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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