Yes, I've tried that too. The following example works if you switch the comment cards to encode the data base64, but not without. I've also tried various different formats that GD support (.jpg, .gif). The result is always couldn't recognize image data at c:/Perl/site/lib/Tk/Image.pm line 21, which is annoying because it can read that same data back from a file, with or without a format hint.

It seems strange that is can read the data from a file, but not directly from memory. If the -file option would take a file handle instead of a name, I could throw the data into a ramfile, but it doesn't :(

The time taken to convert the image to base64 to pass it into tk--where it is presumably converted straight back again--thrashes the cpu to death and really slows things down of you are trying to update the image quickly.

#! perl -slw
use strict;
use Tk;
use Tk::PNG;
use GD::Graph;
use GD::Graph::bars;
use MIME::Base64 qw[ encode_base64 ];

my $data = [
   [qw/1st 2nd 3rd 4th 5th 6th 7th 8th 9th/],
   [qw/  1   2   5   6   3 1.5   1   3   4/],
];

my $graph = GD::Graph::bars->new(400, 300);
$graph->set(
   x_label        => 'X Label',
   y_label        => 'Y label',
   title          => 'Some simple graph',
   y_max_value    => 8,
   y_tick_number  => 8,
   y_label_skip   => 2
) or die $!;

my $gd = $graph->plot($data) or die $!;

my $mw = MainWindow->new;
my $png = $mw->Photo(
#    -data => encode_base64( $gd->png ),
    -data =>  $gd->png,
    -format => 'png'
);

my $btn = $mw->Button( -text => 'doit', -command => sub{
    $data->[ 1 ] = [ map{ rand 5 } 1 .. 9 ];
    undef $graph;
    $graph = GD::Graph::bars->new(400, 300);
    $graph->set(
       x_label        => 'X Label',
       y_label        => 'Y label',
       title          => 'Some simple graph',
       y_max_value    => 8,
       y_tick_number  => 8,
       y_label_skip   => 2
    ) or die $!;

    my $gd = $graph->plot($data) or die $!;
    $png->blank;
    $png->configure(
#        -data  => encode_base64( $gd->png ),
        -data  => $gd->png,
        -format => 'png'
    );
    $mw->update;
} )->pack;

$mw->Label(-image => $png)->pack;

$mw->repeat( 1000, sub{ $btn->invoke; $png->update } );
MainLoop;

__END__
couldn't recognize image data at c:/Perl/site/lib/Tk/Image.pm line 21.
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