Extracting alt text in context

gistfile1.js

var phrasing = {};
"a abbr area audio b bdi bdo br button canvas cite code command datalist del dfn em embed i iframe img input " +
"ins kbd keygen label map mark math meter noscript object output progress q ruby s samp script select small " +
"span strong sub sup svg textarea time u var video wbr"
    .split(" ")
    .forEach(function (el) { phrasing[el] = true; })
;
function isNotPhrasing (el) {
    if (!el) return true;
    if (el.nodeType !== 1) return true;
    return !phrasing[el.tagName.toLowerCase()];
}

// ... later ...

doc.normalize();
$("img[alt]").each(function () {
    var $img = $(this);
    if (!$img.attr("alt").length) return;
    inc++;
    $img.attr("data-id", inc);
    var $parent;
    $img.parents().each(function () {
        if (isNotPhrasing(this)) {
            $parent = $(this).clone();
            return false;
        }
    });
    var $imgClone = $parent.find("img[data-id=" + inc + "]");
    $imgClone.replaceWith(doc.createTextNode("\u3037" + $imgClone.attr("alt") + "\u3037"));
    var texts = $parent
                    .text()
                    .replace(/\s+/g, " ")
                    .replace(/^\s/, "")
                    .replace(/\s$/, "")
                    .split("\u3037");
    results.push({
        preceding:  texts[0]
    ,   alt:        texts[1]
    ,   following:  texts[2]
    });
});