AUDIO ENCODER AND DECODER FOR ENCODING FRAMES OF SAMPLED AUDIO SIGNALS

摘要

AN AUDIO ENCODER (100) ADAPTED FOR ENCODING FRAMES OF A SAMPLED AUDIO SIGNAL TO OBTAIN ENCODED FRAMES, WHEREIN A FRAME COMPRISES A NUMBER OF TIME DOMAIN AUDIO SAMPLES, COMPRISING A PREDICTIVE CODING ANALYSIS STAGE (110) FOR DETERMINING INFORMATION ON COEFFICIENTS OF A SYNTHESIS FILTER AND INFORMATION ON A PREDICTION DOMAIN FRAME BASED ON A FRAME OF AUDIO SAMPLES. THE AUDIO ENCODER (100) FURTHER COMPRISES A FREQUENCY DOMAIN TRANSFORMER (120) FOR TRANSFORMING A FRAME OF AUDIO SAMPLES TO THE FREQUENCY DOMAIN TO OBTAIN A FRAME SPECTRUM AND AN ENCODING DOMAIN DECIDER (130) FOR DECIDING WHETHER ENCODED DATA FOR A FRAME IS BASED ON THE INFORMATION ON THE COEFFICIENTS AND ON THE INFORMATION ON THE PREDICTION DOMAIN FRAME, OR BASED ON THE FRAME SPECTRUM.MOREOVER, THE AUDIO ENCODER (100) COMPRISES A CONTROLLER (140) FOR DETERMINING AN INFORMATION ON A SWITCHING COEFFICIENT WHEN THE ENCODING DOMAIN DECIDER DECIDES THAT ENCODED DATA OF A CURRENT FRAME IS BASED ON THE INFORMATION ON THE COEFFICIENTS AND THE INFORMATION ON THE PREDICTION DOMAIN FRAME WHEN ENCODED DATA OF A PREVIOUS FRAME WAS ENCODED BASED ON A PREVIOUS FRAME SPECTRUM AND A REDUNDANCY REDUCING ENCODER (150) FOR ENCODING THE INFORMATION ON THE PREDICTION DOMAIN FRAME, THE INFORMATION ON. THE COEFFICIENTS, THE INFORMATION ON THE SWITCHING COEFFICIENT AND/OR THE FRAME SPECTRUM.