Pub Date : 2008-11-05DOI: 10.1109/MMSP.2008.4665090
Kenneth Vermeirsch, J. D. Cock, S. Notebaert, P. Lambert, R. Walle
To attain efficient coding of sequences with complex motion activity, modern video coding standards allow variable block sizes to be employed in temporal prediction. A block with complex motion can be partitioned into two equal-sized halves or into four quadrants. In this paper we study the impact of allowing blocks to be partitioned in two unequal subpartitions. Additionally, we allow block partitioning along diagonal edges. These provisions allows encoders to better adapt to the local characteristics of the motion activity in a video sequence. We verified experimentally that the presence of partitioning edges that do not coincide with transform boundaries does not negatively impact the decorrelating strength of the residual transform, so the proposed extended partitioning strategies can be applied regardless of the details of the residual coder. Implementing the proposed extended partitioning modes in an H.264/AVC coder at the macroblock and submacroblock level, we observe that coding efficiency gains are greatest in low-resolution sequences, where moving features in the video sequence tend to be more spatially localized. For CIF and QCIF sequences we achieve a bit rate reduction of about 3-6% over a wide fidelity range.
{"title":"Increased flexibility in inter picture partitioning","authors":"Kenneth Vermeirsch, J. D. Cock, S. Notebaert, P. Lambert, R. Walle","doi":"10.1109/MMSP.2008.4665090","DOIUrl":"https://doi.org/10.1109/MMSP.2008.4665090","url":null,"abstract":"To attain efficient coding of sequences with complex motion activity, modern video coding standards allow variable block sizes to be employed in temporal prediction. A block with complex motion can be partitioned into two equal-sized halves or into four quadrants. In this paper we study the impact of allowing blocks to be partitioned in two unequal subpartitions. Additionally, we allow block partitioning along diagonal edges. These provisions allows encoders to better adapt to the local characteristics of the motion activity in a video sequence. We verified experimentally that the presence of partitioning edges that do not coincide with transform boundaries does not negatively impact the decorrelating strength of the residual transform, so the proposed extended partitioning strategies can be applied regardless of the details of the residual coder. Implementing the proposed extended partitioning modes in an H.264/AVC coder at the macroblock and submacroblock level, we observe that coding efficiency gains are greatest in low-resolution sequences, where moving features in the video sequence tend to be more spatially localized. For CIF and QCIF sequences we achieve a bit rate reduction of about 3-6% over a wide fidelity range.","PeriodicalId":402287,"journal":{"name":"2008 IEEE 10th Workshop on Multimedia Signal Processing","volume":"28 7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122707554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-11-05DOI: 10.1109/MMSP.2008.4665124
Aditya Mavlankar, Jeonghun Noh, Pierpaolo Baccichet, B. Girod
We consider the general scenario where content hosted by the server comprises streams and each peer can subscribe one or more streams. Multiple multicast trees are built to deliver the streams to respective peers while exploiting the overlap of their interests for efficient and scalable delivery. We propose an optimization framework for allocating server bandwidth to minimize distortion across the peer population. We apply the framework to a novel application, peer-to-peer (P2P) multicast live video streaming with virtual pan/tilt/zoom functionality. In this application, each user can watch arbitrary regions of a high-spatial-resolution scene yet the system exploits overlapping interests by building multicast trees. Experimental results indicate that optimal server bandwidth allocation enhances the delivered quality across the peer population.
{"title":"Optimal server bandwidth allocation for streaming multiple streams via P2P multicast","authors":"Aditya Mavlankar, Jeonghun Noh, Pierpaolo Baccichet, B. Girod","doi":"10.1109/MMSP.2008.4665124","DOIUrl":"https://doi.org/10.1109/MMSP.2008.4665124","url":null,"abstract":"We consider the general scenario where content hosted by the server comprises streams and each peer can subscribe one or more streams. Multiple multicast trees are built to deliver the streams to respective peers while exploiting the overlap of their interests for efficient and scalable delivery. We propose an optimization framework for allocating server bandwidth to minimize distortion across the peer population. We apply the framework to a novel application, peer-to-peer (P2P) multicast live video streaming with virtual pan/tilt/zoom functionality. In this application, each user can watch arbitrary regions of a high-spatial-resolution scene yet the system exploits overlapping interests by building multicast trees. Experimental results indicate that optimal server bandwidth allocation enhances the delivered quality across the peer population.","PeriodicalId":402287,"journal":{"name":"2008 IEEE 10th Workshop on Multimedia Signal Processing","volume":"25 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122463643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-11-05DOI: 10.1109/MMSP.2008.4665217
Samuel Kim, Shrikanth S. Narayanan
A new chroma-based dynamic feature vector is proposed inspired by psychophysical observations that the human auditory system detects reltative pitch changes rather than absolute pitch values. The proposed chroma-based dynamic feature vector describes the relative pitch change intervals. The utility of the proposed feature vector incorporated with a music fingerprint extraction algorithm is experimentally explored within a music cover song identification framework. The results with a classical music database suggest that the proposed biologically plausible dynamic chroma feature vector can be successfully added to the conventional chroma feature vector as a complementary feature; it provides a 5.8% relative performance improvement.
{"title":"Dynamic chroma feature vectors with applications to cover song identification","authors":"Samuel Kim, Shrikanth S. Narayanan","doi":"10.1109/MMSP.2008.4665217","DOIUrl":"https://doi.org/10.1109/MMSP.2008.4665217","url":null,"abstract":"A new chroma-based dynamic feature vector is proposed inspired by psychophysical observations that the human auditory system detects reltative pitch changes rather than absolute pitch values. The proposed chroma-based dynamic feature vector describes the relative pitch change intervals. The utility of the proposed feature vector incorporated with a music fingerprint extraction algorithm is experimentally explored within a music cover song identification framework. The results with a classical music database suggest that the proposed biologically plausible dynamic chroma feature vector can be successfully added to the conventional chroma feature vector as a complementary feature; it provides a 5.8% relative performance improvement.","PeriodicalId":402287,"journal":{"name":"2008 IEEE 10th Workshop on Multimedia Signal Processing","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122532191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-11-05DOI: 10.1109/MMSP.2008.4665114
Ismaël Daribo, C. Tillier, B. Pesquet-Popescu
Multi-view video and 3D television are emerging applications raising the problem of efficient encoding of a depth map, in addition to classical texture images. This paper investigates depth image coding via an adaptive wavelet lifting scheme. Switching between long filters in homogeneous areas and short filters over the edges of the depth map is decided based on the contours detected in the texture image. The method takes thus into consideration the correlation existing between the edges in the texture and in the depth image, leading to an improved encoding of the latter one.
{"title":"Adaptive wavelet coding of the depth map for stereoscopic view synthesis","authors":"Ismaël Daribo, C. Tillier, B. Pesquet-Popescu","doi":"10.1109/MMSP.2008.4665114","DOIUrl":"https://doi.org/10.1109/MMSP.2008.4665114","url":null,"abstract":"Multi-view video and 3D television are emerging applications raising the problem of efficient encoding of a depth map, in addition to classical texture images. This paper investigates depth image coding via an adaptive wavelet lifting scheme. Switching between long filters in homogeneous areas and short filters over the edges of the depth map is decided based on the contours detected in the texture image. The method takes thus into consideration the correlation existing between the edges in the texture and in the depth image, leading to an improved encoding of the latter one.","PeriodicalId":402287,"journal":{"name":"2008 IEEE 10th Workshop on Multimedia Signal Processing","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114362243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-11-05DOI: 10.1109/MMSP.2008.4665215
M. Triki, D. Slock, A. Triki
A key building block in music transcription and indexing operations is the decomposition of music signals into notes. We model a note signal as a periodic signal with (slow) frequency-selective amplitude modulation and global time warping. Time-varying frequency-selective amplitude modulation allows the various harmonics of the periodic signal to decay at different speeds. Time-warping allows for some limited global frequency modulation. The bandlimited variation of the frequency-selective amplitude modulation and of the global time warping gets expressed through a subsampled representation and parametrization of the corresponding signals. Assuming additive white Gaussian noise, a maximum likelihood approach is proposed for the estimation of the model parameters and the optimization is performed in an iterative (cyclic) fashion that leads to a sequence of simple least-squares problems.
{"title":"Periodic signal extraction with frequency-selective amplitude modulation and global time-warping for music signal decomposition","authors":"M. Triki, D. Slock, A. Triki","doi":"10.1109/MMSP.2008.4665215","DOIUrl":"https://doi.org/10.1109/MMSP.2008.4665215","url":null,"abstract":"A key building block in music transcription and indexing operations is the decomposition of music signals into notes. We model a note signal as a periodic signal with (slow) frequency-selective amplitude modulation and global time warping. Time-varying frequency-selective amplitude modulation allows the various harmonics of the periodic signal to decay at different speeds. Time-warping allows for some limited global frequency modulation. The bandlimited variation of the frequency-selective amplitude modulation and of the global time warping gets expressed through a subsampled representation and parametrization of the corresponding signals. Assuming additive white Gaussian noise, a maximum likelihood approach is proposed for the estimation of the model parameters and the optimization is performed in an iterative (cyclic) fashion that leads to a sequence of simple least-squares problems.","PeriodicalId":402287,"journal":{"name":"2008 IEEE 10th Workshop on Multimedia Signal Processing","volume":"170 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117277558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-11-05DOI: 10.1109/MMSP.2008.4665147
S. Velusamy, S. Bhatnagar, S. Basavaraja, V. Sridhar
With the availability of a huge amount of video data on various sources, efficient video retrieval tools are increasingly in demand. Video being a multi-modal data, the perceptions of ldquorelevancerdquo between the user provided query video (in case of Query-By-Example type of video search) and retrieved video clips are subjective in nature. We present an efficient video retrieval method that takes userpsilas feedback on the relevance of retrieved videos and iteratively reformulates the input query feature vectors (QFV) for improved video retrieval. The QFV reformulation is done by a simple, but powerful feature weight optimization method based on Simultaneous Perturbation Stochastic Approximation (SPSA) technique. A video retrieval system with video indexing, searching and relevance feedback (RF) phases is built for demonstrating the performance of the proposed method. The query and database videos are indexed using the conventional video features like color, texture, etc. However, we use the comprehensive and novel methods of feature representations, and a spatio-temporal distance measure to retrieve the top M videos that are similar to the query. In feedback phase, the user activated iterative on the previously retrieved videos is used to reformulate the QFV weights (measure of importance) that reflect the userpsilas preference, automatically. It is our observation that a few iterations of such feedback are generally sufficient for retrieving the desired video clips. The novel application of SPSA based RF for user-oriented feature weights optimization makes the proposed method to be distinct from the existing ones. The experimental results show that the proposed RF based video retrieval exhibit good performance.
{"title":"SPSA based feature relevance estimation for video retrieval","authors":"S. Velusamy, S. Bhatnagar, S. Basavaraja, V. Sridhar","doi":"10.1109/MMSP.2008.4665147","DOIUrl":"https://doi.org/10.1109/MMSP.2008.4665147","url":null,"abstract":"With the availability of a huge amount of video data on various sources, efficient video retrieval tools are increasingly in demand. Video being a multi-modal data, the perceptions of ldquorelevancerdquo between the user provided query video (in case of Query-By-Example type of video search) and retrieved video clips are subjective in nature. We present an efficient video retrieval method that takes userpsilas feedback on the relevance of retrieved videos and iteratively reformulates the input query feature vectors (QFV) for improved video retrieval. The QFV reformulation is done by a simple, but powerful feature weight optimization method based on Simultaneous Perturbation Stochastic Approximation (SPSA) technique. A video retrieval system with video indexing, searching and relevance feedback (RF) phases is built for demonstrating the performance of the proposed method. The query and database videos are indexed using the conventional video features like color, texture, etc. However, we use the comprehensive and novel methods of feature representations, and a spatio-temporal distance measure to retrieve the top M videos that are similar to the query. In feedback phase, the user activated iterative on the previously retrieved videos is used to reformulate the QFV weights (measure of importance) that reflect the userpsilas preference, automatically. It is our observation that a few iterations of such feedback are generally sufficient for retrieving the desired video clips. The novel application of SPSA based RF for user-oriented feature weights optimization makes the proposed method to be distinct from the existing ones. The experimental results show that the proposed RF based video retrieval exhibit good performance.","PeriodicalId":402287,"journal":{"name":"2008 IEEE 10th Workshop on Multimedia Signal Processing","volume":"03 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129851200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-11-05DOI: 10.1109/MMSP.2008.4665078
Hsuan-Ying Chen, Jin-Jang Leou
In this study, a new edge-directed image interpolation approach using visual attention model and particle swarm optimization (PSO) is proposed. First, a high-quality saliency map of an image to be interpolated is generated by the proposed visual attention model in an effective manner. Then, based on the saliency map, bilinear interpolation and the proposed PSO interpolation are employed for non-saliency blocks (non-ROIs) and saliency blocks (ROIs), respectively, to obtain the final interpolation results. The proposed approach is applicable for image interpolation with arbitrary magnification factors (MFs). Based on the experimental results obtained in this study, the interpolation results of the proposed approach are better than those of three comparison methods.
{"title":"Image interpolation using visual attention model and particle swarm optimization","authors":"Hsuan-Ying Chen, Jin-Jang Leou","doi":"10.1109/MMSP.2008.4665078","DOIUrl":"https://doi.org/10.1109/MMSP.2008.4665078","url":null,"abstract":"In this study, a new edge-directed image interpolation approach using visual attention model and particle swarm optimization (PSO) is proposed. First, a high-quality saliency map of an image to be interpolated is generated by the proposed visual attention model in an effective manner. Then, based on the saliency map, bilinear interpolation and the proposed PSO interpolation are employed for non-saliency blocks (non-ROIs) and saliency blocks (ROIs), respectively, to obtain the final interpolation results. The proposed approach is applicable for image interpolation with arbitrary magnification factors (MFs). Based on the experimental results obtained in this study, the interpolation results of the proposed approach are better than those of three comparison methods.","PeriodicalId":402287,"journal":{"name":"2008 IEEE 10th Workshop on Multimedia Signal Processing","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124760795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-11-05DOI: 10.1109/MMSP.2008.4665116
Zhi Li, Y. Lin, D. Varodayan, Pierpaolo Baccichet, B. Girod
We investigate retransmission-based robust video streaming over lossy packet networks in this paper. We propose to send a thumbnail video along with the video packets. The thumbnail video is Wyner-Ziv-coded to exploit its correlation with the primary video. The receiver decodes the primary video with the help of error concealment to mitigate packet losses. Upon receiving and successfully decoding the thumbnail, the receiver can estimate the local distortion due to packet losses and make intelligent decisions on which packets are needed for retransmission. Additional gain in video quality can be achieved by using the thumbnail to aid error concealment. Our experimental results demonstrate gains over previously proposed distortion-unaware heuristic methods.
{"title":"Distortion-aware retransmission and concealment of video packets using a Wyner-Ziv-coded thumbnail","authors":"Zhi Li, Y. Lin, D. Varodayan, Pierpaolo Baccichet, B. Girod","doi":"10.1109/MMSP.2008.4665116","DOIUrl":"https://doi.org/10.1109/MMSP.2008.4665116","url":null,"abstract":"We investigate retransmission-based robust video streaming over lossy packet networks in this paper. We propose to send a thumbnail video along with the video packets. The thumbnail video is Wyner-Ziv-coded to exploit its correlation with the primary video. The receiver decodes the primary video with the help of error concealment to mitigate packet losses. Upon receiving and successfully decoding the thumbnail, the receiver can estimate the local distortion due to packet losses and make intelligent decisions on which packets are needed for retransmission. Additional gain in video quality can be achieved by using the thumbnail to aid error concealment. Our experimental results demonstrate gains over previously proposed distortion-unaware heuristic methods.","PeriodicalId":402287,"journal":{"name":"2008 IEEE 10th Workshop on Multimedia Signal Processing","volume":"48 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129447734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-11-05DOI: 10.1109/MMSP.2008.4665037
HongJiang Zhang
Summary form only given. After 15 years of extensive research efforts, multimedia retrieval has final come to its prime time when everything becomes accessible on the Web. However, Web search both provides a new paradigm and poses challenge to multimedia retrieval research. It calls for a rethinking of the traditional content-based approaches, especially in how to make use the massive but noisy meta-data associated with Web pages and links. In this talk, we will first review some familiar approaches in content-based multimedia retrieval and examine their limits. We will then present a few new efforts in web multimedia search to illustrate some new thoughts in this space.
{"title":"Multimedia search: Past and current approaches","authors":"HongJiang Zhang","doi":"10.1109/MMSP.2008.4665037","DOIUrl":"https://doi.org/10.1109/MMSP.2008.4665037","url":null,"abstract":"Summary form only given. After 15 years of extensive research efforts, multimedia retrieval has final come to its prime time when everything becomes accessible on the Web. However, Web search both provides a new paradigm and poses challenge to multimedia retrieval research. It calls for a rethinking of the traditional content-based approaches, especially in how to make use the massive but noisy meta-data associated with Web pages and links. In this talk, we will first review some familiar approaches in content-based multimedia retrieval and examine their limits. We will then present a few new efforts in web multimedia search to illustrate some new thoughts in this space.","PeriodicalId":402287,"journal":{"name":"2008 IEEE 10th Workshop on Multimedia Signal Processing","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124158565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-11-05DOI: 10.1109/MMSP.2008.4665157
A. Rizzi, Nicola Maurizio Buccino, M. Panella, A. Uncini
This paper deals with the musical genre classification problem, starting from a set of features extracted directly from MPEG-1 layer III compressed audio data. The automatic classification of compressed audio signals into a short hierarchy of musical genres is explored. More specifically, three feature sets for representing timbre, rhythmic content and energy content are proposed for a four leafs tree genre hierarchy. The adopted set of features are computed from the spectral information available in the MPEG decoding stage. The performance and relative importance of the proposed approach is investigated by training a classification model using the audio collections proposed in musical genre contests. We also used an optimization strategy based on genetic algorithms. The results are comparable to those obtained by PCM-based musical genre classification systems.
{"title":"Genre classification of compressed audio data","authors":"A. Rizzi, Nicola Maurizio Buccino, M. Panella, A. Uncini","doi":"10.1109/MMSP.2008.4665157","DOIUrl":"https://doi.org/10.1109/MMSP.2008.4665157","url":null,"abstract":"This paper deals with the musical genre classification problem, starting from a set of features extracted directly from MPEG-1 layer III compressed audio data. The automatic classification of compressed audio signals into a short hierarchy of musical genres is explored. More specifically, three feature sets for representing timbre, rhythmic content and energy content are proposed for a four leafs tree genre hierarchy. The adopted set of features are computed from the spectral information available in the MPEG decoding stage. The performance and relative importance of the proposed approach is investigated by training a classification model using the audio collections proposed in musical genre contests. We also used an optimization strategy based on genetic algorithms. The results are comparable to those obtained by PCM-based musical genre classification systems.","PeriodicalId":402287,"journal":{"name":"2008 IEEE 10th Workshop on Multimedia Signal Processing","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123997947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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