Re: Hi-res picture packer?

[winstonsmith <winston19842005@yahoo.com>]

On Jul 1, 8:51 pm, Andy McFadden <fad...@fadden.com> wrote:
> John B. Matthews <nos...@nospam.invalid> wrote:
>
> > $ unzip -l compression.zip
> > Archive:  compression.zip
> >   Length     Date   Time    Name
> >  --------    ----   ----    ----
> >    143360  07-19-09 11:07   compressors/BeagleGraphics.dsk
> >    143360  01-24-08 17:47   compressors/HiresPicPac.dsk
>
> You need to use "-v" to see the interesting part:
>
>  Length   Method    Size  Ratio   Date   Time   CRC-32    Name
> --------  ------  ------- -----   ----   ----   ------    ----
>   143360  Implode   60517  58%  07-19-09 11:07  57c98c50  compressors/BeagleGraphics.dsk
>   143360  Implode   65726  54%  01-24-08 17:47  d0bace05  compressors/HiresPicPac.dsk
>  ...
>
> Note the method is "Implode", which went out of vogue many years ago
> after Unisys got twitchy about LZW.
>
> It'd be more portable -- and 50KB smaller -- if the common Deflate
> algorithm were used.
>

Yes, but then I wouldn't be able to use my Dezip program I wrote for
the TI-99 back in 1989 on it!
I gave up when v2.04 came out - the memory usage was just too much for
32k! I already had to use an overlay and store half of one of the
stacks in VDP RAM... I almost tackled it again about 10 years ago, but
thought better of it...