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How to use pixelmatch method in Playwright Internal
Best JavaScript code snippet using playwright-internal
launcher.js
Source:launcher.js 
...74 log.warn('Different dimension of baseline and current screenshot skipping the test');75 inst.skip();76 }77 const diff = new PNG({ width, height });78 const mismatchedPixels = pixelmatch(baseImage.data, currentImage.data, diff.data, width, height, { threshold: 0.3, includeAA: true });79 log.debug($`Comparing screenshots ${screenshotPath} and ${baseScreenshotPath}`);80 writePng(this.pathUtils.getScreenshotPath(viewportSize, screenshotName, SCREENSHOTTYPES.DIFF, screenshotDirectory), diff);81 return comparisonStrategy(mismatchedPixels, width, height, config);82 }83 after(exitCode, config, capabilities) {84 // TODO: something after all tests are run85 }86 beforeTest(test, context) {87 this.currentContext = context;88 }89 beforeScenario(test, context) {90 // TODO: something before each Cucumber scenario run91 }92}...
index.js
Source:index.js
...48 if(err) return callback(err);49 const tile1 = tiles[0];50 const tile2 = tiles[1];51 const diffTile = new PNG({width: tile1.width, height: tile1.height});52 const diffs = pixelmatch(tile1.data, tile2.data, diffTile.data, diffTile.width, diffTile.height);53 const buffer = PNG.sync.write(diffTile);54 callback(null, buffer);55 });56 }57 Pixelmatch.prototype.getTile = function(z, x, y, callback) {58 return getDiffTile(this.sources, z, x, y, function(err, tile) {59 if (err) return callback(err);60 return callback(null, tile, {61 "Content-Type": "image/png",62 });63 });64 };65 Pixelmatch.prototype.getInfo = function(callback) {66 var info = this.sources...
browser.js
Source:browser.js
...34 const w = img2.width;35 const img1Ctx = imageToCanvasContext(img1);36 const img2Ctx = imageToCanvasContext(img2);37 const pixelmatchResultImgData = getEmptyImgData(h, w);38 pixelmatch(39 getImgDataDataFromContext(img1Ctx),40 getImgDataDataFromContext(img2Ctx),41 pixelmatchResultImgData.data,42 w,43 h, 44 { threshold: .1, includeAA: true }45 );46 console.time("pixelmatchResult");47 const pixelmatchResult = imageToCanvasContext(null, w, h);48 pixelmatchResult.putImageData(pixelmatchResultImgData, 0, 0);49 console.timeEnd("pixelmatchResult");50 console.time("diverged");51 const divergedImgData = diverged(getImgDataDataFromContext(img1Ctx), getImgDataDataFromContext(img2Ctx), h, w);52 console.timeEnd("diverged");...
test.js
Source:test.js
...18 it('runs dilation example', function () {19 execSync('node ./examples/dilation.js');20 const expectedOutput = PNG.sync.read(fs.readFileSync('./examples/expected-output/dilation.png'));21 const testOutput = PNG.sync.read(fs.readFileSync('./examples/test-output/dilation.png'));22 const pixelmatchResult = pixelmatch(expectedOutput.data, testOutput.data, null, expectedOutput.width, expectedOutput.height, {threshold: 0.01});23 assert.deepStrictEqual(pixelmatchResult, 0);24 });25 it('runs template matching example', function () {26 execSync('node ./examples/templateMatching.js');27 const expectedOutput = PNG.sync.read(fs.readFileSync('./examples/expected-output/template-matching.png'));28 const testOutput = PNG.sync.read(fs.readFileSync('./examples/test-output/template-matching.png'));29 const pixelmatchResult = pixelmatch(expectedOutput.data, testOutput.data, null, expectedOutput.width, expectedOutput.height, {threshold: 0.01});30 assert.deepStrictEqual(pixelmatchResult, 0);31 });32});33describe('cvTranslateError', function() {34 it('translates error correctly', async function () {35 const errString = await errorExample();36 assert.deepStrictEqual(errString, 37 "Exception: OpenCV(4.3.0) /code/modules/imgproc/src/contours.cpp:197: error: (-210:Unsupported format or combination of formats) [Start]FindContours supports only CV_8UC1 images when mode != CV_RETR_FLOODFILL otherwise supports CV_32SC1 images only in function 'cvStartFindContours_Impl'\n");38 });...
extension.js
Source:extension.js
...31 img1 = await img1.raw().toBuffer();32 img2 = await img2.raw().toBuffer();33 const diff = Buffer.alloc(w*h*4);34 // compare with pixelmatch35 const result = pixelmatch(img1, img2, diff, w, h, {threshold: args[3]});36 // write difference to filename given as argument37 await sharp(diff, {raw: {width: w, height: h, channels: 4}})38 .toFile(args[2]);39 // return difference in pixels also as percentage from widht and height40 const mis_percent = (result * 100) / (w * h);41 return [result, mis_percent.toFixed(2)];42}43exports.__esModule = true;...
output.js
Source:output.js
1[2 "node_modules/pixelmatch/bin/pixelmatch",3 "node_modules/pixelmatch/index.js",4 "node_modules/pixelmatch/node_modules/pngjs/lib/bitmapper.js",5 "node_modules/pixelmatch/node_modules/pngjs/lib/bitpacker.js",6 "node_modules/pixelmatch/node_modules/pngjs/lib/chunkstream.js",7 "node_modules/pixelmatch/node_modules/pngjs/lib/constants.js",8 "node_modules/pixelmatch/node_modules/pngjs/lib/crc.js",9 "node_modules/pixelmatch/node_modules/pngjs/lib/filter-pack.js",10 "node_modules/pixelmatch/node_modules/pngjs/lib/filter-parse-async.js",11 "node_modules/pixelmatch/node_modules/pngjs/lib/filter-parse-sync.js",12 "node_modules/pixelmatch/node_modules/pngjs/lib/filter-parse.js",13 "node_modules/pixelmatch/node_modules/pngjs/lib/format-normaliser.js",14 "node_modules/pixelmatch/node_modules/pngjs/lib/interlace.js",15 "node_modules/pixelmatch/node_modules/pngjs/lib/packer-async.js",16 "node_modules/pixelmatch/node_modules/pngjs/lib/packer-sync.js",17 "node_modules/pixelmatch/node_modules/pngjs/lib/packer.js",18 "node_modules/pixelmatch/node_modules/pngjs/lib/paeth-predictor.js",19 "node_modules/pixelmatch/node_modules/pngjs/lib/parser-async.js",20 "node_modules/pixelmatch/node_modules/pngjs/lib/parser-sync.js",21 "node_modules/pixelmatch/node_modules/pngjs/lib/parser.js",22 "node_modules/pixelmatch/node_modules/pngjs/lib/png-sync.js",23 "node_modules/pixelmatch/node_modules/pngjs/lib/png.js",24 "node_modules/pixelmatch/node_modules/pngjs/lib/sync-inflate.js",25 "node_modules/pixelmatch/node_modules/pngjs/lib/sync-reader.js",26 "node_modules/pixelmatch/node_modules/pngjs/package.json",27 "node_modules/pixelmatch/package.json",28 "package.json",29 "test/unit/pixelmatch/input.js"...
cssRegression.js
Source:cssRegression.js
...22 const expectedImg = PNG.sync.read(fs.readFileSync(expectedPath));23 (actualImg = PNG.sync.read(fs.readFileSync(actualPath))),24 ({ width, height } = expectedImg),25 (diffImg = new PNG({ width, height })),26 (res = pixelmatch(expectedImg.data, actualImg.data, diffImg.data, width, height, {27 threshold: pixelmatchOpts.threshold,28 diffColor: pixelmatchOpts.diffColor,29 aaColor: pixelmatchOpts.aaColor,30 includeAA: pixelmatchOpts.includeAA,31 }));32 addAttach('../snapshots/actual/' + filename + '.png', 'actual');33 addAttach('../snapshots/diff/' + filename + '.png', 'diff');34 addAttach('../snapshots/expected/' + filename + '.png', 'expected');35 // alternative36 // diffImg.pack().pipe( fs.createWriteStream( diffPath ) );37 fs.writeFileSync(diffPath, PNG.sync.write(diffImg));38 return res;39 };40};
get-pixelmatch-args-spec.js
Source:get-pixelmatch-args-spec.js
1'use strict';2const getPixelmatchArgs = require('../../src/util/get-pixelmatch-args');3describe('getPixelmatchArgs', () => {4 describe('threshold', () => {5 it('converts tolerance by dividing by ten', () => {6 expect(getPixelmatchArgs({tolerance: 5})).toEqual({threshold: 0.5});7 expect(getPixelmatchArgs({tolerance: 1})).toEqual({threshold: 0.1});8 expect(getPixelmatchArgs({tolerance: 10})).toEqual({threshold: 1});9 expect(getPixelmatchArgs({})).toEqual({threshold: 0.1});10 });11 it('limits between 0.1 and 1', () => {12 expect(getPixelmatchArgs({tolerance: 20})).toEqual({threshold: 1});13 expect(getPixelmatchArgs({tolerance: 0})).toEqual({threshold: 0.1});14 expect(getPixelmatchArgs({tolerance: 0.1})).toEqual({threshold: 0.1});15 });16 });...
Using AI Code Generation
1const { chromium } = require('playwright');2(async () => {3 const browser = await chromium.launch();4 const context = await browser.newContext();5 const page = await context.newPage();6 await page.screenshot({ path: 'example.png' });7 const image = await page.screenshot();8 const buffer = await image.buffer();9 const fs = require('fs');10 fs.writeFileSync('example.png', buffer);11 await browser.close();12})();13const { chromium } = require('playwright');14(async () => {15 const browser = await chromium.launch();16 const context = await browser.newContext();17 const page = await context.newPage();18 await page.screenshot({ path: 'example.png' });19 const image = await page.screenshot();20 const buffer = await image.buffer();21 const fs = require('fs');22 fs.writeFileSync('example.png', buffer);23 const pixelmatch = require('pixelmatch');24 const PNG = require('pngjs').PNG;25 const fs = require('fs');26 const img1 = fs.createReadStream('example.png').pipe(new PNG()).on('parsed', doneReading);27 const img2 = fs.createReadStream('example.png').pipe(new PNG()).on('parsed', doneReading);28 let filesRead = 0;29 function doneReading() {30 if (++filesRead < 2) return;31 const diff = new PNG({ width: img1.width, height: img1.height });32 const numDiffPixels = pixelmatch(img1.data, img2.data, diff.data, img1.width, img1.height, { threshold: 0.1 });33 console.log(`${numDiffPixels} different pixels`);34 diff.pack().pipe(fs.createWriteStream('diff.png'));35 }36 await browser.close();37})();38const { chromium } = require('playwright');39(async () => {40 const browser = await chromium.launch();41 const context = await browser.newContext();42 const page = await context.newPage();43 await page.screenshot({ path: 'example.png' });
Using AI Code Generation
1const {chromium} = require('playwright');2(async () => {3 const browser = await chromium.launch();4 const context = await browser.newContext();5 const page = await context.newPage();6 await page.screenshot({ path: 'google.png' });7 await page.close();8 await browser.close();9})();10const { pixelmatch } = require('playwright/lib/server/supplements/recorder/recorderApp');11const fs = require('fs');12const PNG = require('pngjs').PNG;13const img1 = PNG.sync.read(fs.readFileSync('google.png'));14const img2 = PNG.sync.read(fs.readFileSync('google1.png'));15const { width, height } = img1;16const diff = new PNG({ width, height });17const numDiffPixels = pixelmatch(18 { threshold: 0.1 }19);20console.log(`${numDiffPixels} different pixels`);21fs.writeFileSync('diff.png', PNG.sync.write(diff));
Using AI Code Generation
1const { chromium } = require('playwright');2(async () => {3 const browser = await chromium.launch({headless: false});4 const context = await browser.newContext();5 const page = await context.newPage();6 await page.screenshot({ path: 'example.png' });7 await page.close();8 await context.close();9 await browser.close();10})();11const { chromium } = require('playwright');12(async () => {13 const browser = await chromium.launch({headless: false});14 const context = await browser.newContext();15 const page = await context.newPage();16 await page.screenshot({ path: 'example.png' });17 await page.close();18 await context.close();19 await browser.close();20})();21const { chromium } = require('playwright');22(async () => {23 const browser = await chromium.launch({headless: false});24 const context = await browser.newContext();25 const page = await context.newPage();26 await page.screenshot({ path: 'example.png' });27 await page.close();28 await context.close();29 await browser.close();30})();31const { chromium } = require('playwright');32(async () => {33 const browser = await chromium.launch({headless: false});34 const context = await browser.newContext();35 const page = await context.newPage();36 await page.screenshot({ path: 'example.png' });37 await page.close();38 await context.close();39 await browser.close();40})();41const { chromium } = require('playwright');42(async () => {43 const browser = await chromium.launch({headless: false});44 const context = await browser.newContext();45 const page = await context.newPage();46 await page.screenshot({ path: 'example.png' });47 await page.close();48 await context.close();49 await browser.close();50})();
Using AI Code Generation
1const {chromium} = require('playwright');2const {pixelmatch} = require('playwright');3(async () => {4 const browser = await chromium.launch();5 const context = await browser.newContext();6 const page = await context.newPage();7 const image1 = await page.screenshot();8 await page.click('text=Docs');9 const image2 = await page.screenshot();10 const diff = await pixelmatch(image1, image2, 800, 600, {threshold: 0.1});11 console.log(diff);12 await browser.close();13})();
Using AI Code Generation
1const {chromium} = require('playwright');2const pixelmatch = require('playwright/lib/server/supplements/utils/pixelmatch');3(async () => {4 const browser = await chromium.launch();5 const page = await browser.newPage();6 const image = await page.screenshot();7 const screenshotBuffer = image.buffer;8 const screenshotBuffer2 = await page.screenshot().then(image => image.buffer);9 const diff = pixelmatch(screenshotBuffer, screenshotBuffer2, null, 1920, 1080, {threshold: 0.1});10 console.log(diff);11 await browser.close();12})();13What’s the output of console.log(image.buffer.length) ?
Using AI Code Generation
1import { chromium } from 'playwright';2import { pixelmatch } from 'playwright/internal';3(async () => {4 const browser = await chromium.launch();5 const page = await browser.newPage();6 await page.screenshot({ path: 'playwright.png' });7 await page.screenshot({ path: 'playwright1.png' });8 const img1 = await page.screenshot();9 const img2 = await page.screenshot();10 const diff = pixelmatch(img1, img2, null, 800, 600, { threshold: 0.1 });11 console.log({ diff });12 await browser.close();13})();14{ diff: 0 }
Using AI Code Generation
1const {chromium, devices, webkit, firefox} = require('playwright');2const {pixelmatch} = require('playwright/lib/server/supplements/recorder/recorderSupplement');3(async () => {4 const browser = await chromium.launch();5 const context = await browser.newContext();6 const page = await context.newPage();7 const page1 = await context.newPage();8 await page1.screenshot({ path: 'google.png' });9 const page2 = await context.newPage();10 await page2.screenshot({ path: 'google1.png' });11 const img1 = await page1.screenshot();12 const img2 = await page2.screenshot();13 const diff = await pixelmatch(img1, img2, 1280, 720, {threshold: 0.1});14 console.log(diff);15 await browser.close();16})();17const {chromium, devices, webkit, firefox} = require('playwright');18const {pixelmatch} = require('playwright/lib/server/supplements/recorder/recorderSupplement');19(async () => {20 const browser = await chromium.launch();21 const context = await browser.newContext();22 const page = await context.newPage();23 const page1 = await context.newPage();24 await page1.screenshot({ path: 'google.png' });25 const page2 = await context.newPage();26 await page2.screenshot({ path: 'google1.png' });27 const img1 = await page1.screenshot();28 const img2 = await page2.screenshot();29 const diff = await pixelmatch(img1, img2, 1280, 720, {threshold: 0.1});30 console.log(diff);31 await browser.close();32})();33const {chromium, devices, webkit, firefox} = require('playwright');34const {pixelmatch} = require('playwright/lib/server/supplements/recorder/recorderSupplement');35(async () => {
Using AI Code Generation
1const { pixelmatch } = require('playwright/lib/server/chromium/crPage');2const fs = require('fs');3const path = require('path');4const PNG = require('pngjs').PNG;5(async () => {6 const img1 = PNG.sync.read(fs.readFileSync(path.join(__dirname, 'img1.png')));7 const img2 = PNG.sync.read(fs.readFileSync(path.join(__dirname, 'img2.png')));8 const { width, height } = img1;9 const diff = new PNG({ width, height });10 const mismatchedPixels = pixelmatch(img1.data, img2.data, diff.data, width, height, { threshold: 0.1 });11 fs.writeFileSync(path.join(__dirname, 'diff.png'), PNG.sync.write(diff));12 console.log('Mismatched pixels:', mismatchedPixels);13})();
Using AI Code Generation
1const { chromium } = require('playwright');2const pixelmatch = require('pixelmatch');3const { PNG } = require('pngjs');4const fs = require('fs');5(async () => {6 const browser = await chromium.launch();7 const context = await browser.newContext();8 const page = await context.newPage();9 await page.screenshot({ path: 'google.png' });10 const img1 = PNG.sync.read(fs.readFileSync('google.png'));11 const img2 = PNG.sync.read(fs.readFileSync('google2.png'));12 const { width, height } = img1;13 const diff = new PNG({ width, height });14 const numDiffPixels = pixelmatch(15 { threshold: 0.1 }16 );17 fs.writeFileSync('diff.png', PNG.sync.write(diff));18 console.log(`${numDiffPixels} different pixels`);19 await browser.close();20})();
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