Merge pull request #217 from aurimasv/recognizePDF

Tweak recognizePDF to avoid false positives
This commit is contained in:
Simon Kornblith 2013-01-01 06:21:25 -08:00
commit 3c6b0d99c3

View file

@ -243,7 +243,7 @@ Zotero_RecognizePDF.Recognizer = function () {}
* (function will be passed image as URL and must return text of CAPTCHA)
*/
Zotero_RecognizePDF.Recognizer.prototype.recognize = function(file, libraryID, callback, captchaCallback) {
const MAX_PAGES = 3;
const MAX_PAGES = 5;
this._libraryID = libraryID;
this._callback = callback;
@ -293,10 +293,7 @@ Zotero_RecognizePDF.Recognizer.prototype.recognize = function(file, libraryID, c
intlStream.QueryInterface(Components.interfaces.nsIUnicharLineInputStream);
// get the lines in this sample
var lines = [],
cleanedLines = [],
cleanedLineLengths = [],
str = {};
var lines = [], str = {};
while(intlStream.readLine(str)) {
var line = str.value.trim();
if(line) lines.push(line);
@ -304,20 +301,60 @@ Zotero_RecognizePDF.Recognizer.prototype.recognize = function(file, libraryID, c
inputStream.close();
cacheFile.remove(false);
var me = this;
// look for DOI
var allText = lines.join("\n");
Zotero.debug(allText);
var m = Zotero.Utilities.cleanDOI(allText);
if(m) {
this._DOI = m;
this._queryDOI(m, function() {
me._cleanLines(lines, me._queryGoogle);
});
} else {
this._cleanLines(lines, me._queryGoogle);
}
}
/**
* Looks up item by DOI
* @private
* @param {String} doi DOI to search for
* @param {Function} onFail Callback function to call if a DOI is not found
*/
Zotero_RecognizePDF.Recognizer.prototype._queryDOI = function(doi, onFail) {
var me = this;
var translate = new Zotero.Translate.Search();
translate.setTranslator("11645bd1-0420-45c1-badb-53fb41eeb753");
var item = {"itemType":"journalArticle", "DOI":doi};
translate.setSearch(item);
translate.setHandler("itemDone", function(translate, item) {
me._callback(item);
});
translate.setHandler("select", function(translate, items, callback) {
return me._selectItems(translate, items, callback);
});
translate.setHandler("done", function(translate, success) {
if(!success) onFail.call(me);
});
translate.translate(this._libraryID, false);
}
/**
* Prepares a list of lines that can be used for querying
* The lines are stored in this._goodLines
* @private
* @param {String[]} lines Array of lines
* @param {Function} callback A callback function to be called on completing
*/
Zotero_RecognizePDF.Recognizer.prototype._cleanLines = function(lines, callback) {
// Use only first column from multi-column lines
const lineRe = /^\s*([^\s]+(?: [^\s]+)+)/;
for(var i=0; i<lines.length; i++) {
var cleanedLines = [], cleanedLineLengths = [];
for(var i=0; i<lines.length && cleanedLines.length<30; i++) {
var m = lineRe.exec(lines[i]);
if(m) {
if(m && m[1].split(' ').length > 3) {
cleanedLines.push(m[1]);
cleanedLineLengths.push(m[1].length);
}
@ -334,8 +371,8 @@ Zotero_RecognizePDF.Recognizer.prototype.recognize = function(file, libraryID, c
// pick lines within 4 chars of the median (this is completely arbitrary)
this._goodLines = [];
var uBound = medianLength + 4;
var lBound = medianLength - 4;
var uBound = medianLength + 6;
var lBound = medianLength - 6;
for (var i=0; i<lineLengthsLength; i++) {
if(cleanedLineLengths[i] > lBound && cleanedLineLengths[i] < uBound) {
// Strip quotation marks so they don't mess up search query quoting
@ -344,104 +381,104 @@ Zotero_RecognizePDF.Recognizer.prototype.recognize = function(file, libraryID, c
}
}
this._startLine = this._iteration = 0;
this._queryGoogle();
this._nextLine = this._iteration = 0;
callback.call(this);
}
}
/**
* Deletes hidden browser and sends a failure message to this_callback
* @private
* @param {String} msg Message to be sent to this._callback
*/
Zotero_RecognizePDF.Recognizer.prototype._deleteBrowserAndFail = function(msg) {
var me = this;
try {
if(this._hiddenBrowser) Zotero.Browser.deleteHiddenBrowser(me._hiddenBrowser);
} catch(e) {}
this._callback(false, msg);
}
/**
* Queries Google Scholar for metadata for this PDF
* @private
*/
Zotero_RecognizePDF.Recognizer.prototype._queryGoogle = function() {
if(this._iteration > 3 || this._startLine >= this._goodLines.length) {
try {
if(this._hiddenBrowser) Zotero.Browser.deleteHiddenBrowser(me._hiddenBrowser);
} catch(e) {}
this._callback(false, "recognizePDF.noMatches");
if(this._iteration > 3 || !this._goodLines.length) {
this._deleteBrowserAndFail("recognizePDF.noMatches");
return;
}
this._iteration++;
var queryString = "";
var me = this;
if(this._DOI) {
// use CrossRef to look for DOI
var translate = new Zotero.Translate.Search();
translate.setTranslator("11645bd1-0420-45c1-badb-53fb41eeb753");
var item = {"itemType":"journalArticle", "DOI":this._DOI};
translate.setSearch(item);
translate.setHandler("itemDone", function(translate, item) {
me._callback(item);
});
translate.setHandler("select", function(translate, items, callback) {
return me._selectItems(translate, items, callback);
});
translate.setHandler("done", function(translate, success) {
if(!success) me._queryGoogle();
});
translate.translate(this._libraryID, false);
delete this._DOI;
} else {
// take the relevant parts of some lines (exclude hyphenated word)
var queryStringWords = 0;
while(queryStringWords < 25 && this._startLine < this._goodLines.length) {
var words = this._goodLines[this._startLine].split(/\s+/);
// get rid of first and last words
words.shift();
words.pop();
// make sure there are no long words (probably OCR mistakes)
var skipLine = false;
for(var i=0; i<words.length; i++) {
if(words[i].length > 20) {
skipLine = true;
break;
}
}
// add words to query
if(!skipLine && words.length) {
queryStringWords += words.length;
queryString += '"'+words.join(" ")+'" ';
}
this._startLine++;
// take the relevant parts of some lines (exclude hyphenated word)
var queryStringWords = 0;
while(queryStringWords < 25) {
if(!this._goodLines.length) {
this._deleteBrowserAndFail("recognizePDF.noMatches");
return;
}
Zotero.debug("RecognizePDF: Query string "+queryString);
// pass query string to Google Scholar and translate
var url = "http://scholar.google.com/scholar?q="+encodeURIComponent(queryString)+"&hl=en&lr=&btnG=Search";
if(!this._hiddenBrowser) {
this._hiddenBrowser = Zotero.Browser.createHiddenBrowser();
this._hiddenBrowser.docShell.allowImages = false;
var words = this._goodLines.splice(this._nextLine,1)[0].split(/\s+/);
//Try to avoid picking adjacent strings so the odds of them appearing in another
// document quoting our document is low. Every 7th line is a magic value
this._nextLine = (this._nextLine + 7) % this._goodLines.length;
// get rid of first and last words
words.shift();
words.pop();
// make sure there are no long words (probably OCR mistakes)
var skipLine = false;
for(var i=0; i<words.length; i++) {
if(words[i].length > 20) {
skipLine = true;
break;
}
}
// add words to query
if(!skipLine && words.length) {
queryStringWords += words.length;
queryString += '"'+words.join(" ")+'" ';
}
var translate = new Zotero.Translate.Web();
var savedItem = false;
translate.setTranslator("57a00950-f0d1-4b41-b6ba-44ff0fc30289");
translate.setHandler("itemDone", function(translate, item) {
Zotero.Browser.deleteHiddenBrowser(me._hiddenBrowser);
savedItem = true;
me._callback(item);
});
translate.setHandler("select", function(translate, items, callback) {
me._selectItems(translate, items, callback);
});
translate.setHandler("done", function(translate, success) {
if(!success || !savedItem) me._queryGoogle();
});
translate.setHandler("translators", function(translate, detected) {
if(detected.length) {
translate.translate(me._libraryID, false);
} else {
me._queryGoogle();
}
});
this._hiddenBrowser.addEventListener("pageshow", function() { me._scrape(translate) }, true);
this._hiddenBrowser.loadURIWithFlags(url,
Components.interfaces.nsIWebNavigation.LOAD_FLAGS_BYPASS_HISTORY, null, null, null);
}
Zotero.debug("RecognizePDF: Query string "+queryString);
// pass query string to Google Scholar and translate
var url = "http://scholar.google.com/scholar?q="+encodeURIComponent(queryString)+"&hl=en&lr=&btnG=Search";
if(!this._hiddenBrowser) {
this._hiddenBrowser = Zotero.Browser.createHiddenBrowser();
this._hiddenBrowser.docShell.allowImages = false;
}
var translate = new Zotero.Translate.Web();
var savedItem = false;
translate.setTranslator("57a00950-f0d1-4b41-b6ba-44ff0fc30289");
translate.setHandler("itemDone", function(translate, item) {
Zotero.Browser.deleteHiddenBrowser(me._hiddenBrowser);
savedItem = true;
me._callback(item);
});
translate.setHandler("select", function(translate, items, callback) {
me._selectItems(translate, items, callback);
});
translate.setHandler("done", function(translate, success) {
if(!success || !savedItem) me._queryGoogle();
});
translate.setHandler("translators", function(translate, detected) {
if(detected.length) {
translate.translate(me._libraryID, false);
} else {
me._queryGoogle();
}
});
this._hiddenBrowser.addEventListener("pageshow", function() { me._scrape(translate) }, true);
this._hiddenBrowser.loadURIWithFlags(url,
Components.interfaces.nsIWebNavigation.LOAD_FLAGS_BYPASS_HISTORY, null, null, null);
}
/**