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Author	Fahad Shahbaz Khan; Joost Van de Weijer; Maria Vanrell
Title	Top-Down Color Attention for Object Recognition			Type	Conference Article
Year	2009	Publication	12th International Conference on Computer Vision	Abbreviated Journal
Volume		Issue		Pages	979 - 986
Keywords
Abstract	Generally the bag-of-words based image representation follows a bottom-up paradigm. The subsequent stages of the process: feature detection, feature description, vocabulary construction and image representation are performed independent of the intentioned object classes to be detected. In such a framework, combining multiple cues such as shape and color often provides below-expected results. This paper presents a novel method for recognizing object categories when using multiple cues by separating the shape and color cue. Color is used to guide attention by means of a top-down category-specific attention map. The color attention map is then further deployed to modulate the shape features by taking more features from regions within an image that are likely to contain an object instance. This procedure leads to a category-specific image histogram representation for each category. Furthermore, we argue that the method combines the advantages of both early and late fusion. We compare our approach with existing methods that combine color and shape cues on three data sets containing varied importance of both cues, namely, Soccer ( color predominance), Flower (color and shape parity), and PASCAL VOC Challenge 2007 (shape predominance). The experiments clearly demonstrate that in all three data sets our proposed framework significantly outperforms the state-of-the-art methods for combining color and shape information.
Address	Kyoto, Japan
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1550-5499	ISBN	978-1-4244-4420-5	Medium
Area		Expedition		Conference	ICCV
Notes	CIC			Approved	no
Call Number	CAT @ cat @ SWV2009			Serial	1196
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Author	Jaime Moreno; Xavier Otazu; Maria Vanrell
Title	Local Perceptual Weighting in JPEG2000 for Color Images			Type	Conference Article
Year	2010	Publication	5th European Conference on Colour in Graphics, Imaging and Vision and 12th International Symposium on Multispectral Colour Science	Abbreviated Journal
Volume		Issue		Pages	255–260
Keywords
Abstract	The aim of this work is to explain how to apply perceptual concepts to define a perceptual pre-quantizer and to improve JPEG2000 compressor. The approach consists in quantizing wavelet transform coefficients using some of the human visual system behavior properties. Noise is fatal to image compression performance, because it can be both annoying for the observer and consumes excessive bandwidth when the imagery is transmitted. Perceptual pre-quantization reduces unperceivable details and thus improve both visual impression and transmission properties. The comparison between JPEG2000 without and with perceptual pre-quantization shows that the latter is not favorable in PSNR, but the recovered image is more compressed at the same or even better visual quality measured with a weighted PSNR. Perceptual criteria were taken from the CIWaM (Chromatic Induction Wavelet Model).
Address	Joensuu, Finland
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN	9781617388897	Medium
Area		Expedition		Conference	CGIV/MCS
Notes	CIC			Approved	no
Call Number	CAT @ cat @ MOV2010a			Serial	1307
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Author	Jaime Moreno; Xavier Otazu; Maria Vanrell
Title	Contribution of CIWaM in JPEG2000 Quantization for Color Images			Type	Conference Article
Year	2010	Publication	Proceedings of The CREATE 2010 Conference	Abbreviated Journal
Volume		Issue		Pages	132–136
Keywords
Abstract	The aim of this work is to explain how to apply perceptual concepts to define a perceptual pre-quantizer and to improve JPEG2000 compressor. The approach consists in quantizing wavelet transform coefficients using some of the human visual system behavior properties. Noise is fatal to image compression performance, because it can be both annoying for the observer and consumes excessive bandwidth when the imagery is transmitted. Perceptual pre-quantization reduces unperceivable details and thus improve both visual impression and transmission properties. The comparison between JPEG2000 without and with perceptual pre-quantization shows that the latter is not favorable in PSNR, but the recovered image is more compressed at the same or even better visual quality measured with a weighted PSNR. Perceptual criteria were taken from the CIWaM(ChromaticInductionWaveletModel).
Address	Gjovik (Norway)
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	CREATE
Notes	CIC			Approved	no
Call Number	CAT @ cat @ MOV2010b			Serial	1308
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Author	C. Alejandro Parraga; Ramon Baldrich; Maria Vanrell
Title	Accurate Mapping of Natural Scenes Radiance to Cone Activation Space: A New Image Dataset			Type	Conference Article
Year	2010	Publication	5th European Conference on Colour in Graphics, Imaging and Vision and 12th International Symposium on Multispectral Colour Science	Abbreviated Journal
Volume		Issue		Pages	50–57
Keywords
Abstract	The characterization of trichromatic cameras is usually done in terms of a device-independent color space, such as the CIE 1931 XYZ space. This is indeed convenient since it allows the testing of results against colorimetric measures. We have characterized our camera to represent human cone activation by mapping the camera sensor's (RGB) responses to human (LMS) through a polynomial transformation, which can be “customized” according to the types of scenes we want to represent. Here we present a method to test the accuracy of the camera measures and a study on how the choice of training reflectances for the polynomial may alter the results.
Address	Joensuu, Finland
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN	9781617388897	Medium
Area		Expedition		Conference	CGIV/MCS
Notes	CIC			Approved	no
Call Number	CAT @ cat @ PBV2010a			Serial	1322
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Author	Javier Vazquez; G. D. Finlayson; Maria Vanrell
Title	A compact singularity function to predict WCS data and unique hues			Type	Conference Article
Year	2010	Publication	5th European Conference on Colour in Graphics, Imaging and Vision and 12th International Symposium on Multispectral Colour Science	Abbreviated Journal
Volume		Issue		Pages	33–38
Keywords
Abstract	Understanding how colour is used by the human vision system is a widely studied research field. The field, though quite advanced, still faces important unanswered questions. One of them is the explanation of the unique hues and the assignment of color names. This problem addresses the fact of different perceptual status for different colors. Recently, Philipona and O'Regan have proposed a biological model that allows to extract the reflection properties of any surface independently of the lighting conditions. These invariant properties are the basis to compute a singularity index that predicts the asymmetries presented in unique hues and basic color categories psychophysical data, therefore is giving a further step in their explanation. In this paper we build on their formulation and propose a new singularity index. This new formulation equally accounts for the location of the 4 peaks of the World colour survey and has two main advantages. First, it is a simple elegant numerical measure (the Philipona measurement is a rather cumbersome formula). Second, we develop a colour-based explanation for the measure.
Address	Joensuu, Finland
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN	9781617388897	Medium
Area		Expedition		Conference	CGIV/MCS
Notes	CIC			Approved	no
Call Number	CAT @ cat @ VFV2010			Serial	1324
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Author	Susana Alvarez; Anna Salvatella; Maria Vanrell; Xavier Otazu
Title	3D Texton Spaces for color-texture retrieval			Type	Conference Article
Year	2010	Publication	7th International Conference on Image Analysis and Recognition	Abbreviated Journal
Volume	6111	Issue		Pages	354–363
Keywords
Abstract	Color and texture are visual cues of different nature, their integration in an useful visual descriptor is not an easy problem. One way to combine both features is to compute spatial texture descriptors independently on each color channel. Another way is to do the integration at the descriptor level. In this case the problem of normalizing both cues arises. In this paper we solve the latest problem by fusing color and texture through distances in texton spaces. Textons are the attributes of image blobs and they are responsible for texture discrimination as defined in Julesz’s Texton theory. We describe them in two low-dimensional and uniform spaces, namely, shape and color. The dissimilarity between color texture images is computed by combining the distances in these two spaces. Following this approach, we propose our TCD descriptor which outperforms current state of art methods in the two different approaches mentioned above, early combination with LBP and late combination with MPEG-7. This is done on an image retrieval experiment over a highly diverse texture dataset from Corel.
Address
Corporate Author				Thesis
Publisher	Springer Berlin Heidelberg	Place of Publication		Editor	A.C. Campilho and M.S. Kamel
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title	LNCS
Series Volume		Series Issue		Edition
ISSN	0302-9743	ISBN	978-3-642-13771-6	Medium
Area		Expedition		Conference	ICIAR
Notes	CIC			Approved	no
Call Number	CAT @ cat @ ASV2010a			Serial	1325
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Author	C. Alejandro Parraga; Robert Benavente; Maria Vanrell
Title	Towards a general model of colour categorization which considers context			Type	Journal Article
Year	2010	Publication	Perception. ECVP Abstract Supplement	Abbreviated Journal	PER
Volume	39	Issue		Pages	86
Keywords
Abstract	In two previous experiments [Parraga et al, 2009 J. of Im. Sci. and Tech 53(3) 031106; Benavente et al,2009 Perception 38 ECVP Supplement, 36] the boundaries of basic colour categories were measured. In the ﬁrst experiment, samples were presented in isolation (ie on a dark background) and boundaries were measured using a yes/no paradigm. In the second, subjects adjusted the chromaticity of a sample presented on a random Mondrian background to ﬁnd the boundary between pairs of adjacent colours. Results from these experiments showed signiﬁcant dierences but it was not possible to conclude whether this discrepancy was due to the absence/presence of a colourful background or to the dierences in the paradigms used. In this work, we settle this question by repeating the ﬁrst experiment (ie samples presented on a dark background) using the second paradigm. A comparison of results shows that although boundary locations are very similar, boundaries measured in context are signiﬁcantly dierent(more diuse) than those measured in isolation (conﬁrmed by a Student’s t-test analysis on the subject’s answers statistical distributions). In addition, we completed the mapping of colour name space by measuring the boundaries between chromatic colours and the achromatic centre. With these results we completed our parametric fuzzy-sets model of colour naming space.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference
Notes	CIC			Approved	no
Call Number	CAT @ cat @ PBV2010b			Serial	1326
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Author	Robert Benavente; C. Alejandro Parraga; Maria Vanrell
Title	La influencia del contexto en la definicion de las fronteras entre las categorias cromaticas			Type	Conference Article
Year	2010	Publication	9th Congreso Nacional del Color	Abbreviated Journal
Volume		Issue		Pages	92–95
Keywords	Categorización del color; Apariencia del color; Influencia del contexto; Patrones de Mondrian; Modelos paramétricos
Abstract	En este artículo presentamos los resultados de un experimento de categorización de color en el que las muestras se presentaron sobre un fondo multicolor (Mondrian) para simular los efectos del contexto. Los resultados se comparan con los de un experimento previo que, utilizando un paradigma diferente, determinó las fronteras sin tener en cuenta el contexto. El análisis de los resultados muestra que las fronteras obtenidas con el experimento en contexto presentan menos confusión que las obtenidas en el experimento sin contexto.
Address	Alicante (Spain)
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN	978-84-9717-144-1	Medium
Area		Expedition		Conference	CNC
Notes	CIC			Approved	no
Call Number	CAT @ cat @ BPV2010			Serial	1327
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Author	Javier Vazquez; Maria Vanrell; Robert Benavente
Title	Color names as a constraint for Computer Vision problems			Type	Conference Article
Year	2010	Publication	Proceedings of The CREATE 2010 Conference	Abbreviated Journal
Volume		Issue		Pages	324–328
Keywords
Abstract	Computer Vision Problems are usually ill-posed. Constraining de gamut of possible solutions is then a necessary step. Many constrains for different problems have been developed during years. In this paper, we present a different way of constraining some of these problems: the use of color names. In particular, we will focus on segmentation, representation ans constancy.
Address	Gjovik (Norway)
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	CREATE
Notes	CIC			Approved	no
Call Number	CAT @ cat @ VVB2010			Serial	1328
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Author	Fahad Shahbaz Khan; Joost Van de Weijer; Maria Vanrell
Title	Who Painted this Painting?			Type	Conference Article
Year	2010	Publication	Proceedings of The CREATE 2010 Conference	Abbreviated Journal
Volume		Issue		Pages	329–333
Keywords
Abstract
Address	Gjovik (Norway)
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	CREATE
Notes	CIC			Approved	no
Call Number	CAT @ cat @ KWV2010			Serial	1329
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Author	Olivier Penacchio; C. Alejandro Parraga; Maria Vanrell
Title	Natural Scene Statistics account for Human Cones Ratios			Type	Journal Article
Year	2010	Publication	Perception. ECVP Abstract Supplement	Abbreviated Journal	PER
Volume	39	Issue		Pages	101
Keywords
Abstract	In two previous experiments [Parraga et al, 2009 J. of Im. Sci. and Tech 53(3) 031106; Benavente et al,2009 Perception 38 ECVP Supplement, 36] the boundaries of basic colour categories were measured. In the ﬁrst experiment, samples were presented in isolation (ie on a dark background) and boundaries were measured using a yes/no paradigm. In the second, subjects adjusted the chromaticity of a sample presented on a random Mondrian background to ﬁnd the boundary between pairs of adjacent colours. Results from these experiments showed signiﬁcant dierences but it was not possible to conclude whether this discrepancy was due to the absence/presence of a colourful background or to the dierences in the paradigms used. In this work, we settle this question by repeating the ﬁrst experiment (ie samples presented on a dark background) using the second paradigm. A comparison of results shows that although boundary locations are very similar, boundaries measured in context are signiﬁcantly dierent(more diuse) than those measured in isolation (conﬁrmed by a Student’s t-test analysis on the subject’s answers statistical distributions). In addition, we completed the mapping of colour name space by measuring the boundaries between chromatic colours and the achromatic centre. With these results we completed our parametric fuzzy-sets model of colour naming space.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference
Notes	CIC			Approved	no
Call Number	CAT @ cat @ PPV2010			Serial	1357
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Author	Susana Alvarez; Anna Salvatella; Maria Vanrell; Xavier Otazu
Title	Perceptual color texture codebooks for retrieving in highly diverse texture datasets			Type	Conference Article
Year	2010	Publication	20th International Conference on Pattern Recognition	Abbreviated Journal
Volume		Issue		Pages	866–869
Keywords
Abstract	Color and texture are visual cues of different nature, their integration in a useful visual descriptor is not an obvious step. One way to combine both features is to compute texture descriptors independently on each color channel. A second way is integrate the features at a descriptor level, in this case arises the problem of normalizing both cues. A significant progress in the last years in object recognition has provided the bag-of-words framework that again deals with the problem of feature combination through the definition of vocabularies of visual words. Inspired in this framework, here we present perceptual textons that will allow to fuse color and texture at the level of p-blobs, which is our feature detection step. Feature representation is based on two uniform spaces representing the attributes of the p-blobs. The low-dimensionality of these text on spaces will allow to bypass the usual problems of previous approaches. Firstly, no need for normalization between cues; and secondly, vocabularies are directly obtained from the perceptual properties of text on spaces without any learning step. Our proposal improve current state-of-art of color-texture descriptors in an image retrieval experiment over a highly diverse texture dataset from Corel.
Address	Istanbul (Turkey)
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1051-4651	ISBN	978-1-4244-7542-1	Medium
Area		Expedition		Conference	ICPR
Notes	CIC			Approved	no
Call Number	CAT @ cat @ ASV2010b			Serial	1426
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Author	Xavier Otazu; C. Alejandro Parraga; Maria Vanrell
Title	Towards a unified chromatic inducction model			Type	Journal Article
Year	2010	Publication	Journal of Vision	Abbreviated Journal	VSS
Volume	10	Issue	12:5	Pages	1-24
Keywords	Visual system; Color induction; Wavelet transform
Abstract	In a previous work (X. Otazu, M. Vanrell, & C. A. Párraga, 2008b), we showed how several brightness induction effects can be predicted using a simple multiresolution wavelet model (BIWaM). Here we present a new model for chromatic induction processes (termed Chromatic Induction Wavelet Model or CIWaM), which is also implemented on a multiresolution framework and based on similar assumptions related to the spatial frequency and the contrast surround energy of the stimulus. The CIWaM can be interpreted as a very simple extension of the BIWaM to the chromatic channels, which in our case are defined in the MacLeod-Boynton (lsY) color space. This new model allows us to unify both chromatic assimilation and chromatic contrast effects in a single mathematical formulation. The predictions of the CIWaM were tested by means of several color and brightness induction experiments, which showed an acceptable agreement between model predictions and psychophysical data.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference
Notes	CIC			Approved	no
Call Number	CAT @ cat @ OPV2010			Serial	1450
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Author	Eduard Vazquez; Ramon Baldrich; Joost Van de Weijer; Maria Vanrell
Title	Describing Reflectances for Colour Segmentation Robust to Shadows, Highlights and Textures			Type	Journal Article
Year	2011	Publication	IEEE Transactions on Pattern Analysis and Machine Intelligence	Abbreviated Journal	TPAMI
Volume	33	Issue	5	Pages	917-930
Keywords
Abstract	The segmentation of a single material reflectance is a challenging problem due to the considerable variation in image measurements caused by the geometry of the object, shadows, and specularities. The combination of these effects has been modeled by the dichromatic reflection model. However, the application of the model to real-world images is limited due to unknown acquisition parameters and compression artifacts. In this paper, we present a robust model for the shape of a single material reflectance in histogram space. The method is based on a multilocal creaseness analysis of the histogram which results in a set of ridges representing the material reflectances. The segmentation method derived from these ridges is robust to both shadow, shading and specularities, and texture in real-world images. We further complete the method by incorporating prior knowledge from image statistics, and incorporate spatial coherence by using multiscale color contrast information. Results obtained show that our method clearly outperforms state-of-the-art segmentation methods on a widely used segmentation benchmark, having as a main characteristic its excellent performance in the presence of shadows and highlights at low computational cost.
Address	Los Alamitos; CA; USA;
Corporate Author				Thesis
Publisher	IEEE Computer Society	Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0162-8828	ISBN		Medium
Area		Expedition		Conference
Notes	CIC			Approved	no
Call Number	Admin @ si @ VBW2011			Serial	1715
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