmodcc.lib for LCC-Win32

libfmod.a for MingW and CygWin

fmod-3-7.lib for GCC

For Delphi users

Include the unit FMOD in your uses clause.

For Visual Basic users

Add fmod.bas to your project.

Initialization

Before we can use FMOD to play some sounds for us we need to initialize

it. This is pretty simple:

FSOUND_Init (44100, 32, 0);

The first parameter is our output rate in hertz. In our example it's equal to

44100. The second parameter is our maximum number of software

channels. It doesn't matter if you choose a higher number due to the fact

that it won't affect your cpu usage as long as you don't really use them.

However 32 should be more than enough for this short introduction.

In the third parameter can we specify some flags if we want to. We leave

this parameter as 0.

That's it. Now we are ready to play some sounds. But in which format do

we have out sounds? Is it a song, a sample or a stream?

Songs, Samples and Streams

Now it's time to mention that FMOD is subdivided in two APIs; FSOUND

and FMUSIC. Which one you should use depends on the files you want to

play.

Sequenced music files like .MOD, .S3M, .XM, .IT, .MID, .RMI, .SGT

or .FSB are called songs and are supported by the FMUSIC api.

On the other hand, the FSOUND api is for PCM based or compressed files

like .WAV, .MP2, .MP3, .OGG or .RAW. They can be treated as either

samples or streams. If you want to play a short sound / a small file like a

gunshot then you treat the file as an sample. Samples will be

decompressed into memory before being played and can be played

multiple times. When you want to play a bigger file like continuous

background music then you handle the file as a stream. This will result in

more cpu usage because the file will be streamed from the disk in realtime,

but also needs less memory as a result. Another thing to note is that

streams cannot be played multiple times at once.

FMUSIC

Let's rock! To play a song you need a FMUSIC_MODULE variable for the

handle and following two lines:

handle=FMUSIC_LoadSong("YourFileName");

FMUSIC_PlaySong(handle);

You will notice that from now on almost every function needs the handle as

the first parameter.

Let's get loud

Now, that your song is playing you can manipulate it in several ways. To

make it louder you use:

FMUSIC_SetMasterVolume (handle, 256);

With 256 we set the volume to the maximum. If we would have passed 0

we would have have silence. To pause our song we use:

FMUSIC_SetPaused (handle, true);

and

FMUSIC_SetPaused (handle, false);

when we want to unpause it.

For background music it would be nice if our music would play in an

endless loop. No problem:

FMUSIC_SetLooping (handle, true);

And when we are tired of hearing the music we will stop it with:

FMUSIC_StopSong (handle);

Cleaning Up

To free the allocated memory from a song you should simply call:

FMUSIC_FreeSong (handle);

and we're done. Pretty easy, isn't it?

A small simple console example

In this example (for Windows compilers) we'll play a file called 'canyon.mid'

and wait until the user hits a key to exit the program. Remember to link the

correct library and use the right paths for the header and the midi file.

#include

#include "inc/fmod.h"

FMUSIC_MODULE* handle;

int main ()

{

// init FMOD sound system

FSOUND_Init (44100, 32, 0);

// load song

handle=FMUSIC_LoadSong ("canyon.mid");

// play song only once

// when you want to play a midi file you have to

disable looping

// BEFORE playing the song else this command has no

effect!

FMUSIC_SetLooping (handle, false);

// play song

FMUSIC_PlaySong (handle);

// wait until the users hits a key to end the app

while (!_kbhit())

{

}

//clean up

FMUSIC_FreeSong (handle);

FSOUND_Close();

}

FSOUND

Due to the fact that you have more possibilities while using FSOUND it's a

little bit more complicated. For instance, you have several channels which

you can use simultaneously. But in this short introduction we will only be

using one. First we have a look at samples, and afterwards we move on to

streams.

Samples

Let's rock!

To play a sample you need a FSOUND_SAMPLE variable for the handle

and following two lines:

handle=FSOUND_Sample_Load (0,"YourFileName",0,0,0);

FSOUND_PlaySound (0,handle);

The first command loads the sample. For the beginning only the second

parameter is relevant - the name of the file you want to play! The rest is

important when you want to use more than one sample, play a file from

memory, etc. The second command plays the actual sample. The first

parameter is the channel number you want to use and the second one the

handle of the sound to play. Take care that the file that you want to play is

not that big! Otherwise, it will take a while until the file will be played

because it is first loaded completely into memory.

Let's get loud

Now, that your sample is playing you can manipulate it in several ways.

To make it louder you use:

FSOUND_SetVolume (handle, 255);

With 255 we set the volume to the maximum. As with the music, if we had

had passed 0 we would have had silence. You can adjust the volume for a

sample by passing a handle, or you can also adjust a channel by passing

the relevant channel number instead of a handle.

To pause our sample we use:

FSOUND_SetPaused (handle, true);

and

FSOUND_SetPaused (handle, false);

if we want to unpause it. Again the first parameter can be a channel

number.

When we want to stop the sample we just use:

FSOUND_StopSound (handle);

And once again can the parameter be a channel number.

Cleaning up

To unload the sample a simple

FSOUND_Sample_Free (handle);

is enough.


Nothing fancy here. This snippet just plays the file sample.mp3.

#include


FSOUND_SAMPLE* handle;

int main ()

{

// init FMOD sound system

FSOUND_Init (44100, 32, 0);

// load and play sample

handle=FSOUND_Sample_Load (0,"sample.mp3",0, 0, 0);

FSOUND_PlaySound (0,handle);

// wait until the users hits a key to end the app

while (!_kbhit())

{

}

// clean up

FSOUND_Sample_Free (handle);

FSOUND_Close();

}

Streams

Let's rock!

To play a stream you need a FSOUND_STREAM variable for the handle

and the following two lines:

handle=FSOUND_Stream_Open("YourFileName",0, 0, 0);

FSOUND_Stream_Play (0,handle);

It's pretty much the same as samples so nothing more to say here.

Note: Take care that you're using at least version 3.7. In earlier versions

the command for opening a stream was different!

Let's get loud

Here you can use the same functions as listed with the samples. I just want

to mention one additional function here:

To stop a stream you use:

FSOUND_Stream_Stop (handle);

Cleaning up

To unload the stream a simple

FSOUND_Stream_Close(handle);

is enough.


This small example streams the file sample.mp3.

#include


FSOUND_STREAM* handle;

void main ()

{

//init FMOD sound system

FSOUND_Init (44100, 32, 0);

//load and play sample

handle=FSOUND_Stream_Open("sample.mp3",0, 0, 0);

FSOUND_Stream_Play (0,handle);

//wait until the users hits a key to end the app

while (!_kbhit())

{

}

//clean up

FSOUND_Stream_Close(handle);

FSOUND_Close();

}

Shutting Down

To shut down the FMOD sound system just call at the end of your program:

FSOUND_Close ();

What's coming next?

Of course are there more things you can do with FMOD. 3D sound,

handling CDs and effects are just a few to mention. All in all it's not that

complicated but it is definitely pretty powerful. So, it should be easy to read

through the help file and find what you need.

Final Words

I wrote this short article after I saw the article about OpenAL by Lee

Winder at Gamedev.net. A short time later the question about how to play

sound in an application came up in the forum. Even though the FMOD API

comes complete with some examples and brief tutorials these might not

seem as simple at the first glance. I hope this article was useful for you. For

any comments, questions, feedback, etc. send me an email

[email protected].

http://www.gamedev.net/reference/articles/article2008.asp

http://www.gamedev.net/reference/articles/article2008.asp

http://www.gamedev.net/

mailto:[email protected]

A beginner's guide to FMOD

by Lachie D. (November 2007)

Introduction

This tutorial should introduce you with basics of using FMOD in

FreeBASIC programs. It's pretty much the summary of FMOD subs and

methods I use in my projects and does not represent the entire scope

of FMOD in FreeBASIC. If your needs extend beyond this tutorial, you

are encouraged to explore additional FMOD calls and its documentation.

Originally I planed to write a cross FMOD/FBSound tutorial, but as

FBSound felt rather user-unfriendly to me I gave up on that. If

someone likes and prefers FBSound, be so kind to write a tutorial

about it in the style of this one if you wish to popularize the

library in question.

What is FMOD?

FMOD is a 32-bit sound library for Windows, Linux and Macintosh. It is

free of charge for freeware products, but if you plan to use it in

commercial products you'll have to buy a specific license. Visit

www.fmod.org for more info on this.

What do you need?

Well, you need FreeBASIC first. I assume you have one. As the code in

this tutorial was written in FreeBASIC ver.0.18 or later, get that.

You also need FMOD.DLL placed in Windows/System32 directory or where

you place the program source code. Get it here:

http://www.fmod.org/index.php/download#FMOD3ProgrammersAPI

To test the example program in this tutorial download the following

sound files: fmodtutfiles.zip

Initiating FMOD

To use FMOD in your programs you need to include "fmod.bi" with:

#include "fmod.bi"

After this we'll declare several variables that will become necessary

later.

CONST number_of_sound_effect = 10

CONST FALSE = 0

CONST TRUE = 1

DIM SHARED PlaySound AS INTEGER

DIM SHARED sample(number_of_sound_effect) AS INTEGER PTR

DIM SHARED music_handle AS INTEGER PTR

DIM SHARED SFXVolume AS INTEGER, MusicVolume AS INTEGER

PlaySound will be used to flag if FMOD functions should be used or not

(if FMOD initiation failed), sample array will hold the sound effects

and declare it like I did. number_of_sound_effect represent the number

of sound effects you'll use in your program. Change this number to

suit your own needs. music_handle will flag the current music track in

memory which we'll stream. I advise streaming music files instead

loading all of them into memory.

SFXVolume will flag the current sound effects volume, while

MusicVolume the music volume.

The following code initiates FMOD:

PlaySound = TRUE

FSOUND_Init(44100, number_of_sound_effect+1, 0)

IF FSOUND_Init(44100, number_of_sound_effect+1, 0) = 0 THEN PlaySound

= FALSE

PlaySound is set as TRUE by default, and then it's set to FALSE if

FMOD fails to initiate. The first parameter in FMOD_Init is mixrate in

Hz, usually set to 44100 as most sound files have that mixrate. The

second parameter is the number of SOFTWARE channels available. I added

one more channel on the number of sound effects I’ll use because I

need one more for my music track. You can put any number here, just

make sure it's more than the number of sound effects and music tracks

you'll allocate at the same time in your program.

Loading samples

To load a sound effect use FSOUND_Sample_Load function on the

following way:

IF PlaySound = TRUE THEN

sample(1) = FSOUND_SAMPLE_Load(FSOUND_FREE,"sound1.wav",0,0,0)

sample(2) = FSOUND_SAMPLE_Load(FSOUND_FREE,"sound2.wav",0,0,0)

END IF

The first parameter flags the sample slot (index). FSOUND_FREE chooses

an arbitrary one. The second parameter is the name of the sound file.

You can load MP3, WAV, OGG, RAW, and other file formats with this

function. With the third parameter you can set the mode for that sound

effect (check FMOD documentation for the description of available

modes), fourth one flags the offset inside the file, and the last one

flags the length of a memory block for that sound effect. Unless

having special requirements, use zeros for those parameters as I did.

Let's set the default music and sound effects volumes:

SFXVolume = 3

MusicVolume = 3

I use 4 steps volume but you can use more. In my method 4 represents

maximum volume, 3 is 75 % of maximum volume, 2 is 50 %, 1 is 25 %, and

0 is mute.

To start streaming a music (or environmental) track I constructed the

following subroutine:

SUB playStreamMusic (musc As String)

DIM SetVol AS INTEGER


music_handle = FSOUND_Stream_Open(musc, FSOUND_LOOP_NORMAL, 0,

0 )

FSOUND_Stream_Play(1, music_handle)

IF MusicVolume = 0 THEN SetVol = 0





FSOUND_SetVolumeAbsolute(1, SetVol)

END IF

END SUB

Be sure to declare this subroutine.

To stop streaming a sound file (which is usually a music track) I use

the following subroutine:

playStreamMusic ("river.ogg")

FSOUND_Stream_Open opens a sound file for streaming. The first

parameter flags the sound file (string), the second parameter flags

the mode of streaming (how the file should be played; refer to FMOD

documentation for more info on this), and the last two parameters are

0 by default and flag the offset and length of a memory block for the

streamed sound file. FSOUND_Stream_Play starts streaming the file

flagged with music_handle. I used channel index 1 because we'll use

the same to control the volume of the streamed music track (a way to

divide the volume of sound effects and music). Note how I used

MusicVolume to set the volume of the streamed track (255 max, 0 mute).

FSOUND_SetVolumeAbsolute sets a channel volume linearly. This function

is NOT affected by master volume. It is used when you want to quiet

everything down using FSOUND_SetSFXMasterVolume, but make a channel

prominent.

To stop streaming a sound file I use a following subroutine:

SUB stopStreamMusic()


FSOUND_Stream_Stop music_handle

FSOUND_Stream_Close music_handle

END IF

END SUB

I recommend you to stop streaming a file before you change it to

another one. If you are more imaginative, you can come up with volume

fade in / fade out effects when tracks are changed, but I don't want

to complicate this tutorial with that.

For playing sound effects I use the following subroutine in

conjunction with a volume setting subroutine:

SUB playsample (plsnd as integer ptr)


FSOUND_PlaySound (FSOUND_FREE, plsnd)

setSoundVolume

END IF

END SUB

SUB setSoundVolume

DIM SetVol AS INTEGER


IF SFXVolume = 0 THEN SetVol = 0





FSOUND_SetSFXMasterVolume(SetVol)






FSOUND_SetVolumeAbsolute(1, SetVol)

END IF

END SUB

Note how the sound effects volume is set every time a sound effect if

played, and how in the same time the music volume (channel 1 volume)

needs to be RESET.

To play sound effect 1 use:

playsample (sample(1))

You don't have to use a sample array like it did. If you for example

create an integer pointer named splash and properly load a sound

effect with it, then you'll use:

playsample (splash)

To test all this code create a loop like this one:

SCREENRES 640, 480, 32, 1, GFX_WINDOWED

DO

IF PlaySound = TRUE THEN FSOUND_Update

LOCATE 1,1

PRINT "PUSH ESC TO END PROGRAM"

PRINT "PUSH 1 AND 2 TO TEST SOUND EFFECTS"

PRINT "PUSH F1 AND F2 TO CHANGE THE WATER SOUND VOLUME"

IF MULTIKEY(SC_1) THEN


SLEEP 1000

END IF

IF MULTIKEY(SC_2) THEN


SLEEP 1000

END IF

IF MULTIKEY(SC_F1) THEN

MusicVolume = MusicVolume - 1

IF MusicVolume < 0 THEN MusicVolume = 0

setSoundVolume

SLEEP 1000

END IF

IF MULTIKEY(SC_F2) THEN

MusicVolume = MusicVolume + 1

IF MusicVolume > 4 THEN MusicVolume = 4

setSoundVolume

SLEEP 1000

END IF

SLEEP 10

LOOP UNTIL MULTIKEY(SC_ESCAPE)

FSOUND_Close

Use 1 and 2 to test the two sound effects, F1 and F2 to change the

music volume. I've been told that using FSound_Update is not necessary,

but heck, it doesn't hurt. Note how FSound_Close is used before the

program ends. Always be sure to close FMOD when you end your program.

The entire code so far: codever1.txt

Few more statements I want to show you.

To pause currently streamed music track use

FSOUND_SetPaused (1, 1)

Note that the first parameter is the channel, so this will work only

if you are streaming the music track in that channel.

To start streaming it again use:

FSOUND_SetPaused (1, 0)

That's all!

This is just the surface of FMOD. I warmly recommend you to explore

"fmod.bi" and FMOD documentation.

Happy coding!

What is FMOD

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