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Error resiliency transcoding and decoding solutions using distributed video coding techniques

Tamer Shanableh, Tony May, Faisal Ishtiaq
2008 Signal processing. Image communication  
This paper proposes a number of video transcoding techniques for the purpose of adding error resiliency.  ...  The proposed solutions make use of distributed video coding technologies which were originally reported in the literature for distributing coding complexity between the encoder and the decoder.  ...  This is achieved through a number of transcoding techniques such as requantization, requantization with drift compensation, and dropping DCT coefficients.  ... 
doi:10.1016/j.image.2008.05.005 fatcat:2wg337rx2ja6fe2gm6ijsvzsou

Video transcoding: an overview of various techniques and research issues

I. Ahmad, Xiaohui Wei, Yu Sun, Ya-Qin Zhang
2005 IEEE transactions on multimedia  
Thus, a transcoding mechanism is required to make the content adaptive to the capabilities of diverse networks and client devices. A video transcoder can perform several additional functions.  ...  In addition, a video transcoder can change the coding parameters of the compressed video, adjust spatial and temporal resolution, and modify the video content and/or the coding standard used.  ...  From Fig. 5 (b), we can get (1) (2) (3) where In Fig. 6 , the open-loop transcoder starts with the de-quantization of the DCT coefficients using the original quantizer levels .  ... 
doi:10.1109/tmm.2005.854472 fatcat:peox57puyjeitlf3dklf2qkx2m

Foveation embedded DCT domain video transcoding

Shizhong Liu, Alan C. Bovik
2005 Journal of Visual Communication and Image Representation  
In addition, fast algorithms for video foveation filtering and DCT domain inverse motion compensation are developed, which significantly improve the efficiency of video transcoding.  ...  In this paper, foveation, a property of the HVS, is exploited in video transcoding.  ...  In [1] , a simple open-loop video transcoder was proposed, in which the incoming bit-rate is down-scaled by truncating the high frequency DCT coefficients or performing a requantization process.  ... 
doi:10.1016/j.jvcir.2005.04.001 fatcat:ucjjyjkndreblmtvubdo5ulygm

Performance Optimization For Multimedia Transmission In Wireless Home Networks

Paolo Bucciol, Gabriella Convertino, Juan Carlos De Martin, Diego Melpignano, Antonio Servetti, Andrea Vitali
2006 Zenodo  
Publication in the conference proceedings of EUSIPCO, Florence, Italy, 2006  ...  the DCT domain the coefficients to achieve a defined output rate. • Frame rate change: it allows reducing the incoming frame rate of a compressed stream by dropping B frames.  ...  In particular, the prediction error downsampling works by cropping the lower frequency 4x4 coefficients of each block of a macroblock, and fusing them together into a single new 8x8 DCT block. • An automatic  ... 
doi:10.5281/zenodo.52988 fatcat:lt7i5mguanbnfc4cff64udncn4

Efficient Hybrid DCT-Domain Algorithm for Video Spatial Downscaling

Nuno Roma, Leonel Sousa
2007 EURASIP Journal on Advances in Signal Processing  
This algorithm receives the encoded DCT coefficient blocks of the input video sequence and efficiently computes the DCT coefficients of the scaled video stream.  ...  In order to meet any system needs, an optional and possible combination of the presented algorithm with high-order AC frequency DCT coefficients discarding techniques is also proposed, providing a flexible  ...  By approximately using the same number of operations, the DCT decimation transcoder processes only K 2 = 9 DCT coefficients of each block, while the proposed transcoder may process K 2 = 25 coefficients  ... 
doi:10.1155/2007/57291 fatcat:zdbktuen5jb2vpf34ihlc5xwyy

Object-based transcoding for adaptable video content delivery

A. Vetro, Huifang Sun, Yao Wang
2001 IEEE transactions on circuits and systems for video technology (Print)  
One of the main contributions of this paper is to discuss the degrees of freedom within an object-based transcoder and demonstrate the flexibility that it has in adapting the content.  ...  This paper introduces a new framework for video content delivery that is based on the transcoding of multiple video objects.  ...  This architecture is shown in Fig. 4 and resembles an open-loop scheme, which is used in the simulations.  ... 
doi:10.1109/76.911163 fatcat:stac4tlx6ngldlqqganqxr5dce

Content-Aware Scalability-Type Selection for Rate Adaptation of Scalable Video

Emrah Akyol, A. Murat Tekalp, M. Reha Civanlar
2007 EURASIP Journal on Advances in Signal Processing  
Next, the weights of this objective function are determined for different content (shot) types and different bitrates using a training procedure with subjective evaluation.  ...  Soccer videos scaled from 600 kbps to 100 kbps by the proposed content-aware selection of scalability type have been found visually superior to those that are scaled using a single scalability option over  ...  All transform coefficients can then be encoded using an embedded entropy coder to obtain SNR scalability. Alternatively, SNR scalability can be achieved by requantization.  ... 
doi:10.1155/2007/10236 fatcat:hmjp3zxjvzho7j4pn6un7b3pbu

Quality-Temporal Transcoder Driven by the Jerkiness

G. Iacovoni, S. Morsa, R. Felice
2005 IEEE International Conference on Multimedia and Expo  
We propose a new video homogeneous transcoding architecture DCT-based which relies on both quality and temporal reduction techniques.  ...  The proposed transcoder can meet the constraints of a realtime communication and it has been extensively tested under different conditions.  ...  Open-loop schemes suffer from drift errors. To overcome this problem DCT residual coefficients must be recomputed.  ... 
doi:10.1109/icme.2005.1521705 dblp:conf/icmcs/IacovoniMF05 fatcat:jciqyuthezbrzfbee5ht3wvoee

Adaptive video delivery using semantics

Olivier Steiger
2005
(a) Open-loop, partial decoding to DCT coefficients, then re-quantization. (b) Closed-loop, drift compensation for requantized data.  ...  Two examples of simplified architecture are shown in Figure 3 .8. In the open-loop system shown in Figure 3 .8(a), the input video bitstream is first partially decoded to the DCT coefficient level.  ...  This could for instance be used to control the variance of the lowpass filter used to perform background simplification.  ... 
doi:10.5075/epfl-thesis-3236 fatcat:6az7cgb7vnhbfj4uljnlctlese

Link Adaptation for Wireless Video Communication Systems [article]

Husameldin Mukhtar
2017 arXiv   pre-print
Chase combining is used, and it actually vanishes completely for particular codes.  ...  A semi-analytical solution is developed to model the performance of delay-constrained HARQ systems.  ...  Examples of transcoding techniques are requantization and discarding high frequency DCT coefficients. A drawback of transcoding techniques is the drift problem.  ... 
arXiv:1706.02981v1 fatcat:iw4gzxvx6jf2hnoit7wbmlmelu

Experiencing audio/video quality : an investigation into the relationship between perceived video quality and involvement [article]

N Nele Van Den Ende, DG Don = Dominique Bouwhuis, WA Wijnand IJsselsteijn, LMJ Lydia Meesters
2015
In that case, the DCT coefficients of the I-frames and the residual coding of the P-and B-frames are requantized, which lowers the bitrate.  ...  High quantisation values result in a less precise representation of the DCT coefficients but also in higher compression of the frequency data.  ... 
doi:10.6100/ir811109 fatcat:73wqrtndn5elnb2izwgwlagd2e