TH25554A - Methods and equipment for encoding/decoding audio? - Google Patents

Abstract

The methods and devices used for encoding and/or decoding audio components in an encoder and/or decoding speech based on a digital frame in which a signal source is connected to a filter, such filter is defined (12) by a set of filter parameters for each frame to reconstruct the signal to be encoded and/or decoded, which consists of a step of measurement (16) to see if the signal sent to the encoder/decoder represents or is fundamentally an audio component or speech, and when such a signal represents or is fundamentally an audio component, control (18) the transient variation between consecutive frames and/or range of at least some filter parameters in the set.

Claims (10)

1. The method of encoding and/or decoding audio in a speech encoder and/or decoder that uses a digital frame as a basis, which includes a source signal connected to a filter, where such filter is defined by a set of parameters for each frame in order to reconstruct the contract to be encoded and/or decoded. Such method consists of the steps of (a) detecting whether the signal sent to the encoder/decoder fundamentally represents or does not represent audio or speech, and (b) when the signal sent to the encoder/decoder fundamentally represents or does not represent audio, it enforces transient variations between consecutive frames and/or ranges of at least one filter that defines parameters in that set. 2. The method described in Claim 1, where transient variations of a parameterized filter are controlled by a low-pass filter across multiple frames. 3. The method specified in claim 2, where the transient variation of a parameterized filter is controlled by averaging the parameterized filter values across multiple frames. 4. A method as specified in any one of Claims 1, 2, or 3, whereby the range of the filter with defined parameters is adjusted to shift the filter's polarity closer to the beginning of the mixing plane. 5. The method described in any of the preceding claims, where the signal received by such source and filter, together with the adjusted parameters, is further adjusted by the after-filter so as not to specify the frequency range therein. 6. Devices for encoding and/or decoding audio components in a speech encoder and/or decoder based on a digital frame, including a source signal connected to a filter, where the filter is defined by a set of parameters for each frame to reconstruct the signal to be encoded and/or decoded. Such device includes (a) pathways (16, 34) for detecting whether the signal sent to the encoder/decoder represents or is not speech or audio components, and (b) pathways (18, 36) for controlling the transient variation between consecutive frames and/or ranges of at least one filter that defines parameters in the set when the signal sent to the encoder/decoder is fundamentally speech or audio components. 7. An apparatus as specified in claim 6 in which the transient variation of a parameterized filter is controlled by a low-pass filter (54) that filters the parameterized filter across multiple frames. 8. An apparatus as specified in claim 7 where transient variation of a parameterized filter is controlled by a low-pass filter that averages the parameterized filter across multiple frames. 9. An apparatus as specified in any of Claims 6, 7 or 8 in which the range of the filter given the parameters is adjusted in a path (52) that shifts the filter poles closer to the starting point of the mixing plane. 10. Any device as specified in claims 6-9 where the signal received by such source and filter, together with its adjusted parameters, is further adjusted by the filter (44) to break down the frequency definition specified therein (Clause 10, page 2, figure 6).