[Mp4-tech] AAC Decoder Query

[sakthi narayanan]

Hi all,
  I want to know some inforamtion regarding abt aac decoder.
How the aac decoder is decoding the input
raw aac bitstream for the wrong sampling frequency.I observed 
that,for some sampling frequncy its throwing 
error and for some sampling frequency is decoding the bitstream 
successfully.
for eg,take a 12kHz encoded bitstream as a input for the aac 
decoder.The 12khz encoded input bitstream is 
able to decoded with the sampling frequency of 11khz,16Khz.For other 
sampling frequency range,
its throwing an error.this is happening,because of scalefactor 
band.Can u tell me ,how its working for all other
sampling frequency.
And,how to get the sampling frequency information from the encoded 
raw bitstream.If its an adts aac bitstream,
we can get the sampling frequency information from the adts header.In 
case of raw bitstream,how to get the sampling
frequency from the input bitstream.If you are setting wrong sampling 
frequency(take 11khz) for the 22khz 
encoded bitstream,the decoder either will throw you the error or 
decoded successfully.
With Regards,
sakthi
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