  Multimodal emotion recognition identifies human emotions from various data
modalities like video, text, and audio. However, we found that this task can be
easily affected by noisy information that does not contain useful semantics. To
this end, we present a novel paradigm that attempts to extract noise-resistant
features in its pipeline and introduces a noise-aware learning scheme to
effectively improve the robustness of multimodal emotion understanding. Our new
pipeline, namely Noise-Resistant Multimodal Transformer (NORM-TR), mainly
introduces a Noise-Resistant Generic Feature (NRGF) extractor and a Transformer
for the multimodal emotion recognition task. In particular, we make the NRGF
extractor learn a generic and disturbance-insensitive representation so that
consistent and meaningful semantics can be obtained. Furthermore, we apply a
Transformer to incorporate Multimodal Features (MFs) of multimodal inputs based
on their relations to the NRGF. Therefore, the possible insensitive but useful
information of NRGF could be complemented by MFs that contain more details. To
train the NORM-TR properly, our proposed noise-aware learning scheme
complements normal emotion recognition losses by enhancing the learning against
noises. Our learning scheme explicitly adds noises to either all the modalities
or a specific modality at random locations of a multimodal input sequence. We
correspondingly introduce two adversarial losses to encourage the NRGF
extractor to learn to extract the NRGFs invariant to the added noises, thus
facilitating the NORM-TR to achieve more favorable multimodal emotion
recognition performance. In practice, on several popular multimodal datasets,
our NORM-TR achieves state-of-the-art performance and outperforms existing
methods by a large margin, which demonstrates that the ability to resist noisy
information is important for effective emotion recognition.
