fisher vector學習筆記:http://blog.csdn.net/happyer88/article/details/46576379
fisher vector改進:http://blog.csdn.net/happyer88/article/details/46625639
使用vlfeat提取fisher vector的matlab 代碼
% 讀入圖片
I = vl_impattern('roofs1') ;
I = single(vl_imdown(rgb2gray(I))) ;
% 設置bin大小
binSize = 8 ;
% sparse sift中bin大小是根據該層的高斯平滑的尺度sigma計算來的
% dense sift這裏是設定binSize,反推sigma
magnif = 3 ;
% 對圖像做高斯平滑
Is = vl_imsmooth(I, sqrt((binSize/magnif)^2 -