SwiftSketch: A Diffusion Model for Image-to-Vector Sketch Generation

TL;DR

SwiftSketch is a fast diffusion model that generates high-quality, image-conditioned vector sketches in under a second, overcoming the slow optimization of previous methods.

Contribution

It introduces SwiftSketch, a novel diffusion-based approach with a transformer-decoder architecture for rapid, high-quality vector sketch generation conditioned on images.

Findings

Generates sketches in less than a second.

Produces high-fidelity, natural sketches.

Generalizes across diverse concepts.

Abstract

Recent advancements in large vision-language models have enabled highly expressive and diverse vector sketch generation. However, state-of-the-art methods rely on a time-consuming optimization process involving repeated feedback from a pretrained model to determine stroke placement. Consequently, despite producing impressive sketches, these methods are limited in practical applications. In this work, we introduce SwiftSketch, a diffusion model for image-conditioned vector sketch generation that can produce high-quality sketches in less than a second. SwiftSketch operates by progressively denoising stroke control points sampled from a Gaussian distribution. Its transformer-decoder architecture is designed to effectively handle the discrete nature of vector representation and capture the inherent global dependencies between strokes. To train SwiftSketch, we construct a synthetic dataset of image-sketch pairs, addressing the limitations of existing sketch datasets, which are often created by non-artists and lack professional quality. For generating these synthetic sketches, we introduce ControlSketch, a method that enhances SDS-based techniques by incorporating precise spatial control through a depth-aware ControlNet. We demonstrate that SwiftSketch generalizes across diverse concepts, efficiently producing sketches that combine high fidelity with a natural and visually appealing style.