Resource Geology Seismic Routine Library

9 October 1996

*Gather Algebra*	*Data Type Conversion*	*Documentation*
*Equalization and Amplitude Recovery*	*Filtering*	*Data and Geometry Input*
*Header Manipulation*	*Tape Input*	*Migration and Imaging*
*Modeling*	*Pick Handling*	*Plotting*
*Stacking and Semblance Analysis*	*Ascii Manipulation*	*Statics*
*Tomography and Velocity Inversion*	*Gather Muting and Windowing*

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Gather Algebra to manipulate data values

Absval.c	Produce the absolute value of a stream of binary floats.
Ad.c	Shift and add corresponding traces of two gathers.
Add.c	Add two streams of binary floats.
Addc.c	Add a constant to a stream of binary floats.
Clip.c	Clip the extreme values in a stream of binary floats to stated limits.
Copy.c	Enlarge by copying each vector of a stream of binary floats a specified number of times.
Ctr.c	Subtract the average from a stream of binary floats.
Cull.c	Cull from a stream of binary floats any large values.
Demean.c	Subtract from each trace of a stream of binary floats its mean.
Divide.c	Place the quotient of float arguments on the standard output.
Dot.c	Multiply and sum elements of two streams of binary floats.
Double.c	Enlarge by copying each element and each vector of a stream of binary floats.
Fac.c	Multiply a stream of binary floats by a factor.
Frstsub.c	Subtract the first vector of a stream from the next vectors.
Hann.c	Apply a raised cosine Hanning window to a file.
Inv.c	Produce the inverse of a stream of binary floats.
Lim.c	Produce 1 if a value in a stream is within limits, 0 otherwise.
Makenull.c	Generate a stream of binary float zeros.
Modulo.c	Produce the modulo relative to a value, of a stream of floats.
Mult.c	Multiply two streams of binary floats.
Neg.c	Produce the negative of a stream of binary floats.
Nonzero.c	Yield 1 for any value in a stream of binary floats that is not zero, yield zero if it is.
Norm.c	Normalize a stream so the maximum value of vectors will be 1.
Quantile.c	Write the value at the specified quantile of each vector of a stream of binary floats to the standard output.
Reduce.c	Clip the extreme values in a stream of binary floats and then scale them proportionately below the stated limits.
Rev.c	Reverse the order of a stream of binary floats.
Rms.c	Place the rms of a stream of floats on the standard output.
Rndneg.c	Randomly produce the negatives of vectors in a stream of floats.
Sum.c	Sum the vectors of a stream of binary floats, producing one sum vector.
Unit.c	Adjust a stream of POSITIVE floats so each vector sums to 1.
Xinv.c	Produce the inverse of a stream of binary floats, with waterlevel.

Data Type Conversion

8bit.c	Convert a stream of floats to 1-byte integers, with limits.
Ascii2float.c	Convert a stream of whitespace-delimited ASCII to binary float.
Byte2float.c	Convert a stream of 1-byte integers to binary float.
Byte2c2float.c	Convert a stream of 1-byte 2's-complement integers to binary float.
cVAX.c	Convert a stream of VAX floats to IEEE Sun floats.
Int2float.c	Convert a stream of 4-byte integers to binary float.
Short2float.c	Convert a stream of 2-byte integers to binary float.
Short2c2float.c	Convert a stream of 2-byte 2's-complement integers to binary float.

Documentation

Docu.c

Show the comments at the head of a C program.

Equalization and Amplitude Recovery

Agc.c	Automatic gain control on unlabeled traces.
Quanteq.c	Quantile-based trace equalization.
Sphdiv.c	Remove the effect of sherical divergence from a seismic gather.
Tegain.c	Trace equalization on unlabeled traces.

Filtering

Ale.c	Adaptive Line Enhancement prediction error deconvolution.
Dipfil.c	Hale's dip filter for band-limited t-x gathers.
Bpfilter.c	Filter seismograms by ramped bands specified in Hz.
Filter.c	Filter seismograms by ramped spectral windowing.
Rho.c	Apply the Rho filter of Thorson to labeled gathers.
Smooth.c	Smooth a 2-d grid by averaging over a rectangular window.
Videcon.c	Deconvolve seismograms by spectral division and Burg extension.

Data and Survey Geometry Input to calculate location headers

Segy2rg.c	Translate one or more field records in a SEG-Y format file to RG format.
Indexsegy2rg.c	Translate one or more field records in a SEG-Y format file to RG format, rapidly using an index to the file created by segyindex.
Segyindex.c	Create a binary index file to a large multi-record SEG-Y file, for rapid reading by indexsegy2rg.
Segycoords.c	Print source point coordinates in a SEG-Y format file.
Cusptorg	Script to convert CUSP event MEM and GRM files to RG-labeled gathers.
Label.c	Apply headers to a record section, using geometry info.
Map.c	Plot a map from a file of VP coordinates.
Obs.c	Expand the regular parts of observers' reports.

Header Manipulation to handle binary gather and trace labels

Getnt.c	Place the nt of a labeled gather on the standard output.
Getnx.c	Place the nx of a labeled gather on the standard output.
Gett0.c	Place the starttime of a labeled gather on the standard output.
Hd.c	Interprete trace headers supplied in SEG-Y format
Hdappend.c	Append one file of seismograms labeled with headers to another.
Insp.c	Inspect a file of seismograms and their headers.
Merge.c	Merge a file of seismograms with its stripped headers.
Strip.c	Strip headers from a labeled file of seismograms.
Convhd.c	Translate ascii DISCO PRINT output into binary.

Tape Input to handle tapes

Rdrec.c	Read non-equally spaced groups of records from a tape,
Seistape.c	Read seismic gathers from a tape.
Sortrec.c	Produce files of sorted record numbers for seismic data tapes.
Tplook.c	Examine a 1/2-in tape for record lengths and file structure.
Viewtape.sh	Interactively read and plot seismic gathers on tape.
Xtplook.c	Examine a SCSI tape for record lengths and file structure.

Migration and Imaging

Aacmig3d.c	3-D Kirchhoff migration to multiple lines for vertically-variable (only) velocity, with operator anti-aliasing.
Aakmig.c	2-D Kirchhoff migration for arbitrarily variable velocities, with operator anti-aliasing.
Aalatmig.c	3-D Kirchhoff migration for (lat, lon) labeled gathers with vertically-variable (only) velocity, with operator anti-aliasing.
Cmig.c	3-D Kirchhoff migration to single line for vertically-variable (only) velocity.
Cmig3d.c	3-D Kirchhoff migration to multiple lines for vertically-variable (only) velocity.
Cvkmig.c	Kirchhoff migration of unlabeled data at constant velocity.
Dc.c	Downward continuation of zero-offset data.
Fast2d.c	Fast generation of travel times in arbitrary 2-d velocities.
Kmig.c	2-D Kirchhoff migration for arbitrarily variable velocities.
Latmig.c	3-D Kirchhoff migration for (lat, lon) labeled gathers with vertically-variable (only) velocity.
Rtkmig.c	2-D Arbitrary-V Kirchhoff migration for labeled gathers in reduced time.
Stkmig.c	2-D Arbitrary-V Kirchhoff migration for zero-offset gathers.
Stoltmig.c	2-D Stolt F-K migration for zero-offset sections.
Tskmig.c	2-D Arbitrary-V Kirchhoff migration for CIT seismic database.
Xkmig.c	3-D Kirchhoff migration for constant velocity of labeled data.

Modeling for synthetic seismograms

3dmodel4.c	Fourth-order elastic finite-difference modeling, table driven.
Amod.c	Acoustic finite-difference full-wave modeling.
Demult.c	Fast demultiplex or transpose of stream of floats.
Genmodel.c	Generate velocity and density grids from polygons.
Gentool.c	Graphically draw velocity and density polygon models on SunOS 4.x workstations.
Kmod.c	2-D, V(x,z) physical-domain Kirchhoff modeling (inverse migration) for shot gathers.
Netrun.sh	Asynchronous parallel processing using a network of many hosts.
Reflplt.c	Plot the P-to-P reflection coefficient for plane waves at a plane interface between 2 homogeneous, isotropic, elastic half-spaces.
Samodel.c	Acoustic finite-difference modeling with source arrays.
Shiftgen.c	Shift tagged polygons in Genmodel input, for 3-d model slice generation.

Pick Handling to deal with picked time and velocity info

Hdaddsum.c	Add, structure by structure, files of binary ampst amplitude statistic structures labeled with headers.
Offs.c	Routines to interpolate time picks for given CMPs & offsets.
Ordervel.c	Re-order columns of stripped Viewmat (1) picks.
Makemute.c	Create Offs-format t-x picks from stripped, ordered, Viewmat (1) picks of data volumes.
Makevel.c	Create Veloffs-format velocity picks from stripped, ordered, Viewmat (1) picks of CV stacks.
Picks.c	Routines to yield interpolated times for a given offset.
Pickstrip.c	Remove labels from picks made in Viewmat (1).
Veloffs.c	Routines to read and interpolate velocity picks.
Vels.c	Routines to yield interpolated velocities given CMPs and times.
Vmodel.c	Program to yield velocity matrix interpolated from picks.

Plotting of various types of information

Ampplt.c	Plot amplitudes with respect to offset.
Clayplot.c	Make a variable-area-wiggle-trace plot from an unlabeled gather.
Map.c	Plot a map from a file of VP coordinates.
Migplot.c	Plot a labeled migrated section as in Radplot, with depth axis.
Pickplot.c	Plot a seismic gather as in Radplot, with time picks made on it.
Plot.c	Simple plotting routines yielding IGL.
Psigl.c	Convert IGL plot description to PostScript.
Psplot.c	Simple Calcomp-style plotting routines yielding PostScript.
Psun.c	Plots IGL-described plot on workstation.
Radplot.c	Plot a labeled seismic gather according to offset (IGL version).
Radplotps.c	Plot a labeled gather according to offset (PostScript version).
Radrast.c	Quick raster plot of a labeled seismic gather.
Rastsize.c	Find the dimensions of a Clayplot-style rasterfile.
Sunras-ps.c	Convert Sun rasterfiles to PostScript format.
Traceplot.c	PostScript plots of single or multiple wiggle traces using Viewmat (1) style parameters.
Viewmat.c	Variable-density or color viewing and PostScript plotting of matrices and volumes of binary data on a SunOS 4.x workstation.
Xmap.c	View labeled traces relative to geography and well data in X Windows.

Stacking and Semblance Analysis

Array.c	Examine slant stacks of two lines of receivers for directions.
Cmpstack.c	CMP sort, velocity analysis, stack, and AVO analysis.
Dix.c	Simple solution of Dix interval velocities by manual entry.
Extract.c	Find expected amplitude of focused signal (Harlan).
Frstack.c	Calculate gather spectral semblance to thin layer models.
Hist.c	Find standard deviation and amplitude histogram of a stream.
Latcmpstack.c	CMP sort, velocity analysis, stack, and AVO analysis for (lat, lon) labeled gathers.
Nonlin.sh	Remove most linear arrivals of a gather.
Radon.c	Slant stack unlabeled gathers into the intercept time-linear angle domain, or vice-versa.
Rtcmpstack.c	CMP sort, velocity analysis, stack, and AVO analysis for labeled gathers in reduced time.
Slant.c	P-tau transform by slantstack, forward and inverse.
Stack.c	NMO correction, velocity analysis, stack, and AVO analysis.
Sum.c	Sum the vectors of a stream of binary floats, producing one sum vector.
Vsem.c	NMO transform to velocity space, with inverse transform.

Ascii Manipulation to aid shell scripts

Hdmax.c	Place the maximum of a labeled gather on the standard output.
Idiv.c	Place the integer (truncated) quotient of float arguments on the standard output.
Max.c	Place the maximum of a stream of floats on the standard output.
Min.c	Place the minimum of a stream of floats on the standard output.
Plus.c	Place the sum of float arguments on the standard output.
Prod.c	Place the product of float arguments on the standard output.
Rmnl.c	Replace newline characters in a stream with spaces.
Rmnlnsp.c	Remove newline characters from a stream.

Statics for time and amplitude evaluation

Stathist.c	Delay and amplitude static collection and plotting.
Static.c	Pick arrival times automatically to find delays and amplitudes.
Statrm.c	Kluge to remove offset-dependent amplitude static from gather.

Tomography and Velocity Inversion

Conjgrad.sh	Conjugate-gradient iterative slowness back projection example script.
Getalpha.c	Returns conjugate-gradient alpha parameter from command-line inputs.
Getbeta.c	Returns conjugate-gradient beta parameter from command-line inputs.
Gradst.sh	Gradient-step iterative slowness back projection example script.
Hestenes.sh	Hestenes-Stieffel conjugate-gradient iterative slowness back projection example script.
Steep.sh	Steepest-descent iterative slowness back projection example script.
Wideray.sh	Conjugate-gradient iterative slowness back projection with ray error.

Gather Muting and Windowing

Ddwindow.c	Data block copying like UNIX dd (1) with long word parameters.
Flatten.c	Flatten a 3-D binary float volume by stacking or selecting along one of the 3 directions.
Hwindow.c	Copy a window of a labeled 2-dimensional data gather.
Mute.c	Mute a gather of seismic data by interpolating picked mutes.
Shft.c	Shift vectors in a stream of floats, and pad the ends with 0s.
Tile.c	Tile windowed data back into a larger output file.
Window.c	Window or decimate an unlabled 1-, 2-, or 3-d data gather.