Portrait painting requires skills that are inaccessible to novices without artistic training. An AI system would be of great benefit in this occupation. A recent paper proposes a guidance system inspired by conventional portrait drawing procedures.

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Firstly, global guidance helps users to locate facial parts with correct proportions. When the user draws contour lines, the system dynamically searches relevant images from a database and generates a blended image. Then, local guidance helps to design facial details. For this stage, the system generates detailed facial portraits from the contour lines using a GAN-based system and displays one of them. A graphical user interface incorporates the two steps and can switch them freely. A user study verified that the suggested method is useful and satisfactory for users with different levels of drawing skills.
In this paper, we propose dualFace, a portrait drawing interface to assist users with different levels of drawing skills to complete recognizable and authentic face sketches. dualFace consists of two-stage drawing assistance to provide global and local visual guidance: global guidance, which helps users draw contour lines of portraits (i.e., geometric structure), and local guidance, which helps users draws details of facial parts (which conform to user-drawn contour lines), inspired by traditional artist workflows in portrait drawing. In the stage of global guidance, the user draws several contour lines, and dualFace then searches several relevant images from an internal database and displays the suggested face contour lines over the background of the canvas. In the stage of local guidance, we synthesize detailed portrait images with a deep generative model from user-drawn contour lines, but use the synthesized results as detailed drawing guidance. We conducted a user study to verify the effectiveness of dualFace, and we confirmed that dualFace significantly helps achieve a detailed portrait sketch. see this http URL
Research paper: Huang, Z., “dualFace:Two-Stage Drawing Guidance for Freehand Portrait Sketching”, 2021. Link: https://arxiv.org/abs/2104.12297