2012-10-25convert mogrify 给图片添加水印
mogrify -font ss.ttf -pointsize 24 -fill #ffffff -weight bloder -gravity southeast -annotate +30+30 "www.dsppa.com"
mogrify -font ss.ttf -pointsize 24 -fill #ffffff -weight bloder -gravity southeast -annotate +30+30 @"ss"