CWP/SU:Seismic Un*xPast, Present, and Future

EAGE Workshop: Open Source Software in E & PVienna, 11 June 2006

John Stockwell, Research Associate

Center for Wave PhenomenaColorado School of Mines

Golden Colorado USAhttp://www.cwp.mines.edu/cwpcodes

Acknowledgment of Support

CWP Consortium Project on Inverse Problems in Complex Structures

Society of Exploration Geophysicists Foundation

Gas Research Institute

Topics

What SU is and is not History of SU Current issues Future plans

Issues

role of SU in geophysics structure of the code human factor ``rules'' of open source

What Seismic Unix is

open source education and research CWP's home environment instant and personal environment

What Seismic Unix is not

not GUI driven not a lot of 3D neither perfect nor complete not a substitute for commercial software ...but fills a role that commercial software

cannot fill

Who uses SU?

academics government researchers small independent contractors researchers in larger companies

Uses of SU

seismic trace manipulation data processing/modeling prototyping/software development quick look at data non-seismic (i.e. GPR radar)

Usage Statistics

approx. 3300+ install messages 2 install messages every 3 days 3-10 downloads per day 524 active listserver members 68 country codes

What makes SU SU?

written in C getpars selfdocs readable source code SEG Y data structure Unix or Unix-like platform

The SEG Y data format

3200 byte EBCDIC reel indentifier 400 byte binary reel header 240 byte binary trace header data in 32 bit IBM tape format Repeat trace header and data

The SU data format

240 byte binary trace header data native binary floats Repeat trace header and data

SY and the origins of SU

SY 1979-1984 Einar Kjartansson (at Stanford)

SY 1984-1986 Shuki Ronen SU 1986 Jack K. Cohen (at CSM) SU 1987 Jack takes SU to Texaco

SU expands

1989-1993 Jack Cohen and Dave Hale 1989-1996 Jack Cohen and John Stockwell 1992 first Internet release of SU 1996-present

Some ``rules'' of open source

stress portability and readability port to many platforms enlist the aid of the users take users needs under consideration know who your users are and how they use

your code

Benefits of open source

clean house new colleagues and partners bug fixes and extensions new codes worldwide presence

Challenges

``no charge''=``no value'' pressure from users grandiose suggestions project expansion some contributed code not open source

Remedies

``open source''=``instant standard'' separate need from want ask for an example keep your project in its scope require references for contributed code

More ``rules''

minimize dependency on 3rd party items avoid relying on ``special features'' give credit to contributors demos should accompany code

submissions stress stability and longevity over novelty

Current and Future issues

SEG Y Rev 1 support 3C 3D cluster update license?

The SEG Y Rev 0 data format

3200 byte EBCDIC reel indentifier 400 byte binary reel header 240 byte binary trace header data in 32 bit IBM tape format ...Repeat trace header and data

Proposed solution, SU Rev 1

512 byte binary header data in big-endian 32 bit ...backward compatability to SU Rev 0 ...with MPI 3D, 3C, and cluster follow

directly

Concluding remarks

SU is here to stay Your help and feedback are welcome Thank you!

Jack K. Cohen, 1939-1996