Network television platform moving pictures experts group (MPEG) audio multi-phase synthesis filtering method

Abstract

The invention relates to a network television platform moving pictures experts group (MPEG) audio multi-phase synthesis filtering method, which is used for converting frequency domain signals of network television platform MPEG audio into time domain signals for output. The method comprises the step of: performing discrete cosine transform on N floating points of an input sequence of the MPEG audio to obtain 2N values of an output sequence, wherein the step further comprises the following steps of: 1) acquiring discrete cosine transform (DCT)-II values of the N points; 2) obtaining DCT values of the N points by utilizing the periodicity and symmetry of a cosine function; and 3) outputting the DCT values of the N points as the 2N values of the output sequence. By the network television platform MPEG audio multi-phase synthesis filtering method, the frequency domain signals can be rapidly converted into the time domain signals for output; and compared with the conventional method, the invention has the advantages that: floating point multiplication operations are reduced, the decoding efficiency is high and the execution efficiency of an MPEG technology is remarkably improved.

Description

technical field [0001] The invention relates to the field of embedded platform network TV and set-top box, more specifically, relates to a network TV platform MPEG audio polyphase synthesis filtering method. Background technique [0002] In multimedia IT products such as Internet TV, MP3 player or set-top box, audio and video codec technology is the soul of these products. Good audio and video codec technology can bring consumers a more perfect audio-visual experience at the smallest cost . Among them, the MPEG (Moving Pictures Experts Group, Moving Pictures Experts Group) technology in the audio field is a codec technology widely used at present. The last step of MPEG audio decoding is polyphase synthesis filtering, the purpose of which is to convert the frequency domain signal into a time domain signal output. This step requires a large number of floating-point multiplication operations, including the step of performing discrete cosine transform on N floating-point numbe...

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is to provide a network TV platform MPEG audio polyphase synthesis filter method for the above-mentioned high number of calculations and low decoding efficiency of the existing polyphase synthesis filter method

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