526 results about "MPEG-2" patented technology

Disclosed is a system for allowing on-demand delivery of data, such as MPEG-2 compressed video data, to a subscriber from a content server. The system utilizes a managed IP network that is coupled to the one or more content servers that allows the content servers to deliver data such as video, audio, and textual data with a guaranteed quality of service that is at least as good as broadcast quality service. The managed IP network is connected to a head end or other local cable service provider where video is delivered locally to subscribers. The IP transport data is translated to MPEG transport data, multiplexed onto an MPEG transport system, digitally modulated onto an rf carrier and up-converted to a specific frequency channel. The signal is then applied to the cable for delivery to the subscriber. Upstream signaling occurs through a set top box or computer that is connected to the cable and subsequently to a digital modulator/demodulator and ISP to a managed IP network 66. Low band signals can also be transmitted from the content servers back to the set top box or computer indicating confirmation of an order. Also, control signals such as stop, rewind, fast-forward, and slow can be transmitted back to the content server to control the transmission of data from the content server to the subscriber.

A system and method for displaying still video images related to video content in an interactive broadcast television system. The system and method of the present invention may also be used for simulating an Internet home page on an interactive television system. The present invention thus supports hyperlinked web-like navigational capabilities in an interactive television system. According to the method of the present invention, the video delivery system provides or broadcasts one or more audio/video channels each comprising video content and also provides or broadcasts at least one still image channel comprising a plurality of still video images, preferably MPEG-2 compressed still images. The user or viewer can select options displayed on the television screen to view desired information. When the set top box receives user input selecting an option to view one of the linked still images, the set top box captures the requested image from the still image broadcast channel, stores the image in memory, and displays the captured still video image corresponding to the selection. The still image being displayed may have associated interactive program content for displaying further selections, wherein these selections may be for viewing other images or content, for ordering information, or purchasing products. The user can thus selectively navigate between the video content and stills in a web-like hyperlinked fashion. In one embodiment, when a user is navigating through still images, the television program or video content which was being viewed is displayed in a small window overlaid on the still image being displayed. Also, when the set top box captures a requested image from the still image broadcast channel, the set top box preferably also pre-caches or pre-loads other related still images based on the probabilty that these related images will be subsequently requested by the user. The invention also includes an embodiment which provides user requested still images "on demand" on a dedicated "search" channel.

A system and method for generating trick play video streams, such as fast forward and fast reverse video streams, from an MPEG compressed normal play bitstream. The system receives a compressed normal play bitstream and filters the bitstream by extracting and saving only portions of the bitstream. The system preferably extracts I-frames and sequence headers, including all weighting matrices, from the MPEG bitstream and stores this information in a new file. The system then assembles or collates the filtered data into the proper order to generate a single assembled bitstream. The system also ensures that the weighting matrixes properly correspond to the respective I-frames. This produces a bitstream comprised of a plurality of sequence headers and I-frames. This assembled bitstream is MPEG-2 decoded to produce a new video sequence which comprises only one out of every X pictures of the original, uncompressed normal play bitstream. This output picture stream is then re-encoded with respective MPEG parameters desired for the trickplay stream, thus producing a trickplay stream that is a valid MPEG encoded stream, but which includes only one of every X frames. The present invention thus generates compressed trick play video streams which require reduced storage and reduced data transfer bandwidth requirements.

To reduce bandwidth of non-scalable MPEG-2 coded video, certain non-zero AC DCT coefficients for the 8x8 blocks are removed from the MPEG-2 coded video. In one implementation, high-frequency AC DCT coefficients are removed at the end of the coefficient scan order. This method requires the least computation and is most desirable if the reduced-bandwidth video is to be spatially sub-sampled. In another implementation, the smallest-magnitude AC DCT coefficients are removed. This method may produce an undesirable increase in the frequency of occurrence of escape sequences in the (run, level) coding. This frequency can be reduced by retaining certain non-zero AC DCT coefficients that are not the largest magnitude coefficients, and by increasing a quantization scale to reduce the coefficient levels. The reduced-bandwidth video can be used for a variety of applications, such as browsing for search and play-list generation, bit stream scaling for splicing, and bit-rate adjustment for services with limited resources and for multiplexing of transport streams.

Transform coefficients for blocks of pixels in an original picture are quantized to produce respective sets of quantization indices for the blocks of pixels. The quantization indices for at least some of the blocks are produced by using a quantization step size that is not uniform within each block. Largest magnitude quantization indices are selected from the respective sets of quantization indices for (run, level) encoding to produce the (run, level) encoded picture. For example, MPEG-2 coded video includes a set of non-zero AC discrete cosine transform (DCT) coefficients for 8x8 blocks of pixels. For scaling the MPEG-2 coded video, non-zero AC DCT coefficients are removed from the MPEG-2 coded video to produce reduced-quality MPEG-2 coded video that includes no more than a selected number of largest magnitude quantization indices for the non-zero AC DCT coefficients for each 8x8 block.

Original-quality MPEG coded video is processed to produce reduced-quality MPEG coded video for trick mode operation by removing non-zero AC DCT coefficients from the 8×8 blocks of I-frames of the MPEG coded video to produce I-frames of reduced-quality MPEG coded video, and inserting freeze frames in the reduced-quality MPEG coded video. Preferably, the coded video is stored in a main file, a fast-forward file and a fast-reverse file. The fast forward file and the fast reverse files contain reduced-quality I frames corresponding to original-quality I frames in the main file. A reading of the main file produces an MPEG transport stream for an audio-visual presentation at a normal rate, a reading of the fast-forward file produces an MPEG transport stream of the audio-visual presentation in a forward direction at a fast rate, and a reading of the fast-reverse file produces an MPEG transport stream of the audio-visual presentation in a reverse direction at a fast rate. Preferably, the files share a volume that includes at least one GOP index associating the corresponding I frames of the files.

A system and method for displaying still video images related to video content in an interactive broadcast television system. The system and method of the present invention may also be used for simulating an Internet home page on an interactive television system. The present invention thus supports hyperlinked web-like navigational capabilities in an interactive television system. According to the method of the present invention, the video delivery system provides or broadcasts one or more audio/video channels each comprising video content and also provides or broadcasts at least one still image channel comprising a plurality of still video images, preferably MPEG-2 compressed still images. The user or viewer can select options displayed on the television screen to view desired information. When the set top box receives user input selecting an option to view one of the linked still images, the set top box captures the requested image from the still image broadcast channel, stores the image in memory, and displays the captured still video image corresponding to the selection. The user can also request to view an image which is not currently being transmitted by the video delivery system. In this instance, the system provides user requested still images “on demand” on a dedicated “search” channel. The user can thus selectively navigate between the video content and stills in a web-like hyperlinked fashion.

A method, protocol and apparatus for transporting Advanced Video Coding (AVC) content, e.g., using MPEG-2 systems is disclosed. Specifically, the present method is related to the carriage of various flavors of AVC streams in a uniform fashion over MPEG-2 systems (e.g., both transport and program streams). AVC coding mandates only the VCL (video coding layer) elements and all other elements such as parameter sets, timing data and display parameters are optional in the in-band AVC stream. As all of these elements are required by MPEG-2 systems and for conformance verification of AVC streams, the present invention discloses MPEG-2 system specific tools and/or constraints to generate the optional elements that are not present in the in-band AVC stream.

A system and method for a seamless splicing/spot insertion strategy for MPEG-2 digital video/audio transport stream with no previously encoded information. This strategy, considering the time dependency between MPEG-2 frames, results in a new stream with smooth transition from a main stream to a spot stream without any encoded mark increasing possibilities for utilization of MPEG-2 contents. This strategy further facilitates local and remote switching (like local advertisement insertion) and produces successful decoding and presentation of all MPEG-2 packets around the splicing point. It takes into account several kinds of MPEG-2 related discontinuities: transport header continuity counter gaps, temporal reference discontinuity for frame presentation and PCR/PTS/DTS discontinuities.

An apparatus and method for inserting and extracting value added data in a TS (Transport Stream)-based MPEG-2 system is provided to improve the efficiency of the TS-based MPEG-2 system. A transport packet of a transport stream for transmission is checked to determine if it includes a stuffing byte field, on the basis of a header of the transport packet. If the transport packet includes a stuffing byte field, the value added data is inserted into the stuffing byte field, and the resulting transport packet is outputted. On the other hand, a transport packet of a received transport stream is checked to determine if it includes a stuffing byte field, on the basis of a header of the transport packet. If the transport packet includes a stuffing byte field, the value added data inserted in the stuffing byte field is extracted from the transport packet.

The systems disclosed here provide a complete standards-based end-to-end scalable system for storage, delivery and in-home distribution of digital content over IP networks using standard protocols such as Real-time Transport Protocol (“RTP”) or IP-encapsulated MPEG-2 Transport Stream, or traditional MPEG-2 networks. Mechanisms are provided for receiving content from one security domain, re-encrypting that content uniquely for a receiving device, persistently storing that content, and playing back that content at a later time to and within another security domain. The systems also provide the ability to stream the persistently-stored content from the initial receiving device to another device that has been authenticated as part of a, e.g., home network. This allows a media server, e.g., a dual-tuner set-top box (“STB”) with hard drive, to deliver recorded content to any TV in the house by streaming to media clients such as STBs.

This invention relates to methods of feature extraction from MPEG-2 and MPEG-4 compressed video sequences. The spatio-temporal compression complexity of video sequences is evaluated for feature extraction by inspecting the compressed bitstream and the complexity is used as a descriptor of the spatio-temporal characteristics of the video sequence. The spatio-temporal compression complexity measure is used as a matching criterion and can also be used for absolute indexing. Feature extraction can be accomplished in conjunction with scene change detection techniques and the combination has reasonable accuracy and the advantage of high simplicity since it is based on entropy decoding of signals in compressed form and does not require computationally expensive inverse Discrete Cosine Transformation (DCT).

An escape-code complexing method based on H.264 multi-path video includes applying fast conversion means of MPEG-2 to H.264 code and utilizing H.264 macro-block mode to select relativity to MPEG-2 motion compensation residual error as well as utilizing motion compensation residual error and MB mode as well as mapped H.264 macro-block mode obtained by MPEG-2 decoding to synthesize TS stream and to input multi-path MPEG-2 program stream to escape code complex server by SI interface through PCI bus and outputting escape-coded and complexed single H.264 video stream through PCI bus in ASI interface mode.

A disparity prediction stage and a motion prediction stage predict a disparity vector and a motion vector by extending a MPEG-2 structure into a view axis and using spatial/temporal correlation. A disparity/motion compensation stage compensates an image reconstructed by the disparity prediction stage and the motion prediction stage by using a sub-pixel compensation method. A residual image encoding stage performs an encoding to provide a better visual quality and a three-dimensional effect of an original image and the reconstructed image. A bit rate control stage controls a bit rate for assigning an effective amount of bit to each frame on the reconstructed image according to a bit rate. An entropy encoding stage generates a bit stream on multi-view video source data according to the bit rate.

A digital broadcasting transmission and/or reception system having an improved reception performance and a signal-processing method thereof. A digital broadcasting transmitter comprises a TRS encoder for to TRS-encode an MPEG-2 transmission stream having null data for inserting an SRS data and a TRS parity at predetermined positions, randomizer to input and randomize data stream from the TRS encoder, a SRS exchanger to replace the null data for inserting the SRS data to the known data, and an encoder for encoding a data streams to which the Known data is inserted. Accordingly, the present invention detects the known data from a signal received from a reception side and uses the detected known data for synchronization and equalization and further uses the TRS parity for correcting error of the received signal, so that the digital broadcasting reception performance can be improved at poor multipath channels.

A system and method for switching data packet traffic distribution across diverse transmission medium according to detected quality of service characteristics for a given data packet rate from server to client. It should be recognized that diverse medium are not interdependent with regard to fading or signal strength considerations. One mode of switching comprises switching all the data packets from transmission on a first medium to transmission over a second diverse medium. In a second mode of switching the distribution is changed according to a media-time coding mechanism in which typically data is being transmitted simultaneously across more than one of the multiple diverse medium. The data packet transmissions preferably comprise audio-video data packet streams, such as MPEG-2 streams. By way of example, the diverse transmission medium may comprise a wireless connection (i.e. WiFi) used in combination with a power-line network connection, such as within a home network.