Compressing and decompressing image data using compacted region transforms

A method of compressing one or more input data items as compressed data, the method comprising:

• obtaining a set of one or more reference data items and a set of transforms identified from the one or more input data items;
• and
• generating compressed data encoding each of the one or more input data items as a representation of a selective application of one or more transforms from the identified set of transforms to one of the identified set of one or more reference data items.

A non-transitory computer readable storage medium having stored thereon a computer readable dataset description of an integrated circuit that, when processed in an integrated circuit manufacturing system, causes the integrated circuit manufacturing system to manufacture a data compressor configured to compress one or more input data items as compressed data, the compressor being configured to:

• obtain a set of one or more reference data items and a set of transforms identified from the one or more input data items;
• and
• generate compressed data encoding each of the one or more input data items as a representation of a selective application of one or more transforms from the identified set of transforms to one of the identified set of one or more reference data items.