MPEG system which decompresses and then recompresses MPEG video data before storing said recompressed MPEG video data into memory

In a system for processing image representative digital data, an MPEG compatible decoder comprising:

• an input network for receiving a data stream of compressed image representative data;
• a decompressor for decompressing compressed data from said input network;
• a motion information processing network for processing decompressed data from said decompressor;
• a memory unit for storing data processed by said motion processing network;
• an output image processor for processing data stored by said memory unit;
• and
• a compressor for compressing data processed by said motion processing network before being stored by said memory unit;
• wherein said compressor comprises
• a block based first compressor exhibiting a variable data compression characteristic;
• a block based second compressor exhibiting a fixed data compression characteristic, said second compressor operating in parallel with said first compressor;
• means for applying blocks of image data to both said first and second compressors concurrently;
• means coupled to said first compressor for determining if a data block processed by said first compressor exhibits a desired compression factor;
• and
• a selection network for selectively conveying to said memory unit (a) variable compressed data from said first compressor when said variable compressed data exhibits a desired predetermined compression factor or greater, and (b) fixed compressed data from said second compressor when said variable compressed data exhibits less than said compression factor.

In a system for processing image representative digital data, an MPEG compatible decoder comprising:

• an decoder for decoding a received datastream of compressed image representative data;
• a decompressor for decompressing compressed data from said decoder;
• a memory unit with an input and an output;
• a block compressor for providing compressed data to said input of said memory unit;
• a block decompressor for decompressing data provided from said output of said memory unit;
• a motion information processor for processing decompressed data from said block decompressor;
• a combiner for combining output signals from said decompressor and from said motion processor to produce data for application to said compressor;
• and
• an output image processor for processing data stored by said memory unit.

A method for processing encoded MPEG compatible image representative digital input data comprising the steps of:

• (a) decoding said input data to produce decoded data;
• (b) decompressing said decoded data to produce decompressed data;
• (c) compressing information including said decompressed data to produce compressed information;
• (d) storing said compressed information in memory;
• (e) decompressing information stored in said memory to produce decompressed stored information;
• (f) motion processing said decompressed stored information to produce motion information;
• and
• (g) combining said motion information with said decompressed data to produce said information compressed in said compressing step (c).

In a system for processing input image representative information, an MPEG compatible decoder comprising:

• a decompressor for decompressing an input datastream containing MPEG coded data to produce decompressed data;
• a compressor for compressing said decompressed data to produce recompressed data;
• a memory for storing said recompressed data;
• an output network for processing data stored by said memory;
• and
• a motion information processing network coupled to said memory and to said compressor for processing image motion information associated with said input image representative information.

A method of processing a digital datastream of MPEG coded image representative data comprising the steps of;

• (a) decompressing said input datastream of MPEG coded data or produce decompressed data;
• (b) compressing said decompressed data to produce recompressed data;
• (c) storing said recompressed data;
• (d) providing said stored recompressed data to an image information processing network;
• and
• (e) Processing image motion information in association with said compressing step and said storing step.