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function x = iAACoder2(AACSeq2, fNameOut)
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%Implementation of AAC decoder
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% Usage x = iAACoder2(AACSeq2, fNameOut), where:
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% Inputs
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% - fNameOut is the filename and path of the file that will be
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% written after decoding
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% - AACSeq2 is an array of structs containing K structs, where K is
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% the number of computed frames. Every struct of the array consists
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% of a frameType, a winType, chl.TNScoeffs which are the quantized TNS
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% coefficients of this frame's left channel, chr.TNScoeffs which are
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% the quantized TNS coefficients of this frame's right channel,
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% chl.frameF which are the MDCT coefficients of this frame's left
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% channel, chr.frameF which are the MDCT coefficients of this frame's
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% right channel
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%
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% Output
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% - x is an array containing the decoded audio samples
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% Initializes an array to hold the decoded samples
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decodedAudio(1024 * (length(AACSeq2) + 1), 2) = 0;
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% Initializes an array to hold both audio channels
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frameF(1024, 2) = 0;
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% Decodes audio file
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for i = 0:length(AACSeq2) - 1
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currFrameStart = i * 1024 + 1;
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currFrameStop = currFrameStart + 2047;
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frameF(:, 1) = AACSeq2(i+1).chl.frameF;
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frameF(:, 2) = AACSeq2(i+1).chr.frameF;
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TNScoeffsL = AACSeq2(i + 1).chl.TNScoeffs;
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TNScoeffsR = AACSeq2(i + 1).chr.TNScoeffs;
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frameF(:, 1) = iTNS(frameF(:, 1), AACSeq2(i+1).frameType, TNScoeffsL);
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frameF(:, 2) = iTNS(frameF(:, 2), AACSeq2(i+1).frameType, TNScoeffsR);
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frameT = iFilterbank(frameF, AACSeq2(i+1).frameType, AACSeq2(i+1).winType);
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decodedAudio(currFrameStart:currFrameStop, :) = decodedAudio(currFrameStart:currFrameStop, :) + frameT;
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end
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audiowrite(fNameOut, decodedAudio, 48000);
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x = decodedAudio;
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end
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