accumulate dec stat
fix crash issue of sliceskip and inf-loop in fmo
Merge pull request #1589 from huili2/fix_fmo_sliceskip

fix crash issue of sliceskip and inf-loop in fmo
Merge pull request #1588 from huili2/dec_stat_accumulate

accumulate dec stat
fix grey picture when resolution is the same
Merge pull request #1592 from dongzha/FixGreyPic

fix grey picture when resolution is the same
Merge remote-tracking branch 'upstream/master' into travis.osx