Image-based irregular needling embroidery rendering

Abstract

Irregular needling embroidery has a very high artistic value as a Changzhou craftwork. Artists use stitches of rich colors and apply different types of stitch categories from course to fine on multiple layers to express objects. This paper proposes an irregular needling embroidery rendering method based on image. We first decompose the image into different regions, vector fields and image detail information to guild the subsequent simulation process. Then we hierarchically render the image with a series of layers and propose a multilayer rendering technique. Additionally, we build a stitch dictionary and present a method to simulate the threads. Experimental results demonstrate that the method proposed in this paper transfers reference images quickly and efficiently into their irregular needling embroidery simulations.

Image‐based embroidery modeling and rendering

“…As can be seen, Yang et al . and Chen et al . used the 2D thread model and thin cylinder model, respectively, while we use the 3D ellipsoid model, which makes the stitches rendering better.…”

“…If the size of stitches is set to be excessively small, more details in the input image can be preserved, but this will deteriorate the rendering effect because small stitches are visually indistinguishable. We adopt the formula with respect to the stitch length and areas of segmented regions , where ω = m a x ( i n p u t w i d t h , i n p u t h e i g h t )/50, A ( r e g i o n ) denotes the region area, and M a x A ( i n p u t ) and M i n A ( i n p u t ) denote the maximum and minimum areas of all the segmented regions in the input image, respectively. The stitch width is set to 0.2∗ l e n g t h empirically.…”

“…modeled the long‐short stitch, satin stitch, and edge stitch of the traditional embroidery , while Yang et al . simulated both the crossover stitch and triangle stitch . The stitch patterns implemented in this paper are similar to those in , but the key difference is that we use a real 3D stitch model, which allows us various lighting simulations.…”

“…Yang et al . proposed an image‐based method to simulate the Chinese irregular needling embroidery by constructing a stitch dictionary with a multilayer rendering technique to produce vivid and colorful results . To make stitches visually compelling, Chen et al .…”

“…assumed the thread to be a thin cylinder and used a technique called tangent modification with alpha blending , while Yang et al . used a planar stitch model and performed a simple tuning of intensity over the stitches . However, the fixed shading in failed to consider the lighting effect when rendering the stitches, resulting in incoherent shading effects.…”