US 2004/0175049 A1Published application

Moving image coding method and apparatus

AssigneeMatsushita Electric Industrial Co., Ltd.

InventorsTakahiro Yamamoto, Mitsuya Nakahara, Kazuyuki Inokuma, Shinji Kitamura

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Abstract

A memory controller controls so that the number of maximum macro blocks for which inter coding is performed in one image frame is set to a smaller value than the number of macro blocks configuring the image frame, the capacity of the reference image memory is reduced to capacity for the maximum macro blocks for which inter coding is performed, macro block positions for which intra coding and inter coding are performed in the next frame are determined based upon image information and the quantity of codes in the coding of a present image and reference image macro blocks equivalent to only macro block positions for which inter coding is determined to be performed in the next frame are stored in the reference image memory.

Claims43

Dependent claims

A moving image coding method for coding a moving image, every macro block which forms a predetermined area of a present image, with using intra coding in which image data are orthogonal-transformed, and then image data after the orthogonal-transformation are quantized and variable-length coded, and inter coding in which a motion vector of the present image relative to a reference image is detected, motion compensation for the reference image with using the motion vector is performed, differential data between the present image and the reference image after the motion compensation are orthogonal-transformed, and then differential data after the orthogonal transformation are quantized and variable-length coded, and

for storing, for purpose of the inter coding, a reference image of image frame next to the present image generated by inverse-quantizing and inverse-orthogonal-transforming image data after the quantization or differential data after the quantization in a reference image memory, comprising the step of:
determining position of a macro block which is intra-coded or inter-coded, in a range of the maximum number of macro blocks inter-coded in one image frame, when an image (Mth frame, M≦N−1) prior to a present image (Nth frame) is coded.

A moving image coding apparatus provided with encoding means for encoding a moving image, every macro block which forms a predetermined area of a present image, with using intra coding for in which image data are orthogonal-transformed, and then image data after the orthogonal transformation are quantized and variable-length coded, and inter coding in which a motion vector of the present image relative to a reference image is detected, motion compensation for the reference image with using the motion vector is performed, differential data between the present image and the reference image after the motion compensation are orthogonal-transformed, and then differential data after the orthogonal transformation are quantized and variable-length coded, and

a reference image memory for storing, for purpose of the inter coding, a reference image of image frame next to the present image generated by inverse-quantizing and inverse-orthogonal-transforming image data after the quantization or differential data after the quantization, comprising:
determining means for determining position of a macro block which is intra-coded or inter-coded in a range of the maximum number of macro blocks which is inter-coded in one image frame when an image (Mth frame, M≦N−1) prior to a present image (Nth frame) is coded.

Dependencies are inferred from the claim text.

Facts

Application: 10/644,854Filed 21 Aug 2003
Priority: JP P2003-0571994 Mar 2003
Published: 9 Sep 2004
Term ends: Not estimatedThe source records don’t support an estimate.

Classification6 codes

H04N 19/426
Characterised by memory arrangements: using memory downsizing methods
H04N 19/142
Characterised by the element, parameter or criterion affecting or controlling the adaptive coding: detection of scene cut or scene change
H04N 19/152
Data rate or code amount at the encoder output: by measuring the fullness of the transmission buffer
H04N 19/164
Characterised by the element, parameter or criterion affecting or controlling the adaptive coding: feedback from the receiver or from the…