Method, apparatus, and medium for bandwidth extension encoding and decoding

• US 20100010809A1
• Filed: 09/17/2009
• Published: 01/14/2010
• Est. Priority Date: 01/12/2007
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Jung-hoo, Choo, Ki-hyun, Oh, Eun-mi
• Granted Patent: US 8,239,193 B2
• Time in Patent Office: Days
• US Class Current: 704/206
• CPC Class Codes: G10L 19/0212 using orthogonal transformation
• CPC Class Codes: G10L 19/12 the excitation function being a code excitation, e.g. in code excited linear prediction [CELP] vocoders
• CPC Class Codes: G10L 19/20 using sound class specific coding, hybrid encoders or object based coding
• CPC Class Codes: G10L 21/038 using band spreading techniques

Abstract

Provided are a method, apparatus, and medium for encoding/decoding a high frequency band signal by using a low frequency band signal corresponding to an audio signal or a speech signal. Accordingly, since the high frequency band signal is encoded and decoded by using the low frequency band signal, encoding and decoding can be carried out with a small data size while avoiding deterioration of sound quality.

Claims

1. A method of bandwidth extension decoding, comprising:

checking whether a band limited signal has been encoded in a frequency domain or a time domain;

performing lossless decoding and de-quantization, controlling noise, and inverse-transforming the band limited signal to the time domain if the checking result shows that the band limited signal has been encoded in the frequency domain;

performing decoding using CELP (code excited linear prediction) if the checking result shows that the band limited signal has been encoded in the time domain;

transforming the signal inverse-transformed to the time domain or the signal decoded using CELP using a quadrature mirror filterbank (QMF);

decoding a high frequency band signal using the transformed signal; and

inverse-transforming the decoded signal using the QMF.

2. A method of bandwidth extension decoding, comprising:

checking whether a band limited signal has been encoded in a frequency domain or a time domain;

performing lossless decoding and de-quantization, controlling noise, and inverse-transforming the band limited signal to the time domain if the checking result shows that the band limited signal has been encoded in the frequency domain;

performing decoding using CELP (code excited linear prediction) if the checking result shows that the band limited signal has been encoded in the time domain;

transforming the signal inverse-transformed to the time domain or the signal decoded using CELP;

decoding a high frequency band signal using the transformed signal;

combining either the signal inverse-transformed to the time domain or the signal decoded using CELP and the decoded high frequency band signal; and

inverse-transforming the combined signal.