Update third_party/document_image_extractor

third_party/document_image_extractor/third_party/src/document_image_extractor.js

Index: third_party/document_image_extractor/third_party/src/document_image_extractor.js
diff --git a/third_party/document_image_extractor/third_party/src/document_image_extractor.js b/third_party/document_image_extractor/third_party/src/document_image_extractor.js
deleted file mode 100644
index d82702d741d98a71ba53c5fcb91fd0626818d38d..0000000000000000000000000000000000000000
--- a/third_party/document_image_extractor/third_party/src/document_image_extractor.js
+++ /dev/null
@@ -1,400 +0,0 @@
-goog.provide('image.collections.extension.DocumentImageExtractor');
-
-goog.require('goog.Uri');
-goog.require('goog.asserts');
-goog.require('goog.dom');
-goog.require('goog.log');
-goog.require('goog.math.Size');
-goog.require('goog.object');
-goog.require('goog.string');
-goog.require('goog.style');
-goog.require('goog.uri.utils');
-goog.require('gws.collections.common.Constants');
-goog.require('image.collections.extension.AdElementFilter');
-goog.require('image.collections.extension.DocumentFeature');
-goog.require('image.collections.extension.DocumentFeatureExtractor');
-goog.require('image.collections.extension.DocumentImage');
-goog.require('image.collections.extension.VisibleElementFilter');
-
-goog.scope(function() {
-var AdElementFilter = image.collections.extension.AdElementFilter;
-var Constants = gws.collections.common.Constants;
-var DocumentFeature = image.collections.extension.DocumentFeature;
-var DocumentFeatureExtractor =
-    image.collections.extension.DocumentFeatureExtractor;
-var DocumentImage = image.collections.extension.DocumentImage;
-var CustomAttribute = DocumentImage.CustomAttribute;
-var VisibleElementFilter = image.collections.extension.VisibleElementFilter;
-
-
-
-/**
- * This class is used for extracting a salient image from an HTML document.
- * @extends {DocumentFeatureExtractor}
- * @constructor
- */
-image.collections.extension.DocumentImageExtractor = function() {
-  DocumentImageExtractor.base(this, 'constructor');
-
-  this.addFilter(new AdElementFilter());
-  this.addFilter(new VisibleElementFilter());
-};
-goog.inherits(image.collections.extension.DocumentImageExtractor,
-    DocumentFeatureExtractor);
-var DocumentImageExtractor = image.collections.extension.DocumentImageExtractor;
-goog.addSingletonGetter(DocumentImageExtractor);
-
-
-/** @private {goog.log.Logger} Extractor logger. */
-DocumentImageExtractor.logger_ = goog.log.getLogger(
-    'image.collections.extension.DocumentImageExtractor');
-
-
-/** @enum {number} */
-DocumentImageExtractor.Parameters = {
-  AREA_MULTIPLIER: -1e-5,
-  ASPECT_RATIO_DEMOTION_FACTOR: 0.8,
-  MAX_ASPECT_RATIO: 2,
-  MAX_ELEMENTS_WITH_BACKGROUND: 30,
-  MAX_OFFSET: 2000,
-  NON_TOPLEVEL_DEMOTION_FACTOR: 0.5,
-  OFFSET_MULTIPLIER: 1e-3,
-  WEIGHT_APPLE: 0.7,
-  WEIGHT_MICRODATA: 0.55,
-  WEIGHT_MICROSOFT: 0.9,
-  WEIGHT_OPEN_GRAPH: 1.0,
-  WEIGHT_SRC: 0.6,
-  WEIGHT_TWITTER: 0.8
-};
-var Parameters = DocumentImageExtractor.Parameters;
-
-
-/**
- * Map of image type to relevance multiplier.
- * @private {!Object.<string, number>}
- */
-DocumentImageExtractor.IMAGE_TYPE_RELEVANCE_MULTIPLIER_ =
-    goog.object.create('.gif', 0.5);
-
-
-
-/** @constructor */
-DocumentImageExtractor.Context = function() {
-  /** @type {number} */
-  this.numElementsWithBackground = 0;
-
-  /** @type {!Object.<string, number>} */
-  this.urlToRelevance = {};
-};
-var Context = DocumentImageExtractor.Context;
-
-
-/**
- * Extracts salient images from an HTML document.
- * @param {!Document} doc
- * @return {!Array.<!DocumentImage>}
- * @override
- */
-DocumentImageExtractor.prototype.extractAllFromDocument = function(doc) {
-  var context = new Context();
-  return this.extractFromNodeList(doc.getElementsByTagName('*'), context);
-};
-
-
-/**
- * Extracts a salient image from an HTML element, returns null if failed.
- * @param {!Element} element HTML element.
- * @param {Object=} opt_context Optional context.
- * @return {DocumentImage}
- * @override
- */
-DocumentImageExtractor.prototype.extractFromElement = function(
-    element, opt_context) {
-  var image = null;
-  switch (element.tagName.toLowerCase()) {
-    case 'meta':
-      image = this.extractOpenGraphImage_(element) ||
-          this.extractMicrosoftImage_(element) ||
-          this.extractTwitterImage_(element) ||
-          this.extractMicrodataImage_(element);
-      break;
-    case 'link':
-      image = this.extractAppleImage_(element) ||
-          this.extractImageSrcImage_(element) ||
-          this.extractMicrodataImage_(element);
-      break;
-    case 'img':
-      if (this.filter(element)) {
-        image = this.extractImage_(element);
-      }
-      break;
-    default:
-      if (this.filter(element) && opt_context.numElementsWithBackground <
-          Parameters.MAX_ELEMENTS_WITH_BACKGROUND) {
-        image = this.extractBackgroundImage_(element);
-        if (image) {
-          ++opt_context.numElementsWithBackground;
-        }
-      }
-  }
-
-  if (!image) {
-    return null;
-  }
-
-  var size = image.getDisplaySize() || image.getSize();
-  goog.asserts.assert(!goog.isNull(size));
-  if (image.getUrl() != document.location.href) {
-    // Ignore images that are too small.
-    if (size.width < Constants.EXTRACT_MIN_WIDTH ||
-        size.height < Constants.EXTRACT_MIN_HEIGHT) {
-      return null;
-    }
-  }
-  // Demote smaller images (squash area using the sigmoid function).
-  var relevance = image.getRelevance();
-  relevance /= (1 + Math.exp(Parameters.AREA_MULTIPLIER * size.area()));
-  // Demote images with bad aspect ratio.
-  var aspectRatio = size.aspectRatio();
-  if (aspectRatio < 1) {
-    aspectRatio = 1 / aspectRatio;
-  }
-  if (aspectRatio > Parameters.MAX_ASPECT_RATIO) {
-    relevance *= Parameters.ASPECT_RATIO_DEMOTION_FACTOR;
-  }
-
-  // TODO(busaryev): use the following features:
-  // - relative size of the image comparing to neighbors;
-  // - area of the visible portion of the image;
-  // - position (demote images on the border of the page).
-
-  var url = image.getUrl();
-  try {
-    // Make sure that image url is absolute.
-    var documentUrl = goog.dom.getOwnerDocument(element).documentURI;
-    url = goog.Uri.resolve(documentUrl, url).toString();
-  } catch (e) {
-    goog.log.info(DocumentImageExtractor.logger_,
-        'Cannot resolve url: ' + url);
-    return null;
-  }
-
-  var imagePath = goog.string.makeSafe(goog.uri.utils.getPath(url));
-  var lastDot = imagePath.lastIndexOf('.');
-  if (lastDot > 0) {
-    var imageType = imagePath.slice(lastDot);
-    var multiplier =
-        DocumentImageExtractor.IMAGE_TYPE_RELEVANCE_MULTIPLIER_[imageType];
-    if (multiplier) {
-      relevance *= multiplier;
-    }
-  }
-
-  if (url in opt_context.urlToRelevance &&
-      opt_context.urlToRelevance[url] > relevance) {
-    return null;
-  }
-  opt_context.urlToRelevance[url] = relevance;
-  return new DocumentImage(relevance, url, image.getSize(),
-      image.getDisplaySize());
-};
-
-
-/**
- * @param {!Element} element
- * @return {DocumentImage}
- * @private
- */
-DocumentImageExtractor.prototype.extractOpenGraphImage_ = function(element) {
-  return this.extractCanonicalImage_(
-      element, Parameters.WEIGHT_OPEN_GRAPH, 'property', 'og:image', 'content');
-};
-
-
-/**
- * @param {!Element} element
- * @return {DocumentImage}
- * @private
- */
-DocumentImageExtractor.prototype.extractMicrosoftImage_ = function(element) {
-  return this.extractCanonicalImage_(element, Parameters.WEIGHT_MICROSOFT,
-      'name', 'msapplication-tileimage', 'content');
-};
-
-
-/**
- * @param {!Element} element
- * @return {DocumentImage}
- * @private
- */
-DocumentImageExtractor.prototype.extractTwitterImage_ = function(element) {
-  return this.extractCanonicalImage_(
-      element, Parameters.WEIGHT_TWITTER, 'name', 'twitter:image', 'content');
-};
-
-
-/**
- * @param {!Element} element
- * @return {DocumentImage}
- * @private
- */
-DocumentImageExtractor.prototype.extractAppleImage_ = function(element) {
-  return this.extractCanonicalImage_(
-      element, Parameters.WEIGHT_APPLE, 'rel', 'apple-touch-icon', 'href');
-};
-
-
-/**
- * @param {!Element} element
- * @return {DocumentImage}
- * @private
- */
-DocumentImageExtractor.prototype.extractImageSrcImage_ = function(element) {
-  return this.extractCanonicalImage_(
-      element, Parameters.WEIGHT_SRC, 'rel', 'image_src', 'href');
-};
-
-
-/**
- * @param {!Element} element
- * @param {!number} relevance
- * @param {string} attributeName
- * @param {string} attribute
- * @param {string} urlAttributeName
- * @return {DocumentImage}
- * @private
- */
-DocumentImageExtractor.prototype.extractCanonicalImage_ = function(
-    element, relevance, attributeName, attribute, urlAttributeName) {
-  goog.asserts.assert(goog.isNumber(relevance));
-  goog.asserts.assert(goog.isString(attributeName));
-  goog.asserts.assert(goog.isString(attribute));
-
-  if (goog.string.caseInsensitiveEquals(
-      goog.string.makeSafe(element.getAttribute(attributeName)), attribute)) {
-    var url = element.getAttribute(urlAttributeName);
-    if (!url || goog.string.startsWith(url, 'data:')) {
-      return null;
-    }
-    var width = goog.string.parseInt(
-        element.getAttribute(CustomAttribute.WIDTH));
-    var height = goog.string.parseInt(
-        element.getAttribute(CustomAttribute.HEIGHT));
-    if (width && height) {
-      // For non-toplevel urls, demote the image if it is not in the document.
-      var ownerDocument = goog.dom.getOwnerDocument(element);
-      if (goog.uri.utils.getPath(ownerDocument.documentURI) != '/' &&
-          ownerDocument.body.innerHTML.indexOf(url) == -1) {
-        relevance *= Parameters.NON_TOPLEVEL_DEMOTION_FACTOR;
-      }
-      var size = new goog.math.Size(width, height);
-      return new DocumentImage(relevance, url, size);
-    }
-  }
-  return null;
-};
-
-
-/**
- * @param {!Element} element
- * @return {DocumentImage}
- * @private
- */
-DocumentImageExtractor.prototype.extractMicrodataImage_ = function(element) {
-  var itemProp = element.getAttribute('itemprop');
-  if (itemProp && itemProp.toLowerCase() == 'thumbnailurl') {
-    var url = element.getAttribute('href') || element.getAttribute('content');
-    if (!url || goog.string.startsWith(url, 'data:')) {
-      return null;
-    }
-    var width = goog.string.parseInt(
-        element.getAttribute(CustomAttribute.WIDTH));
-    var height = goog.string.parseInt(
-        element.getAttribute(CustomAttribute.HEIGHT));
-    if (width && height) {
-      var size = new goog.math.Size(width, height);
-      return new DocumentImage(Parameters.WEIGHT_MICRODATA, url, size);
-    }
-  }
-  return null;
-};
-
-
-/**
- * @param {!Element} element
- * @return {number}
- * @private
- */
-DocumentImageExtractor.prototype.getElementRelevance_ = function(element) {
-  var offset = goog.style.getPageOffsetTop(element);
-  if (offset > Parameters.MAX_OFFSET) {
-    return 0;
-  }
-  return 1 / (1 + Math.exp(Parameters.OFFSET_MULTIPLIER * offset));
-};
-
-
-/**
- * Extracts an image from the <img> HTML element.
- * @param {!Element} element
- * @return {DocumentImage}
- * @private
- */
-DocumentImageExtractor.prototype.extractImage_ = function(element) {
-  goog.asserts.assert(element.tagName.toLowerCase() == 'img');
-  var url = element.src;
-  // We cannot handle data URIs.
-  if (url && !goog.string.startsWith(url, 'data:')) {
-    var naturalSize = new goog.math.Size(
-        element.naturalWidth, element.naturalHeight);
-    var displaySize = goog.style.getSize(element);
-    var size = naturalSize.area() < displaySize.area() ?
-        naturalSize : displaySize;
-    if (size.width && size.height) {
-      var relevance = this.getElementRelevance_(element);
-      return new DocumentImage(relevance, url, naturalSize, displaySize);
-    }
-  }
-  return null;
-};
-
-
-/**
- * Extracts an image specified in 'background-image' property of an element.
- * @param {!Element} element
- * @return {DocumentImage}
- * @private
- */
-DocumentImageExtractor.prototype.extractBackgroundImage_ = function(element) {
-  var backgroundImage = goog.style.getComputedStyle(
-      element, 'background-image');
-  var backgroundRepeat = goog.style.getComputedStyle(
-      element, 'background-repeat');
-  var backgroundSize = goog.style.getComputedStyle(
-      element, 'background-size');
-  if (backgroundImage &&
-      (backgroundRepeat == 'no-repeat' || backgroundSize == 'cover') &&
-      goog.string.startsWith(backgroundImage, 'url(') &&
-      goog.string.endsWith(backgroundImage, ')')) {
-    var url = backgroundImage.substr(4, backgroundImage.length - 5);
-    if (url && !goog.string.startsWith(url, 'data:')) {
-      var size = goog.style.getSize(element);
-      if (size.width && size.height) {
-        var relevance = this.getElementRelevance_(element);
-        var children = goog.dom.getChildren(element);
-        for (var i = 0; i < children.length; ++i) {
-          var child = children[i];
-          if (goog.style.getComputedStyle(child, 'display') != 'none' &&
-              goog.style.getSize(child).area() > 0.1 * size.area()) {
-            relevance *= 0.1;
-            break;
-          }
-        }
-        return new DocumentImage(relevance, url,
-            undefined /* image size is unknown */, size);
-      }
-    }
-  }
-  return null;
-};
-});  // goog.scope