Encoding method, decoding method, encoding device and decoding device

Abstract

Disclosed is an encoding method including a transform step (S110a) for transforming an input signal; a quantization step (S120) for quantizing the transform output signal; and an entropy encoding step (S130) for entropy encoding quantized coefficients. The transform step (S110a) includes a first transform step (S112) for generating the first transform output signal by way of performing a first transform on the input signal using a first transform coefficient; and a second transform step (S116a) for generating a second transform output signal by way of performing a second transform using a second transform coefficient on a first partial signal which is a portion of the first transform output signal, and outputting a transform output signal which includes the generated second transform output signal and a second partial signal which is the portion of the first transform output signal excluding the first partial signal. In the second transform step (S116a), either the range of the first transform output signal for the second transform as the first partial signal, and / or the second transform coefficient, is temporally or spatially adaptively determined.

Description

technical field [0001] The present invention relates to an encoding method for encoding audio, still images, and moving images, and more particularly, to an encoding method including transform processing for transforming an input signal from a time-space domain to a frequency domain. Background technique [0002] In order to compress audio data and video data, many audio coding standards and video coding standards have been developed. Examples of video encoding standards include the ITU-T standard called H.26x and the ISO / IEC standard called MPEG-x. The latest video encoding standard is a standard called H.264 / MPEG-4AVC. [0003] figure 1 It is a block diagram showing the configuration of a conventional encoding device 1600 . Such as figure 1 As shown, the encoding device 1600 includes a transform unit 1610, a quantization unit 1620, and an entropy encoding unit 1630, and encodes audio data and video data at a low bit rate. [0004] The conversion unit 1610 generates a ...

AI Technical Summary

Problems solved by technology

[0024] As described above, in the transformation using a transformation matrix composed of transformation coefficients calculated based on the statistical properties of the input signal such as KLT, there is a problem that the amount of calculation is large and the data volume of the transformation coefficients is large. Therefore, in the conventional Difficulty using KLT when coding

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