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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /browser/components/textrecognition/textrecognition.mjs
parentInitial commit. (diff)
downloadfirefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz
firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'browser/components/textrecognition/textrecognition.mjs')
-rw-r--r--browser/components/textrecognition/textrecognition.mjs454
1 files changed, 454 insertions, 0 deletions
diff --git a/browser/components/textrecognition/textrecognition.mjs b/browser/components/textrecognition/textrecognition.mjs
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+window.docShell.chromeEventHandler.classList.add("textRecognitionDialogFrame");
+
+window.addEventListener("DOMContentLoaded", () => {
+ // The arguments are passed in as the final parameters to TabDialogBox.prototype.open.
+ new TextRecognitionModal(...window.arguments);
+});
+
+/**
+ * @typedef {Object} TextRecognitionResult
+ * @property {number} confidence
+ * @property {string} string
+ * @property {DOMQuad} quad
+ */
+
+class TextRecognitionModal {
+ /**
+ * @param {Promise<TextRecognitionResult[]>} resultsPromise
+ * @param {() => {}} resizeVertically
+ * @param {(url: string, where: string, params: Object) => {}} openLinkIn
+ */
+ constructor(resultsPromise, resizeVertically, openLinkIn) {
+ /** @type {HTMLElement} */
+ this.textEl = document.querySelector(".textRecognitionText");
+
+ /** @type {NodeListOf<HTMLElement>} */
+ this.headerEls = document.querySelectorAll(".textRecognitionHeader");
+
+ /** @type {HTMLAnchorElement} */
+ this.linkEl = document.querySelector(
+ "#text-recognition-header-no-results a"
+ );
+
+ this.resizeVertically = resizeVertically;
+ this.openLinkIn = openLinkIn;
+ this.setupLink();
+ this.setupCloseHandler();
+
+ this.showHeaderByID("text-recognition-header-loading");
+
+ resultsPromise.then(
+ ({ results, direction }) => {
+ if (results.length === 0) {
+ // Update the UI to indicate that there were no results.
+ this.showHeaderByID("text-recognition-header-no-results");
+ // It's still worth recording telemetry times, as the API was still invoked.
+ TelemetryStopwatch.finish(
+ "TEXT_RECOGNITION_API_PERFORMANCE",
+ resultsPromise
+ );
+ return;
+ }
+
+ // There were results, cluster them into a nice presentation, and present
+ // the results to the UI.
+ this.runClusteringAndUpdateUI(results, direction);
+ this.showHeaderByID("text-recognition-header-results");
+ TelemetryStopwatch.finish(
+ "TEXT_RECOGNITION_API_PERFORMANCE",
+ resultsPromise
+ );
+
+ TextRecognitionModal.recordInteractionTime();
+ },
+ error => {
+ // There was an error in the text recognition call. Treat this as the same
+ // as if there were no results, but report the error to the console and telemetry.
+ this.showHeaderByID("text-recognition-header-no-results");
+
+ console.error(
+ "There was an error recognizing the text from an image.",
+ error
+ );
+ Services.telemetry.scalarAdd(
+ "browser.ui.interaction.textrecognition_error",
+ 1
+ );
+ TelemetryStopwatch.cancel(
+ "TEXT_RECOGNITION_API_PERFORMANCE",
+ resultsPromise
+ );
+ }
+ );
+ }
+
+ /**
+ * After the results are shown, measure how long a user interacts with the modal.
+ */
+ static recordInteractionTime() {
+ TelemetryStopwatch.start(
+ "TEXT_RECOGNITION_INTERACTION_TIMING",
+ // Pass the instance of the window in case multiple tabs are doing text recognition
+ // and there is a race condition.
+ window
+ );
+
+ const finish = () => {
+ TelemetryStopwatch.finish("TEXT_RECOGNITION_INTERACTION_TIMING", window);
+ window.removeEventListener("blur", finish);
+ window.removeEventListener("unload", finish);
+ };
+
+ // The user's focus went away, record this as the total interaction, even if they
+ // go back and interact with it more. This can be triggered by doing actions like
+ // clicking the URL bar, or by switching tabs.
+ window.addEventListener("blur", finish);
+
+ // The modal is closed.
+ window.addEventListener("unload", finish);
+ }
+
+ /**
+ * After the results are shown, measure how long a user interacts with the modal.
+ * @param {number} textLength
+ */
+ static recordTextLengthTelemetry(textLength) {
+ const histogram = Services.telemetry.getHistogramById(
+ "TEXT_RECOGNITION_TEXT_LENGTH"
+ );
+ histogram.add(textLength);
+ }
+
+ setupCloseHandler() {
+ document
+ .querySelector("#text-recognition-close")
+ .addEventListener("click", () => {
+ window.close();
+ });
+ }
+
+ /**
+ * Apply the variables for the support.mozilla.org URL.
+ */
+ setupLink() {
+ this.linkEl.href = Services.urlFormatter.formatURL(this.linkEl.href);
+ this.linkEl.addEventListener("click", event => {
+ event.preventDefault();
+ this.openLinkIn(this.linkEl.href, "tab", {
+ forceForeground: true,
+ triggeringPrincipal:
+ Services.scriptSecurityManager.getSystemPrincipal(),
+ });
+ });
+ }
+
+ /**
+ * A helper to only show the appropriate header.
+ *
+ * @param {string} id
+ */
+ showHeaderByID(id) {
+ for (const header of this.headerEls) {
+ header.style.display = "none";
+ }
+
+ document.getElementById(id).style.display = "";
+ this.resizeVertically();
+ }
+
+ /**
+ * @param {string} text
+ */
+ static copy(text) {
+ const clipboard = Cc["@mozilla.org/widget/clipboardhelper;1"].getService(
+ Ci.nsIClipboardHelper
+ );
+ clipboard.copyString(text);
+ }
+
+ /**
+ * Cluster the text based on its visual position.
+ *
+ * @param {TextRecognitionResult[]} results
+ * @param {"ltr" | "rtl"} direction
+ */
+ runClusteringAndUpdateUI(results, direction) {
+ /** @type {Vec2[]} */
+ const centers = [];
+
+ for (const result of results) {
+ const p = result.quad;
+
+ // Pick either the left-most or right-most edge. This optimizes for
+ // aligned text over centered text.
+ const minOrMax = direction === "ltr" ? Math.min : Math.max;
+
+ centers.push([
+ minOrMax(p.p1.x, p.p2.x, p.p3.x, p.p4.x),
+ (p.p1.y, p.p2.y, p.p3.y, p.p4.y) / 4,
+ ]);
+ }
+
+ const distSq = new DistanceSquared(centers);
+
+ // The values are ranged 0 - 1. This value might be able to be determined
+ // algorithmically.
+ const averageDistance = Math.sqrt(distSq.quantile(0.2));
+ const clusters = densityCluster(
+ centers,
+ // Neighborhood radius:
+ averageDistance,
+ // Minimum points to form a cluster:
+ 2
+ );
+
+ let text = "";
+ for (const cluster of clusters) {
+ const pCluster = document.createElement("p");
+ pCluster.className = "textRecognitionTextCluster";
+
+ for (let i = 0; i < cluster.length; i++) {
+ const index = cluster[i];
+ const { string } = results[index];
+ if (i + 1 === cluster.length) {
+ // Each cluster could be a paragraph, so add newlines to the end
+ // for better copying.
+ text += string + "\n\n";
+ // The paragraph tag automatically uses two newlines.
+ pCluster.innerText += string;
+ } else {
+ // This text is assumed to be a newlines in a paragraph, so only needs
+ // to be separated by a space.
+ text += string + " ";
+ pCluster.innerText += string + " ";
+ }
+ }
+ this.textEl.appendChild(pCluster);
+ }
+
+ this.textEl.style.display = "block";
+
+ text = text.trim();
+ TextRecognitionModal.copy(text);
+ TextRecognitionModal.recordTextLengthTelemetry(text.length);
+ }
+}
+
+/**
+ * A two dimensional vector.
+ *
+ * @typedef {[number, number]} Vec2
+ */
+
+/**
+ * @typedef {number} PointIndex
+ */
+
+/**
+ * An implementation of the DBSCAN clustering algorithm.
+ *
+ * https://en.wikipedia.org/wiki/DBSCAN#Algorithm
+ *
+ * @param {Vec2[]} points
+ * @param {number} distance
+ * @param {number} minPoints
+ * @returns {Array<PointIndex[]>}
+ */
+function densityCluster(points, distance, minPoints) {
+ /**
+ * A flat of array of labels that match the index of the points array. The values have
+ * the following meaning:
+ *
+ * undefined := No label has been assigned
+ * "noise" := Noise is a point that hasn't been clustered.
+ * number := Cluster index
+ *
+ * @type {undefined | "noise" | Index}
+ */
+ const labels = Array(points.length);
+ const noiseLabel = "noise";
+
+ let nextClusterIndex = 0;
+
+ // Every point must be visited at least once. Often they will be visited earlier
+ // in the interior of the loop.
+ for (let pointIndex = 0; pointIndex < points.length; pointIndex++) {
+ if (labels[pointIndex] !== undefined) {
+ // This point is already labeled from the interior logic.
+ continue;
+ }
+
+ // Get the neighbors that are within the range of the epsilon value, includes
+ // the current point.
+ const neighbors = getNeighborsWithinDistance(points, distance, pointIndex);
+
+ if (neighbors.length < minPoints) {
+ labels[pointIndex] = noiseLabel;
+ continue;
+ }
+
+ // Start a new cluster.
+ const clusterIndex = nextClusterIndex++;
+ labels[pointIndex] = clusterIndex;
+
+ // Fill the cluster. The neighbors array grows.
+ for (let i = 0; i < neighbors.length; i++) {
+ const nextPointIndex = neighbors[i];
+ if (typeof labels[nextPointIndex] === "number") {
+ // This point was already claimed, ignore it.
+ continue;
+ }
+
+ if (labels[nextPointIndex] === noiseLabel) {
+ // Claim this point and move on since noise has no neighbors.
+ labels[nextPointIndex] = clusterIndex;
+ continue;
+ }
+
+ // Claim this point as part of this cluster.
+ labels[nextPointIndex] = clusterIndex;
+
+ const newNeighbors = getNeighborsWithinDistance(
+ points,
+ distance,
+ nextPointIndex
+ );
+
+ if (newNeighbors.length >= minPoints) {
+ // Add on to the neighbors if more are found.
+ for (const newNeighbor of newNeighbors) {
+ if (!neighbors.includes(newNeighbor)) {
+ neighbors.push(newNeighbor);
+ }
+ }
+ }
+ }
+ }
+
+ const clusters = [];
+
+ // Pre-populate the clusters.
+ for (let i = 0; i < nextClusterIndex; i++) {
+ clusters[i] = [];
+ }
+
+ // Turn the labels into clusters, adding the noise to the end.
+ for (let pointIndex = 0; pointIndex < labels.length; pointIndex++) {
+ const label = labels[pointIndex];
+ if (typeof label === "number") {
+ clusters[label].push(pointIndex);
+ } else if (label === noiseLabel) {
+ // Add a single cluster.
+ clusters.push([pointIndex]);
+ } else {
+ throw new Error("Logic error. Expected every point to have a label.");
+ }
+ }
+
+ clusters.sort((a, b) => points[b[0]][1] - points[a[0]][1]);
+
+ return clusters;
+}
+
+/**
+ * @param {Vec2[]} points
+ * @param {number} distance
+ * @param {number} index,
+ * @returns {Index[]}
+ */
+function getNeighborsWithinDistance(points, distance, index) {
+ let neighbors = [index];
+ // There is no reason to compute the square root here if we square the
+ // original distance.
+ const distanceSquared = distance * distance;
+
+ for (let otherIndex = 0; otherIndex < points.length; otherIndex++) {
+ if (otherIndex === index) {
+ continue;
+ }
+ const a = points[index];
+ const b = points[otherIndex];
+ const dx = a[0] - b[0];
+ const dy = a[1] - b[1];
+
+ if (dx * dx + dy * dy < distanceSquared) {
+ neighbors.push(otherIndex);
+ }
+ }
+
+ return neighbors;
+}
+
+/**
+ * This class pre-computes the squared distances to allow for efficient distance lookups,
+ * and it provides a way to look up a distance quantile.
+ */
+class DistanceSquared {
+ /** @type {Map<number>} */
+ #distances = new Map();
+ #list;
+ #distancesSorted;
+
+ /**
+ * @param {Vec2[]} list
+ */
+ constructor(list) {
+ this.#list = list;
+ for (let aIndex = 0; aIndex < list.length; aIndex++) {
+ for (let bIndex = aIndex + 1; bIndex < list.length; bIndex++) {
+ const id = this.#getTupleID(aIndex, bIndex);
+ const a = this.#list[aIndex];
+ const b = this.#list[bIndex];
+ const dx = a[0] - b[0];
+ const dy = a[1] - b[1];
+ this.#distances.set(id, dx * dx + dy * dy);
+ }
+ }
+ }
+
+ /**
+ * Returns a unique tuple ID to identify the relationship between two vectors.
+ */
+ #getTupleID(aIndex, bIndex) {
+ return aIndex < bIndex
+ ? aIndex * this.#list.length + bIndex
+ : bIndex * this.#list.length + aIndex;
+ }
+
+ /**
+ * Returns the distance squared between two vectors.
+ *
+ * @param {Index} aIndex
+ * @param {Index} bIndex
+ * @returns {number} The distance squared
+ */
+ get(aIndex, bIndex) {
+ return this.#distances.get(this.#getTupleID(aIndex, bIndex));
+ }
+
+ /**
+ * Returns the quantile squared.
+ *
+ * @param {number} percentile - Ranged between 0 - 1
+ * @returns {number}
+ */
+ quantile(percentile) {
+ if (!this.#distancesSorted) {
+ this.#distancesSorted = [...this.#distances.values()].sort(
+ (a, b) => a - b
+ );
+ }
+ const index = Math.max(
+ 0,
+ Math.min(
+ this.#distancesSorted.length - 1,
+ Math.round(this.#distancesSorted.length * percentile)
+ )
+ );
+ return this.#distancesSorted[index];
+ }
+}