MULTIPLEXED AUDIO DATA DECODING APPARATUS AND RECEIVER APPARATUS

• US 20090024400A1
• Filed: 09/23/2008
• Published: 01/22/2009
• Est. Priority Date: 11/04/1998
• Status: Active Grant

• Current Assignee: Maxell, Ltd.
• Original Assignee: Hitachi, Ltd., Hitachi Video & Information System Incorporated
• Inventors: YAMAMOTO, EIJI, FUJII, YUKIO, OBATA, SHINICHI, SHIRANE, HIROAKI
• Granted Patent: US 8,098,695 B2
• Time in Patent Office: Days
• US Class Current: 704/500
• CPC Class Codes: G11B 20/10527 Audio or video recording; Data buffering arrangements G11B20/12 - G11B20/18 take precedence
• CPC Class Codes: H04N 21/2368 Multiplexing of audio and video streams
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/42615 involving specific demultiplexing arrangements
• CPC Class Codes: H04N 21/42692 for reading from or writing on a volatile storage medium, e.g. Random Access Memory [RAM]
• CPC Class Codes: H04N 21/434 Disassembling of a multiplex stream, e.g. demultiplexing audio and video streams, extraction of additional data from a video stream; Remultiplexing of multiplex streams; Extraction or processing of SI; Disassembling of packetised elementary stream demultiplexing of data packets for data networks, e.g. RTP/UDP H04L65/00
• CPC Class Codes: H04N 21/4341 Demultiplexing of audio and video streams
• CPC Class Codes: H04N 21/435 Processing of additional data, e.g. decrypting of additional data, reconstructing software from modules extracted from the transport stream
• CPC Class Codes: H04N 21/4384 involving operations to reduce the access time, e.g. fast-tuning for reducing channel switching latency
• CPC Class Codes: H04N 21/4392 involving audio buffer management
• CPC Class Codes: H04N 5/50 Tuning indicators; Automatic tuning control

Abstract

A multiplexed audio data decoder apparatus is provided in which integration of an audio decoder is easy, and has a high flexibility when the number of the formats to be processed is increased or when the specification is changed. In an external ROM 60 there are accumulated a plurality of decoding program codes corresponding to respective plural methods for compressing and encoding. A controller means 50 transfers the decoding program code corresponding to the method for compressing and encoding after changing thereof, from the external ROM 60 to an internal RAM 25. A DSP 22 starts decoding processing by using the decoding program code which is transmitted into the internal RAM 25.

Claims

1. A multiplexed audio data decoder apparatus, for inputting a group of packets, each being formed by packetizing audio data sequences which are compressed and encoded and by multiplexing a plurality of those sequences, and for selectively decoding one audio data sequence which is designated by a user, comprising:

a demultiplexer for extracting the one audio data sequence which is designated by the user from said group of packets depending upon a property or attribute information which each packet has, and further for extracting a method of the compression and encoding which is applied for compressing the audio data sequence from a header information which said each audio data sequence has;

a first memory in which decoding process codes corresponding to said method of the compression and encoding;

a digital signal processor for decoding the compressed audio data sequences in accordance with said decoding process codes, sequentially;

a read-only memory, in which are accumulated a plurality of the decoding process codes, each corresponding to each one of said plural methods of the compression and encoding; and

controller means for detecting change in said method of the compression and encoding, and for transferring the decoding process code corresponding to the method of the compression and encoding after being changed, from said read-only memory to said first memory, wherein

said digital signal processor begins decoded process by using the decoding process code which is transferred to said first memory.