| DRAFT DICTIONARY CBF/imgCIF Extensions Dictionary | Draft version 1.5 for comment | 
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Definition:
       Type of data-compression method used to compress the array
              data.
Type: ucode
Mandatory item: no
| byte_offset | Using the 'byte_offset' compression scheme as per A. Hammersley and the CBFlib manual, section 3.3.3 | 
| canonical | Using the 'canonical' compression scheme (International Tables for Crystallography Volume G, Section 5.6.3.1) and CBFlib manual section 3.3.1 | 
| none | Data are stored in normal format as defined by _array_structure.encoding_type and _array_structure.byte_order. | 
| packed | Using the 'packed' compression scheme, a CCP4-style packing as per J. P. Abrahams pack_c.c and CBFlib manual, section 3.3.2. | 
| packed_v2 | Using the 'packed' compression scheme, version 2, as per J. P. Abrahams pack_c.c and CBFlib manual, section 3.3.2. | 
Category: array_structure
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