Download datasets

很贴心，MATLAB访问代码：

% This function reads a siftgeo binary file
%
% Usage: [v, meta] = siftgeo_read (filename, maxdes)
%   filename    the input filename
%   maxdes      maximum number of descriptors to be loaded
%   (default=unlimited)
%
% Returned values
%   v           the sift descriptors (1 descriptor per line)
%   meta        meta data for each descriptor, i.e., per line:
%               x, y, scale, angle, mi11, mi12, mi21, mi22, cornerness
function [v, meta] = siftgeo_read (filename, maxdes)

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