It makes sense what you said, but the issue is on these lines

        if(($row->{image_name_1} ne "") eq ($pics[0] ne "")){$flag_pic
++=1;}
        if(($row->{image_name_2} ne "") eq ($pics[1] ne "")){$flag_pic
++=1;}
        if(($row->{image_name_3} ne "") eq ($pics[2] ne "")){$flag_pic
++=1;}
        if(($row->{image_name_4} ne "") eq ($pics[3] ne "")){$flag_pic
++=1;}
[download]

It is not considering the equality, even if the images are not a match it is still incrementing $flag_pic+=1.