This is the calling script that the cron job kicks off. It should download the images, and rename them to epoch seconds. Fifth, yes I know I shouldn't use system as I do, but in this particular case, I figured the chances of actually having this hole exploited was low, especially since I know the names of all the images before hand.

#!/bin/bash
#you need to do a wget here.
image_path=some_path
image_dest=some_other_path
for i in `ls ${image_path}*.jpg`
do
    mv -f $i ${image_dest}/image-`stat -c "%Y" $i`.jpg
done
touch .rename.config.txt
./convert_day.pl ${image_dest}/*
[download]

So now we get to the perl (finally.) Things you should note, first you should have write access to . Second, this uses a persistent data structure. Third, becuase of it's persistent data structure, it would be bad to have more than 1 copy running at the same time in the same path. Fourth, yes I know there can be a lot of time improvements, but those are minimal compared with the time it takes to run convert on 10+ images.

#!/usr/bin/perl
use strict;
use Time::localtime;
use Data::Dumper;
my %pics;
my %exec_hash;
my @elements;
my $FH;
my $final_path="some_path";

# the user should ensure that this script is only run serially
open(FH, "< .rename.config.txt");
my $line;
my $lines = "";
while (defined ($line = <FH>)){
    $lines .= $line;
}
%exec_hash=%{eval $lines} unless $lines eq "";
close(FH);

# create the movie names and add images to the movies
for(@ARGV){
    my $temp = $_;
    my $tm = localtime((stat($temp))[8]);
    my $nm = sprintf("%02d%02d%04d", $tm->mon+1, $tm->mday, $tm->year+
+1900);
    push @elements, $nm unless defined $pics{$nm};
    $pics{$nm} = [] unless defined $pics{$nm};
    push @{$pics{$nm}}, $temp;
}

# convert the images to movies
for(@elements){
    my $t = $_;
    my $line = "convert -delay 10 " . join(" ", @{$pics{$t}}) . " ".$f
+inal_path."/" . $t . ".mpg 2>/dev/null 1>/dev/null" ;

    # As processing a lot of images takes a long time
    # only update those images which have changed
    if(!defined($exec_hash{$t}) || $exec_hash{$t} ne $line){
        system $line;
        $exec_hash{$t} = $line;
    }
}
my $save = pop @elements;
system "cat ".$final_path."/". (pop @elements) .".mpg ".$final_path."/
+". $save . ".mpg > ".$final_path."/current.mpg" ;

open($FH, ">.rename.config.txt");
$Data::Dumper::Terse = 1;
$Data::Dumper::Indent = 1;
print $FH Data::Dumper->Dump([\%exec_hash],['exec_hash']);
close($FH);
[download]

Feel free to comment away, suggest improvements, ect. One thing to note, mpgs can be catted together, thus reducing the time taken even more; however, I did discover a couple cases where the images were updated as wget was running, thus it missed an image, (which it filled in later using the kickoff script.) Also note, rsync commands can be added to the kickoff script to upload the movies automatically.

The results of all this are here.