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Readme for FPlay v1.43 by Frank van de Pol
==========================================
26 May 1992
Description
===========
FPlay is a utility that allows you to play huge sound samples directly
from disc. To cope with small pauses in disc transfer (seek times) all
data is buffered in RAM. Using a optimised buffering scheme, it is
possible to play 20.833 kHz samples even from floppy disc.
The maximum size is currently restricted to 4 giga byte (if the filing
system permits). This yields in a sampling time of over 57 hours using
20.833 kHz sampling frequency (the standard on the archimedes).
To provide a decent quality when using low sample rates, it is possible
to use oversampling with linear interpolation. This makes the sound
quality of 8 kHz speech (or even music) samples quite acceptable
(contrary to !Armadeus). This option is very useful if you have an
external amplifier connected to the unfiltered sound output of the
archimedes (thus bypassing the low-pass filter), to reduce the
harshness of the sound (caused by intermodulation).
Disclaimer
==========
The author will not be liable for any damage, loss of profits,
goodwill or for any indirect or consequential loss arising out of
your use of this application, or your inability to use it, even if
the author has been advised of the possibility of such loss.
All efforts have been made to ensure the accuracy of the application.
However, should any errors be detected, the author would greatly
appreciate being informed of them. The above notwithstanding, the
authors can assume no responsibility for any errors.
Copyright notice
================
The FPlay utility is copyright © 1992,1993 of Frank van de Pol.
You may freely copy and use this program under the following
conditions:
1. You can GIVE this package to anyone you like, if and only if it
is distributed with all original files and with no changes made
to it.
2. If you want to put it on a BBS, include it in a PD library, or
store it at a FTP site you can do so, taking these notices into
account. You may not charge any money for it, apart from postage
and storage medium costs.
3. The entire package remains copyright of Frank van de Pol under
all circumstances. The copyright is NOT transferable.
Installation
============
For practical use, you should place the utility in a directory that
is in the Run$Path. Normally this will be the $.library directory on
the current filing system.
If you find it convenient to let FPlay playback your samples when they
will be double-clicked, you should set the following system variables:
Set alias$@RunType_D3C FPlay -armadeus -file %0
Set alias$@RunType_DF9 FPlay -start &1F0 -file %0
Usage
=====
FPlay can be controlled from the command line (*commands). Simply
typing FPlay results in FPlay displaying it syntax:
FilePlayer v 1.43 - (C) 26 May 1992 by F.K.W. van de Pol
Syntax: FPlay <Keywords>
Keywords are:
-file [filename]
-rate / -us [samplerate in µs] default=48
-unsigned
-buffers [number of buffers] default=4
-buffersize [buffersize in bytes] default=4096
-start [offset in file in bytes]
-oversampling [1, 2, 4 or 8 times] default=1
-armadeus [play armadeus format]
-ulaw [play ulaw format]
Keyword 'file' : This keyword specifies which file should be
played. If the filename is the first para-
meter, it can be omitted.
Keyword 'rate' : Use '-rate' to set the sampling rate ie. the
time between two samples expressed in micro
seconds. This equals to 1E6/sampling_freq.
Keyword 'us' : This has the same effect as the 'rate'
keyword.
Keyword 'unsigned' : Specify this flag if the samples are stored
in the unsigned format. As archimedes
samples are normally stored in signed format,
this flag is rarely used.
Keyword 'buffers' : This specifies the number of buffers in use.
Keyword 'buffersize' : This specifies the number of bytes per
buffer. The optimum value of the number of
buffers and the buffersize depend on the
seek time and data transfer rate of the
drive used. If the playback is not smooth
(small bits of silence while playing), you
should experiment with these values.
Keyword 'start' : Use this keyword to instruct FPlay to skip
the specified number of bytes. Use this to
skip the header used in some formats.
Keyword 'oversampling' : This keyword makes FPlay increase the
sampling frequency by a factor 1,2,4 or 8.
Intermediate samples are calculated using
linear interpolation. Care should be taken
not to overload the CPU, as oversampling
involves quite a lot of processing power.
Using a value too high will result in a
rather bad sound quality.
Keyword 'armadeus' : The 'armadeus' flag let FPlay derive the
sampling frequency from the samplefile
(the first byte in an !Armadeus file
represents the sampling rate.
Keyword 'ulaw' : Accept ulaw compressed logarithmic samples
instead of the usual 8 bit linear format.
Examples
========
You can play a sample (with name samplefile) using default settings:
*FPlay samplefile
or
*FPlay -file samplefile
Playing an !Armadeus file:
*FPlay samplefile -armadeus
Playing an !Armadeus file with a low sampling frequency:
*FPlay samplefile -armadeus -oversampling 4
Playing a EMR soundsynth file:
*FPlay samplefile -start &1F0 -oversampling 2
etc.
Known bugs
==========
None
How to contact the author
=========================
You can contact me at the following address:
Frank van de Pol
mgr. Nelislaan 10
4741 AB Hoeven
The Netherlands
Postgiro account: 5826066
Internet Email may be addressed to:
frankp@stack.urc.tue.nl
or
erikp@stack.urc.tue.nl
Last message
============
Any reactions, comments, bug reports (???), money, letters of thanks,
programs, hardware, etc. can be sent to the addresses specified above.
Please remember: - If you don't like it at all, don't use it.
- If you have some complaints or wishes, find out what
you would like to have added or changed in order to
make this program useful to you, and maybe I can do
something about it.
- If you like it a lot, I would very much like to hear
that from you too. Humans do like compliments (like
dogs do), so if you want to, you can send a nice
colourful post card to the address below.
- If you don't like my english, send me an english
dictionary!