Re: [midatlanticretro] Partially OT: WAV file processing question
- I took Pascal in college but it has been about 15 years since I have used it. I might be able to help with the Pascal. I do have books on Pascal if you want to borrow them. Let me know.----- Original Message -----From: Jim ScheefSent: Tuesday, November 25, 2008 2:49 PMSubject: Re: [midatlanticretro] Partially OT: WAV file processing question
Rich and Bill,
This is an interesting project. From a programming standpoint on a PC
maybe it would be good to write a program that can read and process a
standard WAV file but swallow the header and trailer info in the WAV and
just pass on the data part to the "Altair". The reverse might be useful
as well - to accept the data sounds and output a standard WAV.
Rich, Pascal is obtuse because the code is "upside down". Pascal
requires that a subroutine be defined before it can be referenced.
Pretend the code is VB but read each section starting at the bottom of
the listing (where program flow actually begins) and it will make more
Bill Degnan wrote:
> > Richard A. Cini wrote:
> > > All:
> > >
> > > I've been asked to add direct support for WAV file images of real
> > > Altair cassette tapes in the Altair32 Emulator. Essentially a WAV
> > > file, minus the header, is a series of numbers that represent the
> > > sample. Since the sample is 8-bit monaural, each sample is just one
> > > byte. The sampling frequency is 22.050kHz. The recording is 124
> > > seconds long, so there are about 2.7 million samples. The 88-ACR used
> > > a 2400Hz/1850Hz tone pair to represent logic 1 and 0, respectively. In
> > > the end, I need to turn these samples into live bits and bytes.
> > >
> > > I'm not exactly sure where to start with this programming project. Has
> > > anyone on-list ever done this kind of software audio processing?
> > > Basically the audio segment of the board has some signal conditioning
> > > and an XR210 FSK demodulator.
> > >
> > > Any help would be appreciated. Thanks.
> > >
> I plan to work on this project independently, from a sound engineer
> perspective. I will let you know how it goes. I could be wrong, but I
> believe it's more the levels/mix than the sample rate. There is nothing
> wrong with over-sampling the sound source. The master of any program on
> tape was usually a record album. I wonder if the original BASIC record
> albums exist.