  We propose a novel image-to-pencil translation method that could not only
generate high-quality pencil sketches but also offer the drawing process.
Existing pencil sketch algorithms are based on texture rendering rather than
the direct imitation of strokes, making them unable to show the drawing process
but only a final result. To address this challenge, we first establish a pencil
stroke imitation mechanism. Next, we develop a framework with three branches to
guide stroke drawing: the first branch guides the direction of the strokes, the
second branch determines the shade of the strokes, and the third branch
enhances the details further. Under this framework's guidance, we can produce a
pencil sketch by drawing one stroke every time. Our method is fully
interpretable. Comparison with existing pencil drawing algorithms shows that
our method is superior to others in terms of texture quality, style, and user
evaluation.
