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mp3fmod

Streaming MP3 from Internet with FMOD

I thought this would be a relatively simple task with something like FMOD, but I can't get it to work. Even the example code netstream doesn't seem to do the trick. No matter what mp3 I try to play with the netstream example program, I get this error:

FMOD error! (20) Couldn't perform seek operation.  This is a limitation of the medium (ie netstreams) or the file format.

I don't really understand what this means. Isn't this exactly what the netstream example program was for? to stream some file from the internet?

I can't get passed the createSound method

result = system->createSound(argv[1], FMOD_HARDWARE | FMOD_2D | FMOD_CREATESTREAM | FMOD_NONBLOCKING,  0, &sound);

EDIT:

This is what I modified after reading Mathew's answer

FMOD_CREATESOUNDEXINFO soundExInfo;
memset(&soundExInfo, 0, sizeof(FMOD_CREATESOUNDEXINFO));
soundExInfo.cbsize = sizeof(FMOD_CREATESOUNDEXINFO);
soundExInfo.suggestedsoundtype = FMOD_SOUND_TYPE_MPEG;

result = system->createSound(argv[1], FMOD_HARDWARE | FMOD_2D | FMOD_CREATESTREAM | FMOD_NONBLOCKING | FMOD_IGNORETAGS,  &soundExInfo, &sound);

I get two different errors depending on which files I use.

Test 1 URL: http://kylegobel.com/test.mp3

Test 1 Error: (25) Unsupported file or audio format.

Test 2 URL: http://kylegobel.com/bullet.mp3

Test 2 Error: (20) Couldn't perform seek operation. This is a limitation of the medium (ie netstreams) or the file format.

Before I made the change, I could use netstream to play "C:\test.mp3" which is the same file named test.mp3 on the web, but that no longer works with the above changes. Maybe these files are just in the wrong formats or something? Sorry for my lack of knowledge in this area, I really don't know much about sound, but trying to figure it out.

Thanks, Kyle

Solution

  • It's possible the MP3 has a large amount of tags at the start, so FMOD reads them then tries to seek back to the start (which it can't do because it's a net stream). Can you try using FMOD_IGNORETAGS and perhaps FMOD_CREATESOUNDEXINFO with suggestedsoundtype set to FMOD_SOUND_TYPE_MPEG?

    If that does't work could you post the url to a known not working MP3 stream?

    EDIT: The file in question has around 60KB of tag data, FMOD is happy to read over that stuff but for the MPEG codec to work it needs to do some small seeks. Since you cannot seek a netstream all the seeks must be contained inside the low level file buffer. If you tweak the file buffer size, make it a bit larger you can overcome this restriction. See System::setFileSystem "blockalign" parameter.