Abstract: In one embodiment, bridges in a computer network maintain a per-port mapping table for each of its ports, where each mapping table maps, for each virtual connection (of more than 4K) at a respective port, i) frame encapsulation fields that uniquely identify a particular virtual connection at the respective port to ii) a particular multiple spanning tree (MST) instance. The bridges may then compute a checksum of a particular mapping table for a particular port, and share the checksum with a corresponding port interconnected with the particular port (e.g., of another bridge). Upon determining that the mapping tables at the corresponding ports match in response to the checksums matching, frames may then be forwarded between the ports based on the particular mapping table.

Abstract: In one embodiment, a bridge in a computer network may execute a spanning tree protocol (STP) for network topology and a registration protocol for traffic control of virtual connections (e.g., EVCs) at the bridge. For any gateway ports of the bridge inter-connected with a provider network, the bridge may generate “fake” received registration protocol join messages for a particular virtual connection at the gateway port. The bridge may then either i) propagate the join messages, in response to the gateway port being in a forwarding state according to the STP, on other forwarding ports of the bridge, or ii) in response to the gateway port not being in a forwarding state, block propagation of the join messages to other ports of the bridge.

Abstract: A router identifies in a data packet an address of a network device. An algorithm determines that the address and a first prefix in a tree data structure match up to a first mask length of the first prefix. The algorithm maintains the first prefix in a temporary storage location if there is a match, and determines whether the address and a second prefix in the tree data structure match up to a second mask length of the second prefix, wherein an external node of the second prefix is linked below an external node of the first prefix, and wherein the second mask length is longer than the first mask length. The algorithm maintains the second prefix as a better match of the address, if the address and the second prefix match up to the mask length of the second prefix.

Abstract: A highly reliable, carrier class passive optical network and associated devices which employs multiple instances of operating software in host systems, as well as mechanisms to automatically determine whether an individual OLT device has entered or left the system without disruption to overall system operation.

Abstract: A highly reliable, carrier class passive optical network and associated devices which employs multiple instances of operating software in host systems, as well as mechanisms to automatically determine whether an individual OLT device has entered or left the system without disruption to overall system operation.

Abstract: A system and method of processing a digital video signal for display on a display device, includes decoding an encoded digital video signal to produce a decoded digital video signal having a video source format; extracting coding information from the encoded digital video signal; executing a video quality improvement algorithm on the decoded digital video signal having the video source format using the extracted coding information, to produce a processed decoded digital video signal having the video source format; and converting the processed decoded digital video signal from the video source format to a video display format suitable for display on the display device. The system and method enhance the quality and/or reduce video artifacts in a video signal after it is decoded and prior to display on a display device.

Abstract: A method of improving luminance transition includes decoding a coded video bitstream around a transition from a first luminance level to a second luminance level; and providing luminance transition enhancement based on a metric indicative of video bitstream. Additionally, an apparatus that improves a luminance transition includes a video decoder and a module that determines a metric indicative of the degree of video coding artifacts in a signal. The apparatus also includes a video processing module that includes a luminance transient enhancement module. The luminance enhancement module provides transition based on at least a value of the metric at the transition.

Abstract: A method of determining processing a coded video signal includes decoding the coded video signal; determining a global indicator value for a frame from the decoded video; and providing video processing to the decoded video of the frame based on the global indicator. Additionally, an apparatus for processing coded digital video signals includes a coded video decoder; a metric calculation module; and a video processing module, wherein the metric calculation module calculates at least one value of a global indicator, which indicates the quality of the coded video signal, and where the metric calculation module provides the global indicator to the video processing module, which selectively addresses the coded video signal depending on the value.

Abstract: A method of reducing ringing artifacts in a compressed digital video signal includes decoding the coded video signal; determining plurality of metric values in a region near at least one pixel, wherein the metric values are greater than a particular value; and applying a deringing method to substantially reduce ringing artifacts near the pixel. An apparatus for selectively deringing a compressed digital video signal includes a decoding device, a metric calculation device and a metric-controlled deringing device, wherein the deringing device reduces ringing artifacts in certain regions of a video frame based on data from the metric calculation device. In accordance with another example embodiment, the metric-controlled deringing device updates the metric data of the frame based on the deringing.

Abstract: The present application develops a unified metric for digital video processing (UMDVP) to control video processing algorithms. The UMDVP metric is defined based on coding information of MPEG encoded video for each pixel in a frame. The definition of the UMDVP metric includes local spatial features. The UMDVP metric can be used to control enhancement algorithms to determine how much a pixel can be enhanced without boosting coding artifacts. It can also be used to instruct artifact reduction algorithms where and how much reduction operations are needed.

Abstract: A method and system for calculating a UME for each pixel in a frame of video data. A system for enhancing sharpness of a coded digital video signal representative a frame of block-based data is provided, comprising: a system for calculating a UME of each pixel in the frame in accordance with a frame type, wherein the calculating system includes: a mechanism that defines local spatial features in the frame; a mechanism that analyzes block-based motion estimation for the frame; a mechanism that detects a scene change in the frame; and a sharpness enhancer that improves sharpness to a decoded version of the digital video signal based on said UME.

Abstract: The present application is a new approach for jointly controlling resolution or sharpness enhancement and artifact reduction in order to improve picture quality for coded digital video. The present application provides a joint control that is based on a metric, the metric being used to determine which pixel and by how much it is to be enhanced and to determine on which pixel and to what degree to carry out the artifact reduction.

Abstract: The present invention is directed to method of detecting a scene change in video. The method includes a difference being calculated between consecutive frames of the video producing a plurality of difference values. A histogram is taken of the difference values. A scene change is detected if a majority of the difference values in the histogram exceed a predetermined value.

Abstract: The present invention is directed to method of detecting a scene change in video. The method includes a difference being calculated between consecutive frames of the video producing a plurality of difference values. A histogram is taken of the difference values. A scene change is detected if a majority of the difference values in the histogram exceed a predetermined value.

Abstract: A MPEG-2 decoder receives an MPEG-2 video stream containing discrete cosine transform (DCT) blocks and generates linear contrast enhanced DCT blocks applied to an inverse DCT processor contained therein. Preferably, the MPEG-2 decoder includes a linear contrast enhancement processor receiving the DCT blocks and generating the linear contrast enhanced DCT blocks, and the inverse DCT processor coupled to the linear contrast enhancement processor. Additionally, the MPEG-2 decoder can include a microprocessor which controls the linear contrast enhancement processor and the inverse DCT processor. A method and a memory containing computer readable instructions permitting the microprocessor to control the MPEG-2 decoder are also described.

Abstract: In accordance with the preferred embodiment of the present invention, a method of and system for improving temporal consistency of an enhanced signal representative of at least one frame using a sharpness enhancement algorithm with an enhancement gain are provided. The method comprises the steps of: receiving the enhanced signal comprising at least one frame, obtaining an enhancement gain for each pixel in the frame, retrieving an enhancement gain value of each pixel in a reference frame from a gain memory using motion vectors, identifying if the frame is an I, P or B frame type and determining an updated enhancement gain for an I frame type by calculating a gain map for use in the sharpness enhancement algorithm. The updated enhancement gain of each pixel is equal to enhancement gain previously determined for use in the sharpness enhancement algorithm.

Abstract: In accordance with the present invention a method of and a system for enhancing image quality of a coded digital video signal representative of at least one frame in a digital video system are provided. The method comprises the steps of creating a usefulness metric identifying a limit to sharpness enhancement to be applied to the coded digital video signal, defining local spatial features in the frame, and identifying a frame type for the frame. The usefulness metric created in the creating step is: UME = 1 - M * ( 1 + q_scale N ) 2 * q_scale num_bits max ? ( q_scale num_bits ) wherein UME is the usefulness metric, q_scale is a quantization scale for a macroblock, num_bits is a number of bits to encode a luminance block, max is a function representing a maximum value for the frame, and M and N are scaling factors.

Abstract: A method and system for calculating a UME for each pixel in a frame of video data. A system for enhancing sharpness of a coded digital video signal representative a frame of block-based data is provided, comprising: a system for calculating a UME of each pixel in the frame in accordance with a frame type, wherein the calculating system includes: a mechanism that defines local spatial features in the frame; a mechanism that analyzes block-based motion estimation for the frame; a mechanism that detects a scene change in the frame; and a sharpness enhancer that improves sharpness to a decoded version of the digital video signal based on said UME.

Abstract: The present invention is directed to method of detecting a scene change in video. The method includes a difference being calculated between consecutive frames of the video producing a plurality of difference values. A histogram is taken of the difference values. A scene change is detected if a majority of the difference values in the histogram exceed a predetermined value.

Abstract: In accordance with the present invention a method of and a system for enhancing image quality of a coded digital video signal representative of at least one frame in a digital video system are provided. The method comprises the steps of creating a usefulness metric identifying a limit to sharpness enhancement to be applied to the coded digital video signal, defining local spatial features in the frame, and identifying a frame type for the frame.