Signal Decoding Apparatus

• US 20090006086A1
• Filed: 07/25/2005
• Published: 01/01/2009
• Est. Priority Date: 07/28/2004
• Status: Active Grant

• Current Assignee: III Holdings 12, LLC (Intellectual Ventures LLC)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Morii, Toshiyuki, Sato, Kaoru, Yamanashi, Tomofumi
• Granted Patent: US 8,099,291 B2
• Time in Patent Office: Days
• US Class Current: 704/225
• CPC Class Codes: G10L 19/005 Correction of errors induced by the transmission channel, if related to the coding algorithm
• CPC Class Codes: G10L 19/24 Variable rate codecs, e.g. for generating different qualities using a scalable representation such as hierarchical encoding or layered encoding

Abstract

A signal decoding apparatus that can suppress any large unusual sounds to provide decoded signals of improved audibility even when the number of hierarchical layers to be used in the decoding process varies due to a packet loss or the like in communication utilizing a scalable encoding/decoding technique. In the signal decoding apparatus, a gain adjusting part (2308) adjusts, based on a control of a decoding control part (2301), the gain of a basic layer decoded signal outputted from a basic layer decoding part (2302). A gain adjusting part (2309) adjusts, based on a control of the decoding control part (2301), the gain of a first expansion layer decoded signal outputted from a first expansion layer decoding part (2303). A gain adjusting part (2310) adjusts, based on a control of the decoding control part (2301), the gain of a second expansion layer decoded signal outputted from a second expansion layer decoding part (2304).

Claims

1. A signal decoding apparatus that decodes coded information constructed in a plurality of layers, comprising:

a decoding section that decodes the coded information of each layer and generates a plurality of decoded signals;

an addition section that adds each said decoded signal and generates an addition signal;

a gain adjustment section that adjusts the gain of said addition signal; and

a control section that controls the gain width of said gain adjustment section based on the presence or non-presence of coded information of each layer of the previous and next frames.

2. A signal decoding apparatus that decodes coded information constructed in a plurality of layers, comprising:

a decoding section that decodes the coded information of each layer and generates a plurality of decoded signals;

a plurality of sampling adjustment sections that adjust the sampling frequency of each said decoded signal;

an addition section that adds each said decoded signal after said sampling adjustment and generates an addition signal;

a gain adjustment section that adjusts the gain of said addition signal; and

a control section that controls the gain width of said gain adjustment section based on the presence or non-presence of coded information of each layer of the previous and next frames.

3. A signal decoding apparatus that decodes coded information constructed in a plurality of layers, comprising:

a decoding section that decodes the coded information of each layer and generates a plurality of decoded signals;

an addition section that adds each said decoded signal and generates an addition signal;

a storage section that stores the addition signal after gain adjustment of the previous frame;

a synthesis processing section that synthesizes the addition signal of the previous frame stored in said storage section and the addition signal of the current frame added by said addition section; and

a control section that controls whether or not synthesis processing by said synthesis processing section is to be performed based on the presence or non-presence of coded information of each layer of the previous frame.

4. The signal decoding apparatus according to claim 3, comprising a gain adjustment section that adjusts the gain of said addition signal, wherein said control section controls the gain width of said gain adjustment section based on the presence or non-presence of coded information of each layer of the previous frame.