Question: In the Enhanced Voice Services (EVS) codec, what is the primary purpose of transmitting concealment/recovery parameters as side information to the decoder?
Option 1: To reduce the overall bitrate in voice transmissions
Option 2: To enhance the security of voice communications by encrypting sensitive data
Option 3: To improve the efficiency of the safety-net approach for LSF quantization
Option 4: To enhance frame erasure concealment (FEC) and aid decoder convergence after erased frames
Explanation: The correct answer is Option 4 because transmitting concealment/recovery parameters as side information in codecs like EVS primarily aims to mitigate the effects of frame erasures, helping the decoder effectively conceal errors and quickly recover from lost frames for better voice quality under adverse network conditions.