Mostly just style choices but in lines like this:

if(/^(.+)\s(http:\/\/\S+)\s*(.+)$/){
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I would use an alternate regex delimiter, maybe "#":

if ( m#^(.+)\s(http://\S+)\s*(.+)$# ) {
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and in this:

$http->body()=~/<\s*img[^>]*src\s*=\s*[\'\"]([^\'\"]+)[\'\"
+][^>]*$ALT/i
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You don't need to backwhack the quotes inside the character classes. In fact, I think the only character you need to backslash inside the '[]' brackets is a backslash.

my ($dimention);
for $dimention ('-width','-height'){
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the above is more perlish (and dimention is more correctly spelled) as:

for my $dimension ( qw(-width -height) ) {
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You have my ($var)= ... all over when you really mean my $var = .... The difference is whether the expression on right side of the '=' is in list or scalar context. It often doesn't matter, but someday you may be bitten by this.

Last, there doesn't seem to be any reason not to Use strict and warnings.