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differential coding OF PAL VIDEO SIGNALS USING INTRAFIELD PREDICTION

PROCEEDINGS OF THE INSTITUTION OF ELECTRICAL ENGINEERS-LONDON 1977年第12期124卷 1139-1147页

作者： DEVEREUX, VG Research Department British Broadcasting Corporation Tadworth UK

The paper discusses the application of differential pulse-code modulation (d.p.c.m.) and hybrid d.p.c.m./p.c.m. coding as a means of reducing the bit rate required for broadcast-quality System I (Pal, 625-line, 5.5 MHz) video signals. In the d.p.c.m. codes investigated, each codeword indicated the difference in magnitude between a sample of a video signal and a prediction of this sample based on samples already transmitted in the same and/or previous line periods with a sampling frequency equal to three times the colour subcarrier frequency. The codes examined required the transmission of between 3 and 6 bits per sample. Subjective test results are given for the picture impairment caused by quantising errors and transmission errors. The tests on quantising errors indicated that d.p.c.m. could provide a saving of nearly 2 bits per sample compared with p.c.m. A comparison of subjective test results and measurements of the r.m.s. quantising errors for d.p.c.m. and p.c.m. indicates that the picture impairment corresponding to a given signal/noise ratio is similar for both d.p.c.m. and p.c.m.

关键词： Signal processing and detection quantising errors picture impairment transmission errors colour television video signals PAL video signals differential coding pulse-code modulation PCM Radio and television transmitters intrafield prediction Codes encoding

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differential coding in networked controlled linear systems

Differential coding in networked controlled linear systems

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American Control Conference 2006

作者： Canudas-de-Wit, Carlos Rubio, Francisco R. Fornes, Jose Gomez-Estern, Fabio Ecole Natl Super Electrochim & Electrome Grenoble Inst Natl Polytech Grenoble CNRS UMR 5528Lab Automat Grenoble BP 46 F-38402 St Martin Dheres France Univ Seville Dept Automat Control & Syst Engn Seville Spain

ISBN: (纸本)1424402093

This paper investigates the closed-loop properties of the differential coding scheme known as Delta-Modulation (Delta-M) when used in feedback loops within the context of linear systems controlled through some communication network. We propose a new modified scheme of the original form of the Delta-M algorithm which improves the closed-loop properties. The new coding structure explicitly uses information from the system model. Stability properties for both: the continuous-time and the discrete-time version of this new algorithm are assessed. The results shows that the stability domain and the resulting precision of the Delta-M is limited by the position of the unstable poles of the system.

关键词： differential coding delta modulation stabilization of linear systems in Networked controlled systems

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differential coding in Polarizations with Half-Symbol-Period Timing Offset for Coherent PM-QPSK to Improve Phase-Noise Tolerance

Differential Coding in Polarizations with Half-Symbol-Period...

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21st International Optoelectronics and Communications Conference (OECC) / International Conference on Photonics in Switching (PS)

作者： Lu, Guo-Wei Sakamoto, Takahide Kamio, Yukiyoshi Natl Inst Informat & Commun Technol NICT 4-2-1 Nukui Kitamachi Koganei Tokyo 1848795 Japan Tokai Univ Inst Innovat Sci & Technol 4-1-1 Kitakaname Hiratsuka Kanagawa 2591292 Japan

We propose a phase-noise-tolerantc oherent PM-QPSK system with differential coding and half-symbol-period timing-offset in polarizations. Owing to the improved phase noise tolerance, error-free operation of lOGbaud PM... 详细信息

ISBN: (纸本)9784885523052

关键词： Coherent communications Phase modulation Phase noise differential coding

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A differential coding-Based Scheduling Framework for Wireless Multimedia Sensor Networks

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IEEE TRANSACTIONS ON MULTIMEDIA 2013年第3期15卷 684-697页

作者： Wang, Pu Dai, Rui Akyildiz, Ian F. Georgia Inst Technol Sch Elect & Comp Engn Broadband Wirless Networking Lab Atlanta GA 30332 USA N Dakota State Univ Dept Comp Sci Fargo ND 58105 USA

In wireless multimedia sensor networks (WMSNs), visual correlation exists among multiple nearby cameras, thus leading to considerable redundancy in the collected images. This paper proposes a differential coding-based scheduling framework for efficiently gathering visually correlated images. This framework consists of two components including MinMax Degree Hub Location (MDHL) and Maximum Lifetime Scheduling (MLS). The MDHL problem aims to find the optimal locations for the multimedia processing hubs, which operate on different channels for concurrently collecting images from adjacent cameras, such that the number of channels required for frequency reuse is minimized. After associating camera sensors with proper hubs, the MLS problem targets at designing a schedule for the cameras such that the network lifetime of the cameras is maximized by letting highly correlated cameras perform differential coding on the fly. It is proven in this paper that the MDHL problem is NP-complete, and the MLS problem is NP-hard. Consequently, approximation algorithms are proposed to provide bounded performance. Since the designed algorithms only take the camera settings as inputs, they are independent of specific multimedia applications. Experiments and simulations show that the proposed differential coding-based scheduling can effectively enhance the network throughput and the energy efficiency of camera sensors.

关键词： differential coding scheduling spatial correlation wireless multimedia sensor networks

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Efficient image compression scheme based on differential coding

Efficient image compression scheme based on differential cod...

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Symposium on Remote Sensing and GIS Data Processing and Applications;and Innovative Multispectral Technology and Applications

作者： Zhu, Li Wang, Guoyou Liu, Ying Huazhong Univ Sci & Technol Inst Pattern Recognit & Artificial Intelligence Lab Biometr & Med Image Proc State Key Lab Multispectral Informat Proc Technol Wuhan 430074 Hubei Peoples R China

ISBN: (纸本)9780819469540

Embedded zerotree (EZW) and Set Partitioning in Hierarchical Trees (SPIHT) coding, introduced by *** and Amir Said, are very effective and being used in many fields widely. In this study, brief explanation of the principles of SPIHT was first provided, and then, some improvement of SPIHT algorithm according to experiments was introduced. 1) For redundancy among the coefficients in the wavelet region, we propose differential method to reduce it during coding. 2) Meanwhile, based on characteristic of the coefficients' distribution in subband, we adjust sorting pass and optimize differential coding, in order to reduce the redundancy coding in each subband. 3) The image coding result, calculated by certain threshold, shows that through differential coding, the rate of compression get higher, and the quality of reconstructed image have been get raised greatly, when bpp(bit per pixel)=0.5, PSNR(Peak Signal to Noise Ratio) of reconstructed image exceeds that of standard SPIHT by 0.2 similar to 0.4db.

关键词： image compression Set Partitioning in Hierarchical Trees (SPIHT) differential coding

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Deep differential coding for High-Resolution Remote Sensing Scene Classification 2018

Deep Differential Coding for High-Resolution Remote Sensing ...

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International Conference on Image and Graphics Processing ICIGP)

作者： Shi, Qiuping Li, Jie Jiao, Zhicheng Wang, Ying Xidian Univ Sch Elect Engn 2 South Taibai Rd Xian Shaanxi Peoples R China

ISBN: (纸本)9781450363679

Scene classification is one of critical tasks in the interpretation of high-resolution remote sensing (HRRS) imagery. Most of the existing methods focus on learning efficient feature representations. Recently, deep convolutional neural network (CNN) shows its effectiveness in extracting feature of images, which is widely used in remote sensing. In this paper, we propose a novel feature representation method which called deep differential coding (DDC) for remote sensing scene classification. Firstly, we get convolutional feature maps from image using the pre-trained CNN model. Then, the dense features are encoded through our proposed differential coding (DC). Finally, features are obtained by max-pooling and sum-pooling. We extract features from the whole remote sensing image and object region of every image by our proposed DDC and the final global feature is the combination of two kinds of features. We have performed extensive experiments on two public datasets and the results demonstrate that our proposed method has an excellent performance compared with state-of-the-art methods.

关键词： Scene classification Remote Sensing CNN differential coding Dictionary

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Double-differential coding for orthogonal space-time block codes

Double-differential coding for orthogonal space-time block c...

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33rd IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Bhatnagar, Manav R. Hjorungnes, Are Song, Lingyang Univ Oslo UniK Univ Grad Ctr NO-2027 Kjeller Norway

ISBN: (纸本)9781424414833

Communications over multiple-input multiple-output (MIMO) channels with carrier offsets is an important practical and theoretical problem. Double-differential coding is a technique, which allows the receiver to decode the data without any channel or carrier offset knowledge. We propose a double-differential (DD) coding scheme which is applicable to any square orthogonal space-time block codes (OSTBC) using M-PSK constellation. The main advantages of the proposed DD coding scheme are: 1) The previously proposed DD codes are applicable only to the specific class of space-time block codes which follow the diagonal unitary group property, whereas our DD coding is applicable to any square OSTBC. 2) We propose a suboptimal decoder which preserves the linear decoding property of the OSTBC. We derive an upper bound of the pairwise error probability (PEP) of the proposed double-differential orthogonal space-time block codes (DDOSTBCs). The proposed DDOSTBC is able to achieve better performance than the similar rate existing DD coding scheme. In addition, the proposed DDOSTBC outperforms the conventional training based system.

关键词： double-differential modulation orthogonal space-time block codes MIMO system carrier offset differential coding

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Interpixel Interference Mitigation Using differential coding in Vehicular Visible Light Communication Based Image Sensor 32

Interpixel Interference Mitigation Using Differential Coding...

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32nd International Conference on Information Networking (ICOIN)

作者： Vuong, Dat Lee, Jaejin Hong, Sun K. Shin, Won-Yong Yoo, Myungsik Soongsil Univ Sch Elect Engn Seoul South Korea Dankook Univ Dept Comp Sci & Engn Gyeonggi Do South Korea

ISBN: (纸本)9781538622902

This paper proposes the differential coding in visible light communication using image sensor. The transmitted frame is a result of comparing the current bitstream with previous bitstreams. The purpose of this scheme is limiting the number of white LED in one frame to mitigate the interpixel interference (IPI). The image sensor is used to take snap consecutive image frames. The simulation outcome shows that proposed scheme gains the BER performance.

关键词： VLC differential coding BER LED image sensor

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Performance Analysis of differential coding for Hybrid PIM-CDMA Optical Wireless Communication Systems

Performance Analysis of Differential Coding for Hybrid PIM-C...

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9th IEEE Malaysia International Conference on Communications

作者： Kamakura, Koji Chiba Inst Technol Dept Comp Sci Chiba 2750016 Japan

ISBN: (纸本)9781424455324

The use of differential coding is proposed in hybrid pulse interval modulation-optical code division multiple access (hPIM-OCDMA) for optical wireless communication systems. In hPIM-OCDMA, although the 2(m)-ary symbol modulates the interval between pulses, the interval is vulnerable to multiple access interference (MAI), which can cause false-alarm pulses, resulting in consecutive errors in symbol detection. The differential coding improves the tolerance to MAI and enhances the channel coding against MAI. We analyze the bit error rate (BER) of hPIM-OCDMA with differential coding, considering that the dominant interference is due to the self-interference and MAI, which are caused by autocorrelation and cross-correlation constraints of strict optical orthogonal code (SOOC), respectively. Numerical results show that the use of the differential coding together with Reed-Solomon (RS) code offers better BER and high information rate, compared to the case without differential coding.

关键词： Pulse interval modulation (PIM) OCDMA hybrid PIM-OCDMA differential coding MAI

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An Algorithm for Simple differential Speech coding Based on Backward Adaptation Technique

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INFORMATICA 2018年第3期29卷 539-553页

作者： Tomic, Stefan S. Peric, Zoran H. Nikolic, Jelena R. Univ Nis Fac Elect Engn Aleksandra Medvedeva 14 Nish Serbia

This paper presents a simple differential speech signal coding algorithm, based on backward adaptation. The considered algorithm is executed in frame by frame manner, by implementing predictive and adaptive quantization techniques. Both prediction and adaptation are performed backward, based on the previously quantized input signal frame. This enables us to obtain high quality output signal, without increasing the bit rate. This research puts emphasis on the quantizer design, with the optimal support limit determination, and theoretical performance evaluation. Objective quality of the output signal is evaluated through signal to quantization noise ratio (SQNR). We perform theoretical and experimental analysis of the algorithm performance and provide comparative results of implementing speech signal coding techniques with similar complexity. Experimental results show that our simple differential speech coding algorithm satisfies the G. 712 Recommendation for high-quality speech coding at the bit rate of 6 bits per sample. This indicates that the algorithm can be successfully implemented in high quality speech signal coding.

关键词： speech coding algorithm backward adaptive technique prediction coding differential coding

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