Heyfa Ammar - Academia.edu (original) (raw)
Papers by Heyfa Ammar
Journal of King Saud University - Computer and Information Sciences
2021 IEEE Asia-Pacific Conference on Computer Science and Data Engineering (CSDE), 2021
Publication in the conference proceedings of EUSIPCO, Barcelona, Spain, 2011
Due to the rapidly increasing number of requests from the surveillance and security industries, d... more Due to the rapidly increasing number of requests from the surveillance and security industries, detecting a panic behavior in human crowd have become an active research in the field of computer vision in recent years. The automatic and real-time analysis of video sequences in order to detect a panic behavior is one of the most challenging tasks for computer vision experts. This stems from the fact that a panic is mostly defined as a sudden change in the pedestrian movements and that motion estimation is computationally expensive. The aim of this paper is to give an overview of the reported real-time techniques in the literature by focusing on how these techniques overcame the heavy computations of the motion estimation. Moreover, the present work summarizes the accuracy and the execution time of those techniques to highlight the direction to future studies.
International Journal of Advanced Computer Science and Applications, 2017
Quadriplegic people are unable to use mobile devices without the aid of other persons which can b... more Quadriplegic people are unable to use mobile devices without the aid of other persons which can be devastating for them both socially and economically. This has motivated many researchers to propose hardware and software solutions that operate as intermediates between the impaired users and their devices: accessibility switches, joysticks and head movements. However, the efficiency of these tools is limited in some conditions. To alleviate this problem, we propose to exploit electroencephalographic signals captured via an adequate headset. More precisely, the user is asked to perform a facial expression that will be recognized by the system through the analysis of the EEG signals. Several facial expressions are offered and each one corresponds to a command wirelessly sent to the mobile device and executed. This Brain Computer Interface based system is called SmileToPhone. It enables the quadriplegic patients to use their smartphones in an easy way with a minimum of effort and with respect to studied Human-Computer-Interaction requirements. The system includes the main functionalities of a smartphone such as making calls and sending messages. The evaluation of the system usability showed that most of the time, users were able to use the different functionalities of the system in an easy way. The current results are encouraging and motivating to add more features to the system.
Publication in the conference proceedings of EUSIPCO, Marrakech, Morocco, 2013
2019 11th International Conference on Knowledge and Systems Engineering (KSE), 2019
One of important issue needs attention in the area of old film storage and restoration is blotch ... more One of important issue needs attention in the area of old film storage and restoration is blotch handling. In this work, a new proposal including an automatic detection method and inpainting scheme is introduced. First, a technique for automatically detecting blotches based on local changes of pixels on consecutive frames is applied. Specifically, a two-stage Simplified Ranked Order Difference detector is proposed to identify blotches on frames. Next, an improved inpainting was applied to restore the blotches so that it is undetectable by viewers. Our proposal is executed automatically without extenal parameters. The proposal has been tested on a serial of natural images with different sizes and resolutions. Experimental results show that our approach has successfully removed with fairly high accuracy and quite smooth restored blotches. Based on result analysis, the proposal has many potential and applications in the future. Index Terms—blotch detection, blotch removal, restoration,...
Old movies suffer from several degradations mainly due to the archiving conditions. Since most of... more Old movies suffer from several degradations mainly due to the archiving conditions. Since most of the old films represent an important amount of valuable data in scientific, cultural, social and economical purposes, it is mandatory to preserve them by resorting to fully digital and ...
This paper presents a novel technique to detect obstructive sleep apnea episodes in infrared vide... more This paper presents a novel technique to detect obstructive sleep apnea episodes in infrared video recordings. The major advantage of the proposed approach is that it does not require any manual adjustments and does not depend on the patient pose. Our contribution is threefold. First, the detection of the breathing movement is based on a robust estimation of the optical flow. Second, we resort to the use of the summed motion magnitudes as an important feature allowing to distinguish between normal breathing episodes and obstructive sleep apnea episodes. Third, the motion magnitudes during apnea events are considered as having atypical values relatively to those obtained during a normal breathing and are detected thanks to the use of a statistical test for outliers detection. The experimental evaluation on real videos show high performances of the proposed technique.
I/V Communications and …, 2010
Heyfa Ammar-Badri Unité de Recherche en Imagerie Satellitaire et ses Applications (URISA) Ecole S... more Heyfa Ammar-Badri Unité de Recherche en Imagerie Satellitaire et ses Applications (URISA) Ecole Supérieure des Communications de Tunis Cité des Communications El Ghazala 2083, Ariana, Tunisia Email: heyfa.ammar@supcom.rnu.tn ... Amel Benazza-Benyahia ...
Machine Vision and Applications
Multimedia Tools and Applications
Machine Vision and Applications
International Journal of Advanced Computer Science and Applications
The objective assessment of the vocal fold vibrations is important in diagnosing several vocal di... more The objective assessment of the vocal fold vibrations is important in diagnosing several vocal diseases. Given the high speed of the vibrations, the high speed videoendoscopy is commonly used to capture the vocal fold movements into video recordings. Commonly, two steps are carried out in order to automatically quantify laryngeal parameters and assess the vibrations. The first step aims to map the spatial-temporal information contained in the video recordings into a representation that facilitates the analysis of the vibrations. Numerous techniques are reported in the literature but the majority of them require the segmentation of all the images of the video, which is a complex task. The second step aims to quantify laryngeal parameters in order to assess the vibrations. To this aim, most of the existing approaches require an additional processing to the representation in order to deduce those parameters. Furthermore, for some reported representations, the assessment of the symmetry and the periodicity of the vocal fold dynamics needs setting up parameters that are specific to the representation under consideration; which makes difficult the comparison between the existing techniques. To alleviate these problems, the present study investigates the use of a recently proposed representation named optical flow based waveform, in order to objectively quantify the laryngeal parameters. This waveform is retained in this study as it does not require the segmentation of all the images of the video. Furthermore, it will be shown in the present work that the automatic quantification of the vibrations using this waveform can be carried out without applying any additional processing. Moreover, common laryngeal parameters are exploited; hence, no specific parameters are needed to be defined for the automatic assessment of the vibrations. Experiments conducted on healthy and pathological phonation show the accuracy of the waveform. Besides, it is more sensitive to pathological phonation than the state-of-the-art techniques.
Australasian Physical & Engineering Sciences in Medicine
Machine Vision and Applications
Journal of King Saud University - Computer and Information Sciences
2021 IEEE Asia-Pacific Conference on Computer Science and Data Engineering (CSDE), 2021
Publication in the conference proceedings of EUSIPCO, Barcelona, Spain, 2011
Due to the rapidly increasing number of requests from the surveillance and security industries, d... more Due to the rapidly increasing number of requests from the surveillance and security industries, detecting a panic behavior in human crowd have become an active research in the field of computer vision in recent years. The automatic and real-time analysis of video sequences in order to detect a panic behavior is one of the most challenging tasks for computer vision experts. This stems from the fact that a panic is mostly defined as a sudden change in the pedestrian movements and that motion estimation is computationally expensive. The aim of this paper is to give an overview of the reported real-time techniques in the literature by focusing on how these techniques overcame the heavy computations of the motion estimation. Moreover, the present work summarizes the accuracy and the execution time of those techniques to highlight the direction to future studies.
International Journal of Advanced Computer Science and Applications, 2017
Quadriplegic people are unable to use mobile devices without the aid of other persons which can b... more Quadriplegic people are unable to use mobile devices without the aid of other persons which can be devastating for them both socially and economically. This has motivated many researchers to propose hardware and software solutions that operate as intermediates between the impaired users and their devices: accessibility switches, joysticks and head movements. However, the efficiency of these tools is limited in some conditions. To alleviate this problem, we propose to exploit electroencephalographic signals captured via an adequate headset. More precisely, the user is asked to perform a facial expression that will be recognized by the system through the analysis of the EEG signals. Several facial expressions are offered and each one corresponds to a command wirelessly sent to the mobile device and executed. This Brain Computer Interface based system is called SmileToPhone. It enables the quadriplegic patients to use their smartphones in an easy way with a minimum of effort and with respect to studied Human-Computer-Interaction requirements. The system includes the main functionalities of a smartphone such as making calls and sending messages. The evaluation of the system usability showed that most of the time, users were able to use the different functionalities of the system in an easy way. The current results are encouraging and motivating to add more features to the system.
Publication in the conference proceedings of EUSIPCO, Marrakech, Morocco, 2013
2019 11th International Conference on Knowledge and Systems Engineering (KSE), 2019
One of important issue needs attention in the area of old film storage and restoration is blotch ... more One of important issue needs attention in the area of old film storage and restoration is blotch handling. In this work, a new proposal including an automatic detection method and inpainting scheme is introduced. First, a technique for automatically detecting blotches based on local changes of pixels on consecutive frames is applied. Specifically, a two-stage Simplified Ranked Order Difference detector is proposed to identify blotches on frames. Next, an improved inpainting was applied to restore the blotches so that it is undetectable by viewers. Our proposal is executed automatically without extenal parameters. The proposal has been tested on a serial of natural images with different sizes and resolutions. Experimental results show that our approach has successfully removed with fairly high accuracy and quite smooth restored blotches. Based on result analysis, the proposal has many potential and applications in the future. Index Terms—blotch detection, blotch removal, restoration,...
Old movies suffer from several degradations mainly due to the archiving conditions. Since most of... more Old movies suffer from several degradations mainly due to the archiving conditions. Since most of the old films represent an important amount of valuable data in scientific, cultural, social and economical purposes, it is mandatory to preserve them by resorting to fully digital and ...
This paper presents a novel technique to detect obstructive sleep apnea episodes in infrared vide... more This paper presents a novel technique to detect obstructive sleep apnea episodes in infrared video recordings. The major advantage of the proposed approach is that it does not require any manual adjustments and does not depend on the patient pose. Our contribution is threefold. First, the detection of the breathing movement is based on a robust estimation of the optical flow. Second, we resort to the use of the summed motion magnitudes as an important feature allowing to distinguish between normal breathing episodes and obstructive sleep apnea episodes. Third, the motion magnitudes during apnea events are considered as having atypical values relatively to those obtained during a normal breathing and are detected thanks to the use of a statistical test for outliers detection. The experimental evaluation on real videos show high performances of the proposed technique.
I/V Communications and …, 2010
Heyfa Ammar-Badri Unité de Recherche en Imagerie Satellitaire et ses Applications (URISA) Ecole S... more Heyfa Ammar-Badri Unité de Recherche en Imagerie Satellitaire et ses Applications (URISA) Ecole Supérieure des Communications de Tunis Cité des Communications El Ghazala 2083, Ariana, Tunisia Email: heyfa.ammar@supcom.rnu.tn ... Amel Benazza-Benyahia ...
Machine Vision and Applications
Multimedia Tools and Applications
Machine Vision and Applications
International Journal of Advanced Computer Science and Applications
The objective assessment of the vocal fold vibrations is important in diagnosing several vocal di... more The objective assessment of the vocal fold vibrations is important in diagnosing several vocal diseases. Given the high speed of the vibrations, the high speed videoendoscopy is commonly used to capture the vocal fold movements into video recordings. Commonly, two steps are carried out in order to automatically quantify laryngeal parameters and assess the vibrations. The first step aims to map the spatial-temporal information contained in the video recordings into a representation that facilitates the analysis of the vibrations. Numerous techniques are reported in the literature but the majority of them require the segmentation of all the images of the video, which is a complex task. The second step aims to quantify laryngeal parameters in order to assess the vibrations. To this aim, most of the existing approaches require an additional processing to the representation in order to deduce those parameters. Furthermore, for some reported representations, the assessment of the symmetry and the periodicity of the vocal fold dynamics needs setting up parameters that are specific to the representation under consideration; which makes difficult the comparison between the existing techniques. To alleviate these problems, the present study investigates the use of a recently proposed representation named optical flow based waveform, in order to objectively quantify the laryngeal parameters. This waveform is retained in this study as it does not require the segmentation of all the images of the video. Furthermore, it will be shown in the present work that the automatic quantification of the vibrations using this waveform can be carried out without applying any additional processing. Moreover, common laryngeal parameters are exploited; hence, no specific parameters are needed to be defined for the automatic assessment of the vibrations. Experiments conducted on healthy and pathological phonation show the accuracy of the waveform. Besides, it is more sensitive to pathological phonation than the state-of-the-art techniques.
Australasian Physical & Engineering Sciences in Medicine
Machine Vision and Applications