Biography
Marco Cagnazzo obtained the Laurea (equivalent to the M.S.) degree in Telecommunication Engineering from the Federico II University (Napoli, Italy) in 2002 and the Ph.D. degree in Information and Communication Technology from the Federico II University and the University of Nice-Sophia Antipolis (France) in 2005, defending a doctoral thesis entitled “Wavelet transform and three-dimensional data compression”.
He obtained research grants from the CNIT national laboratory of multimedia communication and from the Centro Regionale di Competenze sull’ICT, and has been a post-doc fellow with the team CReATIVe at the I3S laboratory in Sophia Antipolis (France). Marco Cagnazzo has been a full professor at Telecom-Paris since December 2018, within the Multimedia team where he arrived as maître de conférences (roughly equivalent to associate professor) in 2008. He has achieved the Habilitation à Diriger des Recherches de l’Université Pierre et Marie Curie (Paris) in September 2013. He has been responsible for the Multimedia team from December 2015 to September 2021. Since December 2021 he is an Associate Professor at the University of Padua and an Invited Full Professor at Telecom-Paris.
Marco Cagnazzo has been an Associate Editor for IEEE Transactions on Circuits and Systems for Video Technology and for IEEE Signal Prcessing Letters and is Area Editor for Elsevier Signal Processing: Image Communication. Since 2017, he is a member of the IEEE SPS Technical Committee on Image, Video, and Multidimensional Signal Processing (IVMSP) and of the board of the main French society on signal processing, the GRETSI (Groupe de Recherche sur le Traitement du Signal et des Images).
Moreover, he regularly serves as a reviewer for several journals (among which IEEE Transactions on Image Processing, IEEE Transactions on Circuits and Systems for Video Technology, and IEEE Transactions on Signal Processing), and as reviewer and/or area chair for such conferences as IEEE ICIP, IEEE ICASSP, Eurasip EUSIPCO, IEEE MMSP, IEEE ICME.
He is IEEE Senior Member since February 2011.
He has been on the organizing committees of the 2010 IEEE International Workshop MMSP (Electronic Media Chair) and of the European Workshop on Visual Information Processing EUVIP (Local Arrangement). Moreover, he is Publicity Chair for EUSIPCO 2012 (Bucharest) and Award Chair for ICIP 2014 (Paris).
Marco Cagnazzo speaks Italian (his mother tongue), English, and French.
Research areas
Publications
2010
Petrazzuoli, G.; Cagnazzo, M.; Pesquet-Popescu, B.
High order motion interpolation for side information improvement in DVC Conference
ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing – Proceedings, Institute of Electrical and Electronics Engineers Inc., 2010, ISBN: 978-1-4244-4295-9.
@conference{ 11577_3469512,
title = {High order motion interpolation for side information improvement in DVC},
author = { G. Petrazzuoli and M. Cagnazzo and B. Pesquet-Popescu},
doi = {10.1109/ICASSP.2010.5496075},
isbn = {978-1-4244-4295-9},
year = {2010},
date = {2010-01-01},
booktitle = {ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings},
pages = {2342--2345},
publisher = {Institute of Electrical and Electronics Engineers Inc.},
abstract = {A key step in distributed video coding is the generation of the side information (SI) i.e. the estimation of the Wyner-Ziv frame (WZF). This step is also frequently called image interpolation. State-of-the-art techniques perform a motion estimation between adjacent key frames (KFs) and linear interpolation in order to assess object positions in the WZF, and then the SI is produced by motion compensating the KFs. However the uniform motion model underlying this approach is not always able to produce a satisfying estimation of the motion, which can result in a low SI quality. In this paper we propose a new method for the generation of SI, based on higher order motion interpolation. We use more than two KFs to estimate the position of the current WZF block, which allows us to correctly estimate more complex motion (such as, for example, uniform accelerated motion). We performed a number of tests for the fine tuning of the parameters of the method. Our experiments show that the new interpolation technique has a small computational cost increase with respect to state of the art, but provides remarkably better performance with up to 0.5 dB of PSNR improvement in SI quality. Moreover the proposed method performs consistently well for several GOP sizes. ©2010 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
A key step in distributed video coding is the generation of the side information (SI) i.e. the estimation of the Wyner-Ziv frame (WZF). This step is also frequently called image interpolation. State-of-the-art techniques perform a motion estimation between adjacent key frames (KFs) and linear interpolation in order to assess object positions in the WZF, and then the SI is produced by motion compensating the KFs. However the uniform motion model underlying this approach is not always able to produce a satisfying estimation of the motion, which can result in a low SI quality. In this paper we propose a new method for the generation of SI, based on higher order motion interpolation. We use more than two KFs to estimate the position of the current WZF block, which allows us to correctly estimate more complex motion (such as, for example, uniform accelerated motion). We performed a number of tests for the fine tuning of the parameters of the method. Our experiments show that the new interpolation technique has a small computational cost increase with respect to state of the art, but provides remarkably better performance with up to 0.5 dB of PSNR improvement in SI quality. Moreover the proposed method performs consistently well for several GOP sizes. ©2010 IEEE.
Greco, C.; Cagnazzo, M.; Pesquet-Popescu, B.
H.264-based multiple description coding using motion compensated temporal interpolation Conference
2010 IEEE 12th International Workshop on Multimedia Signal Processing (MMSP), 2010, ISBN: 978-1-4244-8110-1.
@conference{ 11577_3469517,
title = {H.264-based multiple description coding using motion compensated temporal interpolation},
author = { C. Greco and M. Cagnazzo and B. Pesquet-Popescu},
doi = {10.1109/MMSP.2010.5662026},
isbn = {978-1-4244-8110-1},
year = {2010},
date = {2010-01-01},
booktitle = {2010 IEEE 12th International Workshop on Multimedia Signal Processing (MMSP)},
pages = {239--244},
abstract = {Multiple description coding is a framework adapted to noisy transmission environments. In this work, we use H.264 to create two descriptions of a video sequence, each of them assuring a minimum quality level. If both of them are received, a suitable algorithm is used to produce an improved quality sequence. The key technique is a temporal image interpolation using motion compensation, inspired to the distributed video coding context. The interpolated image blocks are weighted with the received blocks obtained from the other description. The optimal weights are computed at the encoder and efficiently sent to the decoder as side information. The proposed technique shows a remarkable gain for central decoding with respect to similar methods available in the state of the art. ©2010 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Multiple description coding is a framework adapted to noisy transmission environments. In this work, we use H.264 to create two descriptions of a video sequence, each of them assuring a minimum quality level. If both of them are received, a suitable algorithm is used to produce an improved quality sequence. The key technique is a temporal image interpolation using motion compensation, inspired to the distributed video coding context. The interpolated image blocks are weighted with the received blocks obtained from the other description. The optimal weights are computed at the encoder and efficiently sent to the decoder as side information. The proposed technique shows a remarkable gain for central decoding with respect to similar methods available in the state of the art. ©2010 IEEE.
Petrazzuoli, G.; Cagnazzo, M.; Pesquet-Popescu, B.
Fast and efficient side information generation in distributed video coding by using dense motion representations Conference
European Signal Processing Conference, 2010.
@conference{ 11577_3471544,
title = {Fast and efficient side information generation in distributed video coding by using dense motion representations},
author = { G. Petrazzuoli and M. Cagnazzo and B. Pesquet-Popescu},
year = {2010},
date = {2010-01-01},
booktitle = {European Signal Processing Conference},
pages = {2156--2160},
abstract = {Distributed video coding (DVC) does not demand motion estimation (ME) and compensation (MC) at the encoder, but only at the decoder and so it is more suitable for applications that require a simple encoder, like wireless sensor networks. In DVC the video sequence is split into Key Frames (KFs) and Wyner-Ziv Frames (WZFs): the first are intra-coded and the latter are coded by a channel code and only the parity bits are sent to the decoder. The KFs are available at the decoder, while we need to estimate the WZF and correct this estimation with parity bits. One critical step is the estimation of the WZF. The method of the state of the art, with which we compare, is given by DISCOVER. It estimates the WZF by linear interpolating the two adjacent KFs. We propose a higher order motion interpolation for WZF estimation by using four KFs. Due to the high computational efforts, we propose also a fast algorithm that halves the complexity of the previous method. We note that the results of the fast method are comparable with the original one. An other proposal is to increase the density of the motion vector field in order to improve the estimation of the WZF. © EURASIP, 2010.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Distributed video coding (DVC) does not demand motion estimation (ME) and compensation (MC) at the encoder, but only at the decoder and so it is more suitable for applications that require a simple encoder, like wireless sensor networks. In DVC the video sequence is split into Key Frames (KFs) and Wyner-Ziv Frames (WZFs): the first are intra-coded and the latter are coded by a channel code and only the parity bits are sent to the decoder. The KFs are available at the decoder, while we need to estimate the WZF and correct this estimation with parity bits. One critical step is the estimation of the WZF. The method of the state of the art, with which we compare, is given by DISCOVER. It estimates the WZF by linear interpolating the two adjacent KFs. We propose a higher order motion interpolation for WZF estimation by using four KFs. Due to the high computational efforts, we propose also a fast algorithm that halves the complexity of the previous method. We note that the results of the fast method are comparable with the original one. An other proposal is to increase the density of the motion vector field in order to improve the estimation of the WZF. © EURASIP, 2010.
Abid, M.; Kieffer, M.; Cagnazzo, M.; Pesquet-Popescu, B.
Robust decoding of a 3D-escot bitstream transmitted over a noisy channel Conference
Proceedings – International Conference on Image Processing, ICIP, 2010, ISBN: 978-1-4244-7992-4.
@conference{ 11577_3471470,
title = {Robust decoding of a 3D-escot bitstream transmitted over a noisy channel},
author = { M. Abid and M. Kieffer and M. Cagnazzo and B. Pesquet-Popescu},
doi = {10.1109/ICIP.2010.5651795},
isbn = {978-1-4244-7992-4},
year = {2010},
date = {2010-01-01},
booktitle = {Proceedings - International Conference on Image Processing, ICIP},
pages = {473--476},
abstract = {In this paper, we propose a joint source-channel (JSC) decoding scheme for 3D ESCOT-based video coders, such as Vidwav. The embedded bitstream generated by such coders is very sensitive to transmission errors unavoidable on wireless channels. The proposed JSC decoder employs the residual redundancy left in the bitstream by the source coder combined with bit reliability information provided by the channel or channel decoder to correct transmission errors. When considering an AWGN channel, the performance gains are in average 4 dB in terms of PSNR of the reconstructed frames, and 0.7 dB in terms of channel SNR. When considering individual frames, the obtained gain is up to 15 dB in PSNR. © 2010 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
In this paper, we propose a joint source-channel (JSC) decoding scheme for 3D ESCOT-based video coders, such as Vidwav. The embedded bitstream generated by such coders is very sensitive to transmission errors unavoidable on wireless channels. The proposed JSC decoder employs the residual redundancy left in the bitstream by the source coder combined with bit reliability information provided by the channel or channel decoder to correct transmission errors. When considering an AWGN channel, the performance gains are in average 4 dB in terms of PSNR of the reconstructed frames, and 0.7 dB in terms of channel SNR. When considering individual frames, the obtained gain is up to 15 dB in PSNR. © 2010 IEEE.
Maugey, T.; Yaacoub, C.; Farah, J.; Cagnazzo, M.; Pesquet-Popescu, B.
Side information enhancement using an adaptive hash-based genetic algorithm in a Wyner-Ziv context Conference
2010 IEEE International Workshop on Multimedia Signal Processing, MMSP2010, 2010, ISBN: 978-1-4244-8110-1.
@conference{ 11577_3469808,
title = {Side information enhancement using an adaptive hash-based genetic algorithm in a Wyner-Ziv context},
author = { T. Maugey and C. Yaacoub and J. Farah and M. Cagnazzo and B. Pesquet-Popescu},
doi = {10.1109/MMSP.2010.5662036},
isbn = {978-1-4244-8110-1},
year = {2010},
date = {2010-01-01},
booktitle = {2010 IEEE International Workshop on Multimedia Signal Processing, MMSP2010},
pages = {298--302},
abstract = {Side information construction in Wyner-Ziv video coding is a sensible task which strongly influences the final rate-distortion performance of the scheme. This side information is usually generated through an interpolation of the previous and next images. Some of the zones of a scene however, such as the occlusions, cannot be estimated with other frames. In this paper we propose to avoid this problem by sending some hash information for these unpredictable zones of the image. The resulting algorithm is described and tested here. The obtained results show the advantages of using localized hash information for the high error zones in distributed video coding. ©2010 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Side information construction in Wyner-Ziv video coding is a sensible task which strongly influences the final rate-distortion performance of the scheme. This side information is usually generated through an interpolation of the previous and next images. Some of the zones of a scene however, such as the occlusions, cannot be estimated with other frames. In this paper we propose to avoid this problem by sending some hash information for these unpredictable zones of the image. The resulting algorithm is described and tested here. The obtained results show the advantages of using localized hash information for the high error zones in distributed video coding. ©2010 IEEE.
Cagnazzo, M.; Antonini, M.; Barlaud, M.
Mutual information-based context quantization Journal Article
In: SIGNAL PROCESSING-IMAGE COMMUNICATION, vol. 25, no. 1, pp. 64–74, 2010.
@article{ 11577_3469378,
title = {Mutual information-based context quantization},
author = { M. Cagnazzo and M. Antonini and M. Barlaud},
doi = {10.1016/j.image.2009.09.002},
year = {2010},
date = {2010-01-01},
journal = {SIGNAL PROCESSING-IMAGE COMMUNICATION},
volume = {25},
number = {1},
pages = {64--74},
abstract = {Context-based lossless coding suffers in many cases from the so-called context dilution problem, which arises when, in order to model high-order statistic dependencies among data, a large number of contexts is used. In this case the learning process cannot be fed with enough data, and so the probability estimation is not reliable. To avoid this problem, state-of-the-art algorithms for lossless image coding resort to context quantization (CQ) into a few conditioning states, whose statistics are easier to estimate in a reliable way. It has been early recognized that in order to achieve the best compression ratio, contexts have to be grouped according to a maximal mutual information criterion. This leads to quantization algorithms which are able to determine a local minimum of the coding cost in the general case, and even the global minimum in the case of binary-valued input. This paper surveys the CQ problem and provides a detailed analytical formulation of it, allowing to shed light on some details of the optimization process. As a consequence we find that state-of-the-art algorithms have a suboptimal step. The proposed approach allows a steeper path toward the cost function minimum. Moreover, some sufficient conditions are found that allow to find a globally optimal solution even when the input alphabet is not binary. Even though the paper mainly focuses on the theoretical aspects of CQ, a number of experiments to validate the proposed method have been performed (for the special case of segmentation map lossless coding), and encouraging results have been recorded. © 2009 Elsevier B.V. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Context-based lossless coding suffers in many cases from the so-called context dilution problem, which arises when, in order to model high-order statistic dependencies among data, a large number of contexts is used. In this case the learning process cannot be fed with enough data, and so the probability estimation is not reliable. To avoid this problem, state-of-the-art algorithms for lossless image coding resort to context quantization (CQ) into a few conditioning states, whose statistics are easier to estimate in a reliable way. It has been early recognized that in order to achieve the best compression ratio, contexts have to be grouped according to a maximal mutual information criterion. This leads to quantization algorithms which are able to determine a local minimum of the coding cost in the general case, and even the global minimum in the case of binary-valued input. This paper surveys the CQ problem and provides a detailed analytical formulation of it, allowing to shed light on some details of the optimization process. As a consequence we find that state-of-the-art algorithms have a suboptimal step. The proposed approach allows a steeper path toward the cost function minimum. Moreover, some sufficient conditions are found that allow to find a globally optimal solution even when the input alphabet is not binary. Even though the paper mainly focuses on the theoretical aspects of CQ, a number of experiments to validate the proposed method have been performed (for the special case of segmentation map lossless coding), and encouraging results have been recorded. © 2009 Elsevier B.V. All rights reserved.
Cagnazzo, M.; Pesquet-Popescu, B.
Introducing differential motion estimation into hybrid video coders Conference
Proceedings of SPIE – The International Society for Optical Engineering, vol. 7744, 2010.
@conference{ 11577_3471473,
title = {Introducing differential motion estimation into hybrid video coders},
author = { M. Cagnazzo and B. Pesquet-Popescu},
doi = {10.1117/12.863825},
year = {2010},
date = {2010-01-01},
booktitle = {Proceedings of SPIE - The International Society for Optical Engineering},
volume = {7744},
abstract = {Differential motion estimation produces dense motion vector fields which are far too demanding in terms of coding rate in order to be used in video coding. However, a pel-recursive technique like that introduced by Cafforio and Rocca can be modified in order to work using only the information available at the decoder side. This allows to improve the motion vectors produced in the classical predictive modes of H.264. In this paper we describe the modification needed in order to introduce a differential motion estimation method into the H.264 codec. Experimental results will validate a coding mode, opening new perspectives in using differential-based motion estimation techniques into classical hybrid codecs. © 2010 SPIE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Differential motion estimation produces dense motion vector fields which are far too demanding in terms of coding rate in order to be used in video coding. However, a pel-recursive technique like that introduced by Cafforio and Rocca can be modified in order to work using only the information available at the decoder side. This allows to improve the motion vectors produced in the classical predictive modes of H.264. In this paper we describe the modification needed in order to introduce a differential motion estimation method into the H.264 codec. Experimental results will validate a coding mode, opening new perspectives in using differential-based motion estimation techniques into classical hybrid codecs. © 2010 SPIE.
Abid, M.; Cagnazzo, M.; Pesquet-Popescu, B.
Image denoising by adaptive lifting schemes Conference
2010 2nd European Workshop on Visual Information Processing, EUVIP2010, 2010, ISBN: 978-1-4244-7288-8.
@conference{ 11577_3471541,
title = {Image denoising by adaptive lifting schemes},
author = { M. Abid and M. Cagnazzo and B. Pesquet-Popescu},
doi = {10.1109/EUVIP.2010.5699143},
isbn = {978-1-4244-7288-8},
year = {2010},
date = {2010-01-01},
booktitle = {2010 2nd European Workshop on Visual Information Processing, EUVIP2010},
pages = {108--113},
abstract = {In this paper, we study the problem of image denoising by using an adaptive lifting scheme. Such a scheme can adapt itself well to the analyzed signal, which allows to keep important information for denoising applications. However, it results in a non-isometric transform which can be an important limitation as most of the denoising approaches rely on the estimation of the noise energy in the subbands. In a previous work, it has been shown how to evaluate the subband energies of an uncorrelated signal, in the wavelet domain when using such an adaptive scheme. Based on this previous work, we propose in this paper an estimation of the noise energies in the subband and use it to perform image denoising. Experimental results illustrate that this approach is more effective, in image denoising, than the classical non adaptive lifting schemes both considering perceptual and non perceptual image quality measures. ©2010 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
In this paper, we study the problem of image denoising by using an adaptive lifting scheme. Such a scheme can adapt itself well to the analyzed signal, which allows to keep important information for denoising applications. However, it results in a non-isometric transform which can be an important limitation as most of the denoising approaches rely on the estimation of the noise energy in the subbands. In a previous work, it has been shown how to evaluate the subband energies of an uncorrelated signal, in the wavelet domain when using such an adaptive scheme. Based on this previous work, we propose in this paper an estimation of the noise energies in the subband and use it to perform image denoising. Experimental results illustrate that this approach is more effective, in image denoising, than the classical non adaptive lifting schemes both considering perceptual and non perceptual image quality measures. ©2010 IEEE.
Petrazzuoli, G.; Maugey, T.; Cagnazzo, M.; Pesquet-Popescu, B.
Side information refinement for long duration GOPs in DVC Conference
2010 IEEE International Workshop on Multimedia Signal Processing, MMSP2010, 2010, ISBN: 978-1-4244-8110-1.
@conference{ 11577_3469696,
title = {Side information refinement for long duration GOPs in DVC},
author = { G. Petrazzuoli and T. Maugey and M. Cagnazzo and B. Pesquet-Popescu},
doi = {10.1109/MMSP.2010.5662038},
isbn = {978-1-4244-8110-1},
year = {2010},
date = {2010-01-01},
booktitle = {2010 IEEE International Workshop on Multimedia Signal Processing, MMSP2010},
pages = {309--314},
abstract = {Side information generation is a critical step in distributed video coding systems. This is performed by using motion compensated temporal interpolation between two or more key frames (KFs). However, when the temporal distance between key frames increases (i.e. when the GOP size becomes large), the linear interpolation becomes less effective. In a previous work we showed that this problem can be mitigated by using high order interpolation. Now, in the case of long duration GOP, state-of-the-art algorithms propose a hierarchical algorithm for side information generation. By using this procedure, the quality of the central interpolated image in a GOP is consistently worse than images closer to the KFs. In this paper we propose a refinement of the central WZFs by higher order interpolation of the already decoded WZFs, that are closer to the WZF to be estimated. So we reduce the fluctuation of side information quality, with a beneficial impact on final rate-distortion characteristics of the system. The experimental results show an improvement on the SI up to 2.71 dB with respect the state-of-the-art and a global improvement of the PSNR on the decoded frames up to 0.71 dB and a bit rate reduction up to 15 %. ©2010 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Side information generation is a critical step in distributed video coding systems. This is performed by using motion compensated temporal interpolation between two or more key frames (KFs). However, when the temporal distance between key frames increases (i.e. when the GOP size becomes large), the linear interpolation becomes less effective. In a previous work we showed that this problem can be mitigated by using high order interpolation. Now, in the case of long duration GOP, state-of-the-art algorithms propose a hierarchical algorithm for side information generation. By using this procedure, the quality of the central interpolated image in a GOP is consistently worse than images closer to the KFs. In this paper we propose a refinement of the central WZFs by higher order interpolation of the already decoded WZFs, that are closer to the WZF to be estimated. So we reduce the fluctuation of side information quality, with a beneficial impact on final rate-distortion characteristics of the system. The experimental results show an improvement on the SI up to 2.71 dB with respect the state-of-the-art and a global improvement of the PSNR on the decoded frames up to 0.71 dB and a bit rate reduction up to 15 %. ©2010 IEEE.
2009
Cagnazzo, M.; Agostini, M. A.; Antonini, M.; Laroche, G.; Jung, J.
Motion vector quantization for efficient low bit-rate video coding Conference
Proceedings of SPIE – The International Society for Optical Engineering, vol. 7257, 2009.
@conference{ 11577_3469682,
title = {Motion vector quantization for efficient low bit-rate video coding},
author = { M. Cagnazzo and M. A. Agostini and M. Antonini and G. Laroche and J. Jung},
doi = {10.1117/12.805857},
year = {2009},
date = {2009-01-01},
booktitle = {Proceedings of SPIE - The International Society for Optical Engineering},
volume = {7257},
abstract = {The most recent video coding standard H.264 achieves excellent compression performances at many different bit-rates. However, it has been noted that, at very high compression ratios, a large part of the available coding resources is only used to code motion vectors. This can lead to a suboptimal coding performance. This paper introduces a new coding mode for a H.264-based video coder, using quantized motion vector (QMV) to improve the management of the resource allocation between motion information and transform coefficients. Several problems have to be faced with in order to get an efficient implementation of QMV techniques, yet encouraging results are reported in preliminary tests, allowing to improve the performances of H.264 at low bit-rates over Several sequences. © 2009 SPIE-IS&T.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The most recent video coding standard H.264 achieves excellent compression performances at many different bit-rates. However, it has been noted that, at very high compression ratios, a large part of the available coding resources is only used to code motion vectors. This can lead to a suboptimal coding performance. This paper introduces a new coding mode for a H.264-based video coder, using quantized motion vector (QMV) to improve the management of the resource allocation between motion information and transform coefficients. Several problems have to be faced with in order to get an efficient implementation of QMV techniques, yet encouraging results are reported in preliminary tests, allowing to improve the performances of H.264 at low bit-rates over Several sequences. © 2009 SPIE-IS&T.
Corrado, S.; Agostini, M. A.; Cagnazzo, M.; Antonini, M.; Laroche, G.; Jung, J.
Improving H.264 performances by quantization of motion vectors Conference
2009 Picture Coding Symposium, PCS 2009, 2009, ISBN: 978-1-4244-4593-6.
@conference{ 11577_3469688,
title = {Improving H.264 performances by quantization of motion vectors},
author = { S. Corrado and M. A. Agostini and M. Cagnazzo and M. Antonini and G. Laroche and J. Jung},
doi = {10.1109/PCS.2009.5167401},
isbn = {978-1-4244-4593-6},
year = {2009},
date = {2009-01-01},
booktitle = {2009 Picture Coding Symposium, PCS 2009},
pages = {1--4},
abstract = {The coding resources used for motion vectors (MVs) can attain quite high ratios even in the case of efficient video coders like H.264, and this can easily lead to suboptimal rate-distortion performance. In a previous paper, we proposed a new coding mode for H.264 based on the quantization of motion vectors (QMV). We only considered the case of 16×16 partitions for motion estimation and compensation. That method allowed us to obtain an improved trade-off in the resource allocation between vectors and coefficients, and to achieve better rate-distortion performances with respect to H.264. In this paper, we build on the proposed QMV coding mode, extending it to the case of macroblock partition into smaller blocks. This issue requires solving some problems mainly related to the motion vector coding. We show how this task can be performed efficiently in our framework, obtaining further improvements over the standard coding technique.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The coding resources used for motion vectors (MVs) can attain quite high ratios even in the case of efficient video coders like H.264, and this can easily lead to suboptimal rate-distortion performance. In a previous paper, we proposed a new coding mode for H.264 based on the quantization of motion vectors (QMV). We only considered the case of 16×16 partitions for motion estimation and compensation. That method allowed us to obtain an improved trade-off in the resource allocation between vectors and coefficients, and to achieve better rate-distortion performances with respect to H.264. In this paper, we build on the proposed QMV coding mode, extending it to the case of macroblock partition into smaller blocks. This issue requires solving some problems mainly related to the motion vector coding. We show how this task can be performed efficiently in our framework, obtaining further improvements over the standard coding technique.
Maugey, T.; Miled, W.; Cagnazzo, M.; Pesquet-Popescu, B.
Fusion schemes for multiview distributed video coding Conference
European Signal Processing Conference, 2009.
@conference{ 11577_3471471,
title = {Fusion schemes for multiview distributed video coding},
author = { T. Maugey and W. Miled and M. Cagnazzo and B. Pesquet-Popescu},
year = {2009},
date = {2009-01-01},
booktitle = {European Signal Processing Conference},
pages = {559--563},
abstract = {Distributed video coding performances strongly depend on the side information quality, built at the decoder. In multi-view schemes, correlations in both time and view directions are exploited, obtaining in general two estimations that need to be merged. This step, called fusion, greatly affects the performance of the coding scheme; however, the existing methods do not achieve acceptable performances in all cases, especially when one of the estimations is not of good quality, since in this case they are not able to discard it. This paper provides a detailed review of existing fusion methods between temporal and inter-view side information, and proposes new promising techniques. Experimental results show that these methods have good performances in a variety of configurations. © EURASIP, 2009.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Distributed video coding performances strongly depend on the side information quality, built at the decoder. In multi-view schemes, correlations in both time and view directions are exploited, obtaining in general two estimations that need to be merged. This step, called fusion, greatly affects the performance of the coding scheme; however, the existing methods do not achieve acceptable performances in all cases, especially when one of the estimations is not of good quality, since in this case they are not able to discard it. This paper provides a detailed review of existing fusion methods between temporal and inter-view side information, and proposes new promising techniques. Experimental results show that these methods have good performances in a variety of configurations. © EURASIP, 2009.
Parrilli, S.; Cagnazzo, M.; Pesquet-Popescu, B.
Estimation of quantization noise for adaptive-prediction lifting schemes Conference
2009 IEEE International Workshop on Multimedia Signal Processing, MMSP ’09, 2009, ISBN: 978-1-4244-4463-2.
@conference{ 11577_3469690,
title = {Estimation of quantization noise for adaptive-prediction lifting schemes},
author = { S. Parrilli and M. Cagnazzo and B. Pesquet-Popescu},
doi = {10.1109/MMSP.2009.5293262},
isbn = {978-1-4244-4463-2},
year = {2009},
date = {2009-01-01},
booktitle = {2009 IEEE International Workshop on Multimedia Signal Processing, MMSP '09},
pages = {1--6},
abstract = {The lifting scheme represents an easy way of implementing the wavelet transform and of constructing new content-adapted transforms. However, the adaptive version of lifting schemes can result in strongly non-isometric transforms. This can be a major limitation, since all most successful coding techniques rely on the distortion estimation in the transform domain. In this paper we focus on the problem of evaluating the reconstruction distortion (due to quantization noise) in the wavelet domain when a non-isometric adaptive-prediction lifting scheme is used. The problem arises since these transforms are nonlinear, and so common techniques for distortion evaluation cannot be used in this case. We circumvent the difficulty by computing an equivalent time-varying linear filter, for which it is possible to generalize the distortion computation technique. In addition to the theoretical formulation of the distortion estimation, in this paper we provide experimental results proving the reliability of this estimation, and the consequent improvement of RD performance, thanks to a more effective resource allocation which can be performed in the transform domain. © 2009 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The lifting scheme represents an easy way of implementing the wavelet transform and of constructing new content-adapted transforms. However, the adaptive version of lifting schemes can result in strongly non-isometric transforms. This can be a major limitation, since all most successful coding techniques rely on the distortion estimation in the transform domain. In this paper we focus on the problem of evaluating the reconstruction distortion (due to quantization noise) in the wavelet domain when a non-isometric adaptive-prediction lifting scheme is used. The problem arises since these transforms are nonlinear, and so common techniques for distortion evaluation cannot be used in this case. We circumvent the difficulty by computing an equivalent time-varying linear filter, for which it is possible to generalize the distortion computation technique. In addition to the theoretical formulation of the distortion estimation, in this paper we provide experimental results proving the reliability of this estimation, and the consequent improvement of RD performance, thanks to a more effective resource allocation which can be performed in the transform domain. © 2009 IEEE.
Daribo, I.; Kaaniche, M.; Miled, W.; Cagnazzo, M.; Pesquet-Popescu, B.
Dense disparity estimation in multiview video coding Conference
2009 IEEE International Workshop on Multimedia Signal Processing, MMSP ’09, 2009, ISBN: 978-1-4244-4463-2.
@conference{ 11577_3471475,
title = {Dense disparity estimation in multiview video coding},
author = { I. Daribo and M. Kaaniche and W. Miled and M. Cagnazzo and B. Pesquet-Popescu},
doi = {10.1109/MMSP.2009.5293289},
isbn = {978-1-4244-4463-2},
year = {2009},
date = {2009-01-01},
booktitle = {2009 IEEE International Workshop on Multimedia Signal Processing, MMSP '09},
pages = {1--6},
abstract = {Multiview video coding is an emerging application where, in addition to classical temporal prediction, an efficient disparity prediction should be performed in order to achieve the best compression performance. A popular coder is the multiview video coding (MVC) extension of H.264/AVC, which uses a block-based disparity estimation (just like temporal prediction in H.264/AVC). In this paper, we propose to improve the MVC extension by using a dense estimation method that generates a smooth disparity map with ideally infinite precision. The obtained disparity is then segmented and efficiently encoded by using a rate-distortion optimization technique. Experimental results show that significant gains can be obtained compared to the block-based disparity estimation technique used in the MVC extension. © 2009 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Multiview video coding is an emerging application where, in addition to classical temporal prediction, an efficient disparity prediction should be performed in order to achieve the best compression performance. A popular coder is the multiview video coding (MVC) extension of H.264/AVC, which uses a block-based disparity estimation (just like temporal prediction in H.264/AVC). In this paper, we propose to improve the MVC extension by using a dense estimation method that generates a smooth disparity map with ideally infinite precision. The obtained disparity is then segmented and efficiently encoded by using a rate-distortion optimization technique. Experimental results show that significant gains can be obtained compared to the block-based disparity estimation technique used in the MVC extension. © 2009 IEEE.
Cagnazzo, M.; Maugey, T.; Pesquet-Popescu, B.
A differential motion estimation method for image interpolation in distributed video coding Conference
ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing – Proceedings, 2009, ISBN: 978-1-4244-2353-8.
@conference{ 11577_3469689,
title = {A differential motion estimation method for image interpolation in distributed video coding},
author = { M. Cagnazzo and T. Maugey and B. Pesquet-Popescu},
doi = {10.1109/ICASSP.2009.4959970},
isbn = {978-1-4244-2353-8},
year = {2009},
date = {2009-01-01},
booktitle = {ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings},
pages = {1861--1864},
abstract = {Motion estimation methods based on differential techniques proved to be very useful in the context of video analysis, but have a limited employment in classical video compression because, though accurate, the dense motion vector field they produce requires too much coding resource and computational effort. On the contrary, this kind of algorithm could be useful in the framework of distributed video coding (DVC). In this paper we propose a differential motion estimation algorithm which can run at the decoder in a DVC scheme, without requiring any increase in coding rate. This algorithm allows a performance improvement in image interpolation with respect to state-of-the-art algorithms. ©2009 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Motion estimation methods based on differential techniques proved to be very useful in the context of video analysis, but have a limited employment in classical video compression because, though accurate, the dense motion vector field they produce requires too much coding resource and computational effort. On the contrary, this kind of algorithm could be useful in the framework of distributed video coding (DVC). In this paper we propose a differential motion estimation algorithm which can run at the decoder in a DVC scheme, without requiring any increase in coding rate. This algorithm allows a performance improvement in image interpolation with respect to state-of-the-art algorithms. ©2009 IEEE.
Tizon, N.; Pesquet-Popescu, B.; Cagnazzo, M.
Adaptive video streaming with long term feedbacks Conference
Proceedings – International Conference on Image Processing, ICIP, IEEE Computer Society, 2009, ISBN: 978-1-4244-5654-3.
@conference{ 11577_3471543,
title = {Adaptive video streaming with long term feedbacks},
author = { N. Tizon and B. Pesquet-Popescu and M. Cagnazzo},
doi = {10.1109/ICIP.2009.5414022},
isbn = {978-1-4244-5654-3},
year = {2009},
date = {2009-01-01},
booktitle = {Proceedings - International Conference on Image Processing, ICIP},
pages = {949--952},
publisher = {IEEE Computer Society},
abstract = {This paper proposes a video streaming system optimizing resource utilization when the media server only disposes of long term feedbacks from the client. Based on a partial knowledge of the network, we developed a scheduling algorithm that exploits the scalable video coding (SVC) properties to estimate packets importance and that takes into account packet delay dependencies to better anticipate congestion situations. Compared to more conventional streaming systems, experimental results show that our approach allows to better face network condition degradation like bandwidth reduction or packet error rate increase. ©2009 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
This paper proposes a video streaming system optimizing resource utilization when the media server only disposes of long term feedbacks from the client. Based on a partial knowledge of the network, we developed a scheduling algorithm that exploits the scalable video coding (SVC) properties to estimate packets importance and that takes into account packet delay dependencies to better anticipate congestion situations. Compared to more conventional streaming systems, experimental results show that our approach allows to better face network condition degradation like bandwidth reduction or packet error rate increase. ©2009 IEEE.
Miled, W.; Maugey, T.; Cagnazzo, M.; Pesquet-Popescu, B.
Image interpolation with dense disparity estimation in multiview distributed video coding Conference
2009 3rd ACM/IEEE International Conference on Distributed Smart Cameras, ICDSC 2009, 2009.
@conference{ 11577_3469691,
title = {Image interpolation with dense disparity estimation in multiview distributed video coding},
author = { W. Miled and T. Maugey and M. Cagnazzo and B. Pesquet-Popescu},
doi = {10.1109/ICDSC.2009.5289344},
year = {2009},
date = {2009-01-01},
booktitle = {2009 3rd ACM/IEEE International Conference on Distributed Smart Cameras, ICDSC 2009},
pages = {1--6},
abstract = {This paper deals with the side information (SI) gen- eration problem in multiview distributed video coding (MDVC). For inter-view interpolation, we propose a novel dense disparity estimation (DE) approach combined with a popular distributed video coding (DVC) technique. As disparity vectors are computed at the decoder side, and no coding rate is needed to transmit them, dense estimation techniques are made possible, leading to improved results without requiring high coding resources. Experimental results show that the proposed interpolation tech- nique can achieve up to 2.0 dB improvement in SI reconstruction performance, when compared to state-of-the-art DVC techniques. © 2009 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
This paper deals with the side information (SI) gen- eration problem in multiview distributed video coding (MDVC). For inter-view interpolation, we propose a novel dense disparity estimation (DE) approach combined with a popular distributed video coding (DVC) technique. As disparity vectors are computed at the decoder side, and no coding rate is needed to transmit them, dense estimation techniques are made possible, leading to improved results without requiring high coding resources. Experimental results show that the proposed interpolation tech- nique can achieve up to 2.0 dB improvement in SI reconstruction performance, when compared to state-of-the-art DVC techniques. © 2009 IEEE.
Cagnazzo, M.; Miled, W.; Maugey, T.; Pesquet-Popescu, B.
Image interpolation with edge-preserving differential motion refinement Conference
Proceedings – International Conference on Image Processing, ICIP, IEEE Computer Society, 2009, ISBN: 978-1-4244-5654-3.
@conference{ 11577_3471468,
title = {Image interpolation with edge-preserving differential motion refinement},
author = { M. Cagnazzo and W. Miled and T. Maugey and B. Pesquet-Popescu},
doi = {10.1109/ICIP.2009.5414204},
isbn = {978-1-4244-5654-3},
year = {2009},
date = {2009-01-01},
booktitle = {Proceedings - International Conference on Image Processing, ICIP},
pages = {361--364},
publisher = {IEEE Computer Society},
abstract = {Motion estimation (ME) methods based on differential techniques provide useful information for video analysis, and moreover it is relatively easy to embed into them regularity constraints enforcing for example, contour preservation. On the other hand, these techniques are rarely employed for video compression since, though accurate, the dense motion vector field (MVF) they produce requires too much coding resource and computational effort. However, this kind of algorithm could be useful in the framework of distributed video coding (DVC), where the motion vector are computed at the decoder side, so that no bit-rate is needed to transmit them. Moreover usually the decoder has enough computational power to face with the increased complexity of differential ME. In this paper we introduce a new image interpolation algorithm to be used in the context of DVC. This algorithm combines a popular DVC technique with differential ME. We adapt a pel-recursive differential ME algorithm to the DVC context; moreover we insert a regularity constraint which allows more consistent MVFs. The experimental results are encouraging: the quality of interpolated images is improved of up to 1.1 dB w.r.t. to state-of-the-art techniques. These results prove to be consistent when we use different GOP sizes. ©2009 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Motion estimation (ME) methods based on differential techniques provide useful information for video analysis, and moreover it is relatively easy to embed into them regularity constraints enforcing for example, contour preservation. On the other hand, these techniques are rarely employed for video compression since, though accurate, the dense motion vector field (MVF) they produce requires too much coding resource and computational effort. However, this kind of algorithm could be useful in the framework of distributed video coding (DVC), where the motion vector are computed at the decoder side, so that no bit-rate is needed to transmit them. Moreover usually the decoder has enough computational power to face with the increased complexity of differential ME. In this paper we introduce a new image interpolation algorithm to be used in the context of DVC. This algorithm combines a popular DVC technique with differential ME. We adapt a pel-recursive differential ME algorithm to the DVC context; moreover we insert a regularity constraint which allows more consistent MVFs. The experimental results are encouraging: the quality of interpolated images is improved of up to 1.1 dB w.r.t. to state-of-the-art techniques. These results prove to be consistent when we use different GOP sizes. ©2009 IEEE.
2008
Parrilli, S.; Cagnazzo, M.; Pesquet-Popescu, B.
Distortion evaluation in transform domain for adaptive lifting schemes Conference
Proceedings of the 2008 IEEE 10th Workshop on Multimedia Signal Processing, MMSP 2008, 2008, ISBN: 978-1-4244-2294-4.
@conference{ 11577_3471472,
title = {Distortion evaluation in transform domain for adaptive lifting schemes},
author = { S. Parrilli and M. Cagnazzo and B. Pesquet-Popescu},
doi = {10.1109/MMSP.2008.4665075},
isbn = {978-1-4244-2294-4},
year = {2008},
date = {2008-01-01},
booktitle = {Proceedings of the 2008 IEEE 10th Workshop on Multimedia Signal Processing, MMSP 2008},
pages = {200--205},
abstract = {In this paper we study the problem of evaluating the reconstruction distortion in the wavelet domain when adaptive lifting schemes (ALS) are used for the direct and inverse transform. The distortion evaluation is necessary in order to perform efficient resource allocation over the transform coefficients. ALS is a non-linear transformation, which prevents using common techniques for distortion evaluation. However we show the equivalence of this non-linear scheme with a time-varying linear filter, and we generalize the distortion computation technique to it. Experiments show that the proposed method allows a reliable estimation of the distortion in the transform domain. This results in improved coding performance. © 2008 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
In this paper we study the problem of evaluating the reconstruction distortion in the wavelet domain when adaptive lifting schemes (ALS) are used for the direct and inverse transform. The distortion evaluation is necessary in order to perform efficient resource allocation over the transform coefficients. ALS is a non-linear transformation, which prevents using common techniques for distortion evaluation. However we show the equivalence of this non-linear scheme with a time-varying linear filter, and we generalize the distortion computation technique to it. Experiments show that the proposed method allows a reliable estimation of the distortion in the transform domain. This results in improved coding performance. © 2008 IEEE.
2007
Cagnazzo, M.; Parrilli, S.; Poggi, G.; Verdoliva, L.
Costs and advantages of object-based image coding with shape-adaptive wavelet transform Journal Article
In: EURASIP JOURNAL ON IMAGE AND VIDEO PROCESSING, vol. 2007, pp. 1–13, 2007.
@article{ 11577_3469523,
title = {Costs and advantages of object-based image coding with shape-adaptive wavelet transform},
author = { M. Cagnazzo and S. Parrilli and G. Poggi and L. Verdoliva},
doi = {10.1155/2007/78323},
year = {2007},
date = {2007-01-01},
journal = {EURASIP JOURNAL ON IMAGE AND VIDEO PROCESSING},
volume = {2007},
pages = {1--13},
abstract = {Object-based image coding is drawing a great attention for the many opportunities it offers to high-level applications. In terms of rate-distortion performance, however, its value is still uncertain, because the gains provided by an accurate image segmentation are balanced by the inefficiency of coding objects of arbitrary shape, with losses that depend on both the coding scheme and the object geometry. This work aims at measuring rate-distortion costs and gains for a wavelet-based shape-adaptive encoder similar to the shape-adaptive texture coder adopted in MPEG-4. The analysis of the rate-distortion curves obtained in several experiments provides insight about what performance gains and losses can be expected in various operative conditions and shows the potential of such an approach for image coding.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Object-based image coding is drawing a great attention for the many opportunities it offers to high-level applications. In terms of rate-distortion performance, however, its value is still uncertain, because the gains provided by an accurate image segmentation are balanced by the inefficiency of coding objects of arbitrary shape, with losses that depend on both the coding scheme and the object geometry. This work aims at measuring rate-distortion costs and gains for a wavelet-based shape-adaptive encoder similar to the shape-adaptive texture coder adopted in MPEG-4. The analysis of the rate-distortion curves obtained in several experiments provides insight about what performance gains and losses can be expected in various operative conditions and shows the potential of such an approach for image coding.
Cagnazzo, M.; Parrilli, S.; Poggi, G.; Verdoliva, L.
Improved class-based coding of multispectral images with shape-adaptive wavelet transform Journal Article
In: IEEE GEOSCIENCE AND REMOTE SENSING LETTERS, vol. 4, no. 4, pp. 566–570, 2007.
@article{ 11577_3469526,
title = {Improved class-based coding of multispectral images with shape-adaptive wavelet transform},
author = { M. Cagnazzo and S. Parrilli and G. Poggi and L. Verdoliva},
doi = {10.1109/LGRS.2007.900696},
year = {2007},
date = {2007-01-01},
journal = {IEEE GEOSCIENCE AND REMOTE SENSING LETTERS},
volume = {4},
number = {4},
pages = {566--570},
abstract = {In this letter, we improve the class-based transform-coding scheme proposed by Gelli and Poggi for the compression of multispectral images. The original spatial-coding tools, 1-D discrete cosine transform and scalar quantization, are replaced by shape-adaptive wavelet transform and set partitioning in hierarchical trees. Numerical experiments show that the improved technique outperforms the original one for medium- to high-quality compression and is consistently superior to all reference techniques. © 2007 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In this letter, we improve the class-based transform-coding scheme proposed by Gelli and Poggi for the compression of multispectral images. The original spatial-coding tools, 1-D discrete cosine transform and scalar quantization, are replaced by shape-adaptive wavelet transform and set partitioning in hierarchical trees. Numerical experiments show that the improved technique outperforms the original one for medium- to high-quality compression and is consistently superior to all reference techniques. © 2007 IEEE.
Cagnazzo, M.; Castaldo, F.; Andre, T.; Antonini, M.; Barlaud, M.
Optimal motion estimation for wavelet motion compensated video coding Journal Article
In: IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY, vol. 17, no. 7, pp. 907–911, 2007.
@article{ 11577_3469522,
title = {Optimal motion estimation for wavelet motion compensated video coding},
author = { M. Cagnazzo and F. Castaldo and T. Andre and M. Antonini and M. Barlaud},
doi = {10.1109/TCSVT.2007.897110},
year = {2007},
date = {2007-01-01},
journal = {IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY},
volume = {17},
number = {7},
pages = {907--911},
abstract = {Wavelet-based coding is emerging as a promising framework for efficient and scalable compression of video. Nevertheless, a number of basic tools currently employed in this field have been conceived for hybrid block-based transform coding. This is the case of motion estimation, which generally aims to minimize the energy or the absolute sum of prediction error. However, as wavelet video coders do not employ predictive coding, this is no longer an optimal approach. In this paper we study the problem of the theoretical optimal criterion for wavelet-based video coders, using coding gain as merit figure. A simple solution has been found for a peculiar but useful class of temporal filters. Experiments confirm that the optimally estimated vectors increase the coding gain as well as the performance of a complete video coder, but at the cost of an augmented complexity. © 2007 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Wavelet-based coding is emerging as a promising framework for efficient and scalable compression of video. Nevertheless, a number of basic tools currently employed in this field have been conceived for hybrid block-based transform coding. This is the case of motion estimation, which generally aims to minimize the energy or the absolute sum of prediction error. However, as wavelet video coders do not employ predictive coding, this is no longer an optimal approach. In this paper we study the problem of the theoretical optimal criterion for wavelet-based video coders, using coding gain as merit figure. A simple solution has been found for a peculiar but useful class of temporal filters. Experiments confirm that the optimally estimated vectors increase the coding gain as well as the performance of a complete video coder, but at the cost of an augmented complexity. © 2007 IEEE.
Cagnazzo, M.; Poggi, G.; Verdoliva, L.
Region-based transform coding of multispectral images Journal Article
In: IEEE TRANSACTIONS ON IMAGE PROCESSING, vol. 16, no. 12, pp. 2916–2926, 2007.
@article{ 11577_3469516,
title = {Region-based transform coding of multispectral images},
author = { M. Cagnazzo and G. Poggi and L. Verdoliva},
doi = {10.1109/TIP.2007.909315},
year = {2007},
date = {2007-01-01},
journal = {IEEE TRANSACTIONS ON IMAGE PROCESSING},
volume = {16},
number = {12},
pages = {2916--2926},
abstract = {We propose a new efficient region-based scheme for the compression of multispectral remote-sensing images. The region-based description of an image comprises a segmentation map, which singles out the relevant regions and provides their main features, followed by the detailed (possibly lossless) description of each region. The map conveys information on the image structure and could even be the only item of interest for the user; moreover, it enables the user to perform a selective download of the regions of interest, or can be used for high-level data mining and retrieval applications. This approach, with the multiple pieces of information required, may seem inherently inefficient. The goal of this research is to show that, by carefully selecting the appropriate segmentation and coding tools, region-based compression of multispectral images can be also effective in a rate-distortion sense, thus providing an image description that is both insightful and efficient. To this end, we define a generic coding scheme, based on Bayesian image segmentation and on transform coding, where several key design choices, however, are left open for optimization, from the type of transform, to the rate allocation procedure, and so on. Then, through an extensive experimental phase on real-world multispectral images, we gain insight on such key choices, and finally single out an efficient and robust coding scheme, with Bayesian segmentation, class-adaptive Karhunen-Loève spectral transform, and shape-adaptive wavelet spatial transform, which outperforms state-of-the-art and carefully tuned conventional techniques, such as JPEG-2000 multicomponent or SPIHT-based coders. © 2007 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We propose a new efficient region-based scheme for the compression of multispectral remote-sensing images. The region-based description of an image comprises a segmentation map, which singles out the relevant regions and provides their main features, followed by the detailed (possibly lossless) description of each region. The map conveys information on the image structure and could even be the only item of interest for the user; moreover, it enables the user to perform a selective download of the regions of interest, or can be used for high-level data mining and retrieval applications. This approach, with the multiple pieces of information required, may seem inherently inefficient. The goal of this research is to show that, by carefully selecting the appropriate segmentation and coding tools, region-based compression of multispectral images can be also effective in a rate-distortion sense, thus providing an image description that is both insightful and efficient. To this end, we define a generic coding scheme, based on Bayesian image segmentation and on transform coding, where several key design choices, however, are left open for optimization, from the type of transform, to the rate allocation procedure, and so on. Then, through an extensive experimental phase on real-world multispectral images, we gain insight on such key choices, and finally single out an efficient and robust coding scheme, with Bayesian segmentation, class-adaptive Karhunen-Loève spectral transform, and shape-adaptive wavelet spatial transform, which outperforms state-of-the-art and carefully tuned conventional techniques, such as JPEG-2000 multicomponent or SPIHT-based coders. © 2007 IEEE.
Andre, T.; Cagnazzo, M.; Antonini, M.; Barlaud, M.
JPEG2000-compatible scalable scheme for wavelet-based video coding Journal Article
In: EURASIP JOURNAL ON IMAGE AND VIDEO PROCESSING, vol. 2007, pp. 1–11, 2007.
@article{ 11577_3469527,
title = {JPEG2000-compatible scalable scheme for wavelet-based video coding},
author = { T. Andre and M. Cagnazzo and M. Antonini and M. Barlaud},
doi = {10.1155/2007/30852},
year = {2007},
date = {2007-01-01},
journal = {EURASIP JOURNAL ON IMAGE AND VIDEO PROCESSING},
volume = {2007},
pages = {1--11},
abstract = {We present a simple yet efficient scalable scheme for wavelet-based video coders, able to provide on-demand spatial, temporal, and SNR scalability, and fully compatible with the still-image coding standard JPEG2000. Whereas hybrid video coders must undergo significant changes in order to support scalability, our coder only requires a specific wavelet filter for temporal analysis, as well as an adapted bit allocation procedure based on models of rate-distortion curves. Our study shows that scalably encoded sequences have the same or almost the same quality than nonscalably encoded ones, without a significant increase in complexity. A full compatibility with Motion JPEG2000, which tends to be a serious candidate for the compression of high-definition video sequences, is ensured.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We present a simple yet efficient scalable scheme for wavelet-based video coders, able to provide on-demand spatial, temporal, and SNR scalability, and fully compatible with the still-image coding standard JPEG2000. Whereas hybrid video coders must undergo significant changes in order to support scalability, our coder only requires a specific wavelet filter for temporal analysis, as well as an adapted bit allocation procedure based on models of rate-distortion curves. Our study shows that scalably encoded sequences have the same or almost the same quality than nonscalably encoded ones, without a significant increase in complexity. A full compatibility with Motion JPEG2000, which tends to be a serious candidate for the compression of high-definition video sequences, is ensured.
2006
Cagnazzo, M.; Gaetano, R.; Parrilli, S.; Verdoliva, L.
Adaptive region-based compression of multispectral images Conference
Proceedings – International Conference on Image Processing, ICIP, 2006, ISBN: 1-4244-0480-0.
@conference{ 11577_3469806,
title = {Adaptive region-based compression of multispectral images},
author = { M. Cagnazzo and R. Gaetano and S. Parrilli and L. Verdoliva},
doi = {10.1109/ICIP.2006.312916},
isbn = {1-4244-0480-0},
year = {2006},
date = {2006-01-01},
booktitle = {Proceedings - International Conference on Image Processing, ICIP},
pages = {3249--3252},
abstract = {The region-based description of multispectral images enables important high-level tasks such as data mining and retrieval, and region-of-interest selection. In order to obtain an efficient representation of such images we resort to adaptive transform coding techniques. Such techniques, however, require a considerable information overhead, which must be carefully managed to obtain a satisfactory rate-distortion performance. In this work we develop several region-based coding schemes and compare them with conventional (non-adaptive) and class-based schemes, so as to single out the rate-distortion gains/losses of this approach. ©2006 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The region-based description of multispectral images enables important high-level tasks such as data mining and retrieval, and region-of-interest selection. In order to obtain an efficient representation of such images we resort to adaptive transform coding techniques. Such techniques, however, require a considerable information overhead, which must be carefully managed to obtain a satisfactory rate-distortion performance. In this work we develop several region-based coding schemes and compare them with conventional (non-adaptive) and class-based schemes, so as to single out the rate-distortion gains/losses of this approach. ©2006 IEEE.
Cagnazzo, M.; Gaetano, R.; Parrilli, S.; Verdoliva, L.
Region based compression of multispectral images by classified KLT Conference
European Signal Processing Conference, 2006.
@conference{ 11577_3469692,
title = {Region based compression of multispectral images by classified KLT},
author = { M. Cagnazzo and R. Gaetano and S. Parrilli and L. Verdoliva},
year = {2006},
date = {2006-01-01},
booktitle = {European Signal Processing Conference},
abstract = {A new region-based algorithm is proposed for the compression of multispectral images. The image is segmented in homogeneous regions, each of which is subject to spectral KLT, spatial shape-adaptive DWT, and SPIHT encoding. We propose to use a dedicated KLT for each region or for each class rather than a single global KLT. Experiments show that the classified KLT guarantees a significant increase in energy compaction, and hence, despite the need to transmit more side information, it provides a valuable performance gain over reference techniques.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
A new region-based algorithm is proposed for the compression of multispectral images. The image is segmented in homogeneous regions, each of which is subject to spectral KLT, spatial shape-adaptive DWT, and SPIHT encoding. We propose to use a dedicated KLT for each region or for each class rather than a single global KLT. Experiments show that the classified KLT guarantees a significant increase in energy compaction, and hence, despite the need to transmit more side information, it provides a valuable performance gain over reference techniques.
Cagnazzo, M.; Delfino, F.; Vollero, L.; Zinicola, A.
Trading off quality and complexity for a HVQ-based video codec on portable devices Journal Article
In: JOURNAL OF VISUAL COMMUNICATION AND IMAGE REPRESENTATION, vol. 17, no. 3, pp. 564–572, 2006.
@article{ 11577_3469529,
title = {Trading off quality and complexity for a HVQ-based video codec on portable devices},
author = { M. Cagnazzo and F. Delfino and L. Vollero and A. Zinicola},
doi = {10.1016/j.jvcir.2005.12.001},
year = {2006},
date = {2006-01-01},
journal = {JOURNAL OF VISUAL COMMUNICATION AND IMAGE REPRESENTATION},
volume = {17},
number = {3},
pages = {564--572},
abstract = {Bandwidth and processing requirements of multimedia applications typically exceed capabilities of portable terminals with current technology. Applications should hence be able to accommodate their requirements to run on these devices. In this paper, we provide a performance characterization of a video codec based on techniques such as hierarchical vector quantization which trade off complexity and reproduction quality. Comparison with standard codecs shows a remarkable reduction of coding times, such that real-time coding/decoding of video becomes possible even on low-power devices. This complexity reduction is counterbalanced by reproduction quality impairment. Nevertheless, for application such as video-conference, subjective quality seems to be fairly acceptable. Our analysis also quantifies some limitations of low-power devices with current technology. © 2005 Elsevier Inc. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Bandwidth and processing requirements of multimedia applications typically exceed capabilities of portable terminals with current technology. Applications should hence be able to accommodate their requirements to run on these devices. In this paper, we provide a performance characterization of a video codec based on techniques such as hierarchical vector quantization which trade off complexity and reproduction quality. Comparison with standard codecs shows a remarkable reduction of coding times, such that real-time coding/decoding of video becomes possible even on low-power devices. This complexity reduction is counterbalanced by reproduction quality impairment. Nevertheless, for application such as video-conference, subjective quality seems to be fairly acceptable. Our analysis also quantifies some limitations of low-power devices with current technology. © 2005 Elsevier Inc. All rights reserved.
Cagnazzo, M.; Cicala, L.; Poggi, G.; Verdoliva, L.
Low-complexity compression of multispectral images based on classified transform coding Journal Article
In: SIGNAL PROCESSING-IMAGE COMMUNICATION, vol. 21, no. 10, pp. 850–861, 2006.
@article{ 11577_3469528,
title = {Low-complexity compression of multispectral images based on classified transform coding},
author = { M. Cagnazzo and L. Cicala and G. Poggi and L. Verdoliva},
doi = {10.1016/j.image.2006.08.003},
year = {2006},
date = {2006-01-01},
journal = {SIGNAL PROCESSING-IMAGE COMMUNICATION},
volume = {21},
number = {10},
pages = {850--861},
abstract = {Compression of remote-sensing images can be necessary in various stages of the image life, and especially on-board a satellite before transmission to the ground station. Although on-board CPU power is quite limited, it is now possible to implement sophisticated real-time compression techniques, provided that complexity constraints are taken into account at design time. In this paper we consider the class-based multispectral image coder originally proposed in [Gelli and Poggi, Compression of multispectral images by spectral classification and transform coding, IEEE Trans. Image Process. (April 1999) 476-489 [5]] and modify it to allow its use in real time with limited hardware resources. Experiments carried out on several multispectral images show that the resulting unsupervised coder has a fully acceptable complexity, and a rate-distortion performance which is superior to that of the original supervised coder, and comparable to that of the best coders known in the literature. © 2006 Elsevier B.V. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Compression of remote-sensing images can be necessary in various stages of the image life, and especially on-board a satellite before transmission to the ground station. Although on-board CPU power is quite limited, it is now possible to implement sophisticated real-time compression techniques, provided that complexity constraints are taken into account at design time. In this paper we consider the class-based multispectral image coder originally proposed in [Gelli and Poggi, Compression of multispectral images by spectral classification and transform coding, IEEE Trans. Image Process. (April 1999) 476-489 [5]] and modify it to allow its use in real time with limited hardware resources. Experiments carried out on several multispectral images show that the resulting unsupervised coder has a fully acceptable complexity, and a rate-distortion performance which is superior to that of the original supervised coder, and comparable to that of the best coders known in the literature. © 2006 Elsevier B.V. All rights reserved.
2005
Cagnazzo, M.; Cicala, L.; Poggi, G.; Scarpa, G.; Verdoliva, L.
An unsupervised segmentation-based coder for multispectral images Conference
13th European Signal Processing Conference, EUSIPCO 2005, 2005.
@conference{ 11577_3469805,
title = {An unsupervised segmentation-based coder for multispectral images},
author = { M. Cagnazzo and L. Cicala and G. Poggi and G. Scarpa and L. Verdoliva},
year = {2005},
date = {2005-01-01},
booktitle = {13th European Signal Processing Conference, EUSIPCO 2005},
pages = {1724--1727},
abstract = {To fully exploit the capabilities of satellite-borne multi/hyperspectral sensors, some form of image compression is required. The Gelli-Poggi coder[1], based on segmentation and class-based transform coding, has a very competitive performance, but requires some a-priori knowledge which is not available on-board. In this paper we propose a new version of the Gelli-Poggi coder which is fully unsupervised, and therefore suited for use on-board a satellite, and presents a better performance than the original. Numerical experiments on test multispectral images validate the proposed technique.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
To fully exploit the capabilities of satellite-borne multi/hyperspectral sensors, some form of image compression is required. The Gelli-Poggi coder[1], based on segmentation and class-based transform coding, has a very competitive performance, but requires some a-priori knowledge which is not available on-board. In this paper we propose a new version of the Gelli-Poggi coder which is fully unsupervised, and therefore suited for use on-board a satellite, and presents a better performance than the original. Numerical experiments on test multispectral images validate the proposed technique.
Cagnazzo, M.; Poggi, G.; Verdoliva, L.
Costs and advantages of shape-adaptive wavelet transform for region-based image coding Conference
Proceedings – International Conference on Image Processing, ICIP, vol. 3, 2005, ISBN: 0-7803-9134-9.
@conference{ 11577_3469684,
title = {Costs and advantages of shape-adaptive wavelet transform for region-based image coding},
author = { M. Cagnazzo and G. Poggi and L. Verdoliva},
doi = {10.1109/ICIP.2005.1530362},
isbn = {0-7803-9134-9},
year = {2005},
date = {2005-01-01},
booktitle = {Proceedings - International Conference on Image Processing, ICIP},
volume = {3},
pages = {197--200},
abstract = {Region-based encoding techniques have been long investigated for the compression of still images and video sequences and have recently gained much popularity, as testified by the object-based nature of the MPEG-4 video coding standard. This work aims at analyzing costs and advantages of implementing such an approach by shape-adaptive wavelet transform and shape-adaptive SP1HT. The analysis of several performance measures in a number of experiments confirm the potential of wavelet-based region-based approach, and provide insight about what performance gains and losses can be expected in various operative conditions. © 2005 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Region-based encoding techniques have been long investigated for the compression of still images and video sequences and have recently gained much popularity, as testified by the object-based nature of the MPEG-4 video coding standard. This work aims at analyzing costs and advantages of implementing such an approach by shape-adaptive wavelet transform and shape-adaptive SP1HT. The analysis of several performance measures in a number of experiments confirm the potential of wavelet-based region-based approach, and provide insight about what performance gains and losses can be expected in various operative conditions. © 2005 IEEE.
Cagnazzo, M.; Poggi, G.; Verdoliva, L.
Proceedings – International Conference on Image Processing, ICIP, vol. 1, 2005, ISBN: 0-7803-9134-9.
@conference{ 11577_3469878,
title = {A comparison of flat and object-based transform coding techniques for the compression of multispectral images},
author = { M. Cagnazzo and G. Poggi and L. Verdoliva},
doi = {10.1109/ICIP.2005.1529836},
isbn = {0-7803-9134-9},
year = {2005},
date = {2005-01-01},
booktitle = {Proceedings - International Conference on Image Processing, ICIP},
volume = {1},
pages = {657--660},
abstract = {In this work we implement and compare several state-of-the-art transform coding schemes for the compression of multispectral images, in order to better understand which elements have a deeper impact on the overall performance, and which tools guarantee the best results. All schemes are based on Karhunen-Löeve transform and/or Wavelet Transform, in various combinations, and use SPIHT as the coding engine. Moreover, besides the ordinary techniques, their object-based counterparts are also examined, so as to study the viability of such approach [1] for these images. Whenever possible, an optimal rate allocation strategy is applied. The experiments, performed on images acquired by two different sensors, highlight the superiority of KLT as spectral transform; the rough equivalence between object-based and ordinary techniques in terms of rate-distortion performance; and the importance of the optimal allocation. © 2005 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
In this work we implement and compare several state-of-the-art transform coding schemes for the compression of multispectral images, in order to better understand which elements have a deeper impact on the overall performance, and which tools guarantee the best results. All schemes are based on Karhunen-Löeve transform and/or Wavelet Transform, in various combinations, and use SPIHT as the coding engine. Moreover, besides the ordinary techniques, their object-based counterparts are also examined, so as to study the viability of such approach [1] for these images. Whenever possible, an optimal rate allocation strategy is applied. The experiments, performed on images acquired by two different sensors, highlight the superiority of KLT as spectral transform; the rough equivalence between object-based and ordinary techniques in terms of rate-distortion performance; and the importance of the optimal allocation. © 2005 IEEE.
2004
Andre, T.; Cagnazzo, M.; Antonini, M.; Barlaud, M.; Bozinovic, N.; Konrad, J.
(N,0) motion-compensated lifting-based wavelet transform Conference
ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing – Proceedings, vol. 3, 2004.
@conference{ 11577_3469402,
title = {(N,0) motion-compensated lifting-based wavelet transform},
author = { T. Andre and M. Cagnazzo and M. Antonini and M. Barlaud and N. Bozinovic and J. Konrad},
year = {2004},
date = {2004-01-01},
booktitle = {ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings},
volume = {3},
pages = {121--124},
abstract = {Motion compensation has been widely used in both DCT- and wavelet-based video coders for years. The recent success of temporal wavelet transform based on motion-compensated lifting suggests that a high-performance, scalable wavelet video coder may soon outperform best DCT-based coders. As recently shown, however, the motion-compensated lifting does not implement exactly its transversal equivalent unless certain conditions on motion are satisfied. In this paper, we review those conditions, and we discuss their importance. We derive a new class of temporal transforms, the so-called 1-N transversal or (N,0) lifting transforms, that are particularly interesting if those conditions on motion are not satisfied. We compare experimentally the 1-3 and 5-3 motion-compensated wavelet transforms for the ubiquitous block-motion model used in all video compression standards. For this model, the 1-3 transform outperforms the 5-3 transform due to the need to transmit additional motion information in the later case. This interesting result, however, does not extend to motion models satisfying the transversal/lifting equivalence conditions.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Motion compensation has been widely used in both DCT- and wavelet-based video coders for years. The recent success of temporal wavelet transform based on motion-compensated lifting suggests that a high-performance, scalable wavelet video coder may soon outperform best DCT-based coders. As recently shown, however, the motion-compensated lifting does not implement exactly its transversal equivalent unless certain conditions on motion are satisfied. In this paper, we review those conditions, and we discuss their importance. We derive a new class of temporal transforms, the so-called 1-N transversal or (N,0) lifting transforms, that are particularly interesting if those conditions on motion are not satisfied. We compare experimentally the 1-3 and 5-3 motion-compensated wavelet transforms for the ubiquitous block-motion model used in all video compression standards. For this model, the 1-3 transform outperforms the 5-3 transform due to the need to transmit additional motion information in the later case. This interesting result, however, does not extend to motion models satisfying the transversal/lifting equivalence conditions.
Cagnazzo, M.; Andre, T.; Antonini, M.; Barlaud, M.
A model-based motion compensated video coder with JPEG2000 compatibility Conference
Proceedings – International Conference on Image Processing, ICIP, vol. 4, 2004, ISBN: 0-7803-8554-3.
@conference{ 11577_3469401,
title = {A model-based motion compensated video coder with JPEG2000 compatibility},
author = { M. Cagnazzo and T. Andre and M. Antonini and M. Barlaud},
doi = {10.1109/ICIP.2004.1421547},
isbn = {0-7803-8554-3},
year = {2004},
date = {2004-01-01},
booktitle = {Proceedings - International Conference on Image Processing, ICIP},
volume = {4},
pages = {2255--2258},
abstract = {We present a highly scalable wavelet-based video coder, featuring a scan-based motion-compensated temporal wavelet transform (WT) with lifting schemes which have been speci cally designed for video. Output bitstream is compatible with JPEG2000, as it is used to compress temporal subbands (SBs). Rate allocation among SBs is done by means of an optimal algorithm which requires SBs rate-distortion (RD) curves. We propose a model-based approach allowing us to compute these curves with a considerable reduction in complexity. The use of temporal WT and JPEG2000 guarantees high scalability. © 2004 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
We present a highly scalable wavelet-based video coder, featuring a scan-based motion-compensated temporal wavelet transform (WT) with lifting schemes which have been speci cally designed for video. Output bitstream is compatible with JPEG2000, as it is used to compress temporal subbands (SBs). Rate allocation among SBs is done by means of an optimal algorithm which requires SBs rate-distortion (RD) curves. We propose a model-based approach allowing us to compute these curves with a considerable reduction in complexity. The use of temporal WT and JPEG2000 guarantees high scalability. © 2004 IEEE.
Cagnazzo, M.; Poggi, G.; Verdoliva, L.; Zinicola, A.
Region-oriented compression of multispectral images by shape-adaptive wavelet transform and spiht Conference
Proceedings – International Conference on Image Processing, ICIP, vol. 4, 2004, ISBN: 0-7803-8554-3.
@conference{ 11577_3469399,
title = {Region-oriented compression of multispectral images by shape-adaptive wavelet transform and spiht},
author = { M. Cagnazzo and G. Poggi and L. Verdoliva and A. Zinicola},
doi = {10.1109/ICIP.2004.1421600},
isbn = {0-7803-8554-3},
year = {2004},
date = {2004-01-01},
booktitle = {Proceedings - International Conference on Image Processing, ICIP},
volume = {4},
pages = {2459--2462},
abstract = {We present a new technique for the compression of remote-sensing hyperspectral images based on wavelet transform and zerotree coding of coefficients. In order to improve encoding efficiency, the image is first segmented in a small number of regions with homogeneous texture. Then, a shape-adaptive wavelet transform is carried out on each region, and the resulting coefficients are finally encoded by a shape-adaptive version of SPIHT. Thanks to the segmentation map (sent as a side information) region boundaries are faithfully preserved, and selective encoding strategies can be easily implemented. In addition, by-now homogeneous region textures can be more efficiently encoded. © 2004 IEEE.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
We present a new technique for the compression of remote-sensing hyperspectral images based on wavelet transform and zerotree coding of coefficients. In order to improve encoding efficiency, the image is first segmented in a small number of regions with homogeneous texture. Then, a shape-adaptive wavelet transform is carried out on each region, and the resulting coefficients are finally encoded by a shape-adaptive version of SPIHT. Thanks to the segmentation map (sent as a side information) region boundaries are faithfully preserved, and selective encoding strategies can be easily implemented. In addition, by-now homogeneous region textures can be more efficiently encoded. © 2004 IEEE.
Cagnazzo, M.; Andre, T.; Antonini, M.; Barlaud, M.
A smoothly scalable and fully JPEG2000-compatible video coder Conference
2004 IEEE 6th Workshop on Multimedia Signal Processing, 2004.
@conference{ 11577_3469400,
title = {A smoothly scalable and fully JPEG2000-compatible video coder},
author = { M. Cagnazzo and T. Andre and M. Antonini and M. Barlaud},
year = {2004},
date = {2004-01-01},
booktitle = {2004 IEEE 6th Workshop on Multimedia Signal Processing},
pages = {91--94},
abstract = {In this paper we analyze the scalability properties of the JPEG2000-compatible video encoder presented in [1], and we improve its performances by presenting a new technique for an efficient Motion Vectors (MVs) encoding, producing a motion bitstream also compatible with JPEG2000. Our study shows that, thanks to our encoding strategy and to our peculiar temporal filters, scalably encoded sequences have the same or almost the same quality than non-scalably encoded ones: this is what we call smooth scalability. We also compared our encoder performances with the recent H.264 standard, showing comparable or sometimes better performances.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
In this paper we analyze the scalability properties of the JPEG2000-compatible video encoder presented in [1], and we improve its performances by presenting a new technique for an efficient Motion Vectors (MVs) encoding, producing a motion bitstream also compatible with JPEG2000. Our study shows that, thanks to our encoding strategy and to our peculiar temporal filters, scalably encoded sequences have the same or almost the same quality than non-scalably encoded ones: this is what we call smooth scalability. We also compared our encoder performances with the recent H.264 standard, showing comparable or sometimes better performances.
Cagnazzo, M.; Poggi, G.; Scarpa, G.; Verdoliva, L.
Compression of multitemporal remote sensing images through Bayesian segmentation Conference
International Geoscience and Remote Sensing Symposium (IGARSS), vol. 1, Institute of Electrical and Electronics Engineers Inc., 2004.
@conference{ 11577_3471464,
title = {Compression of multitemporal remote sensing images through Bayesian segmentation},
author = { M. Cagnazzo and G. Poggi and G. Scarpa and L. Verdoliva},
year = {2004},
date = {2004-01-01},
booktitle = {International Geoscience and Remote Sensing Symposium (IGARSS)},
volume = {1},
pages = {281--284},
publisher = {Institute of Electrical and Electronics Engineers Inc.},
abstract = {Multitemporal remote sensing images are useful tools for many applications in natural resource management. Compression of this kind of data is an issue of interest, yet, only a few paper address it specifically, while general-purpose compression algorithms are not well suited to the problem, as they do not exploit the strong correlation among images of a multitemporal set of data. Here we propose a coding architecture for multitemporal images, which takes advantage of segmentation in order to compress data. Segmentation subdivides images into homogeneous regions, which can be efficiently and independently encoded. Moreover this architecture provides the user with a great flexibility in transmitting and retrieving only data of interest.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Multitemporal remote sensing images are useful tools for many applications in natural resource management. Compression of this kind of data is an issue of interest, yet, only a few paper address it specifically, while general-purpose compression algorithms are not well suited to the problem, as they do not exploit the strong correlation among images of a multitemporal set of data. Here we propose a coding architecture for multitemporal images, which takes advantage of segmentation in order to compress data. Segmentation subdivides images into homogeneous regions, which can be efficiently and independently encoded. Moreover this architecture provides the user with a great flexibility in transmitting and retrieving only data of interest.
2003
Valentin, V.; Cagnazzo, M.; Antonini, M.; Barlaud, M.
Scalable context-based motion vector coding for video compression Conference
Picture Coding Symposium, 2003.
@conference{ 11577_3469396,
title = {Scalable context-based motion vector coding for video compression},
author = { V. Valentin and M. Cagnazzo and M. Antonini and M. Barlaud},
year = {2003},
date = {2003-01-01},
booktitle = {Picture Coding Symposium},
pages = {63--69},
abstract = {State of the art video compression algorithms use motion compensation. Using such method gives better results by increasing the temporal correlation between pixels from consecutive frames. Most of the effort in increasing the performance of existing algorithms concentrates on the improvement of motion vector uses and residual coding. In this paper we propose a motion vectors computation and coding scheme for video compression which combines constrained block matching and scalable coding based on a three-step search-like decomposition.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
State of the art video compression algorithms use motion compensation. Using such method gives better results by increasing the temporal correlation between pixels from consecutive frames. Most of the effort in increasing the performance of existing algorithms concentrates on the improvement of motion vector uses and residual coding. In this paper we propose a motion vectors computation and coding scheme for video compression which combines constrained block matching and scalable coding based on a three-step search-like decomposition.
Cagnazzo, M.; Valentin, V.; Antonini, M.; Barlaud, M.
Motion vector estimation and encoding for motion compensated DWT Conference
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), vol. 2849, Springer Verlag, 2003.
@conference{ 11577_3469395,
title = {Motion vector estimation and encoding for motion compensated DWT},
author = { M. Cagnazzo and V. Valentin and M. Antonini and M. Barlaud},
doi = {10.1007/978-3-540-39798-4_30},
year = {2003},
date = {2003-01-01},
booktitle = {Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)},
volume = {2849},
pages = {233--242},
publisher = {Springer Verlag},
abstract = {In this work, we propose a new technique for estimation and encoding of motion vectors, in order to achieve an efficient and scalable representation of motion information. The framework is Motion Compensated Three-Dimensional Wavelet Transform (MC3DWT) video coding. At low bit-rates an efficient estimation and encoding of motion information is especially critical, as the scarce coding resources have to be carefully shared between motion vectors and transform coefficients. The proposed technique, called Constrained Motion Estimation, outperforms the usual "unconstrained" one at low to medium rates, and is essentially equivalent to it at higher rates. Moreover, the proposed encoding technique for Motion Vectors, based on Wavelet Transform and context-based bit-plane coder, gives a scalable representation of them. © Springer-Verlag Berlin Heidelberg 2003.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
In this work, we propose a new technique for estimation and encoding of motion vectors, in order to achieve an efficient and scalable representation of motion information. The framework is Motion Compensated Three-Dimensional Wavelet Transform (MC3DWT) video coding. At low bit-rates an efficient estimation and encoding of motion information is especially critical, as the scarce coding resources have to be carefully shared between motion vectors and transform coefficients. The proposed technique, called Constrained Motion Estimation, outperforms the usual “unconstrained” one at low to medium rates, and is essentially equivalent to it at higher rates. Moreover, the proposed encoding technique for Motion Vectors, based on Wavelet Transform and context-based bit-plane coder, gives a scalable representation of them. © Springer-Verlag Berlin Heidelberg 2003.
2002
Cagnazzo, Marco; Caputo, Antonio; Poggi, Giovanni; Verdoliva, Luisa
Codifica video scalabile a bassa complessità Conference
Didamatica 2002, 2002.
@conference{ 11577_3469392,
title = {Codifica video scalabile a bassa complessità},
author = { Marco Cagnazzo and Antonio Caputo and Giovanni Poggi and Luisa Verdoliva},
year = {2002},
date = {2002-01-01},
booktitle = {Didamatica 2002},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Cagnazzo, M.; Poggi, G.; Verdoliva, L.
The advantage of segmentation in SAR image compression Conference
International Geoscience and Remote Sensing Symposium (IGARSS), vol. 6, 2002.
@conference{ 11577_3469393,
title = {The advantage of segmentation in SAR image compression},
author = { M. Cagnazzo and G. Poggi and L. Verdoliva},
year = {2002},
date = {2002-01-01},
booktitle = {International Geoscience and Remote Sensing Symposium (IGARSS)},
volume = {6},
pages = {3320--3322},
abstract = {SAR images are severely degraded by speckle, and filtering is therefore a common practice. Filtering is especially useful before compression, to avoid spending valuable resources to represent noise; unfortunately, it also degrades important image features, like region boundaries. To overcome this problem, one can resort to a segmentation-based compression scheme, which allows one to preserve region boundaries, carry out intense denoising, and improve overall performance. In this work we assess the potential of segmentation-based compression through controlled experiments on synthetic SAR images. Numerical results seem to confirm the validity of this approach.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
SAR images are severely degraded by speckle, and filtering is therefore a common practice. Filtering is especially useful before compression, to avoid spending valuable resources to represent noise; unfortunately, it also degrades important image features, like region boundaries. To overcome this problem, one can resort to a segmentation-based compression scheme, which allows one to preserve region boundaries, carry out intense denoising, and improve overall performance. In this work we assess the potential of segmentation-based compression through controlled experiments on synthetic SAR images. Numerical results seem to confirm the validity of this approach.
Cagnazzo, M.; Poggi, G.; Verdoliva, L.
Low-complexity scalable video coding through table lookup VQ and index coding Conference
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), vol. 2515, Springer Verlag, 2002.
@conference{ 11577_3469394,
title = {Low-complexity scalable video coding through table lookup VQ and index coding},
author = { M. Cagnazzo and G. Poggi and L. Verdoliva},
doi = {10.1007/3-540-36166-9_15},
year = {2002},
date = {2002-01-01},
booktitle = {Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)},
volume = {2515},
pages = {166--175},
publisher = {Springer Verlag},
abstract = {The Internet community is very heterogeneous in terms of access bandwidth and terminal capabilities, hence, there is much interest for low-computation, software-only, scalable video coders that guarantee universal access to video communication. Scalability allows users to achieve a fair quality of service in relation to their resources. Low complexity, on the other hand, is necessary in order to ensure that also users with low computing power can be served. In this work, we propose a multiplication-free video codec, whose complexity is much reduced with respect to standard coders at the price of a limited increase in memory requirements. To this end we resort to very simple coding tools such as table lookup vector quantization (VQ) and conditional replenishment.We start from the simple coder proposed in [1], which already guarantees high scalability and limited computational burden, and improve upon it by further reducing complexity, as well as the encoding rate, with no effect on the encoding quality. The main innovation is the use of ordered VQ codebooks, which allows the encoder to generate correlated indexes, unlike in conventional VQ. Index correlation, in turn, allows us to carry out conditional replenishment (the most time-consuming operation in the original coder) by working on indexes rather than on block of pixels, and to reduce drastically its complexity. In addition, we also take advantage of the correlation among indexes to compress them by means of a predictive scheme, which leads to a 15-20% rate reduction in the base layer, without significant increase in complexity. Thanks to these and other minor optimizations we have obtained improved performance and, more important, a 60-70% reduction of the encoding time (on a general purpose machine) with respect to [1].},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The Internet community is very heterogeneous in terms of access bandwidth and terminal capabilities, hence, there is much interest for low-computation, software-only, scalable video coders that guarantee universal access to video communication. Scalability allows users to achieve a fair quality of service in relation to their resources. Low complexity, on the other hand, is necessary in order to ensure that also users with low computing power can be served. In this work, we propose a multiplication-free video codec, whose complexity is much reduced with respect to standard coders at the price of a limited increase in memory requirements. To this end we resort to very simple coding tools such as table lookup vector quantization (VQ) and conditional replenishment.We start from the simple coder proposed in [1], which already guarantees high scalability and limited computational burden, and improve upon it by further reducing complexity, as well as the encoding rate, with no effect on the encoding quality. The main innovation is the use of ordered VQ codebooks, which allows the encoder to generate correlated indexes, unlike in conventional VQ. Index correlation, in turn, allows us to carry out conditional replenishment (the most time-consuming operation in the original coder) by working on indexes rather than on block of pixels, and to reduce drastically its complexity. In addition, we also take advantage of the correlation among indexes to compress them by means of a predictive scheme, which leads to a 15-20% rate reduction in the base layer, without significant increase in complexity. Thanks to these and other minor optimizations we have obtained improved performance and, more important, a 60-70% reduction of the encoding time (on a general purpose machine) with respect to [1].