Visual Testing

What is Visual Testing?

Visual Testing is performed on the user interface so as to make sure the interface is sustaining all the visual specifications provided by the client as a part of the functional or non-functional specification. Furthermore, as it is an established fact that it is important for testing the functionality of any application for maintaining the quality of the product, it is equally important for a product to have a friendly and catchy user interface in order to engage and ease the end-users who are supposed to be accessing the application product.

Why do We Need Visual Testing?

No matter how efficiently and accurately the functionality of an application is working, it is not worthy if the UI of the application is not good. Many big companies including Google, Adobe, Yahoo, Twitter hire a special team of testers for the Visual testing of an application because they understand the importance of Visual testing and how it could adversely affect their business it is not properly visually tested.

Some of the reasons depicting the importance of Visual testing in the real world are given below:

• Poor UI or look of any software application can cause inconvenience to the customers in using it and hence can affect the company’s image in the market.
• Difficulty in using the application on different browsers can affect the customers which can cause the loss of clients and hence impacting the overall revenue of the company.
• Due to a large number of Operating Systems and devices with different screen sizes available in the market, it is important that the application is responsive enough to run according to the different screen sizes and Operating Systems.
• The first impression of the customer regarding the software product is from the UI and the ease of using the application, if it is not so or the customer had a bad experience using it, the customer will not think of using it further even if the functionality is working proficient and all the money invested in the software is next to waste.

How does Visual Testing Work and its Techniques?

It can be performed either manually or through automated tools. In manual Visual testing, manual testers are deployed finding the issues in using the application on various devices, screen sizes, Operating Systems, and different browsers. In manual testing, it is more like a spot- a- difference using the snapshots or the manuals provided by the developers. UI of the application with various components sizes, color, style is tested. Application UI is also tested with network changes.

As it is impossible to detect the minor UI changes through manual Visual testing, automated Visual testing came into existence to have speedy work as the application can be tested concurrently across various screens and browsers concurrently. Automated Visual testing allows us to validate the various components of web applications and focuses on the correctness of the content being positioned in the layout of web pages. It checks the positioning of the elements in a web page as well as the other factors like overlapping of text, hiding elements color, size, shape, etc.

There are various tools available in the market which helps in the automated visual testing of an application. Some of them are given below:

1. Selenium
2. Watir
3. WebdriverCSS
4. Gemini
5. Storybook

The main difference between manual visual testing and automated one is that manual testing is very time-consuming as it takes time to perform testing on various devices and browsers. Moreover, it is impossible for the human eye to test the application pixel by pixel. Though automation testing resolves this problem of accuracy and testing the application with minor changes automated tests requires the high maintenance of baseline test of expected images for various screens, resolutions, Operating system and browsers. Sometimes unnecessary bugs arise if we compare every component pixel by pixel which leads to the continuous failure of test cases without any major issue. So it is necessary to understand how much the visual part of the application should be automated for effective results.

Advantages & Disadvantages of Visual testing

Below are the advantages and disadvantages explained.

Advantages

1. Regressive Visual testing around the application causes fewer problems while using the application creates a good impression on the client about the software product and allows them to use it further.
2. It is as important as the functional testing of an application. The functionality of an application does not matter if the UI is not good enough allowing the user to use it and perform desired tasks.
3. Good UI of the application attracts customers and hence helps in increasing the overall product revenue.
4. Automated visual testing across various browsers concurrently reduces the time invested executing each test case on one browser at a time.
5. Visual tests on every commit reduce the chances of failure of an application and give the confidence that every single change in UI is working fine in a production environment.

Disadvantages

1. Practically, it is not possible to test any software application on various screens with different resolutions. There are some bugs that are resolution specific, they remain untested even after rigorous Visual testing.
2. Minor UI issues that the human eye is unable to identify remain unnoticed during the Visual test of an application. Only the larger bugs are identified in Visual testing.
3. There are high chances of inconsistencies in finding the bugs among different testers.
4. In this, the bugs also depend on various factors like time, network, device, etc. Some bugs are filed due to network issues and unnecessary time is wasted on fixing them which are working fine in a real environment.
5. Automated Visual testing requires a lot of maintenance and hence it is not worthy to implement in small projects.

Conclusion

The above description clearly explains what is Visual testing and its importance in the real IT world. It plays a very important role in the Software testing domain as it is all the UI of the application that first creates an impression on customers and encourages them to use it. Big IT companies hire professional testers for the same as it can largely affect their business. Nowadays, automated Visual testing has largely replaced manual testing as it can perform testing with speed (which in turn saves time) and is able to detect small UI changes.

Recommended Articles

This is a guide to Visual Testing. Here we discuss how does it works and its techniques? along with advantages and disadvantages. You may also look at the following articles to learn more –

1. Functional Testing Tools
2. What is ETL Testing?
3. Automation Testing Life Cycle
4. Manual Testing vs Automation Testing