Yazar "Tekalp A.M." seçeneğine göre listele
Listeleniyor 1 - 9 / 9
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Adaptive inter-view rate allocation for scalable stereo video coding with an objective stereo video quality measure [Ölçeklenebilir stereo video kodlama için objektif bir stereo video kalite ölçüsü ile bakişlararasi uyarlamali hiz tahsisi](2007) Özbek N.; Tekalp A.M.; Tunali E.T.[No abstract available]Öğe Adaptive streaming of scalable stereoscopic video over DCCP [Ölçeklenebilir stereo videolarin DCCP üzerinden uyarlamali akişlandirilmasi](2007) Özbek N.; Görkemli B.; Tekalp A.M.; Tunali E.T.We propose a new adaptive streaming model that utilizes DCCP in order to efficiently stream multi-view video over the Internet for 3DTV transport. The model effectively allocates the available channel bandwidth, which is calculated by DCCP, among the views. The video rate is adapted to the DCCP rate for each group of pictures (GoP) by adaptive extraction of layers from a scalable multi-view bitstream. The objective of the streaming model is to maximize perceived quality of the received 3D video while minimizing the number of possible display interrupts. Experimental results successfully demonstrate stereo video streaming over DCCP on wide area network.Öğe Bandwidth-aware multiple multicast tree formation for P2P scalable video streaming using hierarchical clusters(IEEE Computer Society, 2009) Fesci-Sayit M.; Tunali E.T.; Tekalp A.M.Peer-to-peer (P2P) video streaming is a promising method for multimedia distribution over the Internet, yet many problems remain to be solved such as providing the best quality of service to each peer in proportion to its available resources, low-delay, and fault tolerance. In this paper, we propose a new bandwidth-aware multiple multicast tree formation procedure built on top of a hierarchical cluster based P2P overlay architecture for scalable video (SVC) streaming. The tree formation procedure considers number of sources, SVC layer rates available at each source, as well as delay and available bandwidth over links in an attempt to maximize the quality of received video at each peer. Simulations are performed on NS2 with 500 nodes to demonstrate that the overall performance of the system in terms of average received video quality of all peers is significantly better if peers with higher available bandwidth are placed higher up in the trees and peers with lower bandwidth are near the leaves. ©2009 IEEE.Öğe Fast H.264/AVC video encoding with multiple frame references(2005) Ozbetf N.; Tekalp A.M.We focus on the question of how we can select the best multiple reference pictures for enhanced H.264 video encoding by a fast, computationally efficient method. We propose a simple histogram-similarity based method for selecting the best set of multiple reference pictures. Out-of-order coding of these frames is implemented by means of pyramid encoding. Experimental results show that the proposed approach can provide encoding time saving up to 23% with similar picture quality and bitrate for selected video sequences. © 2005 IEEE.Öğe Fast H.264/AVC video encoding with multiple frame references [Çoklu referans çerçevelerle hizli H.264/AVC video kodlama](2005) Özbek N.; Tekalp A.M.Enhanced reference picture selection in H.264 enables increasing coding efficiency at the expense of increasing complexity, in other words encoding time. We focus on the question how we can estimate the best multiple reference pictures by a fast, computationally efficient method. We propose a simple histogram similarity-based method for the selection of the best reference pictures. Out-of-order coding of these frames is implemented thanks to pyramid encoding and keeping them in the buffer is achieved by means of MMCO (Memory Management Control Operation) commands and long-term reference pictures. Experimental results show that the proposed approach can provide encoding time saving up to 20% with the similar picture quality and bitrate for the selected video sequence. © 2005 IEEE.Öğe Fast multi-frame reference video encoding with key frames(2005) Ozbek N.; Tekalp A.M.Enhanced reference picture selection in H.264 enables increasing compression efficiency at the expense of increasing complexity, in other words encoding time. We search how we can select the best multiple reference pictures by a fast, computationally efficient method. We propose a simple histogram-similarity based method for selecting the best set of multiple reference pictures. Out-of-order coding of these frames is implemented by means of pyramid encoding. Experimental results show that the proposed approach can provide encoding time saving up to 22% with similar picture quality and bitrate for selected video sequences.Öğe H.264 encoding of videos with large number of shot transitions using long-term reference pictures(2006) Ozbek N.; Tekalp A.M.Long-term reference prediction is an important feature of the H.264/AVC standard, which provides a trade-off between gain and complexity. A simple long-term reference selection method is presented for videos with frequent shot/view transitions in order to optimize compression efficiency at the shot boundaries. Experimental results show up to 50% reduction in the number of bits, at the same PSNR, for frames at the border of transitions.Öğe H.264 long-term reference selection for videos with frequent camera transitions [H.264 kodlamada sik kamera degişimli videolar i·çin uzun-dönem referans seçimi](2006) Özbek N.; Tekalp A.M.Long-term reference prediction is an important feature of the H.264/MPEG-4 AVC standard, which provides a tradeoff between compression gain and computational complexity. In this study, we propose a long-term reference selection method for videos with frequent camera transitions to optimize compression efficiency at shot boundaries without increasing the computational complexity. Experimental results show up to 50% reduction in the number of bits (at the same PSNR) for frames at the border of camera transitions. © 2006 IEEE.Öğe Unequal inter-view rate allocation using scalable stereo video coding and an objective stereo video quality measure(2008) Ozbek N.; Tekalp A.M.In stereoscopic 3D video, it is well-known that humans can perceive high quality 3D video provided that one of the views is in high quality. Hence, in stereo video encoding, the best overall rate vs. perceived-distortion performance may be achieved by reduction of the spatial, temporal, and/or quantization resolution of the second view, while keeping the first view in full resolution. In this paper, we address the best selection of unequal inter-view rate allocation strategy depending on the content of the video for a scalable multi-view video codec (SMVC)[1]. Since the perceived 3D video quality does not correlate well with the average PSNR of the two views, we propose a new quantitative measure using a weighted combination of two PSNR values and a jerkiness measure. We verified that unequal rate allocation between the left and right views results in better perceived stereo video quality. © 2008 IEEE.
