A Survey of Application Layer Techniques for Adaptive Streaming Of Multimedia
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paper_title: Adaptive vector quantization of image sequences using generalized threshold replenishment

paper_content:

We describe a new adaptive vector quantization (AVQ) algorithm designed for the coding of nonstationary sources. This new algorithm, generalized threshold replenishment (GTR), differs from prior AVQ algorithms in that it features an explicit, online consideration of both rate and distortion. Rate-distortion cost criteria are used in the determination of nearest-neighbor codewords and as well as in the decision to update the codebook. Results presented indicate that, for the coding of an image sequence: (1) most AVQ algorithms achieve distortion much lower than that of nonadaptive VQ for the same rate (about 1.5 bits/pixel), and (2) the GTR algorithm achieves rate-distortion performance substantially superior to that of other AVQ algorithms for low-rate coding, being the only algorithm to achieve a rate below 1.0 bits/pixel.
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paper_title: A rate control mechanism for packet video in the Internet

paper_content:

Datagram networks such as the Internet do not provide guaranteed resources such as bandwidth or guaranteed performance measures such as maximum delay. One way to support packet video in these networks is to use feedback mechanisms that adapt the output rate of video coders based on the state of the network. The authors present one such mechanism. They describe the feedback information, and how it is used by the coder control algorithm. They also examine how the need to operate in a multicast environment impacts the design of the control mechanism. This mechanism has been implemented in the H.261 video coder of IVS. IVS is a videoconference system for the Internet developed at INRIA. Experiments indicate that the control mechanism is well suited to the Internet environment. In particular, it makes it possible to establish and maintain quality videoconferences even across congested connections in the Internet. Furthermore, it prevents video sources from swamping the resources of the Internet, which could lead to unacceptable service to all users of the network. >
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paper_title: SAVE: an algorithm for smoothed adaptive video over explicit rate networks

paper_content:

Supporting compressed video efficiently on networks is a challenge because of its burstiness. Although a large number of applications using compressed video are rate adaptive, it is also important to preserve quality as much as possible. We propose a smoothing and rate adaptation algorithm, called SAVE, that the compressed video source uses in conjunction with explicit rate based control in the network. SAVE smoothes the demand from the source to the network, thus helping achieve good multiplexing gains. SAVE maintains the quality of the video and ensures that the delay at the source buffer does not exceed a bound. We examine the effectiveness of SAVE across 28 different traces (entertainment and teleconferencing videos) using different compression algorithms.
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paper_title: A rate control mechanism for packet video in the Internet

paper_content:

Datagram networks such as the Internet do not provide guaranteed resources such as bandwidth or guaranteed performance measures such as maximum delay. One way to support packet video in these networks is to use feedback mechanisms that adapt the output rate of video coders based on the state of the network. The authors present one such mechanism. They describe the feedback information, and how it is used by the coder control algorithm. They also examine how the need to operate in a multicast environment impacts the design of the control mechanism. This mechanism has been implemented in the H.261 video coder of IVS. IVS is a videoconference system for the Internet developed at INRIA. Experiments indicate that the control mechanism is well suited to the Internet environment. In particular, it makes it possible to establish and maintain quality videoconferences even across congested connections in the Internet. Furthermore, it prevents video sources from swamping the resources of the Internet, which could lead to unacceptable service to all users of the network. >
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paper_title: Control mechanisms for packet audio in the Internet

paper_content:

The Internet provides a single class best effort service. From an application's point of view, this service amounts in practice to providing channels with time-varying characteristics such as delay and loss distributions. One way to support real time applications such as interactive audio given this service is to use control mechanisms that adapt the audio coding and decoding processes based on the characteristics of the channels, the goal being to maximize the quality of the audio delivered to the destinations. In this paper, we describe and analyze a set of such control mechanisms. They include a jitter control mechanism and a combined error and rate control mechanism. These mechanisms have been implemented and evaluated over the Internet and the MBone. Experiments indicate that they make it possible to establish and maintain reasonable quality audioconferences even across fairly congested connections.
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paper_title: Time Constrained Bandwidth Smoothing For Interactive Video-On-Demand Systems

paper_content:

The use of a client-side buffer in the delivery of compressed prerecorded video can be an effective tool for removing the burstiness required of the underlying server and network by smoothing the bandwidth requirements for continuous delivery. Given a fixed-size smoothing buffer, several bandwidth smoothing algorithms have been introduced in the literature that are provably optimal under certain constraints, typically requiring large buffer residency times to realize their optimal properties. The large buffer residency times, however, make VCR functions harder to support. In this paper, we introduce the notion of time constrained bandwidth smoothing. Specifically, we introduce two new algorithms that, in addition to the size of the client side buffer, use a time constraint as a parameter in the bandwidth smoothing plan creation, making the plans more amenable to supporting VCR interactivity. Our results show that the buffer residency times can be reduced, while still allowing the bandwidth allocation to be smoothed for continuous video delivery.
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paper_title: Supporting stored video: reducing rate variability and end-to-end resource requirements through optimal smoothing

paper_content:

VBR compressed video is known to exhibit significant, multiple-time-scale bit rate variability. In this paper, we consider the transmission of stored video from a server to a client across a high speed network, and explore how the client buffer space can be used most effectively toward reducing the variability of the transmitted bit rate.We present two basic results. First, we present an optimal smoothing algorithm for achieving the greatest possible reduction in rate variability when transmitting stored video to a client with given buffer size. We provide a formal proof of optimality, and demonstrate the performance of the algorithm on a set of long MPEG-1 encoded video traces. Second, we evaluate the impact of optimal smoothing on the network resources needed for video transport, under two network service models: Deterministic Guaranteed service [1, 9] and Renegotiated CBR (RCBR) service [8, 7]. Under both models, we find the impact of optimal smoothing to be dramatic.
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paper_title: Rate-constrained bandwidth smoothing for delivery of stored video

paper_content:

Bandwidth smoothing techniques for the delivery of compressed prerecorded video have been shown effective in removing the burstiness required for the continuous playback of stored video. Given a fixed client-side buffer, several bandwidth smoothing algorithms have been introduced that are provably optimal under certain constraints. These algorithms, however, may be too aggressive in the amount of data that they prefetch, making it more difficult to support VCR functions that are required for interactive video-on- demand systems. In this paper, we introduce a rate- constrained bandwidth smoothing algorithm for the delivery of stored video that, given a fixed maximum bandwidth rate minimizes both the smoothing buffer requirements as well as the buffer residency requirements. By minimizing the buffer residency times, the clients and servers can remain more tightly coupled making VCR functions easier to support. A comparison between the rate-constrained bandwidth smoothing algorithm and other bandwidth smoothing algorithms is presented using a compressed full-length movie.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
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paper_title: Critical Bandwidth Allocation for the Delivery of Compressed Video

paper_content:

The transportation of compressed video data without loss of picture quality requires the network to support large fluctuations in bandwidth requirements. These fluctuations can be smoothed, but straightforward approaches to smoothing can still suffer from excessive buffering requirements, poor buffer utilization and an excessive number of bandwidth changes. This paper introduces critical bandwidth allocation, which reduces the number of bandwidth changes to a very small number, and achieves the maximum effectiveness from clientside buffers. A comparison between critical bandwidth allocation algorithms and other smoothing algorithms is presented, the sensitivity of the algorithm to jitter is examined, and implications for the design of network services are discussed.
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paper_title: An optimal bandwidth allocation strategy for the delivery of compressed prerecorded video

paper_content:

The transportation of prerecorded, compressed video data without loss of picture quality requires the network and video servers to support large fluctuations in bandwidth requirements. Fully utilizing a client-side buffer for smoothing bandwidth requirements can limit the fluctuations in bandwidth required from the underlying network and the video-on-demand servers. This paper shows that, for a fixed-size buffer constraint, the critical bandwidth allocation technique results in plans for continuous playback of stored video that have (1) the minimum number of bandwidth increases, (2) the smallest peak bandwidth requirements, and (3) the largest minimum bandwidth requirements. In addition, this paper introduces an optimal bandwidth allocation algorithm which, in addition to the three critical bandwidth allocation properties, minimizes the total number of bandwidth changes necessary for continuous playback. A comparison between the optimal bandwidth allocation algorithm and other critical bandwidth-based algorithms using 17 full-length movie videos and 3 seminar videos is also presented.
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Title: A Survey of Application Layer Techniques for Adaptive Streaming Of Multimedia

Section 1: Introduction
Description 1: Provide an overview of the need for adaptive multimedia streaming and the current challenges in supporting multimedia applications over heterogeneous and variable network conditions.

Section 2: Compression Level Methods
Description 2: Discuss various video compression algorithms and their features which are useful for adaptation, including discrete cosine transformation (DCT), wavelet transforms, and proprietary methods.

Section 3: MPEG Compression Standard
Description 3: Describe the MPEG set of standards used for video compression, focusing on MPEG-2, including its encoding techniques, types of frames (I, P, B), and adaptability features.

Section 4: Wavelet Encoding
Description 4: Explore wavelet compression methods, their approaches for video encoding, and the scalability features they support.

Section 5: Proprietary Methods
Description 5: Cover commercial applications that use proprietary compression and adaptation methods, such as RealVideo and Intel's Indeo.

Section 6: Application Streaming
Description 6: Discuss adaptive streaming techniques at the application level, including layered encoding, adaptive error control, adaptive synchronization, and smoothing.

Section 7: Layered Encoding
Description 7: Explain the methodology and benefits of layered encoding for video streaming, including network feedback mechanisms.

Section 8: Receiver Driven Multicast
Description 8: Describe receiver-driven layered multicast (RLM) and its approach to adapting the transmission of layered video through network feedback.

Section 9: Rate Shaping
Description 9: Examine rate shaping techniques which adjust the traffic rate generated by the video encoder according to current network conditions using feedback mechanisms.

Section 10: Error Control
Description 10: Discuss methods to mitigate errors and packet loss, including Automatic Repeat Request (ARQ) and Forward Error Correction (FEC).

Section 11: Adaptive FEC for Internet Audio
Description 11: Analyze an adaptive FEC-based error control scheme for interactive audio in the Internet.

Section 12: Adaptive FEC for Internet Video
Description 12: Discuss an adaptive FEC-based error control scheme specifically designed for Internet video.

Section 13: Adaptive Synchronization
Description 13: Explain methods for adaptive synchronization to solve both intramedia and intermedia synchronization issues in multimedia applications.

Section 14: Smoothing
Description 14: Explore techniques for smoothing or shaping the video information transmitted to mitigate rate variations of multimedia applications.

Section 15: Smoothing Algorithms
Description 15: Discuss various algorithms for smoothing compressed video streams to ensure continuous and optimal playback at the client side.

Section 16: Online Smoothing
Description 16: Examine online smoothing algorithms for live video applications that reduce the resource variability using window-based approaches.

Section 17: Proactive Buffering
Description 17: Describe rate-constrained bandwidth smoothing techniques for stored video and how they proactively manage buffers and bandwidth.

Section 18: Bridging Bandwidth Smoothing and Adaptation Techniques
Description 18: Discuss how combining reactive and passive techniques can optimize video quality over best-effort networks by utilizing a priori information.

Section 19: Example Adaptive Applications
Description 19: Provide examples of commercial adaptive applications such as Real Network Solutions, highlighting the adaptive streaming techniques they employ.

Section 20: Operating System Support for Adaptive Multimedia
Description 20: Discuss operating system-level support necessary for adaptive multimedia streaming, such as integrated CPU and network-I/O QoS management and adaptive rate-controlled scheduling.

Section 21: Related Work
Description 21: Present a summary of related research efforts, focusing on techniques that support multimedia streaming and identifying potential for adaptation.

Section 22: Summary
Description 22: Summarize key points from the survey, emphasizing the importance of adaptive techniques at different layers and the potential benefits of low-level network feedback.