Packet loss visibility across SD, HD, 3D, and UHD video streams

The trend towards video streaming with increased spatial resolutions and dimensions, SD, HD, 3D, and 4kUHD, even for portable devices has important implications for displayed video quality. There is an interplay between packetization, packet loss visibility, choice of codec, and viewing conditions, which implies that prior studies at lower resolutions may not be as relevant. This paper presents two sets of experiments, the one at a Variable BitRate (VBR) and the other at a Constant BitRate (CBR), which highlight different aspects of the interpretation. The latter experiments also compare and contrast encoding with either an H.264 or an High Efficiency Video Coding (HEVC) codec, with all results recorded as objective Mean Opinion Score (MOS). The video quality assessments will be of interest to those considering: the bitrates and expected quality in error-prone environments; or, in fact, whether to use a reliable transport protocol to prevent all errors, at a cost in jitter and latency, rather than tolerate low levels of packet errors

IEEE 802.11ac wireless delivery of 4kUHD video: The impact of packet loss

This paper examines the 4kUHD video quality from streaming over an IEEE 802.11ac wireless channel, given measured levels of packet loss. Findings suggest that there is a strong content dependency to loss impact upon video quality but that, for short-range transmission, the quality is acceptable, making 4kUHD feasible on head-mounted displays

Simple packet scheduling method for data-partitioned video streaming over broadband wireless

Source-coded data partitioning of a compressed video stream protects more important data, reducing the risk of error corruption in wireless networks. However, because the data partitions of a video slice are each assigned to different network packets, in congestion-prone networks the increased number of packets per slice and their size disparity may increase the packet loss rate from buffer overflows. This paper recommends packet-size dependent scheduling as a relatively simple way of alleviating the problem, which problem remains real whenever there is an adverse distribution of packet sizes entering an access network. The paper also contributes an analysis of partition and packet sizes as a prelude to scheduling regimes

Prospects for live higher resolution video streaming to mobile devices: achievable quality across wireless links

From a review of the literature and a range of experiments, this paper demonstrates that live video streaming to mobile devices with pixel resolutions from Standard Definition up to 4k Ultra High Definition (UHD) is now becoming feasible by means of high-throughput IEEE 802.11ad at 60 GHz or 802.11ac at 5 GHz, and 4kUHD streaming is even possible with 802.11n operating at 5 GHz. The paper, by a customized implementation, also shows that real-time compression, assisted by Graphical Processing Units (GPUs) at 4kUHD, is also becoming feasible. The paper further considers the impact of packet loss on H.264/AVC and HEVC codec compressed video streams in terms of Structural Similarity (SSIM) index video quality. It additionally gives an indication of wireless network latencies and currently feasible frame rates. Findings suggest that, for medium-range transmission, the video quality may be acceptable at low packet loss rates. For hardware-accelerated 4kUHD encoding, standard frame rates may be possible but appropriate higher frame rates are only just being reached in hardware implementations. The target bitrate was found to be important in determining the display quality, which depends on the coding complexity of the video content. Higher compressed bitrates are recommended, as video quality may improve disproportionately as a result

Enabling WiMAX Video Streaming

IEEE 802.16 (WiMAX—Worldwide Interoperability for Microwave Access) (Andrews, 2007; Nuaymi, 2007) is a broadband wireless technology that allows rapid deployment of video streaming services, including Video-on-Demand (VoD), multicast varieties of IPTV (TV over the Internet Protocol) and broadcast, digital TV (Meloni. 2008). Streaming assumes limited buffering of data for video-rate display, rather than video file download, video messaging services, or hybrids for video clip download in which display is overlapped with download of video chunks

Packet loss visibility across SD, HD, 3D, and UHD video streams

The trend towards video streaming with increased spatial resolutions and dimensions, SD, HD, 3D, and 4kUHD, even for portable devices has important implications for displayed video quality. There is an interplay between packetization, packet loss visibility, choice of codec, and viewing conditions, which implies that prior studies at lower resolutions may not be as relevant. This paper presents two sets of experiments, the one at a Variable BitRate (VBR) and the other at a Constant BitRate(CBR), which highlight different aspects of the interpretation. The latter experiments also compare and contrast encoding with either an H.264 or an High Efficiency Video Coding (HEVC) codec, with all results recorded as objective Mean Opinion Score (MOS). The video quality assessments will be of interest to those considering: the bitrates and expected quality in error-prone environments; or, in fact, whether to use a reliable transport protocol to prevent all errors, at a cost in jitter and latency, rather than tolerate low levels of packet errors

IEEE 802.11ac wireless delivery of 4kUHD video: The impact of packet loss

This paper examines the 4kUHD video quality from streaming over an IEEE 802.11ac wireless channel, given measured levels of packet loss. Findings suggest that there is a strong content dependency to loss impact upon video quality but that, for short-range transmission, the quality is acceptable, making 4kUHD feasible on head-mounted displays

Broadband wireless video streaming: achieving unicast and multicast IPTV in a practical manner

This paper proposes a versatile IPTV video-streaming scheme that provides high-quality unicast with the aid of repair packets but still supports multicast without repair packets. Prior research on wireless multicast video streaming has addressed the risk of feedback implosion when providing adaptive Forward Error Correction (FEC). This approach has not been adopted by providers, who may either prefer unicast streaming or employ a sufficient level of application-layer FEC to avoid the need for adaptation. Instead in this paper, an adaptive, unicast rateless channel-coding scheme is also run in multicast mode. The paper demonstrates the method and the operating conditions for such a joint unicast/multicast service in terms of data rates and suitable video-content type. Data-partitioned source coding with gradual decoding refresh is adopted in the given scenarios, making for a practical broadband wireless streaming scheme

Unequal error protection for data partitioned H.264/AVC video broadcasting

Application Layer Forward Error Correction (AL-FEC) is becoming a popular addition to protocols for real-time video delivery over IP-based wireless networks. In particular, rateless codes are identified as suitable solution for AL-FEC due to their flexibility and capacity-approaching performance. Since each part of video data is not equally important for video reconstruction, it is beneficial to group it based on its importance, and then provide different degree of protection using Unequal Error Protection (UEP). Data partitioning (DP) is one such low-cost feature in H.264/AVC enabling partitioning of video data based on its importance. We propose schemes for the DP H.264/AVC video transmission using Raptor and Random Linear Codes (RLC) and investigate their performance as AL-FEC solutions in Digital Video Broadcasting. We provide comparisons between optimized Non-Overlapping Window RLC and Expanding Window (EW) RLC, which are two effective UEP RLC strategies. The results using realistic channel traces show viability of the EW RLC as a promising solution for multimedia broadcast applications