Image stylization using anisotropic reaction diffusion

An implementation of paper's system

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Abstract

Image stylization refers to the process of converting input images to a specific representation that enhances image content using several designed patterns. The critical steps to a successful image stylization are the design of patterns and arrangements. However, only skilled artists master such tasks because these tasks are challenging for most users. In this paper, a novel image stylization system based on anisotropic reaction diffusion is proposed to facilitate pattern generation and stylized image design. The system begins with self-organized patterns generated by reaction diffusion. To extend the style of reaction diffusion, the proposed method involves using a set of modifications of anisotropic diffusion to deform shape and introducing a flow field to guide pattern arrangement. A pattern picker is proposed to facilitate the pattern selection from these modifications. In the post-process step, a new thresholding and color mapping method is introduced to refine the sizes, densities, and colors of patterns. From the experimental results and a user study, several image stylizations, including paper-cut, stylized halftone, and motion illusion, are generated using our method, demonstrating the feasibility and flexibility of the proposed system.

Keywords: Non-photorealistic, rendering, Image stylization, Reaction diffusion, Pattern generation

Demo

youtube link

[Required]

• CMake(3.0 or higher)
• wxWidgets(3.0.2 or higher)
• OpenCV(2.9.7 or higher)
• amp(C++ Accelerated Massive Parallelism)

[WorkFlow]

• Open src: Load image into MASK, and generate sobel edge image into MASK_s
• Flowfield Option:

1. Open ETF: use the ETF of load image as flowfield
2. Open Flow: there are some vfb in /data/

• Start: use mouse left button to draw patten into current_B, use tool->Edge2addB and slide addB large than 0, can add edge of input image to result of reaction diffusion.

[Future Work]

2. using faster algorithm
3. oriental cloud patterns
4. merge flowfield maker
5. parameter f

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[Papers' Examples]

Fig.	Workflow	Remark/Notes
4(a)	Load Flow source.vfb, Parameters F k l can reference to Table 1, Press Start and click Fill Ink, after its being stable, select adathresholding (beta=0.8)	--
4(b)	as above	--
4(c)	as above	--
5(a)	Load Flow vortex.vfb, Parameters F k l can reference to Table 1, check the Customize Anisotropic Function to YES, and select 0~180 degree. Then press Start and click Fill Ink, after its being stable, select adathresholding (beta=0.8, alpha=0.1)	--
5(b)	as above, Customize Anisotropic Function select degree 0~180.	--
5(c)	as above, Customize Anisotropic Function select degree 45~135.	--
8(c)	Load SrcImg controlshape-a.png, Load Flow vortex.vfb, Load Control Img controlshape_controlImg.png. Press Start, Pattern Size = 0.1, then check the Activate Segmentation to YES, and assign each region with its own parameters(recommanded pattern provide at Note). After its stable , select Thresholding (alpha=0.4 beta=0.5).	Region 1:SPOT(theta0=90) 2:HOLE(theta0=90) 3:SPOT(theta0=90) 4:LINE(theta0=90) 5:inverse LINE(theta0=90)
12(c)	Load SrcImg cat-source.png, Load ETF cat-source.png, The Parameters can use Pattern Picker (Tool>Open Pattern Picker) to select SQUARE pattern, then Press Start and click Fill Ink and click Edge2AddB (Tool>Edge2AddB), after its being stable, select adathresholding (alpha=0.4 beta=0.0)
12(d)	as above, use gradient size (size type: LINEAR) brush to modify the sizes
14(c)	Load SrcImg flower.png, Load Flow vortex.vfb, The Parameters can use Pattern Picker (Tool>Open Pattern Picker) to select SQUARE pattern, then Press Start and click Fill Ink, use gradient size (size type: inverse Circular) brush to modify the sizes, after its being stable, select colormapping (Mode: 3)
14(d)	as above, use gradient k (size type: inverse Circular) brush to modify the pattern parameters
15(c)	Load SrcImg Marilyn.png, Load Flow vortex.vfb, The Parameters can use Pattern Picker (Tool>Open Pattern Picker) to select SPINDLE pattern, then Press Start and click Fill Ink, after its being stable, select adathresholding (alpha=0.4 beta=0.0)
15(e)	as above, replace Flow by using ETF of Marilyn.png, and choose the SQUARE pattern
17(c)	Load SrcImg Kremlin-source.png, Load ETF Kremlin-source.png, Load Control Img Kremlin-controlImg.png. Press Start and click Edge2AddB (addB=0.03), then check the Activate Segmentation to YES, and assign each region with its own parameters(recommanded pattern provide at Note). After its stable , select Thresholding (alpha=0.05 beta=0.4).	Region 1:SPOT 23: BLACK 48: LINE
17(d)	as above.Pattern Size = 0.2 After its stable , select adaThresholding (alpha=0.36 beta=0.4).	Regions 13: HOLE 48: QUADE(theta0=45)

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[Table 1]

Style	a(theta)	F	k	l	Figure
semicircle	Eq. 6	.0375	.0655	1	Fig. 5(a)
spot: spidle	Eq. 6	.0375	.0655	2	Fig. 5(b)
hole: spidle	Eq. 6	.0300	.0546	2	Fig. 8 blue
stripe	Eq. 6	.0300	.0620	2	Fig. 8 green
triangle	Eq. 6	.0375	.0655	3	Fig. 5(c)
spot: quad	Eq. 6	.0375	.0655	4	Fig. 5(d)
water drop	Eq. 7	.0375	.0655	2	Fig. 6(a)
sector	Eq. 7	.0375	.0655	4	Fig. 6(b)

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Common Q&A

Q: Error LNK2019(Build Error)

Open VS2013 Project settings -> Linker > General > System : change Subsystem to "Windows".

Q: Unable to startup program (The system cannot find the file specified)(Build Error)

Solution Explorer -> Select "FlowBase" -> Right Click and "Set as StartUp Project"

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Citation

@article{chi2016image,
  title={Image stylization using anisotropic reaction diffusion},
  author={Chi, Ming-Te and Liu, Wei-Ching and Hsu, Shu-Hsuan},
  journal={The Visual Computer},
  volume={32},
  number={12},
  pages={1549--1561},
  year={2016},
  publisher={Springer}
}