Still, using binary data seems to be faster: 
use Tk;
use Benchmark qw(cmpthese);
use MIME::Base64 qw(encode_base64);
use LWP::Simple qw(get);

my $mw = tkinit;
my $file = Tk->findINC("Xcamel.gif");
my $data = get "file://$file"; # poor man's File::Slurp

cmpthese(-1,
     { base64 => sub {
           my $p = $mw->Photo(-data => encode_base64($data));
           $p->delete;
       },
       binary => sub {
           my $p = $mw->Photo(-data => $data);
           $p->delete;
       }
     }
    );

[download]
The result is: 
$ perl5.9.5d -Mblib=/home/e/eserte/work/svk-checkouts/Tk-debug ~/trash
+/imgbench.pl
        Rate base64 binary
base64 574/s     --   -38%
binary 926/s    61%     --

[download]
I agree that the performance gain would be larger if no (unnecessary) conversion to utf-8 would occur at all. Maybe it's somehow possible to prevent this, for example by using a special reference or magics for the value of -data, which wouldn't be upgraded by Tcl_GetString calls.

But I think I have first to learn how the Perl/Tk internals work at all...

In reply to Re^6: Tk:Photo -data with binary data? by eserte
in thread Tk:Photo -data with binary data? by BrowserUk

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