修正blockDiffMap计算
修正blockDiffMap计算

ianhuang-777/guetzli,guanzidashu/guetzli_ios_metal,guanzidashu/guetzli_ios_metal,guanzidashu/guetzli_ios_metal,guanzidashu/guetzli_ios_metal,ianhuang-777/guetzli,ianhuang-777/guetzli,ianhuang-777/guetzli