J. M. Boyce and R. D. Gaglianello. Packet loss effects on MPEG video sent over the public Internet. In Proc. of ACM Multimedia, September 1998.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....effective at the highest loss rates (28.6 and 38 ) While such rates are not common, high loss rates do occur at times. Studies on packet loss over the public Internet, MBone, and wireless networks verify that packet loss rates vary over time and tend to be bursty in nature. As an example, in [37] MPEG compressed video was sent over the Internet, and average loss rates ranging from 3.0 to 13.5 were reported. In [38] it was reported that Internet links occasionally experience loss rates up to 47 (and 68 for acknowledgment packets) In [39] loss rates ranging from 5.15 to 16.98 were ....

J. M. Boyce and R. D. Gaglianello, "Packet loss effects on MPEG video sent over the public Internet," ACM Multimedia, pp. 181--190, 1998.

....can extrapolate the rest of the message. If the power level drops further then P frames can also be discarded with the B frames. I frames are discarded last. We used a simulated video stream which uses the ratio of I, P and B frames for two video rates of 1 Mbps and 384 Kbps as obtained from [41]. RSVP uses the source addresses and ports to classify flows. The various packets within a flow were identified by using different Type of Service (TOS) bits in the IP header for the various flows. The aim of the experiment was to see the effect of reduced number of packets on the power level at ....

J. M. Boyce and R. D. Gaglianello, "Packet Loss Effects on MPEG Video Sent Over the Public Internet." www.acm.org/sigmm/MM98/electronic proceeding/boyce/index.html#intro, 1998.

....with a possible error propagation through its frames imposes a great diflculty on sending MPEG video streams over lossy networks. Small packet loss rates may translate into much higher frame error rates. For example, a 3 packet loss percentage could translate into a 30 frame error probability [5]. This situation may seriously degrade the perceived quality by a user at the video reproduction. Moreover, network resources may be wasted with the transmission 3 of information that becomes useless to the receiver. Some portion of the received data may become useless to the decoder as ....

Boyce, J. M. and R. D. Gaglianello: 1998, 'Packet Loss Effects on MPEG Video Sent Over the Public Internet'. In: Proc. of the ACM Multimedia 98.

....this approach reduces compression gains and in many cases does not adequately handle packet losses that occur in bursts. Prior work has gathered experimental results that describe packet loss characteristics for MPEG video and suggest the need for better error recovery and concealment techniques [11]. Motivated by prior analysis, as well a general model we have developed to explain the effects of packet loss on MPEG video, we have developed a system that uses receiver driven selective reliability in conjunction with receiver postprocessing to efficiently recover from packet losses in ....

....reliability, whereby certain portions of an MPEG 4 bitstream can be transmitted reliably. Prior work has proposed protocols that use selective retransmission for recovering from bit errors [36] Others have gathered empirical data on the effect of transmitting MPEG video over the Internet [11]. In our work, we derive a general packet loss model that explains the quality degradation of MPEG 4 in the face of packet loss as seen on the Internet, validate our packet loss model with experiments, and show through analysis and experiments how our system provides performance benefits. This ....

J. Boyce and R. Gaglianello. Packet loss effects on MPEG video sent over the public internet. In ACM Multimedia, 1998.

....an effort to align slices within packet boundaries. The variable length encoding and difference encoding used by MPEG 1 is very effective in reducing the bitrate, but both techniques make assumptions about what has been previously received. If these assumptions are wrong (caused by packet loss) [8], artifacts will develop in the new frame. Other discrete cosine transform (DCT) based algorithms like H.261, have been successfully adapted for use in computer networks by using a technique sometimes called conditional replenishment [19] The idea is, that instead of encoding the differences ....

J. Boyce and R. Gaglianello. Packet loss effects on mpeg video sent over the public internet. ACM Multimedia, 1998.

....links [9] On the contrary, it is well accepted that telephony users find round trip delays larger than 300 ms more like a half duplex connection than a real time conversation. In addition, too large audio packet loss rates (over 10 ) may have a tremendous impact on speech recognition ( 15] [6]) These observations put in evidence the importance of the trade off between the stochastic end to end delay of the played out audio packets and the packet losses, especially when dealing with the problem of unpredictable jitter typical of environments providing a best effort service. Hence the ....

J. Boyce, R. Gaglianello, "Packet Loss Effects on MPEG Video Sent Over the Public Internet", ACM Multimedia 98, 181-190, Electronic Edition, 1998

....video traffic to a maximum of 128 Kb s 512 Kb s, in order to prevent network congestion. Timing requirements on the other hand can be more relaxed for video. It was shown that small variations in interarrival delay between frames do not affect the perceptual quality of the stream s presentation [13, 14, 15, 16]. The same happens with fairly small error rates, especially when they follow a uniformly random pattern. In this case, bit errors are spread throughout each frame and result in barely noticeable erroneous or missing spots that do not alter the perceptual value of the scene. However, if the error ....

Boyce JM, Gaglianello RD. Packet Loss Effects on MPEG Video Sent over the Public Internet. Proceedings of the ACM Multimedia 98; New York, USA, 1998; 181-190.

....by the current Internet is not well suited for the transmission of high quality video such as MPEG 2. The burstiness of data traffic combined with limited network resources produce congestion episodes during which packets are dropped leading to severe quality degradation. It has been observed in [1], that packet loss incurred in the transmission of MPEG video over the public Internet varies over a wide range, with the peak rate well above the average. It has also been observed that a mere 3 packet loss affects 30 of the frames (due to dependencies in the encoded video bit stream) To limit ....

Boyce, J. Gaglianello, R. "Packet Loss Effects on MPEG video sent over the Public Internet", Proceedings of ACM MultiMedia, 1998.

....loss propagation as a result of inter block inter frame correlation. If a media stream is not prepared by taking the possible packet loss into account, the effect can be more severe than expected. For example, 3 packet loss in the MPEG coded bit stream could translate into a 30 frame error rate [9]. Thus, media streaming should be adaptive in adjusting the transmission rate and in selecting proper error resilient features based on the network condition. For example, it may drop frames in a certain preferred order (i.e. in the B , P , I frame order) 11] Recent research about the ....

J. Boyce and R. Gaglianello, "Packet loss effects on MPEG video sent over the public Internet," in Proc. of ACM Multimedia , pp. 181-190, Sep. 1998.

....and the client to deliver the data at a rate that prevents the client application from starvation. If some small percentage of packets get corrupted or lost, the presentation can continue without loss of satisfaction from the user s point of view. Retransmissions can cause unacceptable latency [1]. Guaranteeing adequate bandwidth requires network resource reservation. This may be done in the form of a VBR connection in an ATM network, with statistical transmission guarantees. Cells may be lost due to transient overload. Such capacity losses (or congestion losses ) may invalidate the ....

....ATM network, with statistical transmission guarantees. Cells may be lost due to transient overload. Such capacity losses (or congestion losses ) may invalidate the client s assumption on the expected error or loss rate, and may interfere with the client s ability to provide continuous playback [1][11] We have selected instead to use CBR connections which can have bandwidth renegotiated, providing a small amount of overhead to the operation of the system. If the network bandwidth cannot be maintained throughout stream delivery, some change to the delivery parameters is necessary. ....

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Jill M. Boyce and Robert D. Gaglianello. Packet Loss Effects on MPEG Video Sent Over the Public Internet. In ACM Multimedia, Bristol, England, September 1998.

....or less [2] Besides bit errors, whole packets may be lost, e.g. due to congestion. This is the predominant cause of loss [27] Unfortunately, there exists no precise knowledge about error occurrence or error models in the Internet, and only a few measurements are reported in literature. In [10], 384 Kbps and 1 Mbps MPEG video is transmitted over the Internet with different packet sizes using UDP IP. The average packet loss rates vary between 3 and 13.5 with greater loss rates during periods of high network activity, and on average, 1.7 to 15.4 of the packets arrived out of order. ....

Boyce, J. M., Gaglianello, R. D.: "Packet Loss Effects on MPEG Video Sent Over the Public Internet ", Proceedings of the 6th ACM International Multimedia Conference (ACM MM'98), Bristol, UK, Septeber 1998, pp. 181-190

....the timeliness of the data is more important than its fidelity. If some small percentage of packets get corrupted or lost, the presentation can continue without loss of satisfaction from the user s point of view. Retransmissions can cause unacceptable latency in high bandwidth video streams [1]. Guaranteeing adequate bandwidth requires network resource reservation which may be done in the form of a VBR connection in an ATM network. A VBR connection only provides statistical guarantees. Cells may be lost due to 2 Interface Attribute Database I O BUS Interface Reader Network ....

....Organization of System transient overload, even though the network switch accepted the connection. Such capacity losses (or congestion losses ) may invalidate the client s assumption on the expected error or loss rate, and may interfere with the client s ability to provide continuous playback [1, 14]. We have selected instead to use CBR connections which can have their bandwidth renegotiated. Renegotiation is not a trivial operation, although it has been shown to be very efficient [6] thus providing a small amount of overhead to the operation of the system. On networks that do not provide ....

[Article contains additional citation context not shown here]

Jill M. Boyce and Robert D. Gaglianello. Packet Loss Effects on MPEG Video Sent Over the Public Internet. In ACM Multimedia, Bristol, England, September 1998.

.... virtual VCR functions via a separate channel to the server (4) In continuous media applications, the timeliness of data retrieval is more important than precise fidelity [4] and methods of transmission requiring retransmission of lost or corrupt data introduce unacceptable worst case latencies [5]. Bandwidth must be reserved at both the disk and the network to ensure that the appropriate amount of data is available at the client application when it wishes to present a particular unit of data. The process of determining if such a reservation is possible is referred to as admission control. ....

J. M. Boyce and R. D. Gaglianello, "Packet Loss Effects on MPEG Video Sent Over the Public Internet," in ACM Multimedia, (Bristol, England), Sept. 1998.

....an effort to align slices within packet boundaries. The variable length encoding and difference encoding used by MPEG 1 is very effective in reducing the bitrate, but both techniques make assumptions about what has been previously received. If these assumptions are wrong (caused by packet loss) [8], artifacts will develop in the new frame. Other discrete cosine transform (DCT) based algorithms like H.261, have been successfully adapted for use in computer networks by using a technique sometimes called conditional replenishment [21] The idea is, that instead of encoding the differences ....

J. Boyce and R. Gaglianello. Packet loss effects on mpeg video sent over the public internet. ACM Multimedia, 1998, 1998.

....laboratory. In all tests conducted at the three sites, data loss was small and tolerable. Unsurprisedly, with the server running in Orlando, Florida, the data loss was much higher than that with the server running in Germany. This confirms the experimental results on packet loss conducted in [1]. In all the tests, the jitter between the synchronized presentation of the two streams was always within tens of milliseconds, which is not detectable by human hearing. Due to the space limitation, we only present the results between Buffalo, New York and Darmstadt, Germany. Loss rates for the ....

J.M. Boyce and R.D. Gaglianello. Packet loss effects on mpeg video sent over the public internet. In The proceedings of ACMMULTIMEDIA'98, pages 181--190, Bristol, UK, September 1998.

....generated by the application is transmitted in fixed length packets over a lossy network like the Internet, using a protocol with no feedback. In the presence of network congestion, some of these packets may be lost. The packet loss rate experienced by the sessions have daily and hourly variations [7]. For short image transmission sessions, the situations of unknown packet loss rate, mismatched packet loss rate or slow variability of the packet loss rate can be conveniently modeled as a compound packet erasure channel. A compound packet erasure channel is a channel whose packet erasure rate ....

J. M. Boyce and R. D. Gaglianello, "Packet loss effects on MPEG video sent over the public internet," in Proceedings, ACM Conference on Multimedia (Multimedia-98), (Bristol,

....as well. In the worst case, we may loose a whole group of pictures (GOP) typically equivalent to half a second of video. For various MPEG streams, our experiments have shown that a random loss of 1 of network packets can translate into as high as 10 damaged video frames. Similarly, Boyce et al. [4] noticed that packet loss rates as low as 3 translated into frame error rates as high as 30 . 3 Related work There are several issues that must be dealt with when we adjust multimedia data so that they can be transmitted over a best effort network, and these issues have been addressed in ....

J.M. Boyce and R.D. Gaglianello. Packet loss effects on MPEG video sent over the public Internet. In Proceedings of ACM MULTIMEDIA '98, pages 181--190, Bristol, England, Sept 1998.

....of consecutively lost packets in low bandwidth ( 100 kbps) audio streams transmit ted over the public Internet and suggested the use of error control mechanisms such as Forward Error Correction (FEC) and Automatic Repeat Request (ARQ) to recover from these packet losses. Boyce and Gaglianello [4] studied the effects of packet loss on MPEG streams of 384 kbps and 1 Mbps. They found that seemingly innocent packet loss rates could cause much higher frame loss rates. They also observed access constraints on the public Internet. We look at application level measurements taken over a backbone ....

Boyce, J. M. & Gaglianello, R. D., Packet Loss Effects on MPEG Video Sent Over The Public Internet, ACM Multimedia, Bristol, UK, 1998, pp. 181-190.

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J. M. Boyce and R. D. Gaglianello. Packet loss effects on MPEG video sent over the public Internet. In Proc. of ACM Multimedia, September 1998.

No context found.

Boyce, J.M., Gaglianello, R.D. "Packet Loss Effects on MPEG Video Sent Over the Public Internet", Proc. ACM Multimedia'98, 1998.

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