Home | Links | Contact Us | More About Intellectual Property | Bookmark

Search patents:

Home

File Sharing

Apparatus-for-compressing-audio-data

Method and apparatus for value-based queuing of telephone calls

Accordingly, it is an object of this invention to provide a phone queuing system and method which ...

Providing transaction undo without logging

To overcome the limitations in the prior art described above, and to overcome other limitations ...

Database network connectivity product

The present invention overcomes the problems and disadvantages of the prior art by providing a "...

Summary table management in a computer system

OF THE PREFERRED EMBODIMENTS In the following description, for purposes of explanation, numerous ...

Decision analysis system and method

OF THE INVENTION A digital computer system using the method and apparatus described herein, ...

Page open/close scheme based on high order address bit and likelihood of page access

When writing a computer program which accesses a page of memory a programmer may know whether the ...

System for managing direct memory access transfer in a multi-channel system using circular descriptor queue, descriptor FIFO, and receive status queue

There is a need for a method and apparatus that provides an efficient management of data transfers ...

Dynamic allocation for efficient management of variable sized data within a nonvolatile memory

In view of limitations of known systems and methods, a plurality of storage structures are provided ...

Network-based conference system

According to the present invention, there is provided a management and control unit for a network-...

Method and apparatus for partitioned based purging of data

The present methods and systems purge selected change data from a named change data database table ...

Apparatus for compressing audio data

Details

Inventors: Fukuchi, Hiroyuki;
Assignee: Nippon Steel Corporation (Tokyo, JP)
Primary Examiner: Hudspeth; David R.
Assistant Examiner: Abebe; Daniel
Attorney, Agent or Firm: Pollock, Vande Sande & Amernick

An apparatus for compressing audio data is provided. An audio signal is sampled and divided into divided audio signals in a plurality of frequency bands. A predetermined process is applied to ones respective of the divided audio signals and a characteristic value for each of the divided audio signals is calculated after the predetermined process. An adaptive bit allocation circuit repeatedly allocates a number of bits to each of the divided audio signals based on the characteristic value and a bit rate of the input audio signal. The adaptive bit allocation circuit detects the frequency band containing one of the divided audio signals having a maximum characteristic value within a selected frequency range. A unit number of bits is repeatedly allocated to the one of the divided audio signals and the characteristics value is modified based on the unit number of bits. A counting member counts the number of allocated bits for the one of the divided audio signals. A detection range control member selects the frequency range used in the detection process in accordance with the bit rate of the input audio signal and the number of allocated bits that have been counted.

DETAILED DESCRIPTION It is an object of the present invention to provide an apparatus for compressing audio data which can suppress the undue increase of the processing time when the bit rate to be used for the quantization of the audio data is high.
According to one aspect of the present invention, the apparatus for compressing audio data comprises means for sampling an input digital audio signal at a predetermined sampling period and transforming the sampled digital audio signal into a plurality of frequency band signals.
Means are provided for each of the frequency band signals for applying a predetermined process to the audio signal contained in the corresponding band.
A circuit for calculating a signal characteristic for each of the audio signals contained in each of the frequency bands, and an adaptive bit allocation circuit for allocating bits to be used to represent each of the processed audio signals contained in each of the frequency bands based on a predetermined bit rate are provided.
The adaptive bit allocation circuit includes means for detecting one of the frequency bands containing one of the audio signals having a maximum characteristic value when the audio signals are represented by particular characteristic values, means for allocating a unit bit to each audio signal contained in the one frequency band, means for modifying the audio signal contained in the one frequency band, means for repeatedly activating the means for detecting one of the frequency bands, the means for allocating a unit bit and the means for modifying the audio signal based on the modified audio signal, count means for counting the number of times of repetition by the means for repeatedly activating, and means for controlling a band range of detection by the means for detecting one of the frequency bands based on the count of the count means.
In a preferred embodiment of the present invention, the signal characteristic calculation circuit includes a first circuit for calculating the signal characteristic in accordance with a first predetermined process, a second circuit for calculating the signal characteristic in accordance with a second predetermined process and switching means for selectively activating the first circuit and the second circuit in accordance with a bit rate

Related patents

	Fuzzy database retrieval A method for querying metadata associated with media on a computer network includes separating the metadata into keywords. The keywords are compared with valid keywords. ...
	Rating and controlling access to emails In view of the foregoing background, one object of the present invention is to enable parents or guardians to exercise some control over the web page content displayed ...
	Systems and methods for uniformly identifying e-mail attachments The document creator applications, e-mail software, communication software, and mobile information device-resident browsers come from various suppliers. Existing methods ...
	Summarized application profiling and quick network profiling The present invention pertains to profiling of application programs and computer networks. An automatic distributed partitioning system (ADPS) profiles an application ...
	Method for document comparison and selection One characteristic of the LSI technique is that it does not take into account term order. Each document is considered as a collection of unordered terms. It is known, ...
	Method and system for using virtual labels in a software configuration management system The present invention provides a solution to the needs described above through a system and method of using Virtual Labels in conjunction with an existing software ...
	Bidding for 800 telecommunications traffic The herein disclosed invention stimulates competition between service providers to carry 800 Customers' traffic and facilitates the customer's ability to make economic ...
	Systems and methods for remote access to a display-based bulletin board in a shared user environment The present invention uses a broadband-enabled internet connection to provide an always-on interface to a virtual family, group, or office bulletin board system. Family ...
	Personal authentication system and method thereof This invention is directed to an accurate personal authentication system based on multiple-information provided by a system, in which a bar code reading device, a ...
	Method and system for registering and retrieving data formats for objects using a persistent registry It is an object of the present invention to provide a method and system for registering data formats for a server application. It is another object of the present ...

0.014
Archive: All patents - Links Copyright (c)2006 Eipa-patents.org - All rights reserved