Single UF Ray Structure

The data is in a single file for a complete volume scan. The file includes a series of stand-alone rays (data acquired for a given pointing direction). Header information is duplicated for each ray.

Within a ray, data is organized as 16-bit words, byte swapped in the big endian convention. The exception is that each ray starts and ends with a 32-bit record size indicating the number of bytes in the ray.

ASCII text is usually left justified, space padded but some converter programs produce null terminated text.

The data format supports breaking large rays into several records. In this case, the multiple records within the ray have identical formats, with different field headers and data fields. The IRIS converter programs do not support this feature, and always place a ray in a single record. The optional header is placed in the ray for the first ray of a file.

The structure names usually end with a 2 to indicate that they are 2-byte aligned. By default, all IRIS structures are 4-byte aligned unless they end in a 2 or 8.

ray size 4 Bytes

<uf_mandatory_header2> 45 Words

<uf_optional_header> 0 or 12 Words

<uf_data_header2> 3 + 2N Words

<uf_field_header2> #1 19 or 21 or 25 Words

data from field #1 M Words

<uf_field_header2> #2 19 or 21 or 25 Words

data from field #2 M Words

...(repeats for each data type)...

ray size 4 Bytes

For more information, see the uf.h header file.