perl -le '@times=qw(5:29,11 29,11 29 ,11 5:29 abc);
foreach my $time (@times){
 if($time!~/[0-9:,]+/) {$seconds=-1}
else { ($seconds=$time)=~s{^(?:(\d+):)?(\d+)?(?:,(\d+))?$}{$1*60+$2+$3
+/10**2}e;}
print $seconds}'

329.11
29.11
29
0.11
329
-1
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