## To build:

``` <!---sh-->
    make
```


## To use:

``` <!---sh-->
    ./prog < textfile > output.gif
```


## Try:

To see the input files and feed them to the program, redirecting to GIF files:

``` <!---sh-->
    ./try.sh
```


## Judges' remarks:

To get the best experience, use a GIF viewer that can handle animated GIFs.
With macOS you can use Safari using `open -a Safari smily.gif`.

Some things to consider are that this 2.5KiB gem encodes a 96 character 8x8
font (naively this could already take 6144 bytes) and a GIF encoder.  But
how does it know which characters are closed?

You should only give this program printable ASCII characters.

Unfortunately this won't run on your PDP8, if you had one, as it needs at
least 2MiB of memory to run in.


## Author's remarks:

This program generates an animated GIF from a plain text.  Run:

``` <!---sh-->
    cc -o prog prog.c
    ./prog < invisible.txt > invisible.gif
```

Open `invisible.gif` with a GIF viewer that can show animated GIFs and then wait
a minute.  You will see a hidden message.  Can you tell the difference between
letters that leave the mark and ones that do not?

Other examples:

``` <!---sh-->
    ./prog < golem.txt > golem.gif
    ./prog < smily.txt > smily.gif
```

The program itself has a hidden message.

``` <!---sh-->
    ./prog < prog.c > prog.gif
```

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