Gradient-based value mapping for colorization of two-dimensional fields

Arvind Visvanathan, Stephen E. Reichenbach, Qingping Tao

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Scopus citations


This paper develops a method for automatic colorization of two-dimensional fields presented as images, in order to visualize local changes in values. In many applications, local changes in values are as important as magnitudes of values. For example, in topography, both elevation and slope often must be considered. Gradient-based value mapping for colorization is a technique to visualize both value (e.g., intensity or elevation) and gradient (e.g., local differences or slope). The method maps pixel values to a color scale in a manner that emphasizes gradients in the image. The value mapping function is monotonically non-decreasing, to maintain ordinal relationships of values on the color scale. The color scale can be a grayscale or pseudocolor scale. The first step of the method is to compute the gradient at each pixel. Then, the pixels (with computed gradients) are sorted by value. The value mapping function is the inverse of the relative cumulative gradient magnitude function computed from the sorted array. The value mapping method is demonstrated with data from comprehensive two-dimensional gas chromatography (GC×GC), using both grayscale and a pseudocolor scale to visualize local changes related to both small and large peaks in the GC×GC data.

Original languageEnglish (US)
Title of host publicationVisual Information Processing XV
StatePublished - 2006
EventVisual Information Processing XV - Kissimmee, FL, United States
Duration: Apr 18 2006Apr 19 2006

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
ISSN (Print)0277-786X


ConferenceVisual Information Processing XV
Country/TerritoryUnited States
CityKissimmee, FL


  • Color mapping
  • Colorization
  • Comprehensive two-dimensional gas chromatography (GC×GC)
  • Digital image processing
  • Gradient
  • Image enhancement
  • Pseudocolor
  • Visualization

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Gradient-based value mapping for colorization of two-dimensional fields'. Together they form a unique fingerprint.

Cite this