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Re: Hi-res picture packer?
On Jun 11, 9:25 pm, gnudutch <gnudu...@gmail.com> wrote:
> Hi all,
>
> I'm looking for a program that I used in the past for compressing hi-
> res pictures. I think the name was "Hi-res picture packer" or
> something similar. I thought it was from Nibble magazine, but after
> purchasing the complete archives I am unable to find the program.
> (There is a "Super Hi-res picture packer" which may explain my
> confusion)
>
> I've seen other programs that can pack pictures, including Beagle Bros
> scrunch. But the one I want is different because it was menu driven
> and it turned the hi-res screens into binary files that you can BRUN.
> It also featured a pleasant reveal effect. It was terrific for
> spicing up Applesoft programs.
>
> Does anybody remember this beast? It ran fine under ProDOS and it was
> from the 1989-1990 time frame.
>
> Thanks for any help,
>
> --g
There were no packed pictures that could be BRUN that I know of, as
that would mean the decompression algorithm would need to be included
with the picture, and that extra overhead would kind of defeat the
space savings from a decompressed file to begin with. There are a
number of ways to make a graphic BRUNnable. The simplest would be to
put a small header at the beginning of each graphic like this:
$1FED: 2C 54 C0 2C 57 C0 2C 52 C0 2C 50 C0 20 C FD 2C 51 C0 60
The graphic starts at $2000-$3FFF for page 1 and $4000-$5FFF for page
2. If you would like the graphics to start on page 2 then a slight
change to the header:
$3FED: 2C 55 C0 2C 57 C0 2C 52 C0 2C 50 C0 20 C FD 2C 51 C0 60
Then to save the graphic
BSAVE graphic,A$1FED,L$2013
There is also a way to insert this code into the screen holes within
the graphic itself so the file is no longer than $2000 bytes, I have
that program as well that allows you to do this.
If you want higher compression, I wrote a graphics compression program
that compresses a little better than Scrunch and saves on average 2-3
extra blocks under Prodos or 4-6 sectors under Dos3.3
I have also expanded the compression algorithm to handle double hi-res
graphics and can save from 3-7 blocks under Prodos over Double Scrunch
Rob