DDS supports the BPAmoco USP (Un*x Seismic Procssing) format as "usp". The effective default attributes for usp output is:

format= usp float 4 ieee green_prefix 4

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

Attributes        Description
---------------   -------------------------------------------
green_prefix 4    4-byte green word prefix
no_green_suffix   no green word suffix
float 4 ieee      4-byte ieee float samples
dense.2           2nd axis is padded (3rd axis may be sparse)
hlh_cube          use previously stored DDS axis information
ignore_hlh        ignore hlh entirely

Other effective usp defaults include:

axis= t x y
sort.x=TrcNum
sort.y=RecNum

DDS automatically detects the usp 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. Output is forced to include green word prefix and ascii characters.

The usp seismic format is described by two major types, USP_LINE (PREAMBLE) and USP_TRACE (SEQUENCE). This format is created using the "${DDSROOT}/usp.fmt.dds" Dictionary and "${DDSROOT}/usp.map.dds" provides the default mapping Definitions. Either of these can be copied into some other directory and edited to modify the format. Point DDS to this directory with DDS_PATH.