BlitzMax wav format

BlitzMax Forums/BlitzMax Programming/BlitzMax wav format

Raz(Posted 2012) [#1]
Hi,

I appear to be having some problems with certain wav files. I believe it to be an encoding issue but I am not sure what I should be doing during said encoding process!

Any tips?

Ta! :)


Midimaster(Posted 2012) [#2]
you cannot open every *.WAV named file, because their are a lot of other formats allowed to use the extension WAV. Windows Media Player also detects MPEG-Layer3 or GSM, when they are renamed as WAV.

So a WAV-File can contain a lot of Codex.

BlitzMax only plays "real" oldstyle WAVs formerly known as PCM-Format.


Raz(Posted 2012) [#3]
Sorry was meant to say thanks a while ago!

For some reason it didn't work for all wav files, but I used this : http://www.freac.org/ to resave and fix most of them.


ziggy(Posted 2012) [#4]
As far as I know, there are only 2 kind of WAV files (excluding non wav files that are renamed as such)

ADPCM wich is compressed and unsupported by BlitzMax Audio engine.

PCM which is uncompressed and supported by BlitzMax

Then, the PCM encoding can have 8, 16 or 24 bits audio, and can have several interleaved channels (from one on a mono file, to 65536).

Not all audio hardware can play 24 bits audio, so a 24 bits wav could be not compatible with some BlitzMax audio drivers. Then, I'm not sure BlitzMax support audio with more than 2 channels in a single audio stream, so quadraphonic wav files can be unsupported too. As instance, on OpenAL only wav files with a single channel can be positioned on a 3D space (each driver can have its own limitations due technology and hardware).

So a WAV-File can contain a lot of Codex.
That's not correct, as a WAV file is not a container file format, so it does not have codecs. It has some subformats that are defined as number of channels, bit depth and ADPCM compression, all of them defined on the WAV header. It can also contain loop marks, etc. But not encoded audio data other than the uncompressed samples, or complessed ADPCM samples info.

EDIT: I've jsut checked that they CAN contain embeded codec-based compression of data. So my previous statement was wrong, but this is a recent addition.It seems those formats are currently supported: Microsoft GSM 06.10, CELP, SBC, Truespeech and MPEG Layer-3 So supporting all of them "out of the box" can be complicated. Specialy when some of them require additional licensing of propietary codecs.

Last edited 2012