Dear MultiMediate participants,

we are delighted to share with you that MultiMediate was accepted as an ACM Multimedia Grand Challenge for 2025. We present a concise overview over MultiMediate’25 below and follow up with additional information in the days and weeks.

Estimating the momentary level of engagement from multi-modal participant behaviour is an important prerequisite for assistive systems that support human interactions. At the same time, the connection between engagement and behaviour heavily depends on situational and cultural characteristics. Therefore, MultiMediate’25 poses the cross-cultural, multi-domain engagement estimation challenge. The challenge covers a unique combination of training and test data from diverse cultural backgrounds, including Japanese, Chinese, German, Arabic, Indonesian, and French speakers, as well as different interaction situations (group vs. dyadic). In addition to evaluation metrics that quantify the overall quality of predictions, MultiMediate’25 will also quantify the amount of bias in predictions with respect to the variables gender and cultural background. In addition to engagement estimation, we continue to invite submissions to popular tasks from previous iterations of the challenge: eye contact detection, bodily behaviour recognition, backchannel detection. For teams participating in the bodily behaviour recognition challenge, we encourage to also evaluate their approaches on this year’s Micro-Action Analysis Challenge (https://sites.google.com/view/micro-action).

While most datasets used in the challenge are ready for download now, we are currently preparing updated feature representations for the engagement estimation datasets. In contrast to last year, we will also publish the raw videos such that participants are able to extract their own features or train end-to-end approaches.

In case of any questions, please let us know!

Best,

Philipp