Re: Microsoft RIFF, WAVE audio data, 1 bit, mono 8000 Hz

[Alan Cox <alan@lxorguk.ukuu.org.uk>]

> I have a (free) voice mail service that provides the messages in a wav
> file which file(1) specifies as:

Dial it up and send it a steady tone square wave at about 1KHz. 
If my guess to the format is right then you will get back something vaguely
like 
	FF,00,FF,00,FF,00,FF,00

THen you can figure the bitendianness they use. Basically its exactly what
it sounds like - single bit above/below threshold values.

So you'd do 

	while(len)
	{
		uchar i=*data++;
		int ct;
		for(ct=0;ct<8;ct++)
		{
			if(i&0x80)
				play8bit(0xFF);
			else
				play8bit(0x00);
			i<<=1;
		}
		len--;
	}