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0010 function [ImR] = jpeg91_decoder(directorio,fichero)
0011 Lb = 16;
0012 Li = 256;
0013
0014 cd(directorio)
0015 unzip([fichero '.zip']);
0016 ristra = read_code_jpeg91([fichero '.bin']);
0017
0018 delete([fichero '.bin']);
0019 TheCode = zeros(256,255);
0020
0021 norm = [3 ristra(1)];
0022 extr_err = ristra(2:3);
0023 QE = reshape(ristra(4:3+256),16,16);
0024 B = ristra(260);
0025
0026 ristra = ristra(261:end);
0027
0028 [TheCode] = inv_rle(ristra);
0029
0030 NumNiv = 2^B;
0031 MM = 0.8;
0032
0033 TheRealCode = TheCode * MM / NumNiv;
0034
0035 Nc = round(0.9 * 40);
0036 qe = (extr_err(2) - extr_err(1)) * QE / (Nc - 1) + extr_err(1);
0037
0038 Lmq = iimdpcm(qe,1,100);
0039
0040 fprintf('Recovering the image:\n');
0041 z = 1;
0042 dctc1 = zeros(Li,Li);
0043 for i = 1:Lb:(Li-1)
0044 for j = 1:Lb:(Li-1)
0045
0046 b = TheRealCode(z,:)';
0047 b = [0; b];
0048 b = dezigzag(b);
0049
0050 dctc1(i:(i+(Lb-1)),j:(j+(Lb-1))) = b;
0051 z = z + 1;
0052 end
0053 end
0054
0055 dctc1i = icontra2(dctc1,Lmq,4,norm);
0056
0057 ImR = real(idct2r(dctc1i,4));