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i may sound too rookie please excuse me. When i read a .AAC audio file in Matlab using the audioread function the out put is a 256000x6 matrix. how do i know what is the content of each column?

filename = 'sample1.aac'; [y,Fs] = audioread(filename,'native');

writing the first column using audiowrite as below i can hear the whole sound. so what are the other columns?

audiowrite('sample2.wav',y,Fs);

zahraesb
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    from documentation `y`:"Audio data in the file, returned as an m-by-n matrix, where m is the number of audio samples read and n is the number of audio channels in the file." – Ander Biguri Feb 16 '17 at 14:44

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Documentation:

https://uk.mathworks.com/help/matlab/ref/audioread.html

Output Arguments

y - Audio Data

Audio data in the file, returned as an m-by-n matrix, where m is the number of audio samples read and n is the number of audio channels in the file.

If you can hear the entire file in the first channel, it just means most of that file is contained in a mono channel. From Wikipedia r.e. AAC audio channels:

AAC supports inclusion of 48 full-bandwidth (up to 96 kHz) audio channels in one stream plus 16 low frequency effects (LFE, limited to 120 Hz) channels, up to 16 "coupling" or dialog channels, and up to 16 data streams

https://en.wikipedia.org/wiki/Advanced_Audio_Coding

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Wolfie
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