特徴抽出
WordNet
- an article of merchandise that is displayed or advertised more than other articles
- a prominent attribute or aspect of something; "the map showed roads and other features"; "generosity is one of his best characteristics" (同)characteristic
- a special or prominent article in a newspaper or magazine; "they ran a feature on retirement planning" (同)feature article
- the principal (full-length) film in a program at a movie theater; "the feature tonight is `Casablanca" (同)feature film
- the characteristic parts of a persons face: eyes and nose and mouth and chin; "an expression of pleasure crossed his features"; "his lineaments were very regular" (同)lineament
- the process of obtaining something from a mixture or compound by chemical or physical or mechanical means
- the action of taking out something (especially using effort or force); "the dentist gave her a local anesthetic prior to the extraction"
- made a feature or highlight; given prominence; "a featured actor"; "a featured item at the sale"
- having facial features as specified; usually used in combination; "a grim-featured man"
PrepTutorEJDIC
- 顔の造作の一つ(目・耳・鼻・口など) / 《複数形で》『容ぼう』,目鼻だち / 『特徴』,特色 / (ラジオ・演芸などの)『呼び物』;(店の)目玉商品;(新聞・雑誌の)特別読み物;(映画の上映番組の中で呼び物の)長編映画 / …‘の'『特色をなす』 / …‘を'特種にする,呼び物にする,目玉商品にする / 〈俳優〉‘を'主演させる / 重要な役割を演ずる
- 〈U〉〈C〉引き出すこと,抜き取ること,摘出 / 〈C〉引き出されたもの,抜き取られたもの,抽出物,エキス;抜粋 / 〈U〉生まれ,皿統
Wikipedia preview
出典(authority):フリー百科事典『ウィキペディア(Wikipedia)』「2015/12/09 03:16:45」(JST)
[Wiki en表示]
In machine learning, pattern recognition and in image processing, feature extraction starts from an initial set of measured data and builds derived values (features) intended to be informative and non-redundant, facilitating the subsequent learning and generalization steps, and in some cases leading to better human interpretations. Feature extraction is related to dimensionality reduction.
When the input data to an algorithm is too large to be processed and it is suspected to be redundant (e.g. the same measurement in both feet and meters, or the repetitiveness of images presented as pixels), then it can be transformed into a reduced set of features (also named a "features vector"). This process is called feature extraction. The extracted features are expected to contain the relevant information from the input data, so that the desired task can be performed by using this reduced representation instead of the complete initial data.
Contents
- 1 General
- 2 Image processing
- 2.1 Low-level
- 2.1.1 Curvature
- 2.1.2 Image motion
- 2.2 Shape based
- 2.3 Flexible methods
- 3 Feature extraction in software
- 4 See also
- 5 References
General
Feature extraction involves reducing the amount of resources required to describe a large set of data. When performing analysis of complex data one of the major problems stems from the number of variables involved. Analysis with a large number of variables generally requires a large amount of memory and computation power or a classification algorithm which overfits the training sample and generalizes poorly to new samples. Feature extraction is a general term for methods of constructing combinations of the variables to get around these problems while still describing the data with sufficient accuracy.
The best[citation needed] results are achieved when an expert constructs a set of application-dependent features, a process called feature engineering. Nevertheless, if no such expert knowledge is available, general dimensionality reduction techniques may help. These include:
- Principal component analysis
- Semidefinite embedding
- Multifactor dimensionality reduction
- Multilinear subspace learning
- Nonlinear dimensionality reduction
- Isomap
- Kernel PCA
- Multilinear PCA
- Latent semantic analysis
- Partial least squares
- Independent component analysis
- Autoencoder
Image processing
One very important area of application is image processing, in which algorithms are used to detect and isolate various desired portions or shapes (features) of a digitized image or video stream. It is particularly important in the area of optical character recognition.
Low-level
- Edge detection
- Corner detection
- Blob detection
- Ridge detection
- Scale-invariant feature transform
Curvature
- Edge direction, changing intensity, autocorrelation.
Image motion
- Motion detection. Area based, differential approach. Optical flow.
Shape based
- Thresholding
- Blob extraction
- Template matching
- Hough transform
- Lines
- Circles/ellipses
- Arbitrary shapes (generalized Hough transform)
- Works with any parameterizable feature (class variables, cluster detection, etc..)
Flexible methods
- Deformable, parameterized shapes
- Active contours (snakes)
Many data analysis software packages provide for feature extraction and dimension reduction. Common numerical programming environments such as MATLAB, SciLab, NumPy and the R language provide some of the simpler feature extraction techniques (e.g. principal component analysis) via built-in commands. More specific algorithms are often available as publicly available scripts or third-party add-ons.
See also
- Cluster analysis
- Dimensionality reduction
- Feature detection
- Feature selection
- Data mining
- Connected-component labeling
- Segmentation (image processing)
References
UpToDate Contents
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English Journal
- Modification of xylan in alkaline treated bleached hardwood kraft pulps as classified by attenuated total-internal-reflection (ATR) FTIR spectroscopy.
- Chen Z1, Hu TQ2, Jang HF2, Grant E3.
- Carbohydrate polymers.Carbohydr Polym.2015 Aug 20;127:418-26. doi: 10.1016/j.carbpol.2015.03.084. Epub 2015 Apr 24.
- The glucuronoxylan composition of a pulp affects the bonding between cellulosic fibres, and thus correlates with such network properties as tensile strength. Here, we demonstrate the promise of attenuated total-internal-reflection (ATR) FTIR spectroscopy as a rapid means for classifying the xylan co
- PMID 25965501
- High-resolution face verification using pore-scale facial features.
- Li D, Zhou H, Lam KM.
- IEEE transactions on image processing : a publication of the IEEE Signal Processing Society.IEEE Trans Image Process.2015 Aug;24(8):2317-27. doi: 10.1109/TIP.2015.2412374. Epub 2015 Mar 12.
- Face recognition methods, which usually represent face images using holistic or local facial features, rely heavily on alignment. Their performances also suffer a severe degradation under variations in expressions or poses, especially when there is one gallery per subject only. With the easy access
- PMID 25781876
- Support vector machine and fuzzy C-mean clustering-based comparative evaluation of changes in motor cortex electroencephalogram under chronic alcoholism.
- Kumar S1, Ghosh S, Tetarway S, Sinha RK.
- Medical & biological engineering & computing.Med Biol Eng Comput.2015 Jul;53(7):609-22. doi: 10.1007/s11517-015-1264-0. Epub 2015 Mar 13.
- In this study, the magnitude and spatial distribution of frequency spectrum in the resting electroencephalogram (EEG) were examined to address the problem of detecting alcoholism in the cerebral motor cortex. The EEG signals were recorded from chronic alcoholic conditions (n = 20) and the control
- PMID 25773367
Japanese Journal
- RESEARCH OF THE COMBINATION OF GEOMETRIC ALGEBRA FEATURE EXTRACTION AND ELASTIC NET PENALTY BASED LOGISTIC OR MULTINOMIAL MODEL
- WANG JINJIA,LU YANG,LU HAITAO [他]
- ICIC express letters. Part B, Applications : an international journal of research and surveys 5(6), 1601-1605, 2014-12
- NAID 40020068708
- 実空間及び周波数空間における画像特徴量を用いた顔認識
- 小林 積博,陳 キュウ
- 工学院大学研究報告 (117), 39-44, 2014-10-30
- … When performing facial recognition, the feature of a facial image is extracted and compared. … LBP(Local Binary Pattern) is used for extraction of features in spatial domain and two-dimensional DCT conversion for frequencydomain. …
- NAID 110009839857
- ウェアラブル端末・スマートフォンを利用した生活行動認識の分散処理方式
- 大橋 純,須藤 隆,大内 一成,斉藤 龍則
- 情報処理学会研究報告. HCI, ヒューマンコンピュータインタラクション研究会報告 2014-HCI-160(10), 1-8, 2014-10-07
- スマートフォンのマイクから取得した音データを使用して生活行動を認識する技術が提案されている.従来技術では,例え自宅内であっても常にスマートフォンを保持して生活しなければならず,より携帯性の高いウェアラブル端末を利用した生活行動認識技術の確立が望まれている.しかしながら,音を使用した行動認識手法は計算量が多く処理性能が低いウェアラブル端末で動作させることは困難だった.本論文では,計算量とデータ通信量 …
- NAID 110009831866
Related Links
- マイクロアレイの画像を簡単に処理 アジレントの Feature Extraction ソフトウェア 12.0 は、最大 100 個のマイクロアレイ画像ファイルを自動で読み取り、処理します。このソフトウェアは、マイクロアレイのスポット位置の認識、異常 ...
- Learn about feature extraction for computer vision with MATLAB. Resources include examples, webinars, and documentation covering computer vision concepts. ... Feature extraction for compact representation of image data in ...
★リンクテーブル★
[★]
- 顔の造作の一つ(目・鼻・口・耳・額・あごなど)
- [pl]顔(the face)、容貌、顔立ち、目鼻立ち、眉目
- (山・川などの)布置、地勢、地形
- (著しい)特徴、特色。主要点
- (言語)素性、特徴
- 関
- attention, character, characteristic, distinction, focus, hallmark, note, notice, particular, property, salience, trait
[★]
- 引き抜くこと、抽出すること、抽出されること。(鉱物の)採取
- 抽出された物。エキス、抜粋
- 血統、家系
- 抜糸