The density of road network is an important indicator of the accessibility of regional traffic

and obtaining the road pixels in an image is the first step to calculate the density of road network.This study assumes that the spectral characteristic of urban trunk road in high-resolution remote sensing image is consistent along the road direction. A 2D Gabor filter is designed on the basis of the analysis on the angular texture diagram of pixel points and the direction of gray minimum variance.The filtered value group is used as a representation of each pixel.The road pixels are extracted by k-mean clustering segmentation strategy and are refined into the trunk road network. Completion rate

accuracy

and extraction quality are regarded as evaluation indicators of precision and k-mean clustering is used as segmentation strategy.When the segmentation objects are gray value

gray-level co-occurrence matrix

multichannel 2D Gabor filtered value

and the eigenvector adopted in this study

the evaluation results of the completion rate

accuracy

and extraction quality are 0.45

0.51

and 0.37;0.62

0.70

and 0.54;0.58

0.66

and 0.52;and 0.72

0.78

and 0.65

respectively.When the Hough transformation method is used as extraction strategy

the evaluation results of the completion rate

accuracy

and extraction quality are 0.41

0.56

and 0.34 respectively.When the multiscale segmentation method is used as extraction strategy

the evaluation results of the completion rate

accuracy

and extraction quality are 0.41

0.56

and 0.34

respectively.Therefore

in the case of the same segmentation strategy

the segmentation objects adopted in this study can exhibit higher classification accuracy than that of the other objects.Compared with traditional classification methods based on linear or planar characteristics

the method adopted in this study exhibits a certain advantage in terms of accuracy. In this study

a new extraction method of road pixel is proposed

in which the image is segmented by creating a 2D Gabor filtered value group with a specific direction.Experimental results show that this method presents high anti-noise performance and universality and can be applied to the high-resolution remote sensing images from GF-1

GF-2

IKONOS

QuickBird

and other sensors.