Question: In EVS (Enhanced Voice Services) codec, as per 3GPP standards, why is interpolation for obtaining LP parameters for each subframe performed on LSP (Line Spectral Pairs) parameters instead of directly on LP (Linear Prediction) parameters?
Option 1: To reduce computational complexity in the conversion process.
Option 2: Due to stability issues associated with interpolating LP parameters directly.
Option 3: To enhance the precision of quantized LSPs in the interpolation process.
Option 4: For compatibility with legacy voice codecs that utilize LSP parameters.
Explanation: Interpolating directly on LP parameters can lead to stability issues, which could compromise the quality and integrity of the voice service. By converting to LSP parameters for interpolation and then back to LP domain, the EVS codec ensures a more stable and reliable operation, maintaining the enhanced voice quality as intended by the 3GPP standards.