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Topic: question about mdct and short windows (Read 1508 times) previous topic - next topic
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question about mdct and short windows

hi,

I'm using libmad to perform some compressed-domain audio analysis. I get the mdct after the reordering (i.e. after the call to the function III_reorder) from vector xr in the function mad_error III_decode of the file layer3.c. This vector seems to always contain the 576 values of the mdct ordered by frequency, as expected for long windows. This seems to be true even for short windows (when blocktype = 2). Are the three 192-points mdct computed in the case of short windows recombined in a 576-points mdct? How? If not, what do the 576 points in xr represent in the case of short windows?

thanks

jul