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Hydrogenaudio Forums > Lossy Audio Compression > AAC > AAC - Tech
shreya_pathak
Hi,
In Mpeg4 AAC decoder publicly available code from Nero i.e FAAC,
in file decoder.c

if (hDecoder->frame <= 1)
hInfo->samples = 0;
They are skipping the first frame.
I didn't get why they are skipping the first frame.
Regards
Shreya
sospee
Shreya,hi,
If you explore some details of Transform Audio Coding with overlap-add technique.
(use MDCT or other transforms i.e. DFT), it is neccessary to skip 1st audio frame (actually 1st half window). Because this "frame" doesn't do any lap with following
analysis windows.

--sospee
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