Breaking free from the matrix: Segmentation of fossil images

Abstract

The traditional method for separating a fossil from its matrix is to physically remove the matrix, risking damage to the fossil. Non-destructive technologies, such as computed tomography (CT) scanning, digitally remove the matrix. However, these techniques have multiple disadvantages: they are time consuming, involve highly skilled preparators or technicians, or require expensive equipment. Image segmentation, coupled with wavelet denoising, provides a rapid, inexpensive, and non-destructive way to digitally separate matrix from fossil in standard digital camera images. This method uses off-the-shelf software and produces results that can then be input into software for morphometric analysis or used to speed up more traditional segmentation techniques. A comparison of alternative methods for image segmentation and wavelet denoising indicate that Otsu's method and other global thresholding techniques perform best for this purpose. This approach is illustrated here with images of Eucalyptocrinites holdfasts. The resulting images are used for morphometrics. These methods have great potential for studies that utilize the rapidly growing resource of online museum digital image catalogs.

A radicle solution: morphology and biomechanics of the Eucalyptocrinites ‘root’ system

“…Analyses of the images were performed using ImageJ and the image segmentation techniques described by Honeycutt et al . ().…”