PSN-L Email List Message

Subject: Re: PSN file format
From: "Larry Cochrane" cochrane@..............
Date: Mon, 9 Jul 2001 00:18:53 -0700


I just ran an experiment. I saved a PSN Type 4 file to a ASCII file. The
original file was 84k long or ~7 minutes of data at 100 SPS. The ASCII file
was 367k in length, that's over 4 times bigger then  the original. That's
the main reason to save data like this in binary format. In fact, I would
like to compress the data so the event files are even smaller. Saving a lot
of event files in ASCII format means 4 times more disk space, more backup
storage if you backup your files, and 4 times longer to download them over
the internet. Since I archive the event files for the PSN, keeping each
event file as small as possible is important too me. This is why my system
will not except them if you try to send one to my event archive email
address. Looking at last months directory (06/2001) I see 190 files using
over ~25 megabytes of disk space. That would be over 100 mb if they were all
in the ASCII format.

More comments below....

> Larry,
> excuse me for loving ASCII format.
> But i think you should consider the utility of the ascii format and don't
> abandon it.
> A good binary header even if will be good in the very sense of the word
> without doubt PSN4 is)
> is always limited to his structure.

Sorry, not true. The new format (
has a fixed section and a variable header section. With the variable header,
one can add new data field without interfering with old versions of WinQuake
or other programs that can read in the data. Recently I added new fields to
the PSN Type 4 format. Older versions of WinQuake would skip this data,
newer versions can display and modify the new information with out any
problems. BTW, the new fields are not saved or read in using the ASCII
version. I do not want to support two formats....

>The power of popular software like
> Excel, Access an so on (mathlab)
> is that they can treat any kind of ascii files using a programmable record
> separator and a field separator.

And that's why I added the ability to import/export event files in an ASCII
format.  That doesn't mean they need to be stored in the format.

> Windows too uses the INI files that are always ASCII. In the majority of
> cases using
> ascii file you can add and remove a field without losing the compatibility
> with higher and lower versions.

There's a big difference between an event file with lots of samples and an
INI file. For what's it worth all of my INI files are ASCII. As far as
losing compatibility see above.

-Larry Cochrane
Redwood City, PSN


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Larry Cochrane <cochrane@..............>