use strict;
use warnings;

while (my $line = <DATA>)
{
    chomp $line;
    my @cols  = split /,/,  $line;
    my @third = split /\./, $cols[2];

    print join(',', @cols), "\n" if @third < 3;
}

__DATA__
cls1,37,Media.vdenc.abcunit,media_vd
cls2,7,Media.Wigig.plsunit,media_vd
cls3,27,Media.vdenc,media_vd
cls4,47,Media.hevc,media_vd
cls5,57,Media.ENC,media_vd