Patent application number | Description | Published |
20080198234 | Video Signal Loss Detection - Faults resulting in reception of a still, but unknown, frame are recognised by comparing each received frame of the video signal with its predecessor, incrementing a counter in the event that the difference between the frames falls below a threshold; and generating an alarm signal in the event that the count of the counter exceeds a predetermined count. Other types of fault such as loss of signal (i.e. reception of just noise) are recognised by incrementing the counter whenever the difference exceeds a threshold. Similar results may be obtained by instead the monitoring quantisation step size and/or number of transmitted bits of a digitally coded signal, and noting that it falls below, or exceeds, a threshold. A preferred option is to compute a complexity measure, being a monotonically increasing function (e.g the product) of the quantisation step size and of the number of coded bits and compare this with the threshold value. Faults occasioned by receipt of a particular fixed image instead of the wanted picture are recognised by comparing each frame of the video signal with the fixed image, and generating an alarm signal in the event that the difference between the frames consistently falls below a threshold. | 08-21-2008 |
20080205793 | Generating Image Data - The present invention concerns the generation of image data, particularly, though not exclusively for motion estimation in the context of video coders employing inter frame differential coding. A method is provided for generating image data using a set of sampled pixels, the sampled pixels being representative of a sampled image, the method including the steps of: (i) at intermediate positions between sampled pixels, interpolating the sampled pixels so as to provide at least one set of interpolated pixels arranged along a plurality of lines, the or each set of interpolated pixels having a respective offset relative to the sampled pixels, and, (ii) storing the or each set of interpolated pixels with a respective address in a memory, the addresses forming an ordered sequence, wherein along a given line, neighbouring interpolated pixels having the same offset are stored with respective addresses that are consecutive to one another in the ordered sequence. | 08-28-2008 |
20090052531 | VIDEO CODING - A video encoder using inter-frame differential coding has a store ( | 02-26-2009 |
20090116551 | Data streaming system and method - A data streaming system and method typically use a server arranged to stream one of a plurality of encoded data streams to a client. Each of the plurality of data streams may be an independent representation of a common data source encoded at a different resolution to the other of the plurality of data streams. The server can include a transmitter and a first buffer. The transmitter can be arranged to transmit data packets of the encoded data stream to the client via the first buffer. The transmitter can be arranged to monitor the content of the first buffer and switch to transmit another of the plurality of data streams in the event that predetermined criteria are detected from the first buffer. | 05-07-2009 |
20110019738 | VIDEO CODING - Pictures are coded using a coding algorithm with a variable parameter QP so that the quality of the coding varies. First ( | 01-27-2011 |
20110243223 | MULTIPLEXED VIDEO STREAMING - A plurality of video streams is transmitted over a transmission link. At intervals, one determines for each video stream at each of a plurality of encoder settings, having regard to the amount of data buffered at a receiver for that stream, a bit rate sufficient to transmit the remainder of that stream at that encoder setting such as to avoid buffer underflow at the receiver. One determines also a critical point equal to the earliest time at which that bit rate can be reduced while still avoiding buffer underflow at the receiver. An encoder setting is chosen for each video stream such that the sum of said bit rates required for transmission of the streams does not exceed the capacity of the transmission link. Any surplus capacity of the transmission link is allocated to the stream that has the earliest critical point. | 10-06-2011 |
20110292801 | CONTROLLING BANDWIDTH SHARE - There is proposed a modification to the ECN protocol to remove the one-to-one relationship between the network signalling congestion and the sender response to that congestion. The result is to allow a receiver terminal to exhibit some control of bandwidth share relative to other receiver terminals. The idea is to calculate the average CE arrival frequency from received data packets and to set ECE flags at a rate determined as a function of the average CE arrival frequency. Preferably, the function is a multiplier applied to the average CE arrival frequency. The effect of averaging the CE arrival frequency as well as application of a multiplier is a decoupling of the ECE marked ACKs sent by a receiver to the sender, and control of the resulting transmission rate at the sender. | 12-01-2011 |
20110296485 | VIDEO STREAMING - A video sequence is to be transmitted at a selectable quality from a server over a network. A network control protocol operates in response to a control parameter to allocate to the server a share of available transmission capacity in proportion to the value of the control parameter. First, one determines a plurality of transmission rate values that are needed over successive time periods of the sequence for successful transmission of the sequence at a reference quality; then the control parameter is set, proportional to the transmission rate value and communicated to the control protocol at corresponding time instants. The sequences can then be transmitted, encoded at a quality from time to time selected in dependence upon the actual transmission capacity made available by the network to the server. | 12-01-2011 |
Patent application number | Description | Published |
20130111060 | VIDEO STREAMING | 05-02-2013 |
20130185399 | CONTENT DELIVERY - A method for providing equitable media streaming between an HTTP server and a number of receivers via shared network. The streaming data is processed to split the data across a number of sub-streams. Each sub-stream contains non-contiguous data. A receiver requesting the streaming media establishes a number of TCP sessions, one for each sub-stream and the received sub-stream data is reassembled at the receiver so that the streaming media can be presented. | 07-18-2013 |
20130279565 | VIDEO CODING - Methods and apparatus for video coding are disclosed, particularly for use in relation to video compression. Many commercially available video encoders support constant bit-rate encoding but not constant quality encoding. Aspects of the present invention are concerned with methods and apparatus for video coding, the methods involving the determination of bit-rates at which a constant bit-rate encoder may be operated such that segments of video can be chosen from files encoded at the bit-rates so-determined in order to produce an output bitstream in which the quality is nearly constant. Bit-stream segments may be chosen from a low bit-rate bitstream for easy-to-compress scenes, and from a high bit-rate bitstream for hard-to-compress scenes. | 10-24-2013 |
20130291032 | METHOD FOR DELIVERING VIDEO CONTENT ENCODED AT ONE OR MORE QUALITY LEVELS OVER A DATA NETWORK - A client device receives streamed encoded content data, such as encoded video data, which has been encoded at a constant perceptual quality. Several different versions of the content are available to be streamed to the device, at different perceptual quality levels. In order to decide which quality level to request from a content server at intervals the device calculates the delivery rates that would be required for each level of quality. The calculation of the delivery levels is made in dependence on whether the actual delivery rate that has been received so far is greater than or less than a constant bit rate delivery schedule that decreases monotonically but which guarantees to deliver the encoded data in a timely manner such that no buffer underflow and interruption of reproduction takes place. The monotonically decreasing bit rate schedule is defined by one or more “critical points”, which are the points at which the bit rates are decreased, and correspond to the points where the delivery schedule is just equal to the decoding schedule of the encoded data. At such points there would be no encoded data in a buffer at the client. If the delivery rate has been greater than the constant bit rate schedule for a quality then the delivery rate required going forward for a particular quality level can be calculated from the critical point information, and no more complicated calculation is required. | 10-31-2013 |
20130297818 | VIDEO STREAMING OVER DATA NETWORKS - A client device receives streamed encoded content data, such as encoded video data, which has been encoded at a constant perceptual quality. Several different versions of the content are available to be streamed to the device, at different perceptual quality levels. In order to decide which quality level to request from a content server at intervals the device calculates the delivery rates that would be required for each level of quality. The delivery rates are calculated in dependence on so-called critical points, which are points at which a piecewise constant bit rate delivery schedule is just equal to the decoding schedule. There are two classes of critical points, being a first class of critical points, referred to herein as “additional critical points”, which are points on the decoding schedule where, for any particular other point on the decoding schedule before an additional critical point, and assuming that a minimum threshold amount of data is buffered when delivery occurs from the particular point, a constant bit rate delivery schedule that is calculated for the particular point taking into account the buffered minimum amount of data and of such a rate such that buffer underflow does not occur is substantially equal to the decoding schedule. A second class of critical points, referred to herein as “downstairs critical points”, is also defined, which are derived from the decoding schedule as a whole, and which are the points at which a piecewise monotonically decreasing constant bit rate delivery schedule (the so-called “downstairs” schedule), which is calculated such that when delivering the encoded content data from the start buffer underflow does not occur, is substantially equal to the decoding schedule of the encoded content data. When the actual delivery rate received is ahead of the so-called “downstairs” schedule, then the delivery rate required for a particular quality level can be calculated from the second class of critical points. However, when the actual delivery rate received is behind the downstairs schedule, then the delivery rate required is calculated from the first class of critical points. | 11-07-2013 |
Patent application number | Description | Published |
20100150241 | VIDEO CODING - A video signal is coded using predictive coding. The degree of quantisation that is applied is varied as a function of measures of predictive power, the idea being that a picture that is useful as a predictor for other pictures is worth coding well. These measures are formed in a pre-analysis of the pictures to obtain, for each macroblock analysed, a measure that depends on its similarity to a region for which it is a potential predictor. Preferably these measures are cumulative. | 06-17-2010 |
20100246677 | VIDEO CODING - A sequence to be encoded is divided into a plurality of temporal portions or chunks. The sequence is then analysed to determine for each chunk, in accordance with a plurality of encoding quality settings, data establishing the relationship between the quality settings and (i) a quality metric for the portion and (ii) the number of bits generated by encoding the portion at that quality setting. Given a target quality, a target bit rate is then set (or vice versa); then one chooses a set of quality settings, one per chunk, that tends to minimise a combined quality cost for the sequence within the constraint that transmission of encoded video at the target bit rate via transmitting and receiving buffers of specified size and initial receiver buffer fullness shall not cause underflow nor overflow. The combined quality cost is the sum of individual quality costs each of which is a function of the deviation of the quality metric of the respective encoded portion from the target quality, the function being such that the cost generally increases as the absolute value of the deviation increases. The sequence is then encoded using the chosen quality settings. | 09-30-2010 |
20130163667 | VIDEO STREAMING - The network contains one or more network based video servers connected to one or more video receivers over a shared network. Multiple pieces of video content are each encoded at a number of constant quality levels and stored on one or more of the network based servers. In response to requests from a receiver, video content is selected on a server and delivered over the shared network to the receiver. The system selects the quality level of the stream to deliver based on characteristics of the video stream currently being delivered, and the number of bits already buffered at the video receiver and the available network throughput. The aim is to select the video quality being delivered according to the available network throughput so as maximise the quality while ensuring that all video data is delivered over the network in time for it to be decoded and displayed without interruption. The invention proposes a method for making that selection in advance. | 06-27-2013 |
20130322522 | COMPACT CUMULATIVE BIT CURVES - Embodiments of the present invention provide a compact representation of a cumulative bit curve formed from piece-wise straight line approximations between upper and lower bounds about an actual cumulative bit curve (CBC). In one embodiment the lower bounds are found by applying a constraint such that if a delivery rate was to be calculated using the count at the lower bound it would result in a delivery rate which was greater than the delivery rate that would be calculated using the actual CBC data by a particular amount, for example 10%. The actual CBC data is then used as an upper bound. As a result, the approximated CBC will lie for each GoP between the actual CBC value and the lower bound, with the result that one can be certain that any data rate that is calculated using the approximation will be at least as high as a data rate that is calculated using the actual CBC data. In terms of line-fitting algorithms that are used, several different algorithms may be used of differing complexities, with the intention of trying to minimise the number of end-points required of within the piecewise approximation. | 12-05-2013 |
Patent application number | Description | Published |
20090241506 | Gas turbine system and method - A gas turbine system and method is provided. The proposed gas turbine system includes a combustor with at least one burner. The burner has an entry for introducing a fuel into an operating medium composed of a gas containing an oxidant to facilitate combustion of the fuel. In operation, the combustion of the fuel generates a flame and a resulting combustion gas. The provided gas turbine system includes at least one oxygen sensor located downstream of the flame, and measures an oxygen concentration of the combustion gas at that location. Further, the proposed gas turbine system includes a device to determine the temperature of the flame based upon the measured oxygen concentration of the combustion gas at the location of at least one oxygen sensor. | 10-01-2009 |
20090317242 | METHOD AND DEVICE FOR COOLING A COMPONENT OF A TURBINE - A method for cooling a component of a turbine is provided, wherein a fluid with a pressure below 1 bar is guided away from the component. Moreover, a turbine is described comprising a component, a conduit which is connected to the component so that a fluid can be guided away from the component, and a fluid discharge which is connected to the conduit. The fluid discharge is constructed so that it removes a fluid with a pressure below 1 bar. | 12-24-2009 |
20120144833 | Arrangement for Preparation of a Fuel for Combustion - An arrangement for preparation of a fuel for combustion including a burner is provided. The arrangement includes a combustion chamber associated with the burner and in which combustion of a fuel is to take place, as well as means for supplying liquid fuel to the arrangement through an internal passage in the burner for the combustion, solid portions of the burner body being heated by the combustion, wherein the internal passage is located inside the solid portions of the burner body for receiving heat energy evaporating the fuel from these body portions, and that it includes means for conveying vaporized fuel to the combustion chamber to take part in the combustion. | 06-14-2012 |
20130273639 | TREATMENT OF A SECTION OF A FLOW ENGINE - A method that is provided that the at least one section of the flow engine includes at least a part of a combustion chamber of a gas turbine and is treated with at least a component with at least a biocatalytic activity, wherein the least one component with at least a biocatalytic activity is used for degradation of at least a substance with high hydrocarbon content, which is a carbonization arising during a combustion process. The invention further relates to a use of the at least one component with the at least one a biocatalytic activity for the treatment of the at least one section of the flow engine. | 10-17-2013 |
20130298569 | GAS TURBINE AND METHOD FOR OPERATING SAID GAS TURBINE - The present disclosure relates to gas turbine including a combustion system with several burners, a conduit system with a fuel manifold for providing the burners with liquid fuel and a system for aerating the liquid fuel with gas. The system for aerating the liquid fuel with gas is located upstream to the fuel manifold. | 11-14-2013 |
20140020397 | COMBUSTION CHAMBER WITH A WALL SECTION AND A BRIM ELEMENT - A combustion chamber for a gas turbine is proposed. The combustion chamber has a wall section and a brim element. The wall section has an inlet aperture for injecting a cooling medium into the combustion chamber. The brim element is mounted to an inner face of the wall section. The brim element is formed in such a way that a projected area of the brim element onto the inner face along a direction of a normal of the inner face at least partially covers the inlet channel. | 01-23-2014 |
20140060071 | COOLED PILOT FUEL LANCE - A device for injecting fuel into a combustion chamber of a gas turbine is provided, having a distribution section to which a first fuel channel, a second fuel channel and an injection channel are coupled. The first fuel channel and the second fuel channel are arranged such that a) fuel is transportable by one of the first fuel channel and the second fuel channel to the distribution section, and b) a first quantity of fuel is transportable by the other one of the first fuel channel and the second fuel channel out of the distribution section. The injection channel is arranged such that a second quantity of fuel is injectable from the distribution section into the combustion chamber. The device further comprises an end cap with a protrusion having the injection channel inside, and extending inside the inner tube. | 03-06-2014 |
20140219788 | IMPINGEMENT COOLING OF TURBINE BLADES OR VANES - The present invention relates to a turbine assembly with a basically hollow aerofoil, having at least a cavity with an inner wall and having at least an aperture providing access to the cavity, and at least a first impingement device arrangeable within the cavity. The at least first impingement device is self-locking, resilient and preloadable and has at least one locking element to lock the at least first impingement device in place in the cavity via a force fit between the at least one locking element and the inner wall of the cavity wherein the locking element of the at least first impingement device is embodied as a protrusion extending in an assembled state of the at least first impingement device in the cavity basically perpendicular to a surface of a side wall of the at least first impingement device in a direction towards the inner wall. | 08-07-2014 |
20140260292 | GAS TURBINE AND METHOD FOR GUIDING COMPRESSED FLUID IN A GAS TURBINE - A gas turbine having a combustion chamber with exhaust section through which combustion gas is exhaustable, plenum chamber and compressor are provided. The plenum chamber is coupled to the compressor wherein a first quantity of compressed fluid is injectable therein at a radially inner wall of the plenum chamber. A guide vane section with at least one airfoil is coupled to the exhaust section so combustion gas is flowable against the airfoil. The exhaust section and guide vane section are housed inside the plenum chamber. The airfoil has a first flow chamber where a second quantity of compressed fluid is flowable through the guide vane section from the compressor in the direction from the inner wall to a outer wall of the plenum chamber before being discharged. The second quantity of compressed fluid streamable through the guide vane section is larger than the first quantity of the compressed fluid. | 09-18-2014 |