Harmonic, Inc.

General Instrument Corporation

Vtel Corporation

Paul E Haskell

James E Kaye

Purvin Bibhas Pandit

Arthur C Manansala

DelRae H Gardner

Amanda L Chin

Andrew W Johnson

William L Helms

David Drizen

Damien Kessler

Sen-ching S Cheung

Dackary Busch

Roughly described, pictures are divided into multiple spatial sections to be encoded by multiple section encoders. To address discontinuities of compression decisions across section boundaries, the multiple section encoders encode overlapping regions in a picture.

Multi-slice/tile encoder with overlapping spatial sections

Systems, methods and computer program products for transcoding advanced video coding (AVC) bitstreams into multiview video coding (MVC) bitstreams are described. In some implementations, a MVC transcoder may be used to convert non-anchor pictures (e.g., at a specified temporal point) into anchor pictures by using only inter-view prediction. The MVC transcoder also may utilize inter-view reference pictures (in addition to temporal reference pictures) in the motion estimation/mode decision functions of the non-anchor pictures. The output of the MVC transcoder may be one or more MVC bitstreams each representing a different view of a same scene or image.

Advanced video coding to multiview video coding transcoder

A scalable video compression method and apparatus for encoding an input frame sequence having temporally sequential frames includes partitioning each of the frames of the input frame sequence into a top field and a bottom field to form a base layer sequence of fields and an enhancement layer sequence of fields. The base layer sequence and the enhancement layer sequence each comprise temporally alternating top and bottom fields of the partitioned frames of the input frame sequence. The base layer sequence and the enhancement layer sequence are encoded, wherein at least one field of the enhancement layer sequence is encoded in dependence upon at least one of the fields of the base layer sequence.

H.264/AVC based approach to scalable video compression

Methods and systems for video coding are provided. A method includes receiving a digital video stream. The digital video stream includes multiple sequential independent frames. The method further includes storing a first frame of the digital video stream. The method also includes encoding a second frame of the digital video stream using motion compensation with the stored first frame as a reference.

System and method for adaptive video compression motion compensation

Roughly described, an input unencoded video stream is first encoded according to a high quality compression standard such as 1080P@60 AVC. The high quality compressed video stream is then transcoded into a scalable format, such as 1080P@60 SVC. Developing the scalable video stream by transcoding offers significant benefits over developing it natively from the original uncompressed picture sequence.

AVC to SVC transcoder

A method and apparatus for bit rate allocation, or statistical multiplexing, in a multi-channel video data encoder. A pre-processor in each channel determines a bit rate need prior to compression and encoding. A control processes the bit rate need in each channel to arrive at an allocated bit rate for each channel. The video data is then compressed and encoded according to the allocated bit rate. The bit rate demand accounts for various characteristics of the current picture data in each channel, including spatial activity, temporal activity, image size, frame rate, scene change, brightness, flash, fade, and horizontal pixel resolution. The system also biases the bit rate allocation according to inter-frame distance, whether the average spatial activity level is below a lower threshold, whether the inter-frame distance is above an upper threshold or below a lower threshold, whether the quantization of previous frames is above an upper threshold, the length of the Group of Pictures (GOP), and a user-selectable priority factor. The system also allocates any surplus bit rate among the channels to avoid having unused bandwidth.

Pre-processing of bit rate allocation in a multi-channel video encoder

A statistical multiplexing apparatus and method for encoding and combining a diversity of video signal resolutions and formats. Higher resolution signals are reduced to lower resolution signals for simplifying the a priori statistics gathering process. Alternately, input video signals in multiple formats are converted to a single common format prior to their application to an a priori statistics gatherer. A storage device contains the a priori statistics which are indicative of the encoding complexity of the video signals from which the encoded video bit streams will be generated. The original video signals are applied to encoders which compress the signals in accordance with bit allocation decisions generated by a statistics computer. The statistics computer uses the a priori statistics from the storage device to generate bit allocation decisions. Subsequently, the statistics computer may use both the a priori statistics and the a posteriori statistics received from the encoders in allocating bits. The resulting compressed video bit streams are applied to a multiplexer and combined into a single multiplexed bit stream for transmission on a single channel.

Statistical multiplexed video encoding for diverse video formats

Apparatus and methods for multiplexing data received from a plurality of sources to a communication channel. Each of the sources is assigned to one of at least two scheduling layers based in part upon one or more bit rate characteristics of the sources.

Apparatus and methods of multiplexing data to a communication channel

A system for remultiplexing packets that are provided at variable rates in digital bitstreams using a delay buffer and rate estimation. A bitstream with specific packet types provided at different rates is extracted from a multiplex and combined with other fixed or variable rate bit streams in such a way that timing delivery constraints on the extracted variable rate bitstream are followed. The extracted bitstream is smoothed to reduce variations in the data rate. The smoothed bitstream is then processed in first and second parallel paths. In the first path, selected packets are discarded to obtain a retained data stream. The data rate of the retained data stream is estimated and provided to a control. In the second path, the smoothed bitstream is delayed according to at least the processing time of the rate estimator in the first path, then the selected packets are discarded to obtain a delayed, retained data stream. The retained data stream in the second path is then remultiplexed with other data streams at a rate near the estimated data rate. For example, the invention is suitable for use at a cable television headend which grooms and remultiplexes digital transport streams that comply with the MPEG-2 standard.

Remultiplexing variable rate bitstreams using a delay buffer and rate estimation

A postfiltering process for improving the appearance of a video image includes motion compensated temporal filtering and spatial adaptive filtering. For each target pixel being filtered, the temporal filtering uses multiple motion vectors and one or more pixel values for a prior frame to determine one of more reference values for the target filter. In one embodiment, a weighted average of multiple motion vectors for blocks near or containing the target pixel value provides a filter vector that points to a pixel value in the prior frame. This pixel value is a reference value for the target pixel value and is combined with the target pixel value in a filter operation. Alternatively, multiple motion vectors for blocks near or containing the target pixel value point to pixel values in the prior frame that are averaged to determine a reference value for the target pixel value. In each alternative, the weighting for the average is selected according to the position of the target pixel value. The spatial filtering determines a dynamic range of pixel values in a smaller block containing the target pixel value and a dynamic range of pixel values in a larger block containing the target pixel value. The two dynamic ranges suggest the image context of the target pixel, and an appropriate spatial filter for the target pixel is selected according to the suggested context.

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Saratoga, CA, United States of America

Paul E Haskell