Speech Emotion Recognition Model Based on Joint Modeling of Discrete and Dimensional Emotion Representation

This paper introduces a novel joint model architecture for Speech Emotion Recognition (SER) that integrates both discrete and dimensional emotional representations, allowing for the simultaneous training of classification and regression tasks to improve the comprehensiveness and interpretability of...

Full description

Saved in:
Bibliographic Details
Main Authors: John Lorenzo Bautista, Hyun Soon Shin
Format: Article
Language:English
Published: MDPI AG 2025-01-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/15/2/623
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832589239596875776
author John Lorenzo Bautista
Hyun Soon Shin
author_facet John Lorenzo Bautista
Hyun Soon Shin
author_sort John Lorenzo Bautista
collection DOAJ
description This paper introduces a novel joint model architecture for Speech Emotion Recognition (SER) that integrates both discrete and dimensional emotional representations, allowing for the simultaneous training of classification and regression tasks to improve the comprehensiveness and interpretability of emotion recognition. By employing a joint loss function that combines categorical and regression losses, the model ensures balanced optimization across tasks, with experiments exploring various weighting schemes using a tunable parameter to adjust task importance. Two adaptive weight balancing schemes, Dynamic Weighting and Joint Weighting, further enhance performance by dynamically adjusting task weights based on optimization progress and ensuring balanced emotion representation during backpropagation. The architecture employs parallel feature extraction through independent encoders, designed to capture unique features from multiple modalities, including Mel-frequency Cepstral Coefficients (MFCC), Short-term Features (STF), Mel-spectrograms, and raw audio signals. Additionally, pre-trained models such as Wav2Vec 2.0 and HuBERT are integrated to leverage their robust latent features. The inclusion of self-attention and co-attention mechanisms allows the model to capture relationships between input modalities and interdependencies among features, further improving its interpretability and integration capabilities. Experiments conducted on the IEMOCAP dataset using a leave-one-subject-out approach demonstrate the model’s effectiveness, with results showing a 1–2% accuracy improvement over classification-only models. The optimal configuration, incorporating the joint architecture, dynamic weighting, and parallel processing of multimodal features, achieves a weighted accuracy of 72.66%, an unweighted accuracy of 73.22%, and a mean Concordance Correlation Coefficient (CCC) of 0.3717. These results validate the effectiveness of the proposed joint model architecture and adaptive balancing weight schemes in improving SER performance.
format Article
id doaj-art-1b8092cbc7894ace96d46848266b4ea5
institution Kabale University
issn 2076-3417
language English
publishDate 2025-01-01
publisher MDPI AG
record_format Article
series Applied Sciences
spelling doaj-art-1b8092cbc7894ace96d46848266b4ea52025-01-24T13:20:09ZengMDPI AGApplied Sciences2076-34172025-01-0115262310.3390/app15020623Speech Emotion Recognition Model Based on Joint Modeling of Discrete and Dimensional Emotion RepresentationJohn Lorenzo Bautista0Hyun Soon Shin1Emotion Recognition IoT Research Section, Hyper-Connected Communication Research Laboratory, Electronic and Telecommunications Research Institute (ETRI), Daejeon 34129, Republic of KoreaEmotion Recognition IoT Research Section, Hyper-Connected Communication Research Laboratory, Electronic and Telecommunications Research Institute (ETRI), Daejeon 34129, Republic of KoreaThis paper introduces a novel joint model architecture for Speech Emotion Recognition (SER) that integrates both discrete and dimensional emotional representations, allowing for the simultaneous training of classification and regression tasks to improve the comprehensiveness and interpretability of emotion recognition. By employing a joint loss function that combines categorical and regression losses, the model ensures balanced optimization across tasks, with experiments exploring various weighting schemes using a tunable parameter to adjust task importance. Two adaptive weight balancing schemes, Dynamic Weighting and Joint Weighting, further enhance performance by dynamically adjusting task weights based on optimization progress and ensuring balanced emotion representation during backpropagation. The architecture employs parallel feature extraction through independent encoders, designed to capture unique features from multiple modalities, including Mel-frequency Cepstral Coefficients (MFCC), Short-term Features (STF), Mel-spectrograms, and raw audio signals. Additionally, pre-trained models such as Wav2Vec 2.0 and HuBERT are integrated to leverage their robust latent features. The inclusion of self-attention and co-attention mechanisms allows the model to capture relationships between input modalities and interdependencies among features, further improving its interpretability and integration capabilities. Experiments conducted on the IEMOCAP dataset using a leave-one-subject-out approach demonstrate the model’s effectiveness, with results showing a 1–2% accuracy improvement over classification-only models. The optimal configuration, incorporating the joint architecture, dynamic weighting, and parallel processing of multimodal features, achieves a weighted accuracy of 72.66%, an unweighted accuracy of 73.22%, and a mean Concordance Correlation Coefficient (CCC) of 0.3717. These results validate the effectiveness of the proposed joint model architecture and adaptive balancing weight schemes in improving SER performance.https://www.mdpi.com/2076-3417/15/2/623adaptive weight balancing schemeaffective computingdimensional emotion representationdiscrete emotion representationjoint model architectureSpeech Emotion Recognition (SER)
spellingShingle John Lorenzo Bautista
Hyun Soon Shin
Speech Emotion Recognition Model Based on Joint Modeling of Discrete and Dimensional Emotion Representation
Applied Sciences
adaptive weight balancing scheme
affective computing
dimensional emotion representation
discrete emotion representation
joint model architecture
Speech Emotion Recognition (SER)
title Speech Emotion Recognition Model Based on Joint Modeling of Discrete and Dimensional Emotion Representation
title_full Speech Emotion Recognition Model Based on Joint Modeling of Discrete and Dimensional Emotion Representation
title_fullStr Speech Emotion Recognition Model Based on Joint Modeling of Discrete and Dimensional Emotion Representation
title_full_unstemmed Speech Emotion Recognition Model Based on Joint Modeling of Discrete and Dimensional Emotion Representation
title_short Speech Emotion Recognition Model Based on Joint Modeling of Discrete and Dimensional Emotion Representation
title_sort speech emotion recognition model based on joint modeling of discrete and dimensional emotion representation
topic adaptive weight balancing scheme
affective computing
dimensional emotion representation
discrete emotion representation
joint model architecture
Speech Emotion Recognition (SER)
url https://www.mdpi.com/2076-3417/15/2/623
work_keys_str_mv AT johnlorenzobautista speechemotionrecognitionmodelbasedonjointmodelingofdiscreteanddimensionalemotionrepresentation
AT hyunsoonshin speechemotionrecognitionmodelbasedonjointmodelingofdiscreteanddimensionalemotionrepresentation