Doug Suh - Profile on Academia.edu (original) (raw)

Papers by Doug Suh

As the necessity of haptic technology in the metaverse area has been increasing, a number of glov... more As the necessity of haptic technology in the metaverse area has been increasing, a number of glove-shaped haptic devices have been developed and commercialized. However, current commercialized devices are highly expensive for not only developing countries but also for average individuals. Therefore, this paper sets out to present an affordable and practically usable haptic glove. The three main elements contested in this paper are Leap Motion Controller (LMC), which is used to improve and stabilize the recognition of hand tracking in Unity. Elasticity, which pertains using string-based haptic feedback wherein our Haptic Glove generates an elastic effect of a virtual object. Lastly, an EMG sensor: By connecting the EMG sensor and the Haptic Glove, this paper proposes the possibility of expanding the use of the Haptic Gloves for fine motor development and rehabilitation.

Efficient Computation Offloading in Mobile Cloud Computing for Video Streaming Over 5G

Computers, materials & continua, 2019

Performance of scalable video coding with respect to differentiated service requirements

Proceedings of SPIE, Aug 18, 2005

ABSTRACT Multimedia service can be categorized as conversational, streaming, and download service... more ABSTRACT Multimedia service can be categorized as conversational, streaming, and download services, which differ in temporal and semantic quality requirements. Performance of SVC (Scalable video coding) is analyzed in the three dimensional (spatio-temporal) frequency domain. Based on the analysis, SVC scheme can be modified to satisfy various requirements as being compliant to the international standards. Decoding without enhancement layer data results in drift phenomenon. Several drift-free techniques are analyzed.

Directional Filtering for Upsampling According to Direction Information of the Base Layer in the JVT/SVC Codec

Springer eBooks, 2006

ABSTRACT When the reconstructed image of the base layer is up-sampled for decoding the enhancemen... more ABSTRACT When the reconstructed image of the base layer is up-sampled for decoding the enhancement layer of spatial scalability, direction information derived during decoding the spatially lower layer is used. That is direction information used for Intra prediction which is used for up-sampling again. In most cases, it shows 0.1-0.5dB quality improvement in images up-sampled by using directional filtering compared to those up-sampled conventionally. The same interpolation algorithm should be used in both the encoder and decoder.

Efficient stereoscopic contents file format on the basis of ISO base media file format

Proceedings of SPIE, Feb 5, 2009

A lot of 3D contents haven been widely used for multimedia services, however, real 3D video conte... more A lot of 3D contents haven been widely used for multimedia services, however, real 3D video contents have been adopted for a limited applications such as a specially designed 3D cinema. This is because of the difficulty of capturing real 3D video contents and the limitation of display devices available in a market. However, diverse types of display devices for

IEEE Access, 2018

Recently, device-to-device (D2D)-underlaid fifth-generation (5G) cellular networks have received ... more Recently, device-to-device (D2D)-underlaid fifth-generation (5G) cellular networks have received plenty of attention because of their ability to save network resources and to reduce energy consumption. Most existing algorithms for multimedia services over D2D networks consider only the signalto-noise ratio (SNR) and ignore temporal requirements, which do not provide optimum performances. To overcome this issue, we propose a framework for a cross-layer D2D link control system, which guarantees the quality of service and improves the quality of experience (QoE) for live video streaming with different priorities and delay constraints. In this framework, we considered three techniques, including priority-based video transmission, flexible communication mode switching of user equipment, and subset-based relay assignment. According to the live video generation period, our system dynamically adjusts the ratio between cellular and D2D mode durations in each unit of the communication period for each user individually. Our proposal also considerably reduces the duration and frequency of video playback freezing by delivering at least the minimum service quality of the delivered video to the sink users even in the shadow area and therefore improves the QoE for all users while minimizing energy consumption. System-level simulation shows that the proposed algorithm outperforms other methods in terms of the average mean time to failure, average peak SNR, and average energy consumption.

IEEE Access, 2018

Heterogeneity is one of the key features that characterizes the future generation of cellular net... more Heterogeneity is one of the key features that characterizes the future generation of cellular networks, 5G and beyond. However, streaming high-quality bandwidth-hungry multimedia contents over bandwidth-constrained 5G heterogeneous networks (5G HetNets) involves various significant challenges, including long video start time, video start failures, frequent buffering and stalling, and low quality of experience (QoE). Traditional multimedia streaming technologies, however, do not pay attention to either the available network bandwidth or the interaction between content characteristics and resources. To reduce network strain and improve QoE, we propose ''Context-Aware Streaming over 5G HetNets (CASH)'' that allows us to achieve a tradeoff between content-context and network-context. The proposed CASH fundamentally works in a multi-step process. First, the CASH comes with an integrated architecture that includes a media server, a flow scheduler, and a single radio controller (SRC). The SRC and the user equipment (UE) of interest cooperatively prepare a metadata file that contains the network-context. Second, based on the metadata file, which can be accessed from the SRC in the media preparation server, we analyze and cluster the contents based on the content-context, e.g., the actual bitrate of each scene. The metadata file is then updated by adding the content-context information. Third, the flow scheduler basically controls the flow of the clusters of the contents in the server-push mode and conveys that to the appropriate radio access technology (RAT) conforming to the bitrate of the clusters and bandwidth delivered by RATs. Finally, the UE will aggregate the received packets and will play-back the content. We analytically show the validity of CASH. Also, extensive simulations are performed to demonstrate that CASH offers substantial performance improvements compared with exiting works in terms of peak data rate, latency, users' experiences, and spectral efficiency.

A Gaze-based Real-time and Low Complexity No-reference Video Quality Assessment Technique for Video Gaming

Multimedia Tools and Applications, Aug 4, 2023

Scalable Video Streaming Adaptive to Time-Varying IEEE 802.11 MAC Parameters

IEICE Transactions on Communications, Oct 1, 2008

ABSTRACT This letter proposes a QoS control method for video streaming service over wireless netw... more ABSTRACT This letter proposes a QoS control method for video streaming service over wireless networks. Based on statistical analysis, the time-varying MAC parameters highly related to channel condition are selected to predict available bitrate. Adaptive bitrate control of scalably-encoded video guarantees continuity in streaming service even if the channel condition changes abruptly.

Mobile Information Systems, 2015

This paper proposes a method for channel allocation based on video content requirements and the q... more This paper proposes a method for channel allocation based on video content requirements and the quality of the available channels in cognitive radio networks (CRNs). Our objective is to save network bandwidth and achieve high-quality video delivery. In this method, the content is divided into clusters based on scene complexity and PSNR. To allocate channel to the clusters over multichannel CRNs, we first need to identify the licensee's activity and then maximize the opportunistic usage accordingly. Therefore, we classify short and long time transmission opportunities based on the licensee's activities using a Bayesian nonparametric inference model. Furthermore, to prevent transmission interruption, we consider the underlay mode for transmission of the clusters with a lower bitrate. Next, we map the available spectrum opportunities to the content clusters according to both the quality of the channels and the requirements of the clusters. Then, a distortion optimization model is constructed according to the network transmission mechanism. Finally, to maximize the average quality of the delivered video, an optimization problem is defined to determine the best bitrate for each cluster by maximizing the sum of the logarithms of the frame rates. Our extensive simulation results prove the superior performance of the proposed method in terms of spectrum efficiency and the quality of delivered video.

Journal of Web Engineering, Jan 17, 2022

Media technology has been developed to give users a sense of immersion. Recent media using 3D spa... more Media technology has been developed to give users a sense of immersion. Recent media using 3D spatial data, such as augmented reality and virtual reality, has attracted attention. A point cloud is a data format that consists of a number of points, and thus can express 3D media using coordinates and color information for each point. Since a point cloud has a larger capacity than 2D images, a technology to compress the point cloud is required, i.e., standardized in the international standard organization MPEG as a video-based point cloud compression (V-PCC). V-PCC decomposes 3D point cloud data into 2D patches along orthogonal directions, and those patches are placed into a 2D image sequence, and then compressed using existing 2D video codecs. However, data loss may occur while converting a 3D point cloud into a 2D image sequence and encoding this sequence using a legacy video codec. This data loss can cause deterioration in the quality of a reconstructed point cloud.

Fuzzy Logic-Based Throughput Enhancement for Cognitive Radio Networks

대한전자공학회 학술대회, Nov 1, 2013

ABSTRACT Fuzzy logic has a great potential to improve the throughput of the brain empowered cogni... more ABSTRACT Fuzzy logic has a great potential to improve the throughput of the brain empowered cognitive radio network (CRNs). Cognitive radio-enabled users are called secondary users (SUs) while the license users are called the primary users (PUs). SUs exploit the white spaces opportunistically available in license channels. SU have to immediately vacate the license channel and switch to some other available channel as PU arrival is detected or interference with PU goes beyond a predefined limit. Performance of SU severely degrades if successive channel switching happens; furthermore taking the channel witching decisions based on crisp logic is not suitable approach in brain empowered CRNs where sensing information is not only imprecise and inaccurate but also involve a major factor of uncertainty. In this paper, we deal channel selection and switching jointly and propose a fuzzy logic-based channel selection and switching decision system for enhancing the throughput of the CRNs. Our system reduces the SU channel switching rate as well as channel selection is more adaptable for CRNs.

A Task Offloading and Reallocation Scheme for Passenger Assistance Using Fog Computing

IEEE Transactions on Network and Service Management, Sep 1, 2022

360 VR 비디오 스트리밍 서비스의 QoS 제어를 위한 MANE Cloud 시스템의 설계 및 구현

한국통신학회, Sep 1, 2020

Effective Streaming technology of a layered encoding Video Application supporting QoS mechanism in the Internet

Energy Efficient Proactive Routing Scheme for Enabling Reliable Communication in Underwater Internet of Things

IEEE Transactions on Network Science and Engineering, 2021

The Underwater Internet of Things (UIoT) is a network of smart interconnected devices operating u... more The Underwater Internet of Things (UIoT) is a network of smart interconnected devices operating under various aqueous environments. In UIoT, due to aqueous feature of signal absorption, data signals are transmitted at low frequency. Similarly, significant interference and collisions degrade transmission quality, resulting in a low Packet Delivery Ratio (PDR) and a long End-to-End (E2E) delay. Moreover, a significant amount of energy is being wasted due to the void hole problem, which arises when the source node does not identify an instant forwarder node. Thus, a reliable communication with enhanced network lifetime is highly desired in UIoT. Therefore, this work proposes a proactive energy Efficient Layer-by-Layer Watchman-based Collision Free Routing (ELW-CFR) scheme to address the above mentioned issues. The proposed scheme provides the low E2E delay and high PDR while avoiding the void hole problem. Extensive simulations have been performed to show the performance superiority of the proposed scheme against the state-of-the-art schemes.

The stringent requirements of wireless multimediatransmission lead to very high radio spectrum so... more The stringent requirements of wireless multimediatransmission lead to very high radio spectrum solicitation. Although the radio spectrum is considered as a scarce resource, theissue with spectrum availability is not scarcity, but the inefficientutilization. Unique characteristics of cognitive radio (CR) suchas flexibility, adaptability, and interoperability, particularly havecontributed to it being the optimum technological candidate toalleviate the issue of spectrum scarcity for multimedia communications. However, multimedia communications over CRnetworks (MCRNs) as a bandwidth-hungry, delay-sensitive, andloss-tolerant service, exposes several severe challenges speciallyto guarantee quality of service (QoS) and quality of experience(QoE). As a result, to date, different schemes based on source andchannel coding, multicast, and distributed streaming, have beenexamined to improve the QoS/QoE in MCRNs. In this paper,we survey QoS/QoE provisioning schemes in MCRNs. We firstdiscuss the ...

IEEE Transactions on Vehicular Technology, 2018

Accommodating the fast-growing multimedia traffic demands at low cost is critical to ensure the f... more Accommodating the fast-growing multimedia traffic demands at low cost is critical to ensure the future competitiveness of cellular networks. Cognitive Radio (CR) emerges as a key technology to enhance radio spectrum utilization and provides an effective solution to meet critical spectrum demands for future mobile multimedia traffics. In this paper, we investigate reliable downlink video transmission in underlay cellular cognitive radio networks by means of cooperative diversity. We use RaptorQ code as the Application Layer Forward Error Correction (AL-FEC) scheme to combat packet loss arising from primary user interference and other channel conditions such as channel fading. For implementing cooperative diversity, we select the best relay based on the ability of successful decoding using RaptorQ and the value of signal-to-interference-plus-noise ratio (SINR) at the destination node. Moreover, for efficient primary user channel utilization, the selected relay performs merging of the encoding coefficients before forwarding to the destination. We evaluate the performance of the proposed framework under various time sharing scenarios between the direct and best indirect transmission links in terms of decoding overhead, probability of decoding failure, and peak signal-to-noise ratio (PSNR) of the received videos. Numerical results show that the proposed scheme outperforms the baseline transmission scheme, and conventional relaying schemes using Amplify-and-Forward (AaF) and Decodeand-Forward (DaF) transmission techniques.

IEICE Transactions on Information and Systems, 2010

This letter proposes a method to retrieve the original image X out of multiple sets of SI (Side I... more This letter proposes a method to retrieve the original image X out of multiple sets of SI (Side Information) in distributed video coding (DVC). Using Turbo decoding methods, the most reliable segments from the decoded Y i 's were selected for the composition of Y ∞ , whose conditional entropy H(X|Y ∞ ) became much lower than any individual conditional entropy H(X|Y i ). This proposal has improved the peak signal-tonoise ratio (PSNR) by 1.1 to 1.8 dB, compared to the conventional single SI-based approach.

Journal of Broadcast Engineering, 2008

This paper defines QoE (Quality of Experience) for multi-view video streaming service over WiBro ... more This paper defines QoE (Quality of Experience) for multi-view video streaming service over WiBro and proposes the CLO (Cross-Layer Optimization) algorithm can maximize this. Proposal CLO algorithm contains from physical layer to video layer. Under the time-varying wireless channel condition, the CLO technique takes view-wise and the temporal priority of the multi-view video into consideration in order to decide the transmission of frames and its FEC level. At the handover situation, it is shown through computer simulation that the optimal quality of the multi-view video can be achieved using the minimum amount of resources if the proposed CLO technique is applied.

As the necessity of haptic technology in the metaverse area has been increasing, a number of glov... more As the necessity of haptic technology in the metaverse area has been increasing, a number of glove-shaped haptic devices have been developed and commercialized. However, current commercialized devices are highly expensive for not only developing countries but also for average individuals. Therefore, this paper sets out to present an affordable and practically usable haptic glove. The three main elements contested in this paper are Leap Motion Controller (LMC), which is used to improve and stabilize the recognition of hand tracking in Unity. Elasticity, which pertains using string-based haptic feedback wherein our Haptic Glove generates an elastic effect of a virtual object. Lastly, an EMG sensor: By connecting the EMG sensor and the Haptic Glove, this paper proposes the possibility of expanding the use of the Haptic Gloves for fine motor development and rehabilitation.

Efficient Computation Offloading in Mobile Cloud Computing for Video Streaming Over 5G

Computers, materials & continua, 2019

Performance of scalable video coding with respect to differentiated service requirements

Proceedings of SPIE, Aug 18, 2005

ABSTRACT Multimedia service can be categorized as conversational, streaming, and download service... more ABSTRACT Multimedia service can be categorized as conversational, streaming, and download services, which differ in temporal and semantic quality requirements. Performance of SVC (Scalable video coding) is analyzed in the three dimensional (spatio-temporal) frequency domain. Based on the analysis, SVC scheme can be modified to satisfy various requirements as being compliant to the international standards. Decoding without enhancement layer data results in drift phenomenon. Several drift-free techniques are analyzed.

Directional Filtering for Upsampling According to Direction Information of the Base Layer in the JVT/SVC Codec

Springer eBooks, 2006

ABSTRACT When the reconstructed image of the base layer is up-sampled for decoding the enhancemen... more ABSTRACT When the reconstructed image of the base layer is up-sampled for decoding the enhancement layer of spatial scalability, direction information derived during decoding the spatially lower layer is used. That is direction information used for Intra prediction which is used for up-sampling again. In most cases, it shows 0.1-0.5dB quality improvement in images up-sampled by using directional filtering compared to those up-sampled conventionally. The same interpolation algorithm should be used in both the encoder and decoder.

Efficient stereoscopic contents file format on the basis of ISO base media file format

Proceedings of SPIE, Feb 5, 2009

A lot of 3D contents haven been widely used for multimedia services, however, real 3D video conte... more A lot of 3D contents haven been widely used for multimedia services, however, real 3D video contents have been adopted for a limited applications such as a specially designed 3D cinema. This is because of the difficulty of capturing real 3D video contents and the limitation of display devices available in a market. However, diverse types of display devices for

IEEE Access, 2018

Recently, device-to-device (D2D)-underlaid fifth-generation (5G) cellular networks have received ... more Recently, device-to-device (D2D)-underlaid fifth-generation (5G) cellular networks have received plenty of attention because of their ability to save network resources and to reduce energy consumption. Most existing algorithms for multimedia services over D2D networks consider only the signalto-noise ratio (SNR) and ignore temporal requirements, which do not provide optimum performances. To overcome this issue, we propose a framework for a cross-layer D2D link control system, which guarantees the quality of service and improves the quality of experience (QoE) for live video streaming with different priorities and delay constraints. In this framework, we considered three techniques, including priority-based video transmission, flexible communication mode switching of user equipment, and subset-based relay assignment. According to the live video generation period, our system dynamically adjusts the ratio between cellular and D2D mode durations in each unit of the communication period for each user individually. Our proposal also considerably reduces the duration and frequency of video playback freezing by delivering at least the minimum service quality of the delivered video to the sink users even in the shadow area and therefore improves the QoE for all users while minimizing energy consumption. System-level simulation shows that the proposed algorithm outperforms other methods in terms of the average mean time to failure, average peak SNR, and average energy consumption.

IEEE Access, 2018

Heterogeneity is one of the key features that characterizes the future generation of cellular net... more Heterogeneity is one of the key features that characterizes the future generation of cellular networks, 5G and beyond. However, streaming high-quality bandwidth-hungry multimedia contents over bandwidth-constrained 5G heterogeneous networks (5G HetNets) involves various significant challenges, including long video start time, video start failures, frequent buffering and stalling, and low quality of experience (QoE). Traditional multimedia streaming technologies, however, do not pay attention to either the available network bandwidth or the interaction between content characteristics and resources. To reduce network strain and improve QoE, we propose ''Context-Aware Streaming over 5G HetNets (CASH)'' that allows us to achieve a tradeoff between content-context and network-context. The proposed CASH fundamentally works in a multi-step process. First, the CASH comes with an integrated architecture that includes a media server, a flow scheduler, and a single radio controller (SRC). The SRC and the user equipment (UE) of interest cooperatively prepare a metadata file that contains the network-context. Second, based on the metadata file, which can be accessed from the SRC in the media preparation server, we analyze and cluster the contents based on the content-context, e.g., the actual bitrate of each scene. The metadata file is then updated by adding the content-context information. Third, the flow scheduler basically controls the flow of the clusters of the contents in the server-push mode and conveys that to the appropriate radio access technology (RAT) conforming to the bitrate of the clusters and bandwidth delivered by RATs. Finally, the UE will aggregate the received packets and will play-back the content. We analytically show the validity of CASH. Also, extensive simulations are performed to demonstrate that CASH offers substantial performance improvements compared with exiting works in terms of peak data rate, latency, users' experiences, and spectral efficiency.

A Gaze-based Real-time and Low Complexity No-reference Video Quality Assessment Technique for Video Gaming

Multimedia Tools and Applications, Aug 4, 2023

Scalable Video Streaming Adaptive to Time-Varying IEEE 802.11 MAC Parameters

IEICE Transactions on Communications, Oct 1, 2008

ABSTRACT This letter proposes a QoS control method for video streaming service over wireless netw... more ABSTRACT This letter proposes a QoS control method for video streaming service over wireless networks. Based on statistical analysis, the time-varying MAC parameters highly related to channel condition are selected to predict available bitrate. Adaptive bitrate control of scalably-encoded video guarantees continuity in streaming service even if the channel condition changes abruptly.

Mobile Information Systems, 2015

This paper proposes a method for channel allocation based on video content requirements and the q... more This paper proposes a method for channel allocation based on video content requirements and the quality of the available channels in cognitive radio networks (CRNs). Our objective is to save network bandwidth and achieve high-quality video delivery. In this method, the content is divided into clusters based on scene complexity and PSNR. To allocate channel to the clusters over multichannel CRNs, we first need to identify the licensee's activity and then maximize the opportunistic usage accordingly. Therefore, we classify short and long time transmission opportunities based on the licensee's activities using a Bayesian nonparametric inference model. Furthermore, to prevent transmission interruption, we consider the underlay mode for transmission of the clusters with a lower bitrate. Next, we map the available spectrum opportunities to the content clusters according to both the quality of the channels and the requirements of the clusters. Then, a distortion optimization model is constructed according to the network transmission mechanism. Finally, to maximize the average quality of the delivered video, an optimization problem is defined to determine the best bitrate for each cluster by maximizing the sum of the logarithms of the frame rates. Our extensive simulation results prove the superior performance of the proposed method in terms of spectrum efficiency and the quality of delivered video.

Journal of Web Engineering, Jan 17, 2022

Media technology has been developed to give users a sense of immersion. Recent media using 3D spa... more Media technology has been developed to give users a sense of immersion. Recent media using 3D spatial data, such as augmented reality and virtual reality, has attracted attention. A point cloud is a data format that consists of a number of points, and thus can express 3D media using coordinates and color information for each point. Since a point cloud has a larger capacity than 2D images, a technology to compress the point cloud is required, i.e., standardized in the international standard organization MPEG as a video-based point cloud compression (V-PCC). V-PCC decomposes 3D point cloud data into 2D patches along orthogonal directions, and those patches are placed into a 2D image sequence, and then compressed using existing 2D video codecs. However, data loss may occur while converting a 3D point cloud into a 2D image sequence and encoding this sequence using a legacy video codec. This data loss can cause deterioration in the quality of a reconstructed point cloud.

Fuzzy Logic-Based Throughput Enhancement for Cognitive Radio Networks

대한전자공학회 학술대회, Nov 1, 2013

ABSTRACT Fuzzy logic has a great potential to improve the throughput of the brain empowered cogni... more ABSTRACT Fuzzy logic has a great potential to improve the throughput of the brain empowered cognitive radio network (CRNs). Cognitive radio-enabled users are called secondary users (SUs) while the license users are called the primary users (PUs). SUs exploit the white spaces opportunistically available in license channels. SU have to immediately vacate the license channel and switch to some other available channel as PU arrival is detected or interference with PU goes beyond a predefined limit. Performance of SU severely degrades if successive channel switching happens; furthermore taking the channel witching decisions based on crisp logic is not suitable approach in brain empowered CRNs where sensing information is not only imprecise and inaccurate but also involve a major factor of uncertainty. In this paper, we deal channel selection and switching jointly and propose a fuzzy logic-based channel selection and switching decision system for enhancing the throughput of the CRNs. Our system reduces the SU channel switching rate as well as channel selection is more adaptable for CRNs.

A Task Offloading and Reallocation Scheme for Passenger Assistance Using Fog Computing

IEEE Transactions on Network and Service Management, Sep 1, 2022

360 VR 비디오 스트리밍 서비스의 QoS 제어를 위한 MANE Cloud 시스템의 설계 및 구현

한국통신학회, Sep 1, 2020

Effective Streaming technology of a layered encoding Video Application supporting QoS mechanism in the Internet

Energy Efficient Proactive Routing Scheme for Enabling Reliable Communication in Underwater Internet of Things

IEEE Transactions on Network Science and Engineering, 2021

The Underwater Internet of Things (UIoT) is a network of smart interconnected devices operating u... more The Underwater Internet of Things (UIoT) is a network of smart interconnected devices operating under various aqueous environments. In UIoT, due to aqueous feature of signal absorption, data signals are transmitted at low frequency. Similarly, significant interference and collisions degrade transmission quality, resulting in a low Packet Delivery Ratio (PDR) and a long End-to-End (E2E) delay. Moreover, a significant amount of energy is being wasted due to the void hole problem, which arises when the source node does not identify an instant forwarder node. Thus, a reliable communication with enhanced network lifetime is highly desired in UIoT. Therefore, this work proposes a proactive energy Efficient Layer-by-Layer Watchman-based Collision Free Routing (ELW-CFR) scheme to address the above mentioned issues. The proposed scheme provides the low E2E delay and high PDR while avoiding the void hole problem. Extensive simulations have been performed to show the performance superiority of the proposed scheme against the state-of-the-art schemes.

The stringent requirements of wireless multimediatransmission lead to very high radio spectrum so... more The stringent requirements of wireless multimediatransmission lead to very high radio spectrum solicitation. Although the radio spectrum is considered as a scarce resource, theissue with spectrum availability is not scarcity, but the inefficientutilization. Unique characteristics of cognitive radio (CR) suchas flexibility, adaptability, and interoperability, particularly havecontributed to it being the optimum technological candidate toalleviate the issue of spectrum scarcity for multimedia communications. However, multimedia communications over CRnetworks (MCRNs) as a bandwidth-hungry, delay-sensitive, andloss-tolerant service, exposes several severe challenges speciallyto guarantee quality of service (QoS) and quality of experience(QoE). As a result, to date, different schemes based on source andchannel coding, multicast, and distributed streaming, have beenexamined to improve the QoS/QoE in MCRNs. In this paper,we survey QoS/QoE provisioning schemes in MCRNs. We firstdiscuss the ...

IEEE Transactions on Vehicular Technology, 2018

Accommodating the fast-growing multimedia traffic demands at low cost is critical to ensure the f... more Accommodating the fast-growing multimedia traffic demands at low cost is critical to ensure the future competitiveness of cellular networks. Cognitive Radio (CR) emerges as a key technology to enhance radio spectrum utilization and provides an effective solution to meet critical spectrum demands for future mobile multimedia traffics. In this paper, we investigate reliable downlink video transmission in underlay cellular cognitive radio networks by means of cooperative diversity. We use RaptorQ code as the Application Layer Forward Error Correction (AL-FEC) scheme to combat packet loss arising from primary user interference and other channel conditions such as channel fading. For implementing cooperative diversity, we select the best relay based on the ability of successful decoding using RaptorQ and the value of signal-to-interference-plus-noise ratio (SINR) at the destination node. Moreover, for efficient primary user channel utilization, the selected relay performs merging of the encoding coefficients before forwarding to the destination. We evaluate the performance of the proposed framework under various time sharing scenarios between the direct and best indirect transmission links in terms of decoding overhead, probability of decoding failure, and peak signal-to-noise ratio (PSNR) of the received videos. Numerical results show that the proposed scheme outperforms the baseline transmission scheme, and conventional relaying schemes using Amplify-and-Forward (AaF) and Decodeand-Forward (DaF) transmission techniques.

IEICE Transactions on Information and Systems, 2010

This letter proposes a method to retrieve the original image X out of multiple sets of SI (Side I... more This letter proposes a method to retrieve the original image X out of multiple sets of SI (Side Information) in distributed video coding (DVC). Using Turbo decoding methods, the most reliable segments from the decoded Y i 's were selected for the composition of Y ∞ , whose conditional entropy H(X|Y ∞ ) became much lower than any individual conditional entropy H(X|Y i ). This proposal has improved the peak signal-tonoise ratio (PSNR) by 1.1 to 1.8 dB, compared to the conventional single SI-based approach.

Journal of Broadcast Engineering, 2008

This paper defines QoE (Quality of Experience) for multi-view video streaming service over WiBro ... more This paper defines QoE (Quality of Experience) for multi-view video streaming service over WiBro and proposes the CLO (Cross-Layer Optimization) algorithm can maximize this. Proposal CLO algorithm contains from physical layer to video layer. Under the time-varying wireless channel condition, the CLO technique takes view-wise and the temporal priority of the multi-view video into consideration in order to decide the transmission of frames and its FEC level. At the handover situation, it is shown through computer simulation that the optimal quality of the multi-view video can be achieved using the minimum amount of resources if the proposed CLO technique is applied.