杨铁滨 侯玉婷 刘一星 薛伟
摘要:实现木材机械加工表面质量自动评价对保证木制品质量和提升其价值有重要意义。根据ASTM_D_1666-87R04标准中规定的测试方法,对樟子松、白桦、水曲柳板材进行压刨和砂光加工试验,得到有Raised grain、Fuzzy grain、Chip marks缺陷和无缺陷的木材试样。扫描木材试样以获取其表面图像,计算图像的直方图纹理特征和小波纹理特征。对每种特征分别建立基于BP神经网络的分类器并进行训练和测试。测试结果表明,小波纹理特征分类器的正确率达到91.3%,其评价效果优于直方图纹理特征分类器。
关键词:木材加工;表面质量;自动评价;小波纹理分析
中图分类号:[S 777];[TH 161+.14]文献标识码:A文章编号:1001-005X(2015)01-0059-04
Imagebased Evaluation of Machining Wood Surface Quality
Yang Tiebin,Hou Yuting,Liu Yixing*,Xue Wei
(College of Engineering and Technology,Northeast Forestry University,Harbin 150040)
Abstract:Automated evaluation of machining wood surface quality plays an important role in the overall quality and value of wood products.According to the test methods of ASTM_D_1666-87R04,this paper practiced planning and sanding tests on Mongolian Scotch Pine,Asian White Birch and Manchurian Ash lumbers.Raised grain,Fuzzy grain,Chip marks and defect free samples were obtained.The surface images of the sample were captured by scanning.Histogram texture features and wavelet texture features were retrieved from those surface images.Two BP ANNs were developed and tested according to these two kinds of features separately.The test results showed that the wavelet texture feature classifier achieved an accuracy of 91.3% which is much better than the performance of histogram features classifier.
Keywords: wood machining;surface quality;automated evaluation;wavelet texture analysis
收稿日期:2014-09-26
基金項目:黑龙江省博士后基金资助项目(LBH-Z09283)
第一作者简介:杨铁滨,博士,副教授。研究方向:森工机械与装备。
*通讯作者:刘一星,博士,教授。研究方向:木材科学与技术。Email:yxl200488@sina.com
引文格式:杨铁滨,侯玉婷,刘一星,等.基于图像的木材机械加工表面质量评价研究[J].森林工程,2015,31(1):59-62.在木材生产中,提高木制品表面质量是提升产品价值最经济、有效的方式之一,具有重要的意义。观测表面缺陷是评价木材机械加工表面质量的主要方法之一[1-2]。
对于特定的树种,加工参数选择不当,可能产生多种形式的表面缺陷。在ASTM_D_1666-87R04标准中定义了Raised grain、Fuzzy grain、Torn grain 和Chip marks四种表面缺陷。根据表面缺陷的深度、面积、数量和形式,用人工视觉的方法将表面质量分为excellent、good、fair、poor和very poor等5个等级[3]。这种方法主观依赖性强,对检测者的经验要求较高,劳动强度大,不利于机械化生产。……