% MAKE_NOISY_DATA Adds Gaussian noise to USPS database.%% Description:%  It adds Gaussian noise to the USPS images. The input%  file usps.mat contains training trn.X and testing %  tst.X part. This script generates file usps_noisy%  which contains%    trn.gnd_X [256x7291] Original training USPS data.%    trn.X     [256x7291] USPS data with added Gaussian noise.%    trn.y     [1x7291] Labels (1..10).%%    tst.gnd_X [256x2007] Original testing USPS data.%    tst.X     [256x2007] USPS data with added Gaussian noise.%    tst.y     [1x2007] Labels (1..10).%    % About: Statistical Pattern Recognition Toolbox% (C) 1999-2003, Written by Vojtech Franc and Vaclav Hlavac% <a href="http://www.cvut.cz">Czech Technical University Prague</a>% <a href="http://www.feld.cvut.cz">Faculty of Electrical Engineering</a>% <a href="http://cmp.felk.cvut.cz">Center for Machine Perception</a>% Modifications:% 07-jun-2004, VF% setting%---------------------------------------------% signal to noise ratiosnr = 1;input_data_file = '/home.dokt/xfrancv/data/usps/usps.mat';output_data_file = '/home.dokt/xfrancv/data/usps/usps_noisy.mat';% load input fileorig = load(input_data_file);% add noisetrn.X = orig.trn.X + randn(size(orig.trn.X))*(std(orig.trn.X(:))/snr);trn.y = orig.trn.y;trn.gnd_X = orig.trn.X;tst.X = orig.tst.X + randn(size(orig.tst.X))*(std(orig.tst.X(:))/snr);tst.y = orig.tst.y;tst.gnd_X = orig.tst.X;% save it to filesave(output_data_file,'tst','trn');% EOF