Study On Wood Structure Aesthetics Based On 1/f Fluctuation

In order to deplore the principle of wood aesthetics, variation regularities of wood structure were discussed at the angle of frequency ranges. Based on the principle of rhythm equalization effect, and combined with heartbeat and brain wave rhythm, aesthetic principle of wood structure was analyzed. Taking the wood structure images of cross section of different magnification, images of three planes (cross-, tangential-, and radial-section) of 40 times, transverse images of 40 times with different pore arrangement patterns, and gross grain pictures of 9 commonly used wood species as study materials, imitation degree (R), power spectrum parameter (γ) and beauty index (η) were calculated for all the wood images and pictures, and their fluctuation characters were analyzed. The main results are as follows.1. According to the fluctuation characters of wood structure, the beauty values of wood structure images were analyzed in present study, and the results basically conform to the common appreciation conceptions on wood structure images. The beauty index (η) constructed in this study can be used to evaluate the beauty values of wood structure images.2. Through the systematic analysis on the wood structure images of cross section of different magnification, images of three planes (cross-, tangential-, and radial-section) of 40 times, transverse images of 40 times with different pore arrangement patterns, and gross grain pictures of 9 commonly used wood species, results showed that the imitation degree (R) of the power spectrum of all the wood images reached 0.8 upwards. This means that there is quite good linear relationship between the density of power spectrum and frequency.3. The results of this study showed that the power spectrum parameters (y) of all wood structure images studied in this paper ranged 0.5-1.5, most of them ranged 0.85-1.15, showing typical 1/f fluctuation. Why people could obtain pleasant and comforTab. feelings from wood structure images? Based on the results of fluctuation spectrum analysis, the fundamental reason is that there is a good linear relationship between the power spectrum of wood structure images and frequency, showing typical 1/f fluctuation and exciting pleasant a wave in the human brain.4. According to the results of fluctuation analysis, generally, the aesthetic value of porous wood images was higher than that of softwood images. There were quite large differences between fluctuation characters of wood images on different planes of the same tree, and the differences were much more significant in porous wood. To porous wood, the beauty indexes (η) of different planes generally showed:ηc> ηt> ηr. The beauty indexes (η) of softwood, on the whole, were lower than those of porous wood, and showed:ηr> ηt> ηc.5. To the cross section images of porous wood, generally, the beauty indexes of ring-porous, tangentially arranged porous and flower type porous wood were larger than those of diffuse and radially arranged porous wood.6. Magnification of wood structure images showed no necessary influence upon the results of fluctuation analysis. But as magnification increased, the actual wood surface area included in the analyzed field decreased. For this reason, when magnification increased to certain degree, the image included in the analyzed field failed to show the whole structure of the wood, and therefore, the accuracy of the result would be affected.7. There is difference in aesthetic appreciation between different people, when selecting wood decoration material, people needs to have a comprehensive consideration upon imitation degree (R), power spectrum parameter (y) and beauty index (η) of wood structure pictures. Generally speaking, the closer the three parameters (R, γ,η) to 1, the higher the beauty value of the wood structure picture.