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

• US 8,239,193 B2
• Filed: 09/17/2009
• Issued: 08/07/2012
• Est. Priority Date: 01/12/2007
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Oh, Eun-mi, Choo, Ki-hyun, Kim, Jung-hoo
• Primary Examiner(s): YEN, ERIC L
• Application Number:
  US12/585,569
• Publication Number:
  US 20100010809A1
• Time in Patent Office: 1,055 Days
• Field of Search: 704/230, 704/219, 704/262, 704/269, 704/500, 704/225
• US Class Current: 704/219
• 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 signal has been encoded in a frequency domain or a time domain;

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

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

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

generating a high frequency band signal using the transformed signal;

generating a stereo signal from the high frequency band signal and the transformed signal; and

inverse-transforming the stereo signal using an inverse QMF.

2. A method of bandwidth extension decoding, comprising:

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

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

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

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

generating a high frequency band signal using the transformed signal;

generating an extended signal including the transformed signal and the high frequency band signal;

generating a stereo signal from the extended signal; and

inverse-transforming the stereo signal using an inverse QMF.