Why is it necessary to use consistent image formats in visual testing?

Using consistent image formats in visual testing is crucial for ensuring there are no discrepancies in application rendering. When images are in different formats, it can lead to variations in how they are displayed across different devices and browsers, which might affect the visual integrity of the application being tested. Differences in format can influence factors like image quality, compression methods, and color representation, potentially leading to inconsistencies in the visual presentation.

By standardizing image formats, teams can control for these variables and create a reliable basis for comparison during visual regression testing. This consistency aids in identifying genuine visual changes resulting from code updates or application modifications rather than discrepancies arising from inconsistent image handling. Additionally, it streamlines the testing process since the images will render reliably, ensuring that development teams can focus on identifying and resolving actual issues rather than debugging rendering quirks related to image formats.