Research output: Contribution to journal › Article › peer-review
Classification of protein crystallisation images using Fourier descriptors. / Walker, Christopher G.; Foadi, James; Wilson, Julie.
In: Journal of Applied Crystallography, Vol. 40, No. 3, 06.2007, p. 418-426.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Classification of protein crystallisation images using Fourier descriptors.
AU - Walker, Christopher G.
AU - Foadi, James
AU - Wilson, Julie
PY - 2007/6
Y1 - 2007/6
N2 - The two-dimensional Fourier Transform (2D-FT) is well suited to the extraction of features to differentiate image texture and the classification of images based on information acquired from the frequency domain provides a complementary method to approaches based within the spatial domain. The intensity, I, of the Fourier transformed images can be modeled by an equation of power law form, I = Ar?, where A and ? are constants and r is the radial spatial frequency. The power law is fitted over annuli, centred at zero spatial frequency, and the parameters, A and ?, determined for each spatial frequency range. The variation of the fitted parameters across wedges of fixed polar angle provides a measure of directionality and the deviation from the fitted model can be exploited for classification. The classification results are combined with an existing method to classify individual objects within the crystallisation drop to obtain an improved overall classification rate.
AB - The two-dimensional Fourier Transform (2D-FT) is well suited to the extraction of features to differentiate image texture and the classification of images based on information acquired from the frequency domain provides a complementary method to approaches based within the spatial domain. The intensity, I, of the Fourier transformed images can be modeled by an equation of power law form, I = Ar?, where A and ? are constants and r is the radial spatial frequency. The power law is fitted over annuli, centred at zero spatial frequency, and the parameters, A and ?, determined for each spatial frequency range. The variation of the fitted parameters across wedges of fixed polar angle provides a measure of directionality and the deviation from the fitted model can be exploited for classification. The classification results are combined with an existing method to classify individual objects within the crystallisation drop to obtain an improved overall classification rate.
KW - Classification
KW - Crystallization images
KW - Fourier transform
KW - Pattern recognition
U2 - 10.1107/S0021889807011156
DO - 10.1107/S0021889807011156
M3 - Article
AN - SCOPUS:34249077238
VL - 40
SP - 418
EP - 426
JO - Journal of Applied Crystallography
JF - Journal of Applied Crystallography
SN - 0021-8898
IS - 3
ER -