7.10.7 Filter Approaches to Texture

Chapter Contents (Back)
Textures, Filters. See also Texture Segmentation Using Filters.

Apostolico, A., Caianiello, E.R., Fischetti, E., Vitulano, S.,
An Application of C-Calculus to Texture Analysis: C-Transforms,
PR(10), No. 5-6, 1978, pp. 389-396.
WWW Version. BibRef 7800

Caianiello, E.R., Gisolfi, A., Vitulano, S.,
A Technique for Texture Analysis Using C-Calculus,
SP(1), 1979, pp. 159-173. BibRef 7900

Wechsler, H.[Harry], Citron, T.[Todd],
Feature extraction for texture classification,
PR(12), No. 5, 1980, pp. 301-311.
WWW Version. 0309
BibRef

Ade, F.,
Characterization of Textures by 'Eigenfilters',
SP(5), 1983, pp. 451-457. BibRef 8300

Beck, J., Sutter, A., and Ivry, R.,
Spatial Frequency Channels and Perceptual Grouping in Texture Segregation,
CVGIP(37), No. 2, February 1987, pp. 299-325.
WWW Version. BibRef 8702

Bergen, J.R., and Adelson, E.H.,
Early Vision and Texture Perception,
Nature(333), 1988, pp. 363-367. Textures are similar (to people) when similar response in a bank of filters (e.g. Gabor). BibRef 8800

Montes, J., Cristobal, G., Bescos, J.,
Texture Isolation by Adaptive Digital Filtering,
IVC(6), No. 3, August 1988, pp. 189-192.
WWW Version. BibRef 8808

Waksman, P.[Peter], Greene, E.[Ernest],
Optical image encoding and comparing using scan autocorrelation,
US_Patent4,745,633, May 17, 1988
WWW Version. BibRef 8805

Kundu, A.[Amlan], Chen, J.L.[Jia-Lin],
Texture Classification Using QMF Bank-Based Subband Decomposition,
GMIP(54), No. 5, September 1992, pp. 369-384. BibRef 9209

Coggins, J.M., and Jain, A.K.,
A Spatial Filtering Approach to Texture Analysis,
PRL(3), 1985, pp. 195-203. BibRef 8500

He, D.C.[Dong-Chen], Wang, L.[Li],
Textural filters based on the texture spectrum,
PR(24), No. 12, 1991, pp. 1187-1195.
WWW Version. 0401
BibRef

Olstad, B.[Bjørn],
Reasoning with entropy graphs for image operators,
PR(26), No. 8, August 1993, pp. 1255-1275.
WWW Version. 0401
Structuring of large sets of image operators. For Segmentation. BibRef

Shang, C.J.[Chang-Jing], Brown, K.[Keith],
Principal features-based texture classification with neural networks,
PR(27), No. 5, May 1994, pp. 675-687.
WWW Version. 0401
BibRef

Shang, C.J.[Chang-Jing], Shen, Q.A.[Qi-Ang],
Rough Feature Selection For Neural Network Based Image Classification,
IJIG(2), No. 4, October 2002, pp. 541-555. 0210
BibRef

Linnett, L.M., Carmichael, D.R., Clarke, S.J.,
Texture Classification Using a Spatial-Point Process Model,
VISP(142), No. 1, February 1995, pp. 1-6. BibRef 9502

Francos, J.M., Meiri, A.Z., and Porat, B.,
A Unified Texture Model Based on a 2-D Wold Like Decomposition,
TSP(41), August 1993, pp. 2665-2678. BibRef 9308

Francos, J.M., Meiri, A.Z.,
A unified structural-stochastic model for texture analysis and synthesis,
ICPR88(I: 41-45).
IEEE DOI Link 8811
BibRef

Francos, J.M., Narasimhan, A., Woods, J.W.,
Maximum likelihood parameter estimation of textures using a Wold-decomposition based model,
IP(4), No. 12, December 1995, pp. 1655-1666.
IEEE DOI Link 0402
BibRef

Sriram, R., Francos, J.M., Pearlman, W.A.,
Texture Coding Using a Wold Decomposition Model,
IP(5), No. 9, September 1996, pp. 1382-1386.
IEEE DOI Link BibRef 9609
Earlier: ICPR94(C:35-39).
IEEE DOI Link 9410
BibRef

Chen, J.L.[Jia-Lin], Kundu, A.,
Rotation and gray scale transform invariant texture identification using wavelet decomposition and hidden Markov model,
PAMI(16), No. 2, February 1994, pp. 208-214.
IEEE Abstract. IEEE Top Reference.
WWW Version. Wavelets. Markov Model. BibRef 9402

Chen, J.L., Kundu, A.,
Unsupervised Texture Segmentation Using Multichannel Decomposition and Hidden Markov-Models,
IP(4), No. 5, May 1995, pp. 603-619.
IEEE DOI Link BibRef 9505
Earlier:
Automatic Unsupervised Texture Segmentation Using Hidden Markov Model,
ICASSP93(V: 21-24). BibRef

Hall, T.E., Giannakis, G.B.,
Image Modeling Using Inverse Filtering Criteria with Application to Textures,
IP(5), No. 6, June 1996, pp. 938-949.
IEEE DOI Link 9607
BibRef
Earlier:
Image modeling using inverse filtering criteria with application to texture images,
ICIP94(III: 392-396).
IEEE DOI Link 9411
BibRef

Hall, T.E., Giannakis, G.B.,
Bispectral analysis and model validation of texture images,
IP(4), No. 7, July 1995, pp. 996-1009.
IEEE DOI Link 0402
BibRef

Manian, V.[Vidya], Vasquez, R.[Ramon],
Scaled and rotated texture classification using a class of basis functions,
PR(31), No. 12, December 1998, pp. 1937-1948.
WWW Version. BibRef 9812

Cristobal, G.[Gabriel], Hormigo, J.[Javier],
Texture segmentation through eigen-analysis of the Pseudo-Wigner distribution,
PRL(20), No. 3, March 1999, pp. 337-345. BibRef 9903

Chen, C.C.[Chien-Chang], Chen, C.C.[Chaur-Chin],
Filtering methods for texture discrimination,
PRL(20), No. 8, August 1999, pp. 783-790. BibRef 9908

Manian, V., Vasquez, R., Katiyar, P.,
Texture Classification Using Logical Operators,
IP(9), No. 10, October 2000, pp. 1693-1703.
IEEE DOI Link 0010
BibRef

Bisoi, A.K.[Ajay Kumar], Mishra, J.[Jibitesh],
On calculation of fractal dimension of images,
PRL(22), No. 6-7, May 2001, pp. 631-637.
HTML Version. 0105
BibRef

Bresch, M.[Manfred],
Optimizing filter banks for supervised texture recognition,
PR(35), No. 4, April 2002, pp. 783-790.
WWW Version. 0201
BibRef

Barsky, S.[Svetlana], Petrou, M.[Maria],
On the Reliability of Computing Wigner Texture Features,
JMIV(16), No. 2, March 2002, pp. 107-129.
WWW Version. 0202
BibRef

Zhu, S.C.[Song Chun], Liu, X.W.[Xiu-Wen],
Learning in Gibbsian Fields: How Accurate and How Fast Can It Be?,
PAMI(24), No. 7, July 2002, pp. 1001-1006.
IEEE Abstract. IEEE Top Reference. 0207
BibRef
Earlier: CVPR00(II: 2-9).
IEEE Abstract. IEEE Top Reference.
WWW Version. 0005
Identify 2 issues: efficience in liklihood functions and variance in approximating partitions functions. See also Minimax Entropy Principles and Its Application to Texture Modeling. BibRef

Huang, Y.[Yong], Chan, K.L.[Kap Luk], Zhang, Z.H.[Zhi-Hua],
Texture classification by multi-model feature integration using Bayesian networks,
PRL(24), No. 1-3, January 2003, pp. 393-401.
HTML Version. 0211
BibRef

Li, Y.[Yan], Peng, J.X.[Jia-Xiong],
Remote Sensing Texture Analysis Using Multi-Parameter and Multi-Scale Features,
PhEngRS(69), No. 4, April 2003, pp. 351-356. The new feature set, derived from fractional Brownian motion, is presented.
WWW Version. 0304
BibRef

Nunes, J.C., Bouaoune, Y., Delechelle, E., Niang, O., Bunel, P.,
Image analysis by bidimensional empirical mode decomposition,
IVC(21), No. 12, November 2003, pp. 1019-1026.
WWW Version. 0310
EMD (empirical mode decomposition) from Huang. Apply to texture extraction and image filtering. Multiple scales. BibRef

Nunes, J.C.[Jean Claude], Guyot, S., Deléchelle, E.[Eric],
Texture analysis based on local analysis of the Bidimensional Empirical Mode Decomposition,
MVA(16), No. 3, May 2005, pp. 177-188.
Springer DOI Link 0505
BibRef

Nunes, J.C.[Jean Claude], Niang, O.[Oumar], Bouaoune, Y.[Yasmina], Delechelle, E.[Eric], Bunel, P.[Philippe],
Bidimensional Empirical Mode Decomposition Modified for Texture Analysis,
SCIA03(171-177).
WWW Version. 0310
BibRef

Varma, M.[Manik], Zisserman, A.[Andrew],
A Statistical Approach to Texture Classification from Single Images,
IJCV(62), No. 1-2, April-May 2005, pp. 61-81.
WWW Version. 0411
BibRef
Earlier:
Texture classification: are filter banks necessary?,
CVPR03(II: 691-698).
IEEE Abstract. IEEE Top Reference. 0307
BibRef
And:
Classifying Images of Materials: Achieving Viewpoint and Illumination Independence,
ECCV02(III: 255 ff.).
HTML Version. 0205
Texture classification. Clustered filter responses. Compared to: Leung and Malik ( See also Representing and Recognizing the Visual Appearance of Materials using Three-dimensional Textons. ), Schmid ( See also Constructing Models for Content-Based Image Retrieval. ) and Cula and Dana ( See also 3D Texture Recognition Using Bidirectional Feature Histograms. ), BibRef

Varma, M.[Manik], Zisserman, A.[Andrew],
A Statistical Approach to Material Classification Using Image Patch Exemplars,
PAMI(31), No. 11, November 2009, pp. 2032-2047.
IEEE DOI Link 0910
BibRef

Varma, M.[Manik], Zisserman, A.[Andrew],
Unifying statistical texture classification frameworks,
IVC(22), No. 14, 1 December 2004, pp. 1175-1183.
WWW Version. 0412
BibRef

Chantler, M.J., Petrou, M., Penirsche, A., Schmidt, M., McGunnigle, G.,
Classifying Surface Texture while Simultaneously Estimating Illumination Direction,
IJCV(62), No. 1-2, April-May 2005, pp. 83-96.
WWW Version. 0411
BibRef

Penirsche, A., Chantler, M.J., Petrou, M.,
Illuminant Rotation Invariant Classification of 3D Surface Textures using Lissajous`s Ellipses,
Texture02(103-108). 0207
BibRef

Chantler, M.J., Schmidt, M., Petrou, M., McGunnigle, G.,
The Effect of Illuminant Rotation on Texture Filters: Lissajous's Ellipses,
ECCV02(III: 289 ff.).
HTML Version. 0205
BibRef

Gluckman, J.M.[Joshua M.],
Visually Distinct Patterns with Matching Subband Statistics,
PAMI(27), No. 2, February 2005, pp. 252-264.
IEEE Abstract. IEEE Top Reference. 0501
BibRef
Earlier:
On the use of marginal statistics of subband images,
ICCV03(448-455).
IEEE DOI Link 0311
BibRef
And:
Gradient field distributions for the registration of images,
ICIP03(II: 691-694).
IEEE Abstract. IEEE Top Reference. 0312
Analyze ability of various filters to distinguish different stimuli. When statistics are the same. BibRef

Kang, Y.[Yousun], Morooka, K.[Ken'ichi], Nagahashi, H.[Hiroshi],
Texture Classification Using Hierarchical Linear Discriminant Space,
IEICE(E88-D), No. 10, October 2005, pp. 2380-2388.
WWW Version. 0510
BibRef
Earlier:
Scale Invariant Texture Analysis Using Multi-scale Local Autocorrelation Features,
ScaleSpace05(363-373).
WWW Version. 0505
BibRef

Knutsson, H.[Hans], Andersson, M.[Mats],
Implications of invariance and uncertainty for local structure analysis filter sets,
SP:IC(20), No. 6, July 2005, pp. 569-581.
WWW Version. 0506
BibRef

Campisi, P.[Patrizio], Colonnese, S.[Stefania], Panci, G.[Gianpiero], Scarano, G.[Gaetano],
Reduced Complexity Rotation Invariant Texture Classification Using a Blind Deconvolution Approach,
PAMI(28), No. 1, January 2006, pp. 145-149.
IEEE DOI Link 0512
Features computed from one-dimensional slices extracted from the two-dimensional autocorrelation function (ACF) of the binary excitation allows representing the texture for rotation-invariant classification. BibRef

Bocher, P.K., McCloy, K.R.,
The Fundamentals of Average Local Variance: Part I: Detecting Regular Patterns,
IP(15), No. 2, February 2006, pp. 300-310.
IEEE DOI Link 0602
Mean and StDev of 3X3 window. BibRef

Bocher, P.K., McCloy, K.R.,
The Fundamentals of Average Local Variance: Part II: Sampling Simple Regular Patterns With Optical Imagery,
IP(15), No. 2, February 2006, pp. 311-318.
IEEE DOI Link 0602
BibRef

Petrou, M., Piroddi, R., Talebpour, A.,
Texture recognition from sparsely and irregularly sampled data,
CVIU(102), No. 1, April 2006, pp. 95-104.
WWW Version. Texture classification; Irregularly sampled data; Trace transform 0604
BibRef

Kadyrov, A., Talebpour, A., Petrou, M.,
Texture classification with thousands of features,
BMVC02(Poster Session). 0208
BibRef

Brox, T.[Thomas], Weickert, J.[Joachim],
A TV flow based local scale estimate and its application to texture discrimination,
JVCIR(17), No. 5, October 2006, pp. Journal of Visual Communication and Image RepresentationVolume 17, Issue 5, , October 2006, 1053-1073.
WWW Version. 0711
BibRef
Earlier:
A TV Flow Based Local Scale Measure for Texture Discrimination,
ECCV04(Vol II: 578-590).
WWW Version. 0405
See also Nonlinear Matrix Diffusion for Optic Flow Estimation. Scale; Texture; Nonlinear diffusion; Segmentation BibRef

Brox, T.[Thomas], Rousson, M.[Mikaël], Deriche, R.[Rachid], Weickert, J.[Joachim],
Unsupervised Segmentation Incorporating Colour, Texture, and Motion,
CAIP03(353-360).
WWW Version. 0311
BibRef
And: INRIARR-4760, Mars 2003.
HTML Version. 0306
BibRef

Rousson, M.[Mikaël], Brox, T.[Thomas], Deriche, R.[Rachid],
Active Unsupervised Texture Segmentation on a Diffusion Based Feature Space,
CVPR03(II: 699-704).
IEEE Abstract. IEEE Top Reference. 0307
BibRef
And: INRIARR-4695, Janvier 2003.
HTML Version. 0306
BibRef

Tzagkarakis, G., Beferull-Lozano, B., Tsakalides, P.,
Rotation-Invariant Texture Retrieval With Gaussianized Steerable Pyramids,
IP(15), No. 9, August 2006, pp. 2702-2718.
IEEE DOI Link 0608
BibRef

Tzagkarakis, G., Beferull-Lozano, B., Tsakalides, P.,
Rotation-Invariant Texture Retrieval via Signature Alignment Based on Steerable Sub-Gaussian Modeling,
IP(17), No. 7, July 2008, pp. 1212-1225.
IEEE DOI Link 0806
BibRef

Beferull-Lozano, B., Xie, H.[Hua], Orlegi, A.,
Rotation-invariant features based on steerable transforms with an application to distributed image classification,
ICIP03(III: 521-524).
IEEE Abstract. IEEE Top Reference. 0312
BibRef

Cheng, K.O., Law, N.F., Siu, W.C.,
Multiscale directional filter bank with applications to structured and random texture retrieval,
PR(40), No. 4, April 2007, pp. 1182-1194.
WWW Version. 0701
Texture characterization; Texture retrieval; Directional filter bank; Multiscale directional filter bank; Rotation-invariant features BibRef

Mellor, M.[Matthew], Hong, B.W.[Byung-Woo], Brady, M.[Michael],
Locally Rotation, Contrast, and Scale Invariant Descriptors for Texture Analysis,
PAMI(30), No. 1, January 2008, pp. 52-61.
IEEE DOI Link 0711
New family of filters. BibRef

Wang, M.S.[Ming-Shi], Knoesen, A.[André],
Rotation- and scale-invariant texture features based on spectral moment invariants,
JOSA-A(24), No. 9, September 2007, pp. 2550-2557.
WWW Version. 0801
BibRef

Salzenstein, F.[Fabien], Boudraa, A.O.[Abdel-Ouahab], Cexus, J.C.[Jean-Christophe],
Generalized higher-order nonlinear energy operators,
JOSA-A(24), No. 12, December 2007, pp. 3717-3727.
WWW Version. 0801
BibRef

Zhou, H.[Hui], Wang, R.S.[Run-Sheng], Wang, C.[Cheng],
A novel extended local-binary-pattern operator for texture analysis,
IS(178), No. 22, November, 2008, pp. 4314-4325.
Elsevier DOI Link 0905
BibRef

Xu, G.L.[Guan-Lei], Wang, X.T.[Xiao-Tong], Xu, X.G.[Xiao-Gang],
Improved bi-dimensional EMD and Hilbert spectrum for the analysis of textures,
PR(42), No. 5, May 2009, pp. 718-734.
Elsevier DOI Link
WWW Version. 0902
Empirical mode decomposition (EMD); Intrinsic mode functions (IMF); Quaternion Hilbert transform; Pseudo extrema BibRef


Maurel, P.[Pierre], Aujol, J.F.[Jean-François], Peyré, G.[Gabriel],
Locally Parallel Textures Modeling with Adapted Hilbert Spaces,
EMMCVPR09(429-442).
Springer DOI Link 0908
BibRef

Guo, Z.H.[Zhen-Hua], Zhang, L.[Lei], Zhang, D.[David],
Rotation Invariant Texture Classification Using Binary Filter Response Pattern (BFRP),
CAIP09(1130-1137).
Springer DOI Link 0909
BibRef

Kondra, S.[Shripad], Torre, V.[Vincent],
Texture Classification Using Three Circular Filters,
ICCVGIP08(429-434).
IEEE DOI Link 0812
BibRef

Bors, A.G.[Adrian G.], Nasios, N.[Nikolaos],
Kernel bandwidth estimation in methods based on probability density function modelling,
ICPR08(1-4).
IEEE DOI Link 0812
BibRef

Ray, N.[Nilanjan], Saha, B.[Baidyanath], Acton, S.T.[Scott T.],
Oil sand image segmentation using the inclusion filter,
ICIP08(2188-2191).
IEEE DOI Link 0810
BibRef

Ray, N., Acton, S.T.,
Self-dual inclusion filters for grayscale imagery,
ICIP03(I: 321-324).
IEEE Abstract. IEEE Top Reference. 0312
BibRef

Daurat, A.[Alain], Tajine, M.[Mohamed], Zouaoui, M.[Mahdi],
About the Frequencies of Some Patterns in Digital Planes: Application to Area Estimators,
DGCI08(xx-yy).
Springer DOI Link 0804
BibRef

Quiroga, J.[Julian], Restrepo, A.[Alfredo], Wedefort, L.[Lina], Velasco, M.[Margarita],
On the 2D Teager-Kaiser Operator,
ICIP07(V: 269-272).
IEEE DOI Link 0709
TK: a discrete, nonlinear moving window filter to compute energy. BibRef

Muñiz, R.[Rubén], Corrales, J.A.[José Antonio],
An Approach for Extracting Illumination-Independent Texture Features,
ICIAR07(93-104).
Springer DOI Link 0708
BibRef

Muñiz, R.[Rubén], Corrales, J.A.[José Antonio], Rico-Secades, M.[Manuel],
Use of band ratioing for building illumination independent texture classification systems,
ICPR08(1-4).
IEEE DOI Link 0812
BibRef

Chamorro-Martínez, J., Martínez-Jiménez, P.,
Texture Measuring by Means of Perceptually-Based Fineness Functions,
IbPRIA09(265-272).
Springer DOI Link 0906
BibRef

Chamorro-Martínez, J., Galán-Perales, E., Prados-Suárez, B., Soto-Hidalgo, J.M.,
Perceptually-Based Functions for Coarseness Textural Feature Representation,
IbPRIA07(I: 579-586).
Springer DOI Link 0706
BibRef

Vidal-Naquet, M.[Michel], Tanifuji, M.[Manabu],
The effective resolution of correlation filters applied to natural scenes,
BP07(1-6).
IEEE DOI Link 0706
BibRef

Janney, P.[Pranam], Yu, Z.H.[Zheng-Hua],
Invariant Features of Local Textures: A rotation invariant local texture descriptor,
BP07(1-7).
IEEE DOI Link 0706
BibRef

Hussain, A., Rajpoot, N., Rajpoot, K.,
Texture Classification with Ants,
ICIP06(3013-3016). 0610

IEEE DOI Link BibRef

Verzakov, S., Paclík, P., Duin, R.P.W.,
The Tangent Kernel Approach to Illumination-Robust Texture Classification,
SCIA05(1009-1016).
Springer DOI Link 0506
BibRef

Silva Santos, C., Kogler, J.E., Del Moral Hernandez, E.,
Using Independent Subspace Analysis for Selecting Filters Used in Texture Processing,
ICIP05(I: 465-468).
IEEE DOI Link 0512
BibRef

Van de Wouwer, G., Weyn, B., Van Dyck, D.,
Multiscale, asymmetry signatures for texture analysis,
ICIP04(III: 1517-1520).
IEEE DOI Link 0505
BibRef

Sabri, M., Alirezaie, J.,
Optimized space frequency kernel for texture classification,
ICIP04(III: 1521-1524).
IEEE DOI Link 0505
BibRef

Costantini, R., Menegaz, G., Susstrunk, S.,
A measure for spatial dependence in natural stochastic textures,
ICIP04(III: 1525-1528).
IEEE DOI Link 0505
BibRef

Koroutchev, K.[Kostadin], Dorronsoro, J.R.[José R.],
Factorization of Natural 4X4 Patch Distributions,
SMVP04(165-174).
WWW Version. 0505
BibRef

Cuenca, S.A.,
Texture analysis based on local semicovers,
CIAP03(588-593).
IEEE Abstract. IEEE Top Reference. 0310
BibRef

Liu, X.W.[Xiu-Wen], Cheng, L.[Lei],
Independent filters for texture classification,
ICIP02(III: 113-116).
IEEE Abstract. IEEE Top Reference. 0210
BibRef

Schael, M.,
Invariant Texture Classification Using Group Averaging with Relational Kernel Functions,
Texture02(129-134). 0207
BibRef

Clark, A.A.,
Texture Deconvolution for the Fourier-Based Analysis of Non-Rectangular Regions,
BMVC99(Posters/Demos).
PDF Version. BibRef 9900

Heikkinen, K., Vuorimaa, P.,
Computation of two texture features in hardware,
CIAP99(125-129).
IEEE DOI Link 9909
BibRef

Huet, F., Mattioli, J.,
A textural analysis by mathematical morphology transformations: structural opening and top-hat,
ICIP96(III: 49-52).
IEEE DOI Link 9610
BibRef

Jackson, S., Ahuja, N.,
Elliptical Gaussian Filters,
ICPR96(II: 775-779).
IEEE DOI Link 9608
(Intel Corporation, USA) BibRef

Ma, W.Y., Manjunath, B.S.,
A Comparison of Wavelet Features for Texture Annotation,
ICIP95(II: 256-259).
IEEE DOI Link 9510

PDF Version. BibRef

Greenhill, D., Davies, E.R.,
Texture Analysis Using Neural Networks and Mode Filters,
BMVC93(xx-yy).
PDF Version. 9309
BibRef

Lonnestad, T.,
A new set of texture features based on the Haar transform,
ICPR92(III:676-679).
IEEE DOI Link 9208
BibRef

Lee, H.Y.,
Extraction of Textured Regions in Aerial Imagery,
DARPA83(298-303). BibRef 8300

Laws, K.I.[Kenneth I.],
Rapid Texture Identification,
SPIEConf. Image Processing for Missile Guidance, 1980, pp. 376-380. BibRef 8000

Laws, K.I.[Kenneth I.],
Texture Energy Measures,
DARPAN79(47-51). BibRef 7900 USC Computer VisionIntroduces the texture measures developed in his thesis. See also Textured Image Segmentation. BibRef

Chapter on 2-D Feature Analysis, Extraction and Representations, Shape, Skeletons, Texture continues in
Wavelets, Gabor Filters for Texture .


Last update:Nov 16, 2009 at 19:35:14