Pencil drawing is an important artistic style which is widely used in draft sketch and finished rendering. It is non-trivial if we can automatically generate the pencil drawing more precisely in order to ease the human efforts. In this paper, we propose flow-guided sketch and accentuated-tone adjusting techniques to transform the pencil drawing from natural images. This work is extended from the existing pencil drawing framework where authors combine sketch and tone together for penciling purpose. Through an edge tangent flow guided classification and convolution, we can obtain more coherent and smooth strokes, especially for portraits. In addition, we also introduce a hierarchical approach to generate strokes. According to saliency map, we can adjust the tone of images automatically. The experimental results indicate the generated toned pencil drawings by our approach are of fewer artifacts and could even solve the images with dark background
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