WAV as input format and output format

[dennisguse]

Almost all programs use a headerless binary format aka raw as input format and output format.
This is an issue due to endianess, sample rate, and word width (ie, files must be in the correct format, but are not self-describing).

This can be easily overcome by using WAVE instead of raw.

Libsndfile is a LGPL2 library for reading and writing wave files.
API is straight forward.

NOTE: This task requires to also adjust all concerned software tests.

Non-working demo code taken from https://github.com/TheTelephone/TheTelephone/blob/master/src/support/readsfnow_tilde.c:

//Read file completely.
SNDFILE *infile = NULL;
SF_INFO sfinfo;
memset (&sfinfo, 0, sizeof (sfinfo));

if ((infile = sf_open (x->filename, SFM_READ, &sfinfo)) == NULL) {
  char pwd[512];
  getcwd (pwd, 512);

  error (" Not able to open input file %s/%s: %s.", x->filename, pwd, x->filename, sf_strerror (NULL));
  return NULL;
}

if (fabsf (sys_getsr () - sfinfo.samplerate) > 0.0001) {
  error ("Sampling rate of input file (%d Hz) does not match Puredatas (%f Hz).", x->filename, sfinfo.samplerate, sys_getsr ());
  return NULL;
}

x->channel_count = sfinfo.channels;
x->wave_data = (float *) malloc (MAX_BUFFER * sizeof (float));
x->wave_length = sf_read_float (infile, x->wave_data, MAX_BUFFER);
x->frame_count = sfinfo.frames;

sf_close (infile);