Twitter removed image cropping on iOS, Android apps because it’s biased
Twitter has removed its automated image cropping on Android and iOS apps and has allowed for larger image previews. The algorithmic image cropping that Twitter was using to fit images into preview boxes was problematic on many levels, including being biased on racial and gender grounds.
The platform conducted research of its image-cropping algorithm after many users pointed out that the Twitter algorithm was choosing white people over black ones and males over females in photo crops. The study, titled Image Cropping on Twitter: Fairness Metrics, their Limitations, and the Importance of Representation, Design, and Agency, was conducted by Kyra Yee, Uthaipon Tantipongpipat, and Shubhanshu Mishra. You can check it out here.
The study found that in photo-crop comparisons between black and white individuals there was a 7% difference in favour of white individuals. There is also a 7% difference in parity in favour of white women over black. When comparing white and black men, there was a 2% difference in favour of white men and an overall 4% preference for white individuals. And while comparing men and women in general, there was an 8% difference in favour of women.
The study also tested for gender bias to see if the algorithm chose to crop men more than women and if the cropped pictures of women were done inappropriately (was the photo being cropped around a woman's chest or legs instead of the face). While the algorithm favours women 8% of the time, the cropping was inappropriate in most cases. About 3% of the cases where the woman's face was not cropped, the preview focused on things like the sports jersey number.
Twitter removed the automatic image cropping in May and allowed users to post photos in its entirety, or decide for themselves how they wanted to crop it. "One of our conclusions is that not everything on Twitter is a good candidate for an algorithm, and in this case, how to crop an image is a decision best made by people," Rumman Chowdhury, Twitter's director of software engineering, explained in a blog post about the team's findings.
Twitter has been using the algorithm to crop images to make them fit into image preview boxes since 2018. The algorithm works on trying to determine what will be most visually interesting to a user and includes that part in the preview. Besides this study, the social media platform has also admitted that the algorithm could still be harmful in many other ways it hasn't tested yet and that relying on machine learning to crop images takes away agency from users.
For now, iOS and Android apps have bigger images previews so as the algorithm does not need to make “as many cropping decisions” and if the image is far too wide or too tall and needs to be cropped, the user will be shown a preview of what it will look like. However, this cropping algorithm is not gone entirely though, Twitter on web still uses it.