Automatic digitization of pluviograph strip charts

An algorithm for automatic digitization of pluviograph strip charts is presented. The rainfall signal is incrementally extracted from the scanned image of a strip chart by combining the moving average method and the curve edge following method. The mechanical properties of float-based rain gauge were used as constraints in the algorithm design. The algorithm was tested on 58 strip chart images. The comparison between the data derived from the algorithm and the data from the Slovenian Environment Agency shows that the algorithm produces an accurate rainfall time series except for the charts that contain ink smudges. Thus, the algorithm is well suited as a main component of an interactive system that would enable visual inspection of the detected rainfall curve and its possible adjustment.

[1]  J. Hay,et al.  High-resolution studies of rainfall on Norfolk Island: Part II: Interpolation of rainfall data , 1998 .

[2]  P. E. O'Connell,et al.  Stochastic point process modelling of rainfall. I. Single-site fitting and validation , 1996 .

[3]  Neil R. McIntyre,et al.  Performance of ten rainfall-runoff models applied to an arid catchment in Oman , 2009, Environ. Model. Softw..

[4]  Thomas H. Cormen,et al.  Introduction to algorithms [2nd ed.] , 2001 .

[5]  A Point Rainfall Generator With Internal Storm Structure , 1986 .

[6]  Wayne C. Huber,et al.  Hydrology and Floodplain Analysis , 1989 .

[7]  Efrat Morin,et al.  Rainfall―runoff modeling in a small hyper-arid catchment , 2009 .

[8]  Giorgio Querzoli,et al.  An automatic system for rainfall signal recognition from tipping bucket gage strip charts , 2007 .

[9]  Bernd Jähne,et al.  BOOK REVIEW: Digital Image Processing, 5th revised and extended edition , 2002 .

[10]  Jean Ponce,et al.  Computer Vision: A Modern Approach , 2002 .

[11]  Mohd Yusoff Mashor,et al.  Seeded Region Growing Features Extraction Algorithm; Its Potential Use in Improving Screening for Cervical Cancer , 2005 .

[12]  Wolfgang Schilling,et al.  Rainfall data for urban hydrology: what do we need? , 1991 .

[13]  Andrew Metcalfe,et al.  Stochastic point process modelling of rainfall. II. Regionalisation and disaggregation , 1996 .

[14]  Christian Onof,et al.  Rainfall disaggregation using adjusting procedures on a Poisson cluster model , 2001 .

[15]  Igor Kononenko,et al.  Machine Learning and Data Mining: Introduction to Principles and Algorithms , 2007 .

[16]  Dan Gusfield Algorithms on Strings, Trees, and Sequences - Computer Science and Computational Biology , 1997 .

[17]  Mark S. Nixon,et al.  Feature Extraction and Image Processing , 2002 .

[18]  Giorgio Boni,et al.  Extreme rainfall events: Learning from raingauge time series , 2006 .

[19]  Emanuele Trucco,et al.  Introductory techniques for 3-D computer vision , 1998 .

[20]  David A. Woolhiser,et al.  A Stochastic Model of Dimensionless Thunderstorm Rainfall , 1985 .

[21]  Ronald L. Rivest,et al.  Introduction to Algorithms , 1990 .

[22]  M. Kubo,et al.  Estimation of the density of the snowfall particle using electric balances and 2DVD , 2011, SICE Annual Conference 2011.