Abstract: Systems and methods of media servers for estimating the video quality of experience (QoE) of human viewers of video content or communications at video receivers. With these systems and methods, a media server can collect, within a plurality of predetermined time windows synchronized in time, operational parameters of ingress and egress networks over which such video content or communications can be transmitted, as well as coding parameters of a video decoder and a video encoder within the media server. Having collected the operational parameters of the ingress network and egress network and the coding parameters of the video decoder and video encoder, the media server can determine QoE scores associated with some or all the ingress network, the video decoder, the video encoder, and the egress network, and estimate a resulting video QoE for a human viewer at a video receiver as a predefined combination of the respective QoE scores.

Abstract: Improved systems and methods of performing multimedia communications over multimedia communications networks, in which video data senders can maintain high video quality of experience (QoE) levels with increased reliability despite changes in available bandwidths of video data receivers. In the disclosed systems and methods, video encoding parameters employed by the video data senders, including at least the video frame size and/or the video frame rate, can be dynamically adapted to the available bandwidths of the video data receivers, taking into account possible effects of spatial scaling and/or temporal scaling of video frames on the resulting video QoE.

Abstract: Improved systems and methods of performing multimedia communications over multimedia communications networks, in which video data senders can maintain high video quality of experience (QoE) levels with increased reliability despite changes in available bandwidths of video data receivers. In the disclosed systems and methods, video encoding parameters employed by the video data senders, including at least the video frame size and/or the video frame rate, can be dynamically adapted to the available bandwidths of the video data receivers, taking into account possible effects of spatial scaling and/or temporal scaling of video frames on the resulting video QoE.

Abstract: Systems and methods of performing intra-frame refresh in multimedia communications over lossy packet networks, in which a video receiver can provide packet loss feedback information to a video transmitter, and the video transmitter can respond to the feedback information, in a manner that makes efficient use of available bandwidth. By providing one or more PLI messages from the video receiver to the video transmitter based on criteria related to the detection of an eventual missing video packet and/or the determination that the quality of a current reference frame is bad, and by pausing the providing of GNACK messages from the video receiver to the video transmitter while the PLI messages are being provided to the video transmitter, the total number of video packets required for transmission/retransmission can be reduced, thereby limiting the impact of the transmitted/retransmitted video packets on the available bandwidth while enhancing the video QoE of system users.

Abstract: Systems and methods that employ an application-assisted approach to adaptive spatio-temporal error concealment in video decoders. The systems and methods employ a video receiver that can receive real-time video frames from a video transmitter over a wired and/or wireless network. The video receiver includes an end system configurable as an application for consuming the content of the real-time video frames. The end system application can determine whether each received real-time video frame is complete or incomplete, whether each received slice is complete or incomplete, and provide such information to the video decoder for use in avoiding errors while decoding the respective real-time video frames.

Abstract: Systems and methods of recording real-time video transactions between computerized user devices that make more efficient use of the systems' computing resources. Such systems and methods can record real-time video transactions between computerized user devices (e.g., customer client devices, customer service agent devices) by exploiting similarities between (1) video frame data generated by the respective computerized user devices, and (2) video frame data composed by the systems that record the real-time video transactions, without substantially degrading the video quality of the recorded real-time video transactions.

Abstract: Systems and methods of handling packet errors associated with multimedia data received at data receivers from data senders, in which packet error feedback information is provided by the data receivers to the data senders in one or more real-time transport control protocol (RTCP) feedback packets. The data receivers can calculate, determine, or otherwise obtain costs associated with providing specific forms of packet error feedback information in the RTCP feedback packets, and further calculate, determine, or otherwise obtain wait times for handling out-of-order packets, as well as receiving retransmissions of lost packets. By handling packet errors associated with multimedia data while taking into account such costs and wait times, each of which can have an impact on system bandwidth and/or latency, the systems and methods can more reliably achieve the quality of experience (QoE) generally desired and/or required for multimedia data transmissions.

Abstract: Systems and methods of media servers for estimating the video quality of experience (QoE) of human viewers of video content or communications at video receivers. With these systems and methods, a media server can collect, within a plurality of predetermined time windows synchronized in time, operational parameters of ingress and egress networks over which such video content or communications can be transmitted, as well as coding parameters of a video decoder and a video encoder within the media server. Having collected the operational parameters of the ingress network and egress network and the coding parameters of the video decoder and video encoder, the media server can determine QoE scores associated with some or all the ingress network, the video decoder, the video encoder, and the egress network, and estimate a resulting video QoE for a human viewer at a video receiver as a predefined combination of the respective QoE scores.

Abstract: Systems and methods of performing intra-frame refresh in multimedia communications over lossy packet networks, in which a video receiver can provide packet loss feedback information to a video transmitter, and the video transmitter can respond to the feedback information, in a manner that makes efficient use of available bandwidth. By providing one or more PLI messages from the video receiver to the video transmitter based on criteria related to the detection of an eventual missing video packet and/or the determination that the quality of a current reference frame is bad, and by pausing the providing of GNACK messages from the video receiver to the video transmitter while the PLI messages are being provided to the video transmitter, the total number of video packets required for transmission/retransmission can be reduced, thereby limiting the impact of the transmitted/retransmitted video packets on the available bandwidth while enhancing the video QoE of system users.

Abstract: Systems and methods of performing rate control in scalable video encoders that can be used to provide videoconferencing, announcements, and live video streaming to multiple participant devices having diverse bandwidths, resolutions, and/or other device characteristics. The systems and methods can accommodate different target bit rates of the multiple participant devices by operating on scalable video bitstreams in a multi-layer video format, including a base layer having one or more reference video frames, and an enhancement layer having one or more disposable non-reference, predictive video frames.

Abstract: Systems and methods of handling packet errors associated with multimedia data received at data receivers from data senders, in which packet error feedback information is provided by the data receivers to the data senders in one or more real-time transport control protocol (RTCP) feedback packets. The data receivers can calculate, determine, or otherwise obtain costs associated with providing specific forms of packet error feedback information in the RTCP feedback packets, and further calculate, determine, or otherwise obtain wait times for handling out-of-order packets, as well as receiving retransmissions of lost packets. By handling packet errors associated with multimedia data while taking into account such costs and wait times, each of which can have an impact on system bandwidth and/or latency, the systems and methods can more reliably achieve the quality of experience (QoE) generally desired and/or required for multimedia data transmissions.

Abstract: Systems and methods of dynamically adapting multimedia data transmit rates of data senders to available bandwidths of data receivers, in which the available bandwidths are estimated by the data senders using at least reception quality feedback information provided in real-time transport control protocol (RTCP) report packets. The data senders can obtain several bandwidth estimation parameters, such as a packet loss ratio and a round trip delay, from the reception quality feedback information, as well as multimedia data transmit rates from the data senders to the data receivers, and obtain estimates of the available bandwidths of the data receivers using at least the bandwidth estimation parameters and multimedia data transmit rates. Further, using the estimated available bandwidth, the data senders can dynamically adapt the multimedia data transmit rates to the available bandwidths for more reliably achieving the quality of experience (QoE) desired and/or required for multimedia data transmissions.

Abstract: Systems and methods of video conferencing, in which existing video encoders associated with a multipoint control unit (MCU) can be shared among conference participant devices, depending upon the availability of processor and/or memory resources for the MCU. In making decisions regarding the sharing of video encoders, the systems and methods take into account various parameters associated with potential conference participant devices and the total cost of the processor/memory resources for the MCU, to determine whether a video encoder of the MCU can be shared with, or allocated to, the respective conference participant devices. By determining whether to share or allocate a video encoder of the MCU, depending upon the available processor/memory resources for the MCU, the MCU can be made to operate with increased stability. The systems and methods can be applied to any application that sends the same content to multiple receivers, including announcement and video streaming applications.

Abstract: Systems and methods of performing rate control in scalable video encoders that can be used to provide videoconferencing, announcements, and live video streaming to multiple participant devices having diverse bandwidths, resolutions, and/or other device characteristics. The systems and methods can accommodate different target bit rates of the multiple participant devices by operating on scalable video bitstreams in a multi-layer video format, including a base layer having one or more reference video frames, and an enhancement layer having one or more disposable non-reference, predictive video frames.

Abstract: Improved systems and methods of video decoding and recording in real-time video communications for use in lossy network environments. The disclosed systems and methods can employ a plurality of wait time thresholds for retransmission of missing video packets, based at least on the processing performed on the respective video packets, such processing including video decoding in a real-time video communication between client devices, and video recording and storing in a video file. The disclosed system and methods can also adaptively perform error concealment on video frames in the bitstream domain prior to recording and storing encoded video frame data in a video file, based at least on estimates of the complexities of the respective video frames.

Abstract: Systems and methods of recording real-time video transactions between computerized user devices that make more efficient use of the systems' computing resources. Such systems and methods can record real-time video transactions between computerized user devices (e.g., customer client devices, customer service agent devices) by exploiting similarities between (1) video frame data generated by the respective computerized user devices, and (2) video frame data composed by the systems that record the real-time video transactions, without substantially degrading the video quality of the recorded real-time video transactions.

Abstract: Improved systems and methods of performing multimedia communications over multimedia communications networks, in which video data senders can maintain high video quality of experience (QoE) levels with increased reliability despite changes in available bandwidths of video data receivers. In the disclosed systems and methods, video encoding parameters employed by the video data senders, including at least the video frame size and/or the video frame rate, can be dynamically adapted to the available bandwidths of the video data receivers, taking into account possible effects of spatial scaling and/or temporal scaling of video frames on the resulting video QoE.

Abstract: Systems and methods of performing intra-frame refresh in multimedia communications over lossy packet networks, in which a video receiver can provide packet loss feedback information to a video transmitter, and the video transmitter can respond to the feedback information, in a manner that makes efficient use of available bandwidth. By providing one or more PLI messages from the video receiver to the video transmitter based on criteria related to the detection of an eventual missing video packet and/or the determination that the quality of a current reference frame is bad, and by pausing the providing of GNACK messages from the video receiver to the video transmitter while the PLI messages are being provided to the video transmitter, the total number of video packets required for transmission/retransmission can be reduced, thereby limiting the impact of the transmitted/retransmitted video packets on the available bandwidth while enhancing the video QoE of system users.

Abstract: Systems and methods of video conferencing, in which existing video encoders associated with a multipoint control unit (MCU) can be shared among conference participant devices, depending upon the availability of processor and/or memory resources for the MCU. In making decisions regarding the sharing of video encoders, the systems and methods take into account various parameters associated with potential conference participant devices and the total cost of the processor/memory resources for the MCU, to determine whether a video encoder of the MCU can be shared with, or allocated to, the respective conference participant devices. By determining whether to share or allocate a video encoder of the MCU, depending upon the available processor/memory resources for the MCU, the MCU can be made to operate with increased stability. The systems and methods can be applied to any application that sends the same content to multiple receivers, including announcement and video streaming applications.

Abstract: Systems and methods of video conferencing, in which existing video encoders associated with a multipoint control unit (MCU) can be shared among conference participant devices, depending upon the availability of processor and/or memory resources for the MCU. In making decisions regarding the sharing of video encoders, the systems and methods take into account various parameters associated with potential conference participant devices and the total cost of the processor/memory resources for the MCU, to determine whether a video encoder of the MCU can be shared with, or allocated to, the respective conference participant devices. By determining whether to share or allocate a video encoder of the MCU, depending upon the available processor/memory resources for the MCU, the MCU can be made to operate with increased stability. The systems and methods can be applied to any application that sends the same content to multiple receivers, including announcement and video streaming applications.