XUtils

image-comparison

Library that compares 2 images with the same sizes and shows the differences visually by drawing rectangles. Some parts of the image can be excluded from the comparison.

Java
https://github.com/romankh3/image-comparison

Configuration

All these configurations can be updated based on your needs.

Property Description
threshold The threshold which means the max distance between non-equal pixels. Could be changed according size and requirements to the image.
rectangleLineWidth Width of the line that is drawn the rectangle.
destination File of the result destination.
minimalRectangleSize The number of the minimal rectangle size. Count as (width x height). By default it’s 1.
maximalRectangleCount Maximal count of the Rectangles, which would be drawn. It means that would get first x biggest rectangles. Default value is -1, that means that all the rectangles would be drawn.
pixelToleranceLevel Level of the pixel tolerance. By default it’s 0.1 -> 10% difference. The value can be set from 0.0 to 0.99.
excludedAreas ExcludedAreas contains a List of Rectangles to be ignored when comparing images.
drawExcludedRectangles Flag which says draw excluded rectangles or not.
fillExcludedRectangles Flag which says fill excluded rectangles or not.
percentOpacityExcludedRectangles The desired opacity of the excluded rectangle fill.
fillDifferenceRectangles Flag which says fill difference rectangles or not.
percentOpacityDifferenceRectangles The desired opacity of the difference rectangle fill.
allowingPercentOfDifferentPixels The percent of the allowing pixels to be different to stay MATCH for comparison. E.g. percent of the pixels, which would ignore in comparison. Value can be from 0.0 to 100.00
differenceRectangleColor Rectangle color of image difference. By default, it’s red.
excludedRectangleColor Rectangle color of excluded part. By default, it’s green.

Release Notes

Can be found in RELEASE_NOTES.

Maven

<dependency>
    <groupId>com.github.romankh3</groupId>
    <artifactId>image-comparison</artifactId>
    <version>4.4.0</version>
</dependency>

Gradle

compile 'com.github.romankh3:image-comparison:4.4.0'

To compare two images programmatically

Default way to compare two images looks like:
        //load images to be compared:
        BufferedImage expectedImage = ImageComparisonUtil.readImageFromResources("expected.png");
        BufferedImage actualImage = ImageComparisonUtil.readImageFromResources("actual.png");

        //Create ImageComparison object and compare the images.
        ImageComparisonResult imageComparisonResult = new ImageComparison(expectedImage, actualImage).compareImages();
        
        //Check the result
        assertEquals(ImageComparisonState.MATCH, imageComparisonResult.getImageComparisonState());
Save result image

To save result image, can be used two ways:

  1. add a file to save to constructor. ImageComparison will save the result image in this case.
        //load images to be compared:
        BufferedImage expectedImage = ImageComparisonUtil.readImageFromResources("expected.png");
        BufferedImage actualImage = ImageComparisonUtil.readImageFromResources("actual.png");
        
        // where to save the result (leave null if you want to see the result in the UI)
        File resultDestination = new File( "result.png" );

        //Create ImageComparison object with result destination and compare the images.
        ImageComparisonResult imageComparisonResult = new ImageComparison(expectedImage, actualImage, resultDestination).compareImages();
  1. execute ImageComparisonUtil.saveImage static method
        //load images to be compared:
        BufferedImage expectedImage = ImageComparisonUtil.readImageFromResources("expected.png");
        BufferedImage actualImage = ImageComparisonUtil.readImageFromResources("actual.png");

        //Create ImageComparison object with result destination and compare the images.
        ImageComparisonResult imageComparisonResult = new ImageComparison(expectedImage, actualImage).compareImages();

        //Image can be saved after comparison, using ImageComparisonUtil.
        ImageComparisonUtil.saveImage(resultDestination, imageComparisonResult.getResult());

Demo

Demo shows how image-comparison works.

Expected Image

expected

Actual Image

actual

Result

result

Code of Conduct

Please, follow Code of Conduct page.

Also if you’re interesting - see my other repositories

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