RGPR: a free and open-source software package to process and visualise ground-penetrating radar (GPR) data

RGPR is a free and open-source software package to read, export, analyse, process and visualise ground-penetrating radar (GPR) data. RGPR is written in R, a high-level programming language for statistical computing and graphics that is freely available under the GNU General Public License and runs on Linux, Windows and MacOS.

Note

• supported binary formats:

  • Sensors & Software file format (.DT1, .HD)
  • MALA file format (.rd3, .rad)
  • SEG-Y file format (.sgy) from RadSys Zond GPR device

  Do you miss your preferred file format? Send me the file format description with a test file and I will adapt the RGPR-package to support this file format.

• RGPR only support reflection data such as surface-based GPR data (no support for cross-borehole GPR data)

• the documentation is still incomplete (but check the tutorials, http://emanuelhuber.github.io/RGPR)

This is an ongoing project. If you have any questions, don't hesitate to contact me:

emanuel.huber@alumni.ethz.ch

Thank you!

Online tutorials

Check the companion website for more info, tutorials, etc.

http://emanuelhuber.github.io/RGPR

How to install/load

if(!require("devtools")) install.packages("devtools")
devtools::install_github("emanuelhuber/RGPR")
library(RGPR)

frenkeLine00  # data from the package

plot(frenkeLine00)

Existing functions

Reading/writing/export functions

• readGPR(), formats: Sensors & Software (.d11, .hd), MALA (.rd3, .rad), SEG-Y for RadSys Zond GPR device (.sgy), R (rds)
• writeGPR(): format DT1 (Sensors&Software), rds (R-format), ASCII, 'xyz'
• exportPDF(): high quality pdf graphic
• exportDelineations()
• exportFID(): ASCII-file
• exportCoord(): SpatialLines, SpatialPoints or ASCII-file
• exportProc(): ASCII-file

Plot functions

• plot():
  • type = "raster"
  • type = "wiggles"
• lines()
• plot3D()

GPR data editing and referencing

• Trace position reversal: reverse()
• Vertical trace shift: traceShift()
• Georeference coordinates (based on center and rotation angle): georef()
• Interpolate trace position (x, y, z) from known positions: interpPos()
• Estimate shift between two parallel profiles: shiftEst()

GPR data analysis and transforms

• Trace amplitude: ampl(), plot trace amplitude: plotAmpl()
• Average trace: traceAverage()
• Spectrum (f-x and f-k): spec(x, type = c("f-x", "f-k"))
• Structure tensor: strTensor(), plot structure tensor: plotTensor()

GPR data interpolation

• Trace interpolation at regularly spaced positions: regInterpPos()
• Upsampling (time and position): upsample()
• Relative position on the radargramm: relPos()

GPR signal correction

• DC-shift correction: dcshift()
• Low-frequency ('wow') component removal: dewow() (type = "MAD", "Gaussian")
• First-break picking: firstBreak() (method = "coppens", "threshold", "MER")
• Shift the traces vertically such that they start at time zero: time0Cor()
• Constant offset time correction: timeCorOffset()

GPR signal attenuation compensation (gain)

• Linear, power, exponential, ang agc gain: gain() (type = "power", "exp", "agc")

GPR signal enhancement

• Clip the GPR signal values: clip()
• Gamma correction of the GPR signal values: gammaCorrection()
• Trace scaling: traceScaling()
• Trace filters (1D): filter1D(): type = "median", "hampel", "Gaussian"
• Radargramm filters (2D): filter2D(): type = "median3x3", "adimpro"
• Trace frequency filter (1D): fFilter(): freqency filter, type = 'low','high','bandpass'
• Frequency-wavenumber filter (2D): fkFilter()
• Trace (1D) and radargramm (2D) convolution: conv1D() and conv2D()
• Deconvolution: deconv() (type = "spiking", "wavelet", "min-phase", "mixed-phase")
• Phase rotation rotatePhase()

GPR signal velocity

• Common-mid point analysis (CMP): CMPAnalysis() (method = "semblance", "winsemblance", "wincoherence")
• Normal Move-Out correction (NMO): NMOCor()

GPR data topographic correction and migration

• Topography correction and topographic Kirchhoff migration: migration() (type = "static", "kirchhoff")

GPR structure delineation and mapping [EH]

• delineate()
• rmDelineations()<-
• delineations()
• addDelineation()
• plotDelineations3D()
• plotDelineations()
• identifyDelineation()

Processing

• Apply many processing steps: papply()

Miscellaneous

• Operators: +, -, *, /, ^
• Mathematical functions: max(), min(), mean(), median(), summary(), range(), abs(), sign(), sqrt(), ceiling(), ...
• Matrix functions: length(), nrow(), ncol(), dim()
• Coercion: as.matrix(), as.numeric(), as.double(), as.list(), as.SpatialLines(), as.SpatialPoints()

Setter/getter functions

• depthunit() & depthunit()<-
• description() & description()<-
• ann() & ann()<-
• coord() & coord()<-
• crs() & crs()<-
• fid() & fid()<-
• filepath() & filepath()<-
• pos() & pos()<-
• posunit() & posunit()<-
• proc<-() & processing
• name() & name()<-
• values() & values()<-
• vel() & vel()<-
• gethd()
• svDate() & svDate()<-

List of the functions from the class GPR

library(RGPR)
mtext <-  showMethods(class="GPR", printTo =FALSE )
i <- grepl('Function', mtext) & grepl('package RGPR', mtext) 
fvec <- gsub( "Function(\\:\\s|\\s\\\")(.+)(\\s\\(|\\\")(.+$)", "\\2", mtext[i] )
fvec

List of the functions from the class GPRsurvey

library(RGPR)
mtext <-  showMethods(class="GPRsurvey", printTo =FALSE )
i <- grepl('Function', mtext) & grepl('package RGPR', mtext) 
gvec <- gsub( "Function(\\:\\s|\\s\\\")(.+)(\\s\\(|\\\")(.+$)", "\\2", mtext[i] )
gvec

Incomplete overview of the RGPR-package

?RGPR

Contributions

Thanks to:

• @jmerc13