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File Formats

...under construction...

CCP4, MRC, and variants


 byte\       word\       word\       field       type      description                    [CCP4](http://www.ccp4.ac.uk/html/maplib.html#description)   [MRC](http://www2.mrc-lmb.cam.ac.uk/research/locally-developed-software/image-processing-software/#image)   [MRC-IMOD](http://bio3d.colorado.edu/imod/doc/mrc_format.txt)
offset     offset\      index\                                                                                                                                                                                                                                     
         (first=0)   (first=1)

     0           0           1       N ~x~       int32     3-D size of data array,\                                                                                                                                                                                
                                                           fastest changing first

     4           1           2       N ~y~       int32

     8           2           3       N ~z~       int32

    12           3           4       mode        int32     data type:\                    additionally:\                                                                                                                                                           additionally:
                                                           0: signed 8-bit integer\       5: same as mode 0                                                                                                                                                        6: 16-bit unsigned integer
                                                           1: signed 16-bit integer\                                                                                                                                                                               16: 3x8-bit unsigned int, RGB
                                                           2: 32-bit float\                                                                                                                                                                                        NOTE: mode 0 may be signed
                                                           3: 16-bit complex integer\                                                                                                                                                                              or unsigned depending
                                                           4: 32-bit complex float                                                                                                                                                                                 on codes found at byte
                                                                                                                                                                                                                                                                   offset 152 and 156

    16           4           5     Start ~x~     int32     number of the first element\                                                                                                                                                                            
                                                           in each dimension, if this\                                                                                                                                                                             
                                                           is a sub-array of another

    20           5           6     Start ~y~     int32

    24           6           7     Start ~z~     int32

    28           7           8   Intervals ~x~   int32     number of grid intervals\                                                                                                                                                                               
                                                           along each dimension

    32           8           9   Intervals ~y~   int32

    36           9          10   Intervals ~z~   int32

    40          10          11  Cell Length ~x~  float32   cell length in angstrom

    44          11          12  Cell Length ~y~  float32

    48          12          13  Cell Length ~z~  float32

    52          13          14   Cell Angle α    float32   cell angles in degrees         \2/3.                                                       ignored by IMOD

    56          14          15   Cell Angle β    float32

    60          15          16   Cell Angle γ    float32

    64          16          17    Column axis    int32     1 -> X\                                                                                                                                                                                                
                                                           2 -> Y\                                                                                                                                                                                                
                                                           3 -> Z

    68          17          18     Row axis      int32

    72          18          19   Section axis    int32

    76          19          20  Minimum density  float32   statistics calculated\                                                                                                                                                                                  
                                                           from the data

    80          20          21  Maximum density  float32

    84          21          22   Mean density    float32

...under construction...