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Volume 42 - Numéro spécial CRI 2023 - 2024
Le Colloque de Recherche en Informatique est la plus importance conférence scientifique en Informatique au Cameroun depuis sa création en 2013. Il regroupe tous les deux ans plus de deux cents chercheurs, enseignants-chercheurs et professionnels de l’Informatique au Cameroun pour discuter des enjeux, défis, opportunités, risques et présenter les innovations et résultats scientifiques dans ce domaine. La sixième édition du Colloque de Recherche en Informatique CRI’2023 (http://cri-info.cm) s’est tenu les 12 et 13 décembre 2023 au Département d’Informatique de la Faculté des Sciences de l’Université de Yaoundé I en traitant les problématiques d’apprentissage artificielle, de fouille de données, d’optimisation combinatoire et du traitement automatique du langage naturel et de la parole.
1. Deux Schémas de Stéganographie Textuelles basés sur le codage des couleurs.
Text steganography is a mechanism of hiding secret text message inside another text as a covering message. In this paper, we propose a text steganographic scheme based on color coding. This includes two different methods: the first based on permutation, and the second based on numeration systems. Given a secret message and a cover text, the proposed schemes embed the secret message in the cover text by making it colored. The stego-text is then send to the receiver by mail. After experiments, the results obtained show that our models perform a better hiding process in terms of hiding capacity as compared to the scheme of Aruna Malik et al. on which our idea is based.
2. Analyse des toux COVID-19 : De la forme la plus légère à la plus sévère, une classification réaliste par apprentissage profond
Cough is the most common symptom of lung disease. COVID-19, a respiratory illness, has caused over 700 million positive cases and 7 million deaths worldwide. An effective, affordable, and widely available diagnostic tool is crucial in combating lung disease and the COVID-19 pandemic. Deep learning and machine learning algorithms could be used to analyze the cough sounds of infected patients and make predictions. Our research lab and the COUGHVID research lab provide the cough data. This diagnostic approach can distinguish cough sounds from COVID-19 patients and people suffering from other ailments as well as healthy people using deep learning and feature extraction from Mel spectrograms. The model used is a variant of ConvNet. This ConvNet model can easily capture features in MFCC Vectors and enable convolution parallelism, which increases processing speed. ConvNet attains translational invariance in features through the sharing of weights between layers. During data acquisition for model training, it is important to consider quiet environments to reduce errors in audio quality. The architecture of the convolutional neural networks gives an F1-score of 89%, an accuracy of 90.33% and sensitivity of 87.3%. This system has the potential to significantly impact society by reducing virus transmission, expediting patient treatment, and freeing up hospital resources. Early detection of COVID-19 can prevent disease progression and enhance screening effectiveness.
3. Application du modèle de représentation acoustique multilingue XLSR pour la transcription de l'Ewondo
Recently popularized self-supervised models appear as a solution to the problem of low data availability via parsimonious learning transfer. We investigate the effectiveness of these multilingual acoustic models, in this case wav2vec 2.0 XLSR-53 and wav2vec 2.0 XLSR-128, for the transcription task of the Ewondo language (spoken in Cameroon). The experiments were conducted on 11 minutes of speech constructed from 103 read sentences. Despite a strong generalization capacity of multilingual acoustic model, preliminary results show that the distance between XLSR embedded languages (English, French, Spanish, German, Mandarin, . . . ) and Ewondo strongly impacts the performance of the transcription model. The highest performances obtained are around 69% on the WER and 28.1% on the CER. An analysis of these preliminary results is carried out andthen interpreted; in order to ultimately propose effective ways of improvement.