Combining Sketch and Tone for Pencil Drawing Production

paper content understanding

algorithm understand

\(Algorithm\quad as\quad following\)

• line drawing with stoke
  • gradient map \(G\) of \(img\)
    • \(G = \sqrt{(\frac{\partial img}{\partial x})^{2} + (\frac{\partial img}{\partial y})^{2}}\)
  • using convolution compute to get the response map
    • \(G_{i} = L_{i} * G\)
    • \(L_{i}\) is the \(i_{th}\)convolution filter, \(*\) is convolution compute
  • save maximum of each pixel in \(G_{i}\) to \(C_{i}\)
    • \(C_{i} = if\quad (argmin_{i}G_{i} == i)\quad then\quad G_{i}\quad else\quad 0\)
  • sum up of \(C\) then get line drawing with stoke
    • \(S = \sum_{i}{L_{i} * C_{i}}\)
• texture
  • separate \(img\) tone as 3 levels
    • high level(bright) - Laplacian distribution
      • \(p_{1}(v) = if\quad (v\le 1)\quad \frac{1}{\sigma_{b}}e^{-\frac{1 - v}{\sigma_{b}}}\quad else\quad 0\)
    • middle level - average distribution
      • \(p_{2}(v) = if\quad (u_{a}\le v \le u_{b})\quad \frac{1}{u_{a} - u_{b}}\quad else\quad 0\)
    • low level(dark) - Gaussian distribution
      • \(p_{3}(v) = \frac{1}{\sqrt{2\pi \sigma_{d}}}e^{-\frac{(v - \mu_{d})^{2}}{2\sigma_{d}^{2}}}\)
  • sum up of 3 level map above
    • \(p(v) = \frac{1}{Z}\sum_{i = 1}^{3}\omega_{i}p_{i}(v)\)
    • \(\omega_{i}\) is parameter that empower \(p_{i}(v)\)
  • \(H\) is style map of pencil drawing, fitting \(J\) using \(H\), \(H(x)^{\beta(x)} \approx J(x)\)
    • \(\beta^* = argmin_{\beta}||\beta \ln H - \ln J||_{2}^{2} + \lambda||\nabla\beta||_{2}^{2}\)
  • get pencil drawing textual map
    • \(T = H^{\beta^*}\)
• stack 2 section above together, get output pencil drawing of \(img\)
  • \(R = S·T\)

report outlines

• abstract
• related work
• our model
• comparison
• ending remarks

paper writing strategies note

Abstract

Para.1

• We propose …

我们提出了…

• … is also incorporated in

… 被添加了进来

Introduction

Para.1

• … is one of the most fundamental … in

说明重要性

• Pencil method general fall into two categories，

Pencil 方法大致分为两类

• The majority of … resorts to …

… 大部分的依靠…付诸实现（诉诸于完成）

• Consequently，

因此，

• substantial increase

大量的增长

Para.2

• In the literature,

在文献中，

• ~ is effortless

~ 毫不费力， 容易做得到

• accurately extracting and manipulating structures

精确提取和操作结构
\(e.g.\) It is because accurately extraction and manipulating structures, which is almost effortless using 3D models with unknown boundary and geometry, becomes challenging due to the existing of texture, noise, and illumination variation.

• spurious noise-like structures

虚假的噪声结构

• without ……, … become difficult

强调 … 的重要性

• … risk …

… 可能会导致
\(e.g.\) Adding directional hatching patterns using closely placed parallel lines risks laying them across different surfaces and depth layers, causing unnatural drawing effects.

Para.3

• … is paramount in … (doing)

… 在 … 中至关重要

• on the inherent difficulty to

固有的困难

Para.4

• differ out method from existing approaches

我们的方法与已有的方法相区别开

Related Work