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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Associating Colors to Emotional Concepts Extracted from Unstructured Texts</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Alberto Fernandez-Isabel</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Antonio F. G. Sevilla</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Alberto D az</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>NIL??</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Facultad de Informatica</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Madrid</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Spain afernandezisabel@ucm.es</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>afgs@ucm.es</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>albertodiaz@fdi.ucm.es</string-name>
        </contrib>
      </contrib-group>
      <kwd-group>
        <kwd>Natural language processing</kwd>
        <kwd>concept extraction</kwd>
        <kwd>abtract painting</kwd>
        <kwd>painter software</kwd>
        <kwd>semantic expression</kwd>
        <kwd>information retrieval</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>
        Copyright © 2016 for this paper by its authors. Copying permitted for private and academic purposes.
[
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] or distributed over the canvas randomly focusing on more generic abstract
painting processes [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ].
      </p>
      <p>
        Our proposal introduces the framework called CALyPSe (Conceptual
Abstract and Lyric Painting System) that is able to produce color palettes and
abstract paintings. The resulting pictures are generated from concepts related to
human feelings and emotions extracted from an input text. These are checked to
prede ned notions which are associated to a speci c color following the
relationships introduced in [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. The nal painting is built according to the dimensions of
the canvas and the color palette. This latter is generated considering the amount
of concepts identi ed and harmony color techniques [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. The organization of
pixels which compose the complete image follows a randomly distribution.
      </p>
      <p>
        The framework is composed by three di erent modules: concept extraction,
concept storage and painting generation. They count with their respective
manager which is responsible for connecting their internal tools and make them work
together. The rst module takes as input an unstructured text and extract the
concepts from it through Freeling [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ] and a semantic analyzer. In the second one
its manager stores these concepts that can be related to a speci c color in the
knowledge database. These relationships might be produced directly or through
synonyms. These latter are obtained using WordNet [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. Optionally, the
concepts gathered can be searched on Wikipedia, processing the rst paragraph of
their de nition if the web page exists. The third module is oriented to develop
the nal painting according to the information collected.
      </p>
      <p>A case study illustrates an experiment where abstract paintings based on
obtaining concepts from texts are generated. Two di erent texts gathered from
Wikipedia related to human emotions and feelings are selected. The rst one
describes love while the second talks about death. The tool generates two abstract
paintings according to them. These are analyzed both qualitative and
quantitative, focusing on two speci c points: the colors used to produce the pictures with
each one of the selected texts, and the amount of di erent concepts identi ed
and their proportion.</p>
      <p>The rest of the paper is organized as follows. Section 2 compares this proposal
with related work. The CALyPSe framework is introduced in Section 3 delving
into their modules and managers that are responsible for them. The case study
in Section 4 shows the application of the approach. Finally, Section 5 discusses
some conclusions and future work which concern to the issue.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Related work</title>
      <p>The framework presented in this approach links natural language processing and
information retrieval with the expression of emotions through abstract painting.
This section discusses the existing tools and its foundations comparing them
with their alternatives.</p>
      <p>
        The framework accomplishes the extraction of concepts from an input text
according to its dependency analysis through Freeling [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ]. This tool automatizes
the required steps using di erent layers of linguistic analysis. A similar
alternative consists of the Stanford parser [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] which is also able to generate their own
type of speci c relations and dependencies applying stochastic analysis. Both
tools are designed to ease their integration into a more complex pipeline.
      </p>
      <p>
        The semantic information retrieval and lexical support for obtaining
synonyms is provided by WordNet [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. It is the standard lexical knowledge base
where certain related items can be collected (e.g., verbs, nouns or adjectives).
      </p>
      <p>Regarding the painting artist frameworks, there are multiple approaches but
three main perspectives are related to our proposal: frameworks that mimic
existing human artists styles, creative painting based on feelings and emotions,
and collage generation.</p>
      <p>
        Mimic human styles is a complex issue due to each painter develops a
personal style. Nevertheless there are proposals that try to evoke some notions or
standards related to a speci c painter [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] or painting techniques [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. Others more
generic are focused on generating images simulating their own style as painters
[
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] or rendering images to simulate certain strokes techniques in paintings [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
      </p>
      <p>
        Creative painting is oriented to simulate human emotions through an
intelligent software that follows some rules or background [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. One of the famous
frameworks in this eld is The Painting Fool [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. It is based on creativity
associated to the elaboration of pictures through non-photorealistic rendering.
      </p>
      <p>
        Collage generation consists of producing a picture integrating di erent images
that could have sense together. The information to represent can be obtained
from di erent sources. One of the most common is the processing of unstructured
texts [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. The di erent images which are added to the painting are usually
extracted from the web.
      </p>
      <p>
        There also are frameworks similar to CALyPSe. For instance, [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ] is able to
produce images according to a set of adjectives that describe the input.
      </p>
      <p>
        CALyPSe framework generates its paintings taking as a reference the abstract
art, while it identi es the concepts related to thoughts and emotions from an
input text associating them to colors. The conception process of these paintings
uses a random algorithm (instead of positioning or organizing the pixels) in order
to simulate modern art guidelines [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ].
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>Associating colors to emotional concepts</title>
      <p>This approach presents CALyPSe which is a framework oriented to produce color
palettes and abstract pictures that express the emotions and feelings included
in an unstructured text. To accomplish it, the tool has a set of modules in
order to classify the di erent tasks to perform (e.g., concept extraction or color
comparisons) until the picture is generated.</p>
      <p>
        It has an structure based on three main modules (see Fig. 1): concept
extraction, concept storage and painting generation. The rst processes the input texts
and organizes the concepts captured from them by sentences. The second has the
storage structures and implements the connection to WordNet database[
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. The
third is in charge of collecting the knowledge stored and producing the resulting
abstract picture.
      </p>
      <p>Section 3.1 introduces the concept extraction module, while the concept
storage is described in Section 3.2. The issues related to the painting generation
module are addressed in Section 3.3.
3.1</p>
      <sec id="sec-3-1">
        <title>Concept extraction</title>
        <p>
          This module is in charge of processing the current input text identifying its
concepts. To achieve this operation it uses two items: Freeling [
          <xref ref-type="bibr" rid="ref18">18</xref>
          ] and a semantic
analyzer. The extraction manager synchronizes both in order to generate the
appropriate result (see Fig. 1).
        </p>
        <p>
          Freeling [
          <xref ref-type="bibr" rid="ref18">18</xref>
          ] evaluates the input text achieving a dependency analysis. This
allows producing its syntax structure and the identi cation of the di erent types
of words (e.g., nouns, verbs or adjectives). This structure is captured by the
extraction manager.
        </p>
        <p>The semantic analyzer receives as input the syntax structure stored by the
extraction manager. It examines the di erent elements and extracts the lemmas
of the concepts discarding the pronouns and the articles (they are not
appropriated to be compared to the concepts related to colors). The manager is also in
charge of producing the nal result of the module, organizing these lemmas by
sentence following the order of precedence provided by the text.</p>
        <p>
          Note that the module obtains the input texts through three di erent ways
according to the features provided by the framework. It is able to analyze
unstructured text, read les and collect their texts, or process a web page selecting
only its paragraphs. This latter uses techniques related to web scraping [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ] that
allow extracting only the raw text.
3.2
        </p>
      </sec>
      <sec id="sec-3-2">
        <title>Concept storage</title>
        <p>
          It is the module where the information collected from the input texts is processed
and stored. It is composed by a knowledge database, a WordNet [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ] database
connection and the concept manager that control the interactions among these
elements (see Fig. 1).
        </p>
        <p>
          The knowledge database presents two internal structures: color structure and
concept structure. The rst one stores 179 relations among concepts (i.e., keys)
and colors collected from the literature that concerns to psychology of colors [
          <xref ref-type="bibr" rid="ref12">12</xref>
          ]
(see Table 1). The second contains a set of head concepts which are the keys
with an associated color in the rst structure. Each one of the positions of the
concept structure stores how many times the head element has been related to
the concepts from the input text and a list of items. This list might contain the
same concept of the head element or associated concepts. The list supports the
simulation of associative learning based on words in sentences [
          <xref ref-type="bibr" rid="ref19">19</xref>
          ]. In order to
achieve it, when a notion does not match with any head element or item of lists
but others of the same sentence does, the unmatched concept is stored in the
list of these latter (see Table 2). This establishes a semantic relationship among
the concept and the rest of notions that could be identi ed in its same sentence.
        </p>
        <p>
          WordNet [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ] is used by the concept manager to nd synonyms. It allows
associating more notions from the text with the head elements of the concept
structure.
        </p>
        <p>The module presents an optional set of items related to Wikipedia in order
to increment the color enrichment of the nal painting. It is able to extend each
one of the concepts extracted from the text in order to nd a description of it in
its related Wikipedia web page. In the case the page exists, it is scraped and the
rst paragraph is gathered. This text is sent to the concept extraction module
where its concepts are obtained. These are stored in the concept structure if
they produce matches with its head elements. In order to avoid in nite cycles
the concepts selected from this part has an special identi cation.
3.3</p>
      </sec>
      <sec id="sec-3-3">
        <title>Painting generation</title>
        <p>This module produces the color palette and the resulting picture. It is
accomplished using both structures contained in the knowledge database (i.e., concept
structure and color structure).</p>
        <p>
          The painting manager is responsible for achieving the painting generation. It
applies a set of rules related to color harmony [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ] in order to generate the color
palette. These rules are implemented through a basic lter. It allows discarding
mixtures among combinations of similar colors (where the most important
prevail) that do not produce an appropriate contrast to human eye (e.g., red color
does not match to pink color).
        </p>
        <p>Then, the painting manager produces the nal composition obtaining the
number of elements of the positions of the concept structure that are related to
the ltered colors. This is obtained comparing the head elements to the keys
of the color structure. Thus, the painting is built randomly according to the
proportion between the number of elements and the dimension of the canvas.
4</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Case Study</title>
      <p>The case study illustrates how the tool produces two di erent palettes and
pictures based on them from unstructured texts selected from Wikipedia. These
texts introduce information about two speci c human feelings or thoughts: love
and death. The images obtained from them are compared in a visual way and
the amount of concepts detected during the process are analyzed. The Wikipedia
optional feature provided by the framework (see Section 3.2) is not considered
in this case.</p>
      <p>
        The framework starts reseting the concept structure of the knowledge database.
Then the extraction manager scraps the corresponding web pages obtaining the
input texts. These texts are provided to Freeling [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ] in order to generate their
dependency analysis. This output is processed by the semantic analyzer which
is in charge of obtaining the lemmas of the identi ed concepts.
      </p>
      <p>
        In the next step the concepts are analyzed in the second module. In it, the
framework tries to link them to the head elements or to the items of their lists
provided by the concept structure. In order to increment the matches, the tool
uses WordNet [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. It obtains synonyms that might be linked to the head
elements. If the current concept is directly related or conversely one of its synonyms,
the rst one is stored in the list of items of the speci c head element.
Input text Head elements Items in lists Synonyms % Matches
Love 8 1433 5 11%
Death 2 48 0 5%
      </p>
      <p>
        In the case of love text, some of its concepts can be checked easily (e.g.,
a ection is associated to a head element that contains the love concept). The
text that concerns to death has similar situations with other concepts (e.g.,
solitude) but no with the death concept. It happens because of the death concept
is not considered in the color structure as a key (i.e., it is not evaluated in the
literature [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]). The associative learning [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ] solves this situation inserting the
death notion into the list of items of the concepts related to head elements of its
same sentence. Thus, when death appears again it will be matched.
      </p>
      <p>Once the concepts are stored in the concept structure, the palette is produced.
In both cases there are not similar colors to lter so that every head element is
selected in order to generate the paintings. Love painting is composed by eight
di erent colors (i.e., head elements) while the death presents only two colors
(see Table 3). Nevertheless, the amount of pixels in both pictures suggests a
high number of matching with the same head elements and lists of items.</p>
      <p>Regarding the visual e ect, the picture that depicts the love text is noticeably
red with several spots of di erent colors (see Fig. 2). In the second picture
concerned to death text, there are multiple spots with shades of gray. This makes
the painting sad and dull. Therefore, it could be said that visually both pictures
seem to illustrate some of the meanings of the concepts introduced in the texts.</p>
      <p>Finally, delving into a quantitative analysis it can be found that in the text
concerned to love there are more matches related to the head elements of the
concept structure (i.e., more colors are used to draw the painting) than in the
death text. The same occurs in the case of the concepts of the lists of items
(see Table 3). The amount of related synonyms is low in both cases or even
irrelevant (death text does not provide concepts where their synonyms match to
head elements). An enriched color structure in the knowledge database with a
wider list of concepts associated to colors could enhance the problem in future
experiments.
5</p>
    </sec>
    <sec id="sec-5">
      <title>Conclusions</title>
      <p>
        This paper has introduced the CALyPSe framework to generate color palettes
and abstract pictures. These are produced from unstructured texts which are
processed to gather their emotional concepts and associate them to colors using
related literature [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ].
      </p>
      <p>
        The tool consists of three modules (concept extraction, concept storage and
painting generation) and their respective managers. The rst one is in charge
of processing unstructured text using Freeling [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ] and a semantic analyzer.
The second stores the concepts related to colors (i.e., color structure) and the
matchings among these and the notions coming from the input text (i.e., concept
structure) in its knowledge database. It presents an optional feature that eases
the acquisition of extra information. It is based on searching each concept on
Wikipedia. The third is focusing on producing the color palette through color
harmony techniques [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] and drawing the painting.
      </p>
      <p>The case study shows the viability of the proposal using two di erent texts
that have been selected from Wikipedia. They describe concepts as love and
death. Their visual representations are compared observing the di erences among
them. A quantitative analysis is achieved focusing on the amount of concepts
extracted from the texts that match to the head elements provided by the concept
structure, or which ones are stored in the lists of items. Synonyms associated to
the concepts are also considered showing a low hit rate.</p>
      <p>
        More experiments support the proposal but it is still ongoing work with
open issues. New concepts from literature related to the psychology of colors
have to be inserted in the color structure of the knowledge database. This will
allow obtaining higher percentages in the matches among concepts from texts
and head elements. Another point to consider consists of adopting some painting
techniques and image rendering [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] in order to produce more realistic pictures.
      </p>
    </sec>
    <sec id="sec-6">
      <title>Acknowledgements</title>
      <p>This work is funded by ConCreTe. The project ConCreTe acknowledges the
nancial support of the Future and Emerging Technologies (FET) programme
within the Seventh Framework Programme for Research of the European
Commission, under FET grant number 611733.</p>
      <p>This research is funded by the Spanish Ministry of Economy and
Competitiveness and the European Regional Development Fund (TIN2015-66655-R
(MINECO/FEDER)).</p>
    </sec>
  </body>
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