Hello all,

Bass is a very good library for sound playing and recording. However, it's not included as an standard feature of Freepascal. For whom wich wants to work with standard components, are there other options: (1) to play sounds and (2) to record sounds?

Regards,
Luciano

You can use OpenAL or SDL...

2012/6/9 luciano de souza :

Our company uses SDL with good results in our cross-platform projects.

I took a look in Openal examples. I need to confess that I expected something easier. Perhaps, something like:

PlaySound('file.wav', 0)

In MMSystem, we have something like that, but it's not cross platform.

The examples present hundreds of lines. It's something frightful!

Regarding the complexity, probably is's possible to do much more than simply play a sound. In spite of that, it would be intersting to have something easier.

The examples work with complex and for me, abstract structures. Which kind of content, do I need to study to understand Openal or SDL?

2012/6/9, luciano de souza :

On the lazarus forum, kpjcomp made a wrapper for Openal. Haven't tested it but his example code is as simple as:

  openAl := TLazOpenAL.Create;
  wav1 := TLazOpenALWavFileSource.Create('drumloop.wav');
  wav1.looping := true;
  openal.SourceList.Add(wav1);
  wav2 := TLazOpenALWavFileSource.Create('chimes.wav');
  openal.SourceList.Add(wav2);
  wav1.play;
  wav2.play;

Perhaps worth looking at.

Ludo

On the lazarus forum, kpjcomp made a wrapper for Openal.

Forgot the link:
http://www.lazarus.freepascal.org/index.php/topic,17164.msg94588.html#msg945 88

Ludo

You need to wrap OpenAL a little to get something so simple.

In my Castle Game Engine (http://castle-engine.sourceforge.net/), I have SoundEngine wrapper, with which you can play sound like

   Buffer := SoundEngine.LoadBuffer(FileName);
   SoundEngine.PlaySound(Buffer, false, ...);

See working example in SVN on
http://svn.code.sf.net/p/castle-engine/code/trunk/castle_game_engine/examples/audio/alplay.lpr

You may want to look at the source (LGPL) to see how it's done :)

Michalis

Hello,

Please see this demo too:

https://github.com/silvioprog/lazsolutions/tree/master/Demos/LSPlayWAV

It is a cross function to play wav files.

2012/6/11 Ludo Brands :
[...]

Hello Ludo. :)

Where do I find the openal_nt unit?

unit1.pas(9,3) Fatal: Can not find unit openal_nt used by Unit1.

2012/6/11 Michalis Kamburelis :

Nice project. :)

castle_game_engine-3.0.0-src.zip = +-70MB.

Hm... you could send only the files to play audio? :/

silvioprog wrote

Nice project. :) castle_game_engine-3.0.0-src.zip = +-70MB.

Most of the size comes from the examples, they contain also example 3D data files (models, animations etc.). I prefer to give people full package :) For those who want to get parts, they can always check out appropriate directories from SVN.

Hm... you could send only the files to play audio? :/

The directories src/base/ and src/audio/ from the engine source code should be all you need. And examples inside examples/audio/, and examples/3d_sound_game/ (only in SVN), are probably useful :) Note that if you only get a subset of src/ directories, you will need to prepare also special Lazarus package to compile them (as the default package inside packages/castle_base.lpk includes other units, to deal with 3D, images, scripting and such), or compile only with ./xxx_compile.sh scripts (Unix or Cygwin required). It will be easier to just get the full zip/tar.gz archive, and simply ignore (don't look inside :) directories that don't interest you :)

Michalis

2012/6/11 Michalis Kamburelis :

Does not seem very easy to use hehehe.., but I will try test it later. :)

Thx Michalis! ^^

Where do I find the openal_nt unit? unit1.pas(9,3) Fatal: Can not find unit openal_nt used by Unit1.

At the bottom of the forum page is a link to a complete demo project openaltest.zip that includes the units laz_openal and OpenAL_NT.

Ludo

Jorge Aldo G. de F. Junior wrote

You can use OpenAL or SDL...

Found a framework that apparently uses SDL. Says it plays OGG and WAV.

Haven't tried it..

https://github.com/freezedev/elysion

Regards,
Reinier

SDL is so easy, it's hardly necessary to create a wrapper.

Michael.

SDL is so easy, it's hardly necessary to create a wrapper.

+1

And because SDL is a cross platform framework, there is nothing special to do in your code to get it to work on multiple platforms.

2012/6/12 Graeme Geldenhuys :

So, how to play audio (wav/mp3) with only SDL framework in Free Pascal?

silvioprog wrote

So, how to play audio (wav/mp3) with only SDL framework in Free Pascal?

Simply reading a SDL tutorial or two, will quickly let you understand the following code. TSoundEngine is just an convenience class we created to add extra sound events and possibly swap out sound library frameworks in future - without needing to change our application code. Simple design pattern practices to simply your application code and hide complexity.

This is not the complete code, but is the gist of it.

uses
sdl_mixer,

  sdl;

const
  // Global default extension for sound files. Set up as needed.
  SoundExt           = '.wav';
type
  PSoundBlock = {$IFDEF UseMusic}PMIX_Music{$ELSE}PMIX_Chunk{$ENDIF};
  ...
 { in our project, this code is in a TSoundPlayer class. Result is of
type PSoundBlock }
    Result := {$IFDEF
UseMusic}Mix_LoadMUS{$ELSE}Mix_LoadWAV{$ENDIF}(PChar(aFilename));
    if not Assigned(Result) then
      SoundEngine.MixError;
  ...
constructor TSoundEngine.Create;
begin
  if SDL_Init(SDL_INIT_AUDIO or SDL_INIT_TIMER) = -1 then
    SDLError;
  if Mix_OpenAudio(MIX_DEFAULT_FREQUENCY, MIX_DEFAULT_FORMAT,
MIX_DEFAULT_CHANNELS, 1024) = -1 then
    MixError;
  {$IFDEF UseMusic}Mix_HookMusicFinished{$ELSE}Mix_ChannelFinished{$ENDIF}(@MusicFinished);
end;
destructor TSoundEngine.Destroy;
begin
  PlayingStop;
  MIX_CloseAudio;
  SDL_Quit;
  inherited Destroy;
end;
procedure TSoundEngine.PlayingStop;
begin
  {$IFDEF UseMusic}
  Mix_HaltMusic;
  {$ELSE}
  Mix_HaltChannel(1);
  {$ENDIF}
end;
procedure TSoundEngine.PlayingStart(aMusic: PSoundBlock);
begin
  {$IFDEF UseMusic}
  if Mix_PlayMusic(aMusic, 0)  0 then
    MixError;
  {$ELSE}
  Mix_PlayChannel(1,aMusic, 0)
  {$ENDIF}
end;
procedure TSoundEngine.PlayingPause;
begin
  {$IFDEF UseMusic}
  Mix_PauseMusic;
  {$ELSE}
  Mix_Pause (1);
  {$ENDIF}
end;
procedure TSoundEngine.PlayingContinue;
begin
  {$IFDEF UseMusic}
  Mix_ResumeMusic;
  {$ELSE}
  Mix_Resume (1);
  {$ENDIF}
end;

2012/6/12 Graeme Geldenhuys :

Hellow Graeme! :)

I'll try to test it tomorrow and return here with the results ...

Thank you in advance guy! :)

2012/6/12 Graeme Geldenhuys :

[...]

I tried playing a wav file with this demo in attached, no errors, but no sound came out. :(

I downloaded all DLLs here:

http://www.libsdl.org/

http://www.libsdl.org/projects/SDL_mixer/

silvioprog wrote

I tried playing a wav file with this demo in attached, no errors, but no sound came out. :(

You are releasing the TSoundEngine instance to quickly, and don't give SDL chance to initialize fully and play the sound. Simply add a sleep(1000) call [just for demonstration purposes] after you called PlayingStart(), then you will hear the sound.

A better idea would be to change your code as the attached unit. Keep the TSoundEngine instance in the form (or as a global variable), so then playing any sounds are instant.

I don't know what to say, other than.... It works here - with or without the UseMusic define. And as I mentioned, we have a project that uses SDL a lot, on Linux and Windows, and tested on many versions of each of those OS'es.

I'm not on my normal development PC now - I'm using a 8 year old P4 Dell laptop with the following setup....

Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

c:\dev\fpc\2.5.1\bin\i386-win32>fpc -i
Free Pascal Compiler version 2.5.1

Compiler Date : 2011/11/26
Compiler CPU Target: i386

I'm also using Lazarus 0.9.30, but the version of Lazarus shouldn't make any difference with the SDL support.

YYYYYYYYYEEEEEEEEEEEESSSSSSSS!!!!!!!!!!

Worked fine with this demo in attached!

I found this demo in:

http://www.pascalgamedevelopment.com/showthread.php?4124-JEDI-SDL-Audio

Thx guys!

ps. I uploaded to:
http://code.google.com/p/lazarus-br/source/browse/#svn%2Ftrunk%2Fmultimedia%2FPlayWAV

Hi,

silvioprog wrote

YYYYYYYYYEEEEEEEEEEEESSSSSSSS!!!!!!!!!! Worked fine with this demo in attached!

Glad you got it working in the end.

I found this demo in:

...and if you look carefully, my sample code called the exact same SDL API's in the same order as the demo link your referenced.

Anyway, glad you got the sound playing going. :)

2012/6/14 Graeme Geldenhuys :

Hello Graeme,

I changed your code to(*) and it worked fine now. :o

http://pastebin.com/wMRad25q (or in attached)

Thx again!