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Docume entation: Ca aren-Maria Jörß 29.01.2012 / Englissh: August 2012 2

Textu ureMan (Freak Client V V1) Progra am developer: Chris stian Tonn n  

1. Introduction – the aim ms of Tex xtureMan eMan can be e used to sy ynthesize d ifferent texttures. Using g a single im mage as a source, s Texture Texture eMan can crreate a textu ure that is o only slightly different to o the originaal. TextureM Man can create ttextures using differentt methods, m making it po ossible to sy ynthesize a larger structure from a smaller structure.

2. Use er interfac ce

n user interfface Fig. 1 TextureMan Window w, top left: Central window:

View of the originall image Output window w

3. Tuto orial This tuto orial provide es an overv view of the d different tex xture synthe esizing apprroaches and creates a structurre for each. Start Textu ureMan and follow the steps s 1 to 4 as shown in the program’s user interface e.

3.1. Ste ep 1 – Deffine Sourc ce Image To synthesise a ne ew texture, a source im mage is requ uired. Click the button ““Load image” and the import the image “sstein.jpg”. The T image sshows in the e panel at th he top left. For eacch open or created c image, a separrate tab will show abov ve the outpuut window with w which itt is possible e to switche ed between the individu ual synthesis results. Here H one caan also see the size of each of the imagess. In this exa ample we h have chosen n an image size of 2000 × 200 pixe els. Using th he button “L Load feature e image”, a n additional image can n be uploadeed (“steinSW W.jpg”) thatt can help p to improve e the quality y of the syn nthesized te exture. This additional iimage only works in conjuncction with the “Tonn (20 007)” synthe esis method d (chosen in n step 2.5). The “Fe eature image” is a black and white e image thatt highlights the particullar characte eristic of the e structurre. The featu ure image for f this tutorrial shows th he cobblesttones in blaack and the grouting between n them in white. w

Feature ima age Fig. 2 F The “Ca apture Camera Image” loads an im mage from an a attached d camera intto the progrram. To delete the source image from the program m, choose the t button “Delete sourrce tab”.

3.2. Ste ep 2 – Deffine Sourc ce Area equired to create the sy ynthesized ttexture, clic ck the button If only a section of the source image is re ”Define source area” and mark the desire ed area in th he source im mage windoow. The deffault setting is the entire source im mage.

3.3. Ste ep 2.5 – Synthesis Parameter P rs The nexxt step is to choose a synthesis s al gorithm and d the size of o the outputt window. The T menu fo or this step p is located to the rightt of the outp put window. 1. “Syntthesis Algorrithm” By ch hoosing diffferent synth hesis calcula ation algoritthms you ca an produce different en nd results: Imag ge Tiling: Th he source im mage is dup plicated and d replicated to fit along its edges. Mirro ored Tiling: The origina al image is m mirrored and arranged sequentiallly. Efos et al. (1999 9) 1: The tex xture is exte ended outw wards. This approach a iss very protra acted. The algorrithm search hes in the source s imag ge for pixels s with simila ar surroundiings, constrructs a list out o of the eses and ad dds new pix xels chosen n randomly from the list. The outpuut paramete er “Compare e entially rele window” definess the area in n which pote evant pixels will be seaarched.

Ashikkhmin (2001)2: To begin with a ran ndom noise e is applied to the imagge. The algo orithm then lookss at each pixel and exa amines whicch other pix xel fits best. This also ssupports the e “Compare e window” function. 3 Lefeb bvre et al. (2006) ( : To begin with a preliminary computation is execcuted to gen nerate pixel groups that also o occur in th he original. T The followin ng calculatio ons are theen processe ed in severa al passses: from low w to higher resolution. This approach supporrts the autom matic “Feature Detectio on” and ““Compare window” w fun nctions.

Tonn n (2007): Th his approach extends L Lefebvre synthesis metthod by addding a furthe er function. The Feature Ima ages can be e added ma anually. The e manual ad ddition of feeature images can impro ove the precision of the e synthesiss.

2. “Outp put Parameter” Outp put Resolutiion: the size e of the text ure to be sy ynthesized, for exampl e 400 × 400 0 pixel. Com mpare Windo ow: window size for the e pixel comparison (e.g g. 15 x 15 ppixel) Initia al Random Number: N de efines a starrt value for the t random number geenerator use ed.

3. “Featture Detectiion” This function au utomatically recognisess the structu ural charactteristics of thhe source image.

3.4. Ste ep 3 – Run n Texture Synthesis s The com mmand “Run Texture Synthesis” S sstarts the te exture synthesizing proocess. The progress p ba ar beneath h the outputt window giv ves an indiccation of ho ow long the process maay take. The e following screensshots show a series of different ressults for the e individual synthesis aalgorithms using u the same so ource image e.

Fig. 3 IImage Tillin ng

Fig. 4 M Mirrored Tiling

Fig. 5 E Efos et al. (1999) (

Fig. 6 A Ashikhmin (2001) (

Lefebvre et al. (2006) Fig. 7 L

Fig. 8 T Tonn (2007 7)

3.5. Ste ep 4 – Res sult The finisshed computed texture e can be sa aved for futu ure use usin ng the “Savee” button (im mage forma ats: JPG or BMP). Clickk “Delete Result Tab” tto remove the individua al output wi ndows. When yyou are finisshed, click “Done” to en nd the progrram.

4. Refe ferences 1

ASHIK KHMIN, M., 2001. Syntthesizing Na atural Textu ures. In: J.F F. Hughes aand C. H. Sé équin, eds. The pro oceedings of o 2001 ACM M Symposiu um on Intera active 3D Graphics, G Neew York: AC CM Press, 217-226 6 or http://w www.cs.utah hael/ts : July y 2007. 2

EFRO OS, A.A. and d LEUNG, T.K., T 1999. Texture Syn nthesis by Non-parame N etric Samplling. In: John K. Tsotssos, ed. IEE EE Internatiional Conferrence on Computer Vis sion. Corfu:: IEEE Com mputer Society, y, 1033-1038 8. 3

LEFEB BVRE, S. AND A HOPPE E, H., 2006.. Appearanc ce-space te exture synthhesis. In: Prroceedings of ACM SIIGGRAPH 2006, 2 New York: ACM M Press, 544 4-548 or http p:// July 200 07.

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