DDS supports the Colorado School of Mines (Sesimic Un*x) format as "su". It is basically a modified segy format without a Line Header (see segy). The effective default attributes for segy output is:

format= su float 4 ibm ebcdic no_green_prefix no_green_suffix

Examples of attributes available for su (see Attributes) include the following:

Attributes            Description
---------------       ---------------------------------
no_green_prefix       no green word prefix
no_green_suffix       no green word suffix
green_prefix 4|8      green word prefix size
green_suffix 4|8      green word suffix size
integer 1|2|4|8       integer samples size
float 4|8 ibm|ieee[x] float samples type & size
hdrswap               binary and trace headers "Little Endian"
ascii                 card header text is ascii format
ebcdic                card header text is ebcdic format
charisma              charisma format
TrcNumSmp             handle variable trace lengths

Other effective segy defaults include:

axis= t x y
sort.x=CdpTrcNum
sort.y=FieldRecNum

DDS automatically detects the su format and attributes of input binary data. If they conflict with attributes explicitly defined by format, a warning is issued and the override is honored. Output data attributes take predefined defaults, unless explicitly overridden.

The su seismic format does not contain any PREAMBLE Line Header informat and is described only by the Trace structure, SEGY_TRACE (SEQUENCE) from the segy "${DDSROOT}/src/lib/dds3/segy.fmt.dds" Dictionary. "${DDSROOT}/src/lib/dds3/segy.map.dds" provides default mapping Definitions ("map:*:su.field" are the same as for segy).