Method and Apparatus for Obtaining Spectrum Coefficients for a Replacement Frame of an Audio Signal, Audio Decoder, Audio Receiver and System for Transmitting Audio Signals

Simple SummaryContent extracted from patent full text and abstract with AI.

This invention provides a method and apparatus for concealing lost or corrupted frames in coded audio signals during transmission. When a frame is missing, the system analyzes the frequency spectra of previous frames to detect tonal (musical/harmonic) components based on spectral peaks that persist over frames. For these tonal components, it predicts the missing spectral information in the lost frame using historical data and phase prediction. For other (non-tonal/noise) components, it uses either generated noise-like data or copies from earlier frames. The approach is designed to be low-latency and robust, handling both monophonic and polyphonic audio.

Use CasesContent extracted from patent full text and abstract with AI.

• Streaming audio applications (e.g., online music, podcasts) with potential packet loss or network errors
• Voice over IP (VoIP) and teleconferencing systems to maintain audio quality despite data loss
• Mobile communication devices prone to signal interruptions
• Broadcast audio decoders and receivers for digital radio or TV
• Professional audio transmission over unreliable or wireless links
• Any audio compression codec requiring frame-loss concealment, such as Bluetooth audio systems

BenefitsContent extracted from patent full text and abstract with AI.

• Improved audio quality during data loss or transmission errors, especially for music and tonal signals
• Reduced perceptual artifacts compared to simple frame repetition or muting
• No additional delay is introduced, maintaining low latency essential for communication and live applications
• Works with both speech and general audio (including polyphonic and tonal content)
• Adaptable to both time and frequency domain concealment based on signal characteristics
• Does not require extra side information or additional bandwidth, simplifying system design
• Efficient processing, allowing use in real-time and embedded applications

Technical Classifications (CPCs)

Inventors & Applicants

Patent Abstract

An approach is described that obtains spectrum coefficients for a replacement frame (m) of an audio signal. A tonal component of a spectrum of an audio signal is detected based on a peak that exists in the spectra of frames preceding a replacement frame (m). For the tonal component of the spectrum a spectrum coefficients for the peak (502) and its surrounding in the spectrum of the replacement frame (m) is predicted, and for the non-tonal component of the spectrum a non-predicted spectrum coefficient for the replacement frame (m) or a corresponding spectrum coefficient of a frame preceding the replacement frame (m) is used.