Image processing, compressing, decompressing, transmitting, sending and receiving devices and methods, programs thereof and displaying device

An image processing device comprising a plurality of first image processors for compressing data capacity of input image data of a raster image to output compressed data of the raster image, a memory for storing the compressed data, and a plurality of second image processors for decompressing compressed data read out of the memory to output decompressed output image data,

• at least one of the first image processors including:
• a reversible coder for dividing the input image data into a plurality of areas including a plurality of pixels and representing the input image data by representative value data as a gradation component of a common part of the pixels within each area and difference data as a difference between input gradation data of each pixel and the representative value data to execute a data conversion;
• and
• a bit plane compressor for executing a multi-valued dither processing of the difference data on the basis of a two-dimensional dither matrix to reduce a bit plane number of the difference data to obtain compressed difference data,
• at least one of the second image processors including:
• a bit plane decompressor for executing a bit addition processing of the compressed difference data read out of the memory on the basis of the two-dimensional dither matrix to obtain output difference data;
• and
• a reversible decoder for adding the representative value data to the output difference data to execute a data conversion to output image data,
• the compressed data including the representative value data and the compressed difference data,
• the image processing device further comprising:
• a compression method change controller for determining a compression rate in the reversible coder and a compression rate in the bit plane compressor on the basis of the input image data;
• a first selector for selecting the compressed data of one first image processor, determined by the compression method change controller, including the reversible coder executing the data compression at the determined compression rate and the bit plane compressor executing the data compression at the determined compression rate, to output the selected compressed data;
• first means for storing the compressed data selected by the first selector into the memory;
• second means for storing a flag signal as an output signal of the compression method change controller into the memory;
• and
• a second selector for selecting the output image data of one second image processor selected on the basis of the flag signal read out of the memory to output the selected output image data.

An image transmitting device comprising a first processing unit including a first image processor for compressing data capacity of input image data of a raster image to transmit compressed data of the raster image from the first processing unit and a second processing unit including a second image processor for decompressing transmitted compressed data to output decompressed output image data,

• the first image processor including:
• a reversible coder for dividing the input image data into a plurality of areas including a plurality of pixels and representing the input image data by representative value data as a gradation component of a common part of the pixels within each area and difference data as a difference between input gradation data of each pixel and the representative value data to execute a data conversion;
• and
• a bit plane compressor for executing a multi-valued dither processing of the difference data on the basis of a two-dimensional dither matrix to reduce a bit plane number of the difference data to obtain compressed difference data,
• the second image processor including:
• a bit plane decompressor for executing a bit addition processing of the compressed difference data of the compressed data transmitted from the first processing unit on the basis of the two-dimensional dither matrix to obtain output difference data;
• and
• a reversible decoder for adding the representative value data to the output difference data to execute a data conversion to output image data,
• the compressed data including the representative value data and the compressed difference data.

A displaying device comprising a first image processor for compressing data capacity of input image data of a raster image to output compressed data of the raster image, a memory for storing the compressed data, a second image processor for decompressing compressed data read out of the memory to output decompressed output image data, and a display for displaying an image according to the image data produced by the second image processor,

• the first image processor including:
• a reversible coder for dividing the input image data into a plurality of areas including a plurality of pixels and representing the input image data by representative value data as a gradation component of a common part of the pixels within each area and difference data as a difference between input gradation data of each pixel and the representative value data to execute a data conversion;
• and
• a bit plane compressor for executing a multi-valued dither processing of the difference data on the basis of a two-dimensional dither matrix to reduce a bit plane number of the difference data to obtain compressed difference data,
• the second image processor including:
• a bit plane decompressor for executing a bit addition processing of the compressed difference data read out of the memory on the basis of the two-dimensional dither matrix to obtain output difference data;
• and
• a reversible decoder for adding the representative value data to the output difference data to execute a data conversion to output image data,
• the compressed data including the representative value data and the compressed difference data.

An image processing method comprising a first image processing step for compressing data capacity of input image data of a raster image to output compressed data of the raster image, a storing step for storing the compressed data into a memory, and a second image processing step for decompressing compressed data read out of the memory to output decompressed output image data,

• the first image processing step for data compression including:
• a reversible coding process for dividing the input image data into a plurality of areas including a plurality of pixels and representing the input image data by representative value data as a gradation component of a common part of the pixels within each area and difference data as a difference between input gradation data of each pixel and the representative value data to execute a data conversion;
• and
• a bit plane compressing process for executing a multi-valued dither processing of the difference data on the basis of a two-dimensional dither matrix to reduce a bit plane number of the difference data to obtain compressed difference data,
• the second image processing step for data decompression including:
• a bit plane decompressing process for executing a bit addition processing of the compressed difference data read out of the memory on the basis of the two-dimensional dither matrix to obtain output difference data;
• and
• a reversible decoding process for adding the representative value data to the output difference data to execute a data conversion to output image data,
• the compressed data including the representative value data and the compressed difference data.

An image transmitting method comprising a first image processing step for compressing data capacity of input image data of a raster image, a transmitting step for transmitting compressed data of the raster image from a first processing unit to a second processing unit and a second image processing step for decompressing transmitted compressed data to output decompressed output image data,

• the first image processing step for data compression including:
• a reversible coding process for dividing the input image data into a plurality of areas including a plurality of pixels and representing the input image data by representative value data as a gradation component of a common part of the pixels within each area and difference data as a difference between input gradation data of each pixel and the representative value data to execute a data conversion;
• and
• a bit plane compressing process for executing a multi-valued dither processing of the difference data on the basis of a two-dimensional dither matrix to reduce a bit plane number of the difference data to obtain compressed difference data,
• the second image processing step for data decompression including:
• a bit plane decompressing process for executing a bit addition processing of the compressed difference data of the compressed data transmitted from the first processing unit on the basis of the two-dimensional dither matrix to obtain output difference data;
• and
• a reversible decoding process for adding the representative value data to the output difference data to execute a data conversion to output image data,
• the compressed data including the representative value data and the compressed difference data.