# @appium/opencv > OpenCV-related helper methods [![NPM version](http://img.shields.io/npm/v/@appium/opencv.svg)](https://npmjs.org/package/@appium/opencv) [![Downloads](http://img.shields.io/npm/dm/@appium/opencv.svg)](https://npmjs.org/package/@appium/opencv) ## Installation `npm install @appium/opencv` ## Usage ### initOpenCv Loads the opencv bindings. You only need to explicitly call this if you want to use your own opencv methods that are not included in this module. ```js import {initOpenCv} from '@appium/opencv'; await initOpenCv(); ``` ### getImagesMatches Calculates the count of common edges between two images. The images might be rotated or resized relatively to each other. See the function definition for more details. ```js import {getImagesMatches} from '@appium/opencv'; import {fs} from '@appium/support'; const image1 = await fs.readFile('image1.jpg') const image2 = await fs.readFile('image2.jpg') const {points1, rect1, points2, rect2, totalCount, count} = await getImagesMatches(image1, image2); ``` ### getImagesSimilarity Calculates the similarity score between two images. It is expected that both images have the same resolution. See the function definition for more details. ```js import {getImagesSimilarity} from '@appium/opencv'; import {fs} from '@appium/support'; const image1 = await fs.readFile('image1.jpg') const image2 = await fs.readFile('image2.jpg') const {score} = await getImagesSimilarity(image1, image2); ``` ### getImageOccurrence Calculates the occurrence position of a partial image in the full image. See the function definition for more details. ```js import {getImageOccurrence} from '@appium/opencv'; import {fs} from '@appium/support'; const fullImage = await fs.readFile('image1.jpg') const partialImage = await fs.readFile('image2.jpg') const {rect, score} = await getImageOccurrence(fullImage, partialImage); ``` ## License Apache-2.0