Reconstructing AAC CPE

Part of Understanding AAC

This page describes the process of reconstructing PCM data based on the decoded CPE parameters in an AAC bitstream. For the moment, this description focuses on what is necessary to reconstruct low complexity (LC) profile data.

Reconstruction Process

 specrec.c:reconstruct_channel_pair()
    -specrec.c:allocate_channel_pair()
    -specrec.c:inverse_quantization()
    -specrec.c:apply_scalefactors()
    -specrec.c:quant_to_spec()
    -pns.c:pns_decode()
      -pns.c:generate_random_vector()
    -ms.c:ms_decode()
    -is.c:is_decode()
    -ic_predict.c:ic_prediction() (main profile)
    -ic_predict.c:pns_reset_pred_state() (main profile)
    -(processing that is specific LTP