Method and apparatus for decimation mode determination utilizing block motion

Abstract

A motion image reproduction apparatus that reproduces motion image data from converted motion image data. The motion image reproduction apparatus includes a block expander that receives converted block data included in the converted motion image data and data indicating a conversion mode in which the converted block data was converted and that expands the converted block data based on the data indicating the conversion mode abd a combiner that produces frame data by combining blocks reproduced via the block expansion performed by the block expander. The block expander reproduces the block by performing the block expansion process in a mode corresponding to at least one of a spatial decimation process in a fixed sampling point position mode, a spatial decimation process in a sampling point position shifting mode, and a temporal decimation process, performed in the production of the converted motion image data. The combiner produces the frame data by combining blocks reproduced via the block expansion process.

1 . A motion image reproduction apparatus that reproduces motion image data from converted motion image data, comprising:
 a block expander that receives converted block data included in the converted motion image data and data indicating a conversion mode in which the converted block data was converted and that expands the converted block data based on the data indicating the conversion mode; and   a combiner that produces frame data by combining blocks reproduced via the block expansion performed by the block expander,   wherein,
 the block expander reproduces the block by performing the block expansion process in a mode corresponding to at least one of a spatial decimation process in a fixed sampling point position mode, a spatial decimation process in a sampling point position shifting mode, and a temporal decimation process, performed in the production of the converted motion image data, and 
 the combiner produces the frame data by combining blocks reproduced via the block expansion process. 
   
     
     
         2 . A motion image reproduction apparatus according to  claim 1 , wherein when the blocks reproduced by the block expander are blocks reproduced from blocks subjected to the spatial decimation process in the sampling point position shifting mode, and the combiner shifts the positions at which the blocks are laid with frame advance. 
     
     
         3 . A motion image reproduction apparatus according to  claim 1 , wherein when the blocks reproduced by the block expander are blocks reproduced from blocks subjected to the spatial decimation process in the sampling point position shifting mode, the combiner shifts the positions at which the blocks are laid with frame advance and performs a pixel value correction process to determine a pixel value in a pixel gap created when blocks were laid or determine a pixel value for an overlapping pixel. 
     
     
         4 . A method of reproducing motion image data from converted motion image data, comprising the steps of:
 expanding a block by receiving converted block data included in the converted motion image data and data indicating a conversion mode in which the converted block data was converted, and expanding the converted block data based on the data indicating the conversion mode; and   combining blocks reproduced in the block expansion step to produce frame data,   wherein,
 the block expansion step reproduces the block by performing the block expansion process in a mode corresponding to at least one of a spatial decimation process in a fixed sampling point position mode, a spatial decimation process in a sampling point position shifting mode, and a temporal decimation process, performed in the production of the converted motion image data, and 
 the block combining step produces the frame data by combining blocks reproduced via the block expansion process. 
   
     
     
         5 . A method of reproducing motion image data, according to  claim 4 , wherein in the block combining step, when the blocks reproduced by the block expander are blocks reproduced from blocks subjected to the spatial decimation process in the sampling point position shifting mode, the positions at which to lay the blocks are shifted with frame advance. 
     
     
         6 . A method of reproducing motion image data, according to  claim 4 , wherein the block combining step includes the step of, when the blocks reproduced by the block expander are blocks reproduced from blocks subjected to the spatial decimation process in the sampling point position shifting mode, shifting the positions at which the blocks are laid with frame advance and performing a pixel value correction process to determine a pixel value in a pixel gap created when blocks were laid or determine a pixel value for an overlapping pixel. 
     
     
         7 . A computer program for executing a process of reproducing motion image data from converted motion image data, the process comprising the steps of:
 expanding a block by receiving converted block data included in the converted motion image data and data indicating a conversion mode in which the converted block data was converted, and expanding the converted block data based on the data indicating the conversion mode; and   combining blocks reproduced in the block expansion step to produce frame data,   wherein,
 the block expansion step reproduces the block by performing the block expansion process in a mode corresponding to at least one of a spatial decimation process in a fixed sampling point position mode, a spatial decimation process in a sampling point position shifting mode, and a temporal decimation process, performed in the production of the converted motion image data, and 
 the block combining step produces the frame data by combining blocks reproduced via the block expansion process.