use strict;
use warnings;
use Tk;
use POSIX;
my $red;
my $green;
my $blue;
my $mw = MainWindow->new;
$mw->title('Raw Renamer');
my $right_frame = $mw->Label->pack(-side => 'left', -anchor => 'n', -e
+xpand => 1);
my $text_frame = $right_frame->Label->pack(-side => 'left', -anchor =>
+ 'n', -expand => 1);
$text_frame->Label(-text =>"Red")->pack(-side => 'top', -anchor => 'w'
+);
$text_frame->Label(-text =>"Green")->pack(-side => 'top', -anchor => '
+w');
$text_frame->Label(-text =>"Blue")->pack(-side => 'top', -anchor => 'w
+');
my $variable_frame = $right_frame->Label->pack(-side => 'left', -ancho
+r => 'n', -expand => 1);
my $red_frame = $variable_frame->Label(-textvariable =>\$red)->pack(-s
+ide => 'top');
my $green_frame = $variable_frame->Label(-textvariable =>\$green)->pac
+k(-side => 'top');
my $blue_frame = $variable_frame->Label(-textvariable =>\$blue)->pack(
+-side => 'top');
Intialize();
MainLoop;
sub Intialize
{
    while(1)
    {
        $red  = floor(5*rand());
        $red_frame->update;
        sleep 1;
        $green = floor(5*rand()+10);
        $green_frame->update;
        sleep 1;
        $blue = floor(5*rand()+20);
        $blue_frame->update;
        sleep 1;
    }
}
[download]

How many frames to you believe you created? It's not as many as you think. The answer is 0.

Try this version.

#!/usr/bin/perl

use strict;
use warnings;
use Tk;
use POSIX;
my $red;
my $green;
my $blue;
my $mw = MainWindow->new;
$mw->geometry('300x300');
$mw->title('Raw Renamer');

my $right_frame = $mw->Frame->pack(-side => 'left',
                                   -anchor => 'n',
                                   -expand => 1);
my $text_label = $right_frame->Label->pack(-side => 'left',
                                           -anchor => 'n',
                                           -expand => 1);

$text_label->Label(-text =>"Red")->pack(-side => 'top',
                                        -anchor => 'w');
$text_label->Label(-text =>"Green")->pack(-side => 'top',
                                          -anchor => 'w');
$text_label->Label(-text =>"Blue")->pack(-side => 'top',
                                         -anchor => 'w');

my $variable_frame = $mw->Frame->pack(-side => 'left',
                                               -anchor => 'n',
                                               -expand => 1);

my $red_label  = $variable_frame->Label(-textvariable =>\$red)->pack(-
+side => 'top');
my $green_label = $variable_frame->Label(-textvariable =>\$green)->pac
+k(-side => 'top');
my $blue_label  = $variable_frame->Label(-textvariable =>\$blue)->pack
+(-side => 'top');

Intialize();
MainLoop;

sub Intialize
{
    while(1)
    {
        $red  = floor(5*rand());
        $red_label->update;
        sleep 2;
        $green = floor(5*rand()+10);
        $green_label->update;
        sleep 2;
        $blue = floor(5*rand()+20);
        $blue_label->update;
        sleep 2;
    }
}
[download]

Excellent! I copied some old code for TK formatting and didn't change those labels to frames. Thank you very much!