Cisco Technology, Inc.

Zhejiang University

Sijia Chen

Siping Tao

Rui Zhang

Wayne Liu

Hui Liu

Lu Yu

Paul G Bright-Thomas

Jing Wu

Huipin Zhang

Yi Guo

Jochen Christof Schirdewahn

Xing Jin

Yang Hu

Sawyer Shan

Volvet Zhang

Li Yao

Huade Shi

Dunbi Huang

Jianpeng Wang

Mayan Fei

Deqiang Ye

Zhou Qiang

Mengkang Wang

Kai Li

In various embodiments, a device receives a first video stream of a video conference. The device receives a second video stream of the video conference. The second video stream includes an indicated location for video of the second video stream relative to video of the first video stream. The device merges the first video stream and the second video stream into an overlapped video having the video of the second video stream located at the indicated location relative to the video of the first video stream. The device provides the overlapped video for display.

Transport mechanisms for video stream merging with overlapping video

In one embodiment, a system for setting frame priority according to priority levels includes a video encoder to encode a first video frame of a live video stream yielding an encoded first video frame having a first priority level, and a processor to read, from a memory, an estimate of a time delay, the time delay being a time for data in the live video stream to be transferred from a first device to a second device, and determine if the estimate of the time delay exceeds a pre-defined delay, and wherein if the estimate of the time delay exceeds the pre-defined delay, the video encoder is operative to encode a second video frame with a higher priority level than the first priority level, the second video frame being a most recent video frame to be presented from the live video stream for encoding after the first video frame. Related apparatus and methods are also described.

Frame priority system

In one embodiment, a managed cache system, includes a cache memory to receive storage units via an uplink from a transmitting client, each storage unit including a decodable video unit, each storage unit having a priority, and enable downloading of the storage units via a plurality of downlinks to receiving clients, and a controller processor to purge the cache memory of one of the storage units when all of the following conditions are satisfied: the one storage unit is not being downloaded to any of the receiving clients, the one storage unit is not currently subject to a purging exclusion, and another one of the storage units now residing in the cache, having a higher priority than the priority of the one storage unit, arrived in the cache after the one storage unit. Related apparatus and methods are also described.

Screen sharing cache management

A method, a device and computer readable storage media facilitate providing screen content including a plurality of video frames that are displayed by a computing device. During coding of the screen content, a suitable predictor is found that is used to code pixel blocks from one or more frames. The suitable predictor is found by selecting a pixel block of a current frame, conducting a direction based search by comparing pixel blocks within a search window of a reference frame with the selected pixel block of the current frame to determine whether a match exists, and, in response to a determination that no sufficient match has been found, conducting a feature oriented search by comparing pixel blocks of the reference frame with the selected pixel block of the current frame to find a suitable match based upon a common feature.

Utilizing a search scheme for screen content video coding

Techniques are provided for reference frame management for screen content video coding using hash or checksum functions. A video data stream including a plurality of frames is received, each frame including a plurality of pixels that define content within the frame. A plurality of hash code values associated with partitioned portions of a current frame are determined, where each hash code value is determined as an output value from a hash or checksum function based upon an input value comprising pixel values for a corresponding partition within the current frame. The current frame is compared with a plurality of reference frames based upon a comparison of the hash code values of the current frame with hash code values of the reference frames. A reference frame is selected as a candidate reference frame for coding the current frame.

Reference frame management for screen content video coding using hash or checksum functions

Techniques are provided to improve user experience at endpoint devices that are participating in a multipoint screen content sharing session. A server in a multipoint communication system receives video frames from a sending endpoint device in the communication session that involves one or more other endpoint devices that are to receive video frames from the sending endpoint device. The video frames include key reference frames that use either intra-frame prediction or inter-frame prediction based only on other key reference frames. The server stores the key reference frames. When a new receiving endpoint device joins the communication session, the server sends all the stored key reference frames to the new receiving endpoint device. All video frames received from the sending endpoint device are forwarded to existing ordinary receiving endpoint devices. Key reference frames and some, but not all, non-key reference video frames are forwarded to existing low-capacity receiving endpoint devices.

Efficient frame forwarding in large scale real-time screen content sharing meetings

In one embodiment, a perceptual video coder obtains local video content, and calculates a feature index for each of one or more features of a video unit of the local video content. Each feature index is then directly mapped to a delta quantization parameter (QP) using a linear fractional model that explicitly establishes a relation between the delta QP and a Human Visual System (HVS) insensitivity index, e.g., where the delta QP is set based on a comparison between a local strength of the HVS insensitivity index and an overall strength of a particular frame of the local video content. Accordingly, a QP of an adaptive quantization may be refined by adding to it each delta QP, such that adaptive quantization may be performed on the video unit based on the refined QP.

Adaptive quantization for perceptual video coding

A method and apparatus for second order prediction are provided. In the decoding method, the reconstruction of decoded picture comprises second order prediction and compensation and second prediction storage. The second order prediction and compensation comprises first prediction and compensation and second prediction and compensation, input of which includes reconstructed first order residue and second order residue. The encoding method comprises second order prediction and second prediction storage. Second order prediction consists of first prediction and second prediction, input of which includes reconstructed first order residue and second order residue, and it will generate bit-stream accordingly. This invention will eliminate redundancy using second order prediction encoding and decoding method, so that coding efficiency will be improved.

Method of second order prediction and video encoder and decoder using the same

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Hangzhou, China

Sijia Chen