Included is the oxydehydrogenation of saturated dinitriles, for example, succinonitrile, to prepare unsaturated dinitriles, for example, fumaronitrile and maleonitrile. Succinonitrile can be oxydehydrogenated by passing it in a vapor phase over a calcined calcium nickel phosphate catalyst, and the selectivity to fumaronitrile can be varied by the presence of water vapor in the vapor phase feed mixture.

Certain processes for the production of a dinitrile product such as a fumaronitrile or maleonitrile product are known. One, for example, involves oxydehydrogenation.
Kosel et al., U.S. Pat. No. 3,313,840 (1967), disclose a catalytic oxydehydrogenation process for the production of fumaro- and maleonitrile from succinonitrile. The process must be carried out in the presence of at least one oxide which is stable at the reaction temperature of an element of Groups Vb or VIb of the Periodic system, especially vanadium pentoxide, molybdenum trioxide and, particularly, chromium (III) oxide. It is disclosed that the dinitriles are produced in a practically constant ratio of fumaronitrile to maleonitrile of 5:4. A problem with this process can be the frequent regeneration or replacement of the catalyst.
Other processes for the production of a dinitrile product such as a fumaronitrile or maleonitrile product are also known. They generally fall into seven representative types.
The first is dehydration of a diamide of fumaric or maleic acids with phosphorous pentoxide such as taught by Pace, U.S. Pat. No. 2,438,019 (1948). Problems with this include difficulty in synthesizing the reactant diamide and the practical control of the strict reaction conditions.
The second is a 1,2-diiodoethylene and copper cyanide reaction such as taught by Hochwalt, U.S. Pat. No. 2,399,349 (1946). A problem with this is the procurement of special starting materials.
The third is an acetonitrile high temperature dehydrogenation-dimerization with chlorine such as taught by Japanese Patent Publication No. 17965/1967. Problems with this include the practical control of the strict reaction conditions and the corrosive nature of the reaction.
The fourth is a cyanoacetylene and prussic acid reaction such as taught by Morita et al., U.S. Pat. No. 3,959,345 (1976). A problem with this is the procurement of starting materials.
The fifth is oxycyanation, which is a 3-cyano-1-propene and cyanide reaction in the presence of oxygen such as taught by Kominomi et al., Kogyo Kogaku Zasshi, 74, 2464-68 (1971). Problems with this include low selectivity and catalyst coking.
The sixth is a fumaronitrile preparation by a chloro-acrylonitrile and aqueous alkali or alkaline earth cyanide reaction such as taught by Mowry et al., U.S. Pat. No. 2,471,767 (1949). A problem with this is procurement of starting materials and strict reaction conditions.
The seventh is ammoxidation, a process involving an unsaturated compound, ammonia and oxygen. Proposed unsaturated compounds include benzene, cyclohexene, phenol and butadiene such as disclosed by Furuoya et al., U.S. Pat. No. 4,436,671 (1984). Problems with this include production of by-products such as acrylonitrile, acetonitrile and prussic acid.
In addition, the foregoing processes are typically restricted to preparing narrow classes of products, often only the compounds fumaronitrile and maleonitrile. Most are not readily commercially adaptable.
What is lacking and what is needed is a process for preparing a dinitrile product which is simple and direct, a process in which selectivity can be varied by varying process parameters and a process which may prepare a wide variety of dinitriles including, for example, fumaro- and maleonitriles. What is also lacking and what is needed is such a process which may be readily commercializable.


A video recording method is disclosed. The method includes receiving video recording instructions; monitoring an object distance between an object to-be-recorded and a lens of a camera; if the object distance between the object to-be-recorded and the lens is within a first range, controlling a first camera to focus based on the object distance, wherein different object distances within the first range correspond to different focus points; and if the object distance between the object to-be-recorded and the lens is within a second range, controlling a second camera to focus at a hyperfocal length, wherein different object distances within the second range correspond to a same focus point.

With the development of science and technology, an electronic device such as a smartphone, a tablet, a notebook computer, etc., becomes a tool that is essential in people's daily life. Among many functions of the electronic devices such as smartphones, tablets, etc., video recording is one of the most important functions. To improve video recording quality, an electronic device such as a smartphone generally has an automatic focusing function. However, during automatic focusing of a camera, the electronic device often needs to move a lens repeatedly to focus. As such, the electronic device needs to pull out or retract the lens repeatedly, which causes a slow focusing process and impairs user experience.

Video recording method and electronic device


A method of manufacturing a device having a microelectronic component housed in a hermetically sealed vacuum housing, including forming a getter in said housing, pumping out and heating the device to degas elements housed in said housing, after said pumping, hermetically sealing the housing in fluxless fashion.

For certain applications, microelectronic components have to operate in vacuum to achieve the desired performances. This is true, in particular, for non-cooled detectors for infrared imaging based on bolometric microbridges, called "microbolometers" hereafter. In the field of so-called "thermal" infrared detectors, it is indeed known to use one-dimensional or two-dimensional arrays of elements sensitive to infrared radiation, capable of operating at ambient temperature.
A thermal infrared detector conventionally uses the variation of the electric resistivity of a thermometric material, or also known as "bolometric" according to its temperature. The unit sensitive elements of the detector, or "bolometers", are usually in the form of membranes, each comprising a layer of thermometric material, and suspended above a substrate, generally made of silicon, by support arms having a high thermal resistance. Such membranes, collectively called "retina", especially implement a function of absorption of the incident radiation, a function of conversion of the power of the absorbed radiation into thermal power, and a thermometric function of conversion of the generated thermal power into a variation of the resistivity of the thermometric material, such functions being implementable by one or a plurality of different elements. Further, the support arms of the membranes are also electrically conductive and connected to the thermometric layer thereof, and means for sequentially addressing and biasing the thermometric elements of the membranes and means for forming electric signals usable in video formats are usually formed in the substrate having the membranes suspended thereabove.
Such a detector is for example described in document: "Uncooled amorphous silicon technology enhancement for 25 μm pixel pitch achievement"; E. Mottin et al, Infrared Technology and Application XXVIII, SPIE, vol. 4820E.
To make thermal losses by gas convection, which would limit the quality of the detection, negligible, the sensitive retina is usually integrated in a hermetically sealed housing, or housing, under a very low pressure. The housing is provided with a window transparent to radiations of interest, usually having a wavelength between 8 and 14 micrometers. As a variation, each bolometer is integrated in a hermetically sealed micro-housing provided with such a window. The pressure level in the housing is typically adjusted so that losses by convection are smaller than losses by thermal conduction via the support arms, thus ensuring a fine detection. To achieve this, the gas pressure in the housing is thus usually lower than or equal to 10−2 mbar, and preferably lower than 10−4 mbar.
However, obtaining such a pressure level requires specific techniques for the hermetic sealing of the housing. Further, it can be observed that certain materials degas after the sealing into the inner space, or cavity, delimited by the housing. The maintaining of the initial low pressure level in the housing during the detector lifetime, typically 20 years, should thus be ensured despite the degassing of the surfaces and elements internal to the housing.
Referring to the example of FIG. 1, the vacuum sealing of a bolometric detection device usually uses the following sub-assemblies: a base 10 comprising a bottom 12 and lateral walls 14, formed in one piece, bolometric detector 16, usually formed of the sensitive retina integrated on the sense substrate, and a cap transparent to infrared radiation 18, or "window", playing at the same time a role of mechanical protection, of hermetic closing of base 10, and of transparency to infrared radiation. Finally, a getter 20 is also housed in the housing to maintain a sufficient vacuum level despite the degassing of the elements in communication with inner space 22 of housing 24 defined by base 10 and window 18.
Base 10 is usually formed of an assembly of mainly metallic or ceramic materials, and also forms the electric interface of the detector with the outside of the housing by means of connector elements 26. Component 16 is fixed to the bottom of the housing, for example, by gluing, and connected to connection areas 28 reserved for this purpose in housing 24 by a wiring 30 known per se in the state of the art.
Window 18 is assembled on base 10 directly or indirectly by means of an intermediate part, the assembly being formed by a fluxless soldering having operating conditions which limit the degassing of the sub-assemblies just described during the sealing of the window to the base. As known per se, the fluxless soldering requires the presence of non-oxidized metal layers on window 18 and base 10, at the level of surfaces intended for the hermetic junction of these parts. The metal layers are thus usually formed of one or a plurality of layers, at least the last one thereof being made of a noble metal such as gold, or more seldom platinum. Fluxless soldering, which enables to bond metal elements together by atomic diffusion by means of a mechanical action, or more currently by heating until the metal seal at least partially melts, is well known per se and will thus not be described in detail. As known per se, to obtain a good connection between metal elements, for example by welding or soldering, it is preferably for the elements not to be oxidized at their surface. To achieve this, either a deoxidizing material or flux is used, to remove the oxide layer, or the metal elements are non-oxidizable.
Getter 20 is usually made of materials having a strong affinity for the main gas molecules likely to be emitted (degassed) by all the internal surfaces of cavity 22 of the housing. The getter is in particular selected to adsorb H2, N2, O2, H2O, and volatile carbon compounds (called organic) such as, for example, CH4. Typical materials used for the getter are, as well known, alloys based on elements Zr, Ti, Co, Fe, or Ba. Getter 20 usually appears either in the form of sintered blocks fixed to the inside of cavity 22, or in the form of one or of a plurality of thin layers deposited on strips, plates, or mineral substrates by means of evaporation or of cathode sputtering techniques, integrated in cavity 22 on assembly of component 16 in housing 24.
As known per se, a getter used in this type of application requires being activated to be able to adsorb the previously-indicated gases, the activation comprising making the getter surface reactive by means of an adapted thermal cycle carried out in vacuum. A getter 20 in the form of thin films, having a thickness in the range from one to a few micrometers generally requires a thermal activation at a much lower temperature than a sintered getter. Thus, known thin-film getters can be activated by simple heating of the device just described at a temperature in the range from 350° C. to 400° C. once the housing has been sealed.
Sintered getters require a temperature in the order of 800° C. or more, so that a general heating of the tight housing at this temperature would cause irreparable damage. The activation of a sintered getter is thus performed by Joule effect by means of electric connections provided for this purpose, which enables to substantially only heat the getter. The activation of such a getter however induces an intense radiation capable of damaging the bolometers. Further, a thin-film getter is usually preferred since it requires no electric connection accessible from the outside of the housing. This character simplifies the architecture, and thus the manufacturing process, and thus decreases the cost of the housing. Indeed, the connections crossing the base of the housing may raise tightness problems and induce significant design constraints due to the high intensities to be applied during the activation to generate the necessary high temperatures.
However, a thin-film getter is a constraint for the general device manufacturing method, since the getter efficiency is all the better as the activation temperature is high, even though it remains within a lower range, as specified. Actually, this specific thermal activation step, generally formed on the entire device, always defines the maximum temperature point to which the electronic component is submitted during its manufacturing cycle. In other words, the complete design of the component, and generally all the portions of the device, are actually directly dependent on the characteristics of the thin-film getter used.

Method for manufacturing a device comprising a hermetically sealed vacuum housing and getter

Abstract: Further, each material forming the device likely to degas into the inner space is a mineral material, the getter is capable of substantially trapping hydrogen only and is inert to oxygen and/or to nitrogen and the heating and the sealing are performed at a temperature lower than 300° C.


A staged CMOS output buffer has multiple output transistors connected in parallel and driven by corresponding predrivers. Each predriver has a first input from which an inactive output transistor can be turned on, and a second input from which the other, active output transistor can be turned off. The input to the output buffer is coupled directly to the second input of both predrivers to turn the output transistors off when switching begins, and a resistor-capacitor (RC) circuit is inserted between the first inputs to stagger the predriver turn-on times to reduce the peak and slope of the switching current. The predriver employs chains of pass transistors to achieve both tri-state functionality and the simultaneous turn-off necessary for the staged configuration. A split termination is also employed to reduce switching current, especially NMOS-PMOS crossover current.

In the field of integrated circuits (ICs) , there is a widely-recognized phenomenon that has been responsible for problems appearing in the systems in which the ICs operate. When an output of an IC begins to switch, the instantaneous current through the output buffer in the IC changes very suddenly. This is particularly so for CMOS output buffers, which have very large current transients when they begin to switch. When numerous IC outputs switch simultaneously, the amount of current in the power supply leads of the IC also changes suddenly to meet the demand. This sudden change can cause a significant voltage drop to develop across stray inductance present in the IC's power-distribution network, especially in package leads and bonding wires . If this voltage drop is large enough, it may cause erroneous circuit operation and the loss of stored data. This problem is therefore potentially very severe, and must be addressed in every IC design, particularly those having numerous outputs or driving large external loads. Although it has many names, this problem is herein referred to as "di/dt noise", because of its relationship to the rate of change of current in the output buffer.
There have been many different approaches to reducing di/dt noise. One general approach involves controlling the switching rate, or slew rate, of the output buffers. In this approach, the output buffer is designed so that it cannot turn completely on all at once; rather, it turns on more gradually so that the peak current and its rate of change are reduced.
Within this class of slew-rate controlled output buffers, there is a sub-class of buffers that employ a number of smaller buffers wired in parallel and some means of staggering their switching times. These are referred to herein as "staged buffers" because they turn on in stages. While the final drive current of a staged buffer equals that of the single large buffer it replaces, the transient current is reduced because only one of the smaller buffers is switching at a time.
Before the merits of known staged buffers are discussed, an additional phenomenon must be introduced. One problem that must be addressed in any CMOS buffer, and particularly in a staged buffer, is that of excessive crossover current flowing directly between the pull-up and pull-down transistors in the buffer. Consider a buffer having two pull-up devices in parallel and two pull-down devices in parallel, and some delay element between their gates so that their switching times are staggered. In the interval between the switching of the first and second stages, one transistor from the first stage (for example, the pull-down transistor) will be on at the same time that the opposite transistor in the second stage (in this case, the pull-up transistor) is also on. In such a case, a large crossover current will flow directly through both of those transistors and the power distribution network of the IC, contributing to switching noise. To avoid this problem, staged buffers often have some means for turning off all stages simultaneously, and then turning them on sequentially. By doing this, no stage is driving against another stage when it turns on, and crossover current is kept to a minimum.
One example of a staged buffer can be found in U.S. Pat. No. 5,111,075 issued May 5, 1992 to Ferry et al. and entitled "Reduced Switching Noise Output Buffer Using Diode for Quick Turn-Off". In this scheme, resistors are connected in series between the gates of the staged output transistors. The resistor-capacitor (RC) circuit formed by each resistor and the transistor gate in the following stage provides the necessary incremental turn-on delay. A set of diodes is connected between the buffer input and the gates of the transistors in each stage to turn all stages off simultaneously when the input switches.
Buffers such as that of Ferry rely on the gate capacitance of the output transistors to create the desired RC delay. Typically the output transistors have minimum-length gates to minimize their propagation delay. But as a result, their gate capacitance can vary widely with processing, so that the resulting RC delay is also inconsistent. If the gate were made longer so that its capacitance were more consistent, then the propagation delay of the buffer would increase. Another drawback of relying on output transistor gate capacitance is an undesirable feedback effect: faster transistors generate greater current peaks, so it is desirable to space their switching times; but faster transistors also have lower gate capacitances, so that the RC delay is reduced, bringing their switching times closer together. As a result, switching noise in the faster buffers, which are the most problematic to begin with, is not reduced as much as in slower ones.
Another example of a staged buffer can be found in U.S. Pat. No. 4,961,010 issued Oct. 2, 1990 to Davis, entitled "Output Buffer for Reducing Switching Induced Noise". Like the buffer of Ferry, this buffer uses resistors between the gates of the output transistors to achieve the desired delay. It also uses additional transistors connected to the gates of the output transistors to achieve simultaneous turn-off. The buffer of Davis is also a tri-state buffer; the tri-state circuitry therein is conventional and largely independent of the staging or delay circuitry.
Yet another example of a staged buffer can be found in U.S. Pat. No. 4,987,324 issued Jan. 22, 1991 to Wong et al., entitled "High-Speed CMOS Buffer with Controlled Slew Rate". Wong's buffer employs control inverters preceding each stage. Each control inverter has a different switching threshold, so that the stages switch in a desired sequence to minimize both di/dt and crossover current. The delay between stages is a function of both the inverter switching threshold and the edge rate of the input signal, which in turn are both sensitive to process variations. This scheme also cannot easily be extended to more than two stages if such an extension were to be found desirable.


According to the present invention, there is provided an improved refreshable tactile display apparatus including a housing, bias compression springs, sliding blocks, pins, and a shape memory alloy wire. The sliding block is actuated by the interaction between the bias compression spring and the shape memory alloy wire. The shape memory alloy wire is then activated by current driven from a power supply in either a modulated or unmodulated fashion.

1. Field of the Invention
The present invention generally relates to the field of refreshable tactile displays. More specifically, the present invention relates to an improved refreshable Braille display for use by the visually impaired.
2. Description of Related Art
Braille is the method that visually impaired individuals use to read and write. It consists of letters, numbers, and symbols represented as distinct patterns of dots. A refreshable Braille display is a device that is capable of refreshing or changing a pattern of Braille dots as the user reads each line from the display. Generally, such a display utilizes only one line of characters that can constantly change. Most current refreshable Braille displays use 20, 40 or 80 characters, or cells, of Braille for the line of text.
Currently available refreshable Braille displays generally use a piezoelectric (PZT) reed to actuate the dots using an electric field. While mechanically effective, this method of actuation is very expensive, has a high rate of scrapped material, and needs a significant amount of tedious hand assembly and wiring, resulting in substantial manufacturing costs. The cost of Braille displays are generally proportional to the number of cells of 8 dots that they contain. The prices of displays range anywhere from 1,600 dollars for a 20 cell display, to 7,000 dollars for a full 80 cell display. These steep costs have prevented many visually impaired individuals from having access to such displays.
As such, there exists a significant need for an improved refreshable Braille display that is constructed in a way which provides a cost-effective actuation method and greatly reduces the costs and complexity of manufacture.

Actuation mechanism for braille displays

Board of Trustees of Northern Illinois University


A computer-implemented method for blocking and removing Internet-traversing malware may include: 1) identifying a persistent storage object of an Internet client application, 2) identifying an attempt by an executable object to access the persistent storage object, 3) determining that the executable object is not authorized to access the persistent storage object, and then 4) performing a security action based on the determination. Various other methods, systems, and computer-readable media are also disclosed.

Internet users increasingly use a variety of social networking websites to connect with friends, family, and professional contacts, as well as with communities of people with shared interests, concerns, or beliefs. Many social networking sites benefit users by enabling users to exchange information with others whom they trust or respect. Unfortunately, malware authors may seek to exploit this trust for their own ends.
For example, some malware threats (such as KOOBFACE and SAMY) may, upon infecting a user's machine, harvest session tokens for one or more social networking sites from browser cookies stored on the user's machine. The malware may then use these session tokens to submit malicious or unwanted content to social networking sites under the user's account. For example, the malware may post a fake message under the user's account that urges the user's friends to follow a link that points to a copy of the malware (e.g., an apparently benign software installer that may install the malware on the victim's computer).
Security software may attempt to combat malware of this type by scanning executable files for signatures of the malware (i.e., patterns indicating the presence of malware), both to prevent users from disseminating the malware and to prevent the users' friends from downloading and installing the malware. However, changes to the malware (e.g., via polymorphism) or new threats may prevent security systems from identifying the malware until security system vendors update their signature databases.

Systems and methods for blocking and removing internet-traversing malware


Systems and methods include a wind detector to receive audio input signals and output a wind detection flag including a single channel wind detection flag and a cross channel wind detection flag, each wind detection flag indicating a presence or absence of wind noise, and a fusion smoothing module to receive the plurality of wind detection flags and generate an output wind detection flag. Microphones generate the plurality of audio input signals. The wind detector and the fusion smoothing module may comprise program instructions stored in the memory for execution by a digital signal processor. The wind detector is a single channel detector to receive a single audio channel of the audio input signal and generate the single channel wind noise flag, and a cross-channel detector to compute auto correlations and a cross correlation between two or more audio channels.

Audio processing devices generally include one or more microphones to sense sounds from the environment and produce corresponding audio signals. An active noise cancellation (ANC) headphone, for example, includes a reference microphone to generate an anti-noise signal that is approximately equal in magnitude, but opposite in phase, to the sensed ambient noise. The ambient noise and the anti-noise signal cancel each other acoustically, allowing the user to hear a desired audio signal.
Conventional ANC systems (and other noise reduction or cancellation systems) do not, however, completely cancel all noise, leaving residual noise and/or generating audible artefacts that may be distracting to the user. For example, unlike ambient sounds cancelled in an ANC system, wind noise may occur at the microphone in response to local air turbulence at the microphone components. Wind noise may not be correlated to the ambient noise that reaches the user's ear canal, and the corresponding anti-noise signal may be audible to the user. Noise suppression systems that attempt to remove background noise from an audio signal face similar challenges in removing wind noise.
In view of the foregoing, there is a continued need for improved noise reduction and noise cancellation systems and methods for audio signals that may include sensed wind noise. There is also a continued need for improved active noise cancellation systems and methods for headphones, earbuds and other personal listening devices that may operate in windy environments.

Wind noise detection systems and methods


A pipeline/subranging architecture is used to provide a circuit for analog to a digital conversion. A course analog to digital converter, a fine analog to digital to converter, combining logic circuitry and a digital to analog converter are used, together with a voltage to current converter and a current to voltage converter. A residual signal is formed as the difference between the input signal and an output signal of the coarse analog to digital conversion, the latter output signal having been converted to analog form by the analog to digital converter. The residual signal is then scaled appropriately and applied to the fine analog to digital converter. A final output signal is based on the output signals of the coarse digital to analog converter and the fine digital to analog converter.

The present invention relates to an analogue to digital converter.
High speed and high resolution are highly desirable features when designing analogue to digital converters (ADCs). The latest ADCs are the 12 bit 65 MS/s level converters, one example of which is Philips model TDA 8767/8. It is desirable to achieve 14 bit or higher accuracy.
One known approach to achieving high speed and high resolution is to use calibration, i.e. to store non-linearity information and digitally correct the ADC on-line. This requires large amounts of digital and memory circuitry and also the ADC must be off-line while the calibration signal is generated and this is undesirable.
Another approach is to use a ladder resistor combined with offset compensated amplifiers in a two or three step 14 bit ADC. Problems arise in realizing ladder resistors accurately and the noise levels tend to be higher than desirable.
Yet a further approach is to use the static linearity of a current DAC (digital to analogue converter). For example, a known such implementation comprises:
a sample and hold circuit;
a coarse analogue to digital converter (ADC);
a digital to analogue converter (DAC);
combining logic circuitry; and
a fine analogue to digital converter (ADC).
This is a known as basic pipeline/subranging architecture. However, major problems arise in matching the DAC with the inter-stage gain and with the range of fine ADCs and offsets and the speed and resolution of known implementations have been limited.
The present invention aims to provide an ADC with high speed and high resolution without the disadvantages of the known implementations described above.
According to the present invention there is provided a circuit for analogue to digital conversion comprising;
a sample and hold circuit;
a coarse analogue to digital converter;
a digital to analogue converter;
combining logic circuitry;
a fine analogue to digital converter; characterized by
a voltage to current converter (R1);
means for subtracting in the current domain;
means for summing at a virtual earth node; and
means for converting current to voltage at the input to the fine analogue to digital converter.
According to a preferred embodiment the subtracting means comprises a current digital to analogue converter and preferably a matched unit current cell.
Preferably the fine analogue to digital converter additionally comprises a resistor matched to the means for converting current to voltage, and a current source matched to the current of the digital to analogue converter current cells.
According to a further aspect of the invention there is provided a plurality of pairs of voltage to current and current to voltage converters connected in cascade formation. Hence the ladder of the second ADC will only approximately determine the range and the second ADC and will drive another series of matched current sources.
According to a preferred embodiment of the further aspect of the invention, a plurality of sample and hold circuits are provided. This has the advantage of increasing the sample rate of the circuit.
An implementation according to the invention, enables a reduction in the number of components to be matched is reduced and the level of matching is reduced to the subrange accuracy.


The long filter decision in VVC is modified by adding at least one gradient check that at least includes sample p6 or q6. This makes it possible to avoid using the long filters when there is some natural structure at sample p6 or q6. In one specific embodiment at least two gradient checks including both q6 and p6 are added. In another embodiment, the dpq threshold is modified from beta>>2 to beta>>4. This threshold change embodiment may be used in conjunction with or instead of the embodiment in which a gradient check that includes p6 and/or q6 is added to the long filter decision.

A video sequence consists of a series of images where each image consists of one or more components. Each component can be described as a two-dimensional rectangular array of sample values. It is common that an image in a video sequence consists of three components; one luma component Y where the sample values are luma values and two chroma components Cb and Cr, where the sample values are chroma values. Other examples include Y′ Cb Cr, Yuv and ICTCP. In ICTCP, I is the "intensity luma" component. For the remainder of this document we will refer to any luma component Y′, Y or I as Y or simply luma. It is common that the dimensions of the chroma components are smaller than the luma components by a factor of two in each dimension. For example, the size of the luma component of an HD image would be 1920×1080 and the chroma components would each have the dimension of 960×540. Components are sometimes referred to as color components.
A "block" is a two-dimensional array of samples. In video coding, each component is split into one or more blocks and the coded video bitstream is a series of blocks. It is common in video coding that an image is split into units that cover a specific area of the image. Each unit consist of all blocks from all components that make up that specific area and each block belongs fully to one unit. The macroblock in H.264 and the Coding unit (CU) in HEVC are examples of units.
In HEVC, each image is partitioned into coding tree units (CTU). A CTU consist of an N×N block of luma samples and two M×M corresponding chroma blocks. A CTU in HEVC is like macroblocks in H.264 and earlier standards but in contrast to macroblocks the CTU size is configurable. Most often, however, the CTU size in HEVC is set to 64×64 luma samples. Each CTU can be recursively quadtree split. The root of the quadtree is then associated with the CTU. The quadtree is split until a leaf is reached, which is referred to as the coding unit (CU). A CU in HEVC always consist of a luma block with equal height and width. How each CTU is split is conveyed in the bitstream. The CU is further the root node of two other trees, the prediction tree that has prediction units (PUs) as nodes and the transform tree that has transform units (TUs) as nodes. Some decoding processes in HEVC are done on the CU level, some are done on the PU level and some on TU level. Boundaries between PUs and boundaries between TUs are filtered by a deblocking filter to reduce discontinuities between TUs and PUs. In HEVC there exist two kinds of prediction types for a PU, intra prediction which only uses prediction from previously decoded samples of the current image for prediction, and inter prediction which uses prediction form at least one previously decoded image.
In HEVC, deblocking is first applied on vertical boundaries and then on horizontal boundaries. The boundaries are either TU boundaries or PU boundaries. To enable parallel friendly deblocking, the deblocking is performed on an 8×8 sample grid.
A deblocking filter strength parameter (bs) is set for each boundary. If the value of bs is larger than 0, then deblocking may be applied. The larger the boundary strength is, the stronger filtering is applied. First it is checked if any of the blocks at a PU boundary between the blocks is an intra predicted block then (bs is set to =2), or if both blocks use inter prediction but and they use different reference frames or have significantly different motion vectors then (bs is set to =1). It is also checked if a TU boundary between the blocks has non-zero transform coefficients in at least one of the blocks (code block flag CBF equal to 1), then (bs is set to =1). This first check sets a boundary strength (bs) which is larger than 0 to indicate that deblocking should be applied. The larger the boundary strength is the stronger filtering is applied. To reduce/avoid removing natural structures when deblocking, a check that there are not any natural structures on respective sides of the boundary is then applied for luma. In HEVC, gradient calculations are used on respective sides of the boundary using the following inequality: abs(p0−2*p1+p2)+abs(q0−2*q1+q2)<beta, where beta (also denoted "β") is a parameter based on the quantization parameter for the block and p0, p1, to p2 are samples on one side of the block boundary and q0, q1, to q2 are samples on the other side of the block boundary. The condition is checked at two positions along the boundary, and if both conditions are fulfilled, then the luma samples are deblocked for that 4 sample part of the boundary. Chroma boundaries may always be filtered if one any of the neighbouring blocks are intra coded.
In the current draft of the specification for VVC (VVC draft 6 JVET-O2001-v14) a coding tree unit (CTU) is similar to the CTU in HEVC with the difference that the CTU in H.266 has a size of 128×128 luma samples. In VVC, the CTU can be split more flexibly such that a resulting CUs may consist of a rectangular luma block. In VVC, there is no prediction tree or transform tree as in HEVC. However, a CU in VVC can be divided into a multiple of TUs or into a multiple of prediction subblocks.
In the current draft of the specification for VVC (VVC draft 6 JVET-O2001-v14), the deblocking is applied on an 4×4 grid for CUs first on vertical boundaries (CU/implicit TU/prediction sub-block boundaries) and then on horizontal boundaries (CU/implicit TU/prediction sub-blocks). Prediction sub-block boundaries inside a CU is filtered on an 8×8 grid. The deblocking is based on HEVC deblocking but also have longer deblocking filters if the size orthogonal to the block boundary is equal to or larger than 32 on at least one side for luma and the other side is larger than 4, modifying at most 7 samples (reading at most 8 samples), if the size orthogonal to the block boundary is less than 32 for one side for luma it modifies at most 3 samples and reading at most 4 samples on that side, and if it is equal to or larger than 8 on both side of a boundary in chroma samples for chroma modifying at most 3 chroma samples and reading at most 4 chroma samples otherwise it modifies at most one sample and reading at most two samples on respective side of the boundary.
The VVC specification (JVET-O2001-v14) has long filters and decisions specified in section 8.8.3 Deblocking filter process.
The deblocking decisions are computed for line 0 and line 4 for segments of for lines.
FIG. 3 show a boundary between first block 302 (denoted the "P block") and a second block 304 (denoted the "Q block") for 4 lines, line 0 to line 3, and for eight sample, samples 0 to 7, for each line and block.
The following is an excerpt from The VVC specification (JVET-O2001-v14). This excerpt is directed to the long filter decision.
Begin Excerpt
22.214.171.124.1 Decision Process for Luma Block Edges
. . .
The following ordered steps apply:
                1. The variables dp0, dp3, dq0 and dq3 are derived as follows:dp0=Abs(p2,0−2*p1,0+p0,0)  (8-1077)dp3=Abs(p2,3−2*p1,3+p0,3)  (8-1078)dq0=Abs(q2,0−2*q1,0+q0,0)  (8-1079)dq3=Abs(q2,3−2*q1,3+q0,3)  (8-1080)        2. When maxFilterLengthP and maxFilterLengthQ both are equal to or greater than 3 the variables sp0, sq0, spq0, sp3, sq3 and spq3 are derived as follows:sp0=Abs(p3,0−p0,0)  (8-1081)sq0=Abs(q0,0−q3,0)  (8-1082)spq0=Abs(p0,0−q0,0)  (8-1083)sp3=Abs(p3,3−p0,3)  (8-1084)sq3=Abs(q0,3−q3,3)  (8-1085)spq3=Abs(p0,3−q0,3)  (8-1086)        3. The variables sidePisLargeBlk and sideQisLargeBlk are set equal to 0.        4. When maxFilterLengthP is greater than 3, sidePisLargeBlk is set equal to 1:        5. When maxFilterLengthQ is greater than 3, sideQisLargeBlk is set equal to 1:        6. When edgeType is equal to EDGE_HOR and (yCb+yBl) % CtbSizeY is equal to 0, sidePisLargeBlk is set equal to 0.        7. The variables dSam0 and dSam3 are initialized to 0.        8. When sidePisLargeBlk or sideQisLargeBlk is greater than 0, the following applies:                    a. The variables dp0L, dp3L are derived and maxFilterLengthP is modified as follows:                            If sidePisLargeBlk is equal to 1, the following applies:dp0L=(dp0+Abs(p5,0−2*p4,0+p3,0)+1)>>1  (8-1087)dp3L=(dp3+Abs(p5,3−2*p4,3+p3,3)+1)>>1  (8-1088)                Otherwise, the following applies:dp0L=dp0  (8-1089)dp3L=dp3  (8-1090)maxFilterLengthP=3  (8-1091)                                    b. The variables dq0L and dq3L are derived as follows:                            If sideQisLargeBlk is equal to 1, the following applies:dq0L=(dq0+Abs(q5,0−2*q4,0+q3,0)+1)>>1  (8-1092)dq3L=(dq3+Abs(q5,3−2*q4,3+q3,3)+1)>>1  (8-1093)                Otherwise, the following applies:dq0L=dq0  (8-1094)dq3L=dq3  (8-1095)                                    c. The variables dpq0L, dpq3L, and dL are derived as follows:dpq0L=dp0L+dq0L  (8-1096)dpq3L=dp3L+dq3L  (8-1097)dL=dpq0L+dpq3L  (8-1098)            d. When dL is less than β, the following ordered steps apply:                            i. The variable dpq is set equal to 2*dpq0L.                ii. The variable sp is set equal to sp0, the variable sq is set equal to sq0 and the variable spq is set equal to spq0.                iii. The variables p0 p3 q0 and q3 are first initialized to 0 and then modified according to sidePisLargeBlk and sideQisLargeBlk as follows:                                    When sidePisLargeBlk is equal to 1, the following applies:p3=p3,0  (8-1099)p0=pmaxFilterLengthP,0  (8-1100)                    When sideQisLargeBlk is equal to 1, the following applies:q3=q3,0  (8-1101)q0=qmaxFilterLengthQ,0  (8-1102)                                                iv. For the sample location (xCb+xBl, yCb+yBl), the decision process for a luma sample as specified in clause 22.214.171.124.5 is invoked with the sample values p0, p3, q0, q3, the variables dpq, sp, sq, spq, sidePisLargeBlk, sideQisLargeBlk, β and tC as inputs, and the output is assigned to the decision dSam0.                v. The variable dpq is set equal to 2*dpq3L.                vi. The variable sp is set equal to sp3, the variable sq is set equal to sq3 and the variable spq is set equal to spq3.                vii. The variables p0 p3 q0 and q3 are first initialized to 0 and are then modified according to sidePisLargeBlk and sideQisLargeBlk as follows:                                    When sidePisLargeBlk is equal to 1, the following applies:p3=p3,3  (8-1103)p0=pmaxFilterLengthP,3  (8-1104)                    When sideQisLargeBlk is equal to 1, the following applies:q3=q3,3  (8-1105)q0=qmaxFilterLengthQ,3  (8-1106)                                                viii. When edgeType is equal to EDGE_VER for the sample location (xCb+xBl, yCb+yBl+3) or when edgeType is equal to EDGE_HOR for the sample location (xCb+xBl+3, yCb+yBl), the decision process for a luma sample as specified in clause 22.214.171.124.5 is invoked with the sample values p0, p3, q0, q3, the variables dpq, sp, sq, spq, sidePisLargeBlk, sideQisLargeBlk, β and tC as inputs, and the output is assigned to the decision dSam3.                                                9. The variables dE, dEp and dEq are derived as follows:                    If dSam0 and dSam3 are both equal to 1, the variable dE is set equal to 3, dEp is set equal to 1, and dEq is set equal to 1.            Otherwise, the following ordered steps apply:            a. The variables dpq0, dpq3, dp, dq and d are derived as follows:dpq0=dp0+dq0  (8-1107)dpq3=dp3+dq3  (8-1108)dp=dp0+dp3  (8-1109)dq=dq0+dq3  (8-1110)d=dpq0+dpq3  (8-1111)            b. The variables dE, dEp, dEq, sidePisLargeBlk and sideQisLargeBlk are set equal to 0.            c. When d is less than β and both maxFilterLengthP and maxFilterLengthQ are greater than 2, the following ordered steps apply:                            i. The variable dpq is set equal to 2*dpq0.                ii. The variable sp is set equal to sp0, the variable sq is set equal to sq0 and the variable spq is set equal to spq0.                iii. For the sample location (xCb+xBl, yCb+yBl), the decision process for a luma sample as specified in clause 188.8.131.52.5 is invoked with the variables p0, p3, q0, q3 all set equal to 0, the variables dpq, sp, sq, spq, sidePisLargeBlk, sideQisLargeBlk, β and tC as inputs, and the output is assigned to the decision dSam0.                iv. The variable dpq is set equal to 2*dpq3.                v. The variable sp is set equal to sp3, the variable sq is set equal to sq3 and the variable spq is set equal to spq3.                vi. When edgeType is equal to EDGE_VER for the sample location (xCb+xBl, yCb+yBl+3) or when edgeType is equal to EDGE_HOR for the sample location (xCb+xBl+3, yCb+yBl), the decision process for a sample as specified in clause 188.8.131.52.5 is invoked with the variables p0, p3, q0, q3 all set equal to 0, the variables dpq, sp, sq, spq, sidePisLargeBlk, sideQisLargeBlk, β and tC as inputs, and the output is assigned to the decision dSam3.                                    d. When d is less than β, the following ordered steps apply:                            i. The variable dE is set equal to 1.                ii. When dSam0 is equal to 1 and dSam3 is equal to 1, the variable dE is set equal to 2.                iii. When maxFilterLengthP is greater than 1, and maxFilterLengthQ is greater than 1, and dp is less than (β+(β>>1))>>3, the variable dEp is set equal to 1.                iv. When maxFilterLengthP is greater than 1, and maxFilterLengthQ is greater than 1, and dq is less than (β+(β>>1))>>3, the variable dEq is set equal to 1.
TABLE 8-18Derivation of threshold variables β′ and tC′ from input QQ012345678910111213141516β′00000000000000006tC′00000000000000000Q1718192021222324252627282930313233β′7891011121314151617182022242628tC′03444455557789101011Q3435363738394041424344454647484950β′3032343638404244464850525456586062tC′1314151719212425293336414551576471Q515253545556575859606162636465β′64666870727476788082848688——tC′80891001121251411571771982222502803143523922.214.171.124.2 Filtering Process for Luma Block Edges. . .Depending on the value of edgeType, the following applies:                If edgeType is equal to EDGE_VER, the following ordered steps apply:. . .3. When dE is equal to 3, for each sample location (xCb+xBl, yCb+yBl+k), k=0 . . . 3, the following ordered steps apply:        a. The filtering process for a luma sample using long filters as specified in clause 184.108.40.206.7 is invoked with the sample values pi,k, qj,k with i=0 . . . maxFilterLengthP and j=0 . . . maxFilterLengthQ, the locations (xPi, yPi) set equal to (xCb+xBl−i−1, yCb+yBl+k) with i=0 . . . maxFilterLengthP−1 and (xQj, yQj) set equal to (xCb+xBl+j, yCb+yBl+k) with j=0 . . . maxFilterLengthQ−1, the variables maxFilterLengthP, maxFilterLengthQ and tC as inputs and the filtered samples values pi′ and qj′ as outputs.        b. The filtered sample values pi′ with i=0 . . . maxFilterLengthP−1 replace the corresponding samples inside the sample array recPicture as follows:recPicture[xCb+xBl−i−1][yCb+yBl+k]=pi′  (8-1116)        c. The filtered sample values qj′ with j=0 . . . maxFilterLengthQ−1 replace the corresponding samples inside the sample array recPicture as follows:recPicture[xCb+xBl+j][yCb+yBl+k]=qj′  (8-1117). . .        Otherwise (edgeType is equal to EDGE_HOR), the following ordered steps apply:. . .3. When dE is equal to 3, for each sample location (xCb+xBl+k, yCb+yBl), k=0 . . . 3, the following ordered steps apply:        a. The filtering process for a luma sample using long filters as specified in clause 220.127.116.11.7 is invoked with the sample values pi,k, qj,k with i=0 . . . maxFilterLengthP and j=0 . . . maxFilterLengthQ, the locations (xPi, yPi) set equal to (xCb+xBl+k, yCb+yBl−i−1) with i=0 . . . maxFilterLengthP−1 and (xQj, yQj) set equal to (xCb+xBl+k, yCb+yBl+j) with j=0 . . . maxFilterLengthQ−1, the variables maxFilterLengthP, maxFilterLengthQ, and the variable tC as inputs, and the filtered sample values pi′ and qj′ as outputs.        b. The filtered sample values pi′ with i=0 . . . maxFilterLengthP−1 replace the corresponding samples inside the sample array recPicture as follows:recPicture[xCb+xBl+k][yCb+yBl−i−1]=pi′  (8-1122)        c. The filtered sample values qj′ with j=0 . . . maxFilterLengthQ−1 replace the corresponding samples inside the sample array recPicture as follows:recPicture[xCb+xBl+k][yCb+yBl+j]=qj′  (8-1123). . .22.214.171.124.5 Decision Process for a Luma SampleInputs to this process are:        the sample values p0, p3, q0 and q3,        the variables dpq, sp, sq, spq, sidePisLargeBlk, sideQisLargeBlk, β and tC.Output of this process is the variable dSam containing a decision.The variables sp and sq are modified as follows:        When sidePisLargeBlk is equal to 1, the following applies:sp=(sp+Abs(p3−p0)+1)>>1  (8-1158)        When sideQisLargeBlk is equal to 1, the following applies:sq=(sq+Abs(q3−q0)+1)>>1  (8-1159)The variable sThr is derived as follows:        If sidePisLargeBlk is equal to 1 or sideQisLargeBlk is equal to 1, the following applies:sThr=3*β>>5  (8-1160)        Otherwise, the following applies:sThr=β>>3  (8-1161)The variable dSam is specified as follows:        If all of the following conditions are true, dSam is set equal to 1:                    dpq is less than (β>>2),            sp+sq is less than sThr,            spq is less than (5*tC+1)>>1.                        Otherwise, dSam is set equal to 0.8.8.3.6.6 Filtering Process for a Luma Sample Using Short FiltersInputs to this process are:        the sample values pi′ and qj′ with i=0 . . . 3,        the locations of pi and qi, (xPi, yPi) and (xQi, yQi) with i=0 . . . 2,        a variable dE,        the variables dEp and dEq containing decisions to filter samples p1 and q1, respectively,        a variable tC.Outputs of this process are:        the number of filtered samples nDp and nDq,        the filtered sample values pi′ and qj′ with i=0 . . . nDp−1, j=0 . . . nDq−1.Depending on the value of dE, the following applies:        If the variable dE is equal to 2, nDp and nDq are both set equal to 3 and the following strong filtering applies:p0′=Clip3(p0−3*tC,p0+3*tC,(p2+2*p1+2*p0+2*q0+q1+4)>>3)  (8-1162)p1′=Clip3(p1−2*tC,p1+2*tC,(p2+p1+p0+q0+2)>>2)  (8-1163)p2′=Clip3(p2−1*tC,p2+1*tC,(2*p3+3*p2+p1+p0+q0+4)>>3)  (8-1164)q0′=Clip3(q0−3*tC,q0+3*tC,(p1+2*p0+2*q0+2*q1+q2+4)>>3)  (8-1165)q1′=Clip3(q1−2*tC,q1+2*tC,(p0+q0+q1+q2+2)>>2)  (8-1166)q2′=Clip3(q2−1*tC,q2+1*tC,(p0+q0+q1+3*q2+2*q3+4)>>3)  (8-1167)        Otherwise, nDp and nDq are set both equal to 0 and the following weak filtering applies:                    The following applies:Δ=(9*(q0−p0)−3*(q1−p1)+8)>>4  (8-1168)            When Abs(Δ) is less than tC*10, the following ordered steps apply:                            The filtered sample values p0′ and q0′ are specified as follows:Δ=Clip3(−tC,tC,Δ)  (8-1169)p0′=Clip1Y(p0+Δ)  (8-1170)q0′=Clip1Y(q0−Δ)  (8-1171)                When dEp is equal to 1, the filtered sample value p1′ is specified as follows:Δp=Clip3(−(tC>>1),tC>>1,(((p2+p0+1)>>1)−p1+Δ)>>1)  (8-1172)p1′=Clip1Y(p1+Δp)  (8-1173)                When dEq is equal to 1, the filtered sample value q1′ is specified as follows:Δq=Clip3(−(tC>>1),tC>>1,(((q2+q0+1)>>1)−q1−Δ)>>1)  (8-1174)q1′=Clip1Y(q1+Δq)  (8-1175)                nDp is set equal to dEp+1 and nDq is set equal to dEq+1.When nDp is greater than 0 and one or more of the following conditions are true, nDp is set equal to 0:                                                cu_transquant_bypass_flag of the coding unit that includes the coding block containing the sample p0 is equal to 1.        pred_mode_plt_flag of the coding unit that includes the coding block containing the sample p0 is equal to 1.When nDq is greater than 0 and one or more of the following conditions are true, nDq is set equal to 0:        cu_transquant_bypass_flag of the coding unit that includes the coding block containing the sample q0 is equal to 1.        pred_mode_plt_flag of the coding unit that includes the coding block containing the sample q0 is equal to 220.127.116.11.6.7 Filtering Process for a Luma Sample Using Long FiltersInputs to this process are:        the variables maxFilterLengthP and maxFilterLengthQ,        the sample values pi and qj with i=0 . . . maxFilterLengthP and j=0 . . . maxFilterLengthQ,        the locations of pi and qj, (xPi, yPi) and (xQj, yQj) with i=0 . . . maxFilterLengthP−1 and j=0 . . . maxFilterLengthQ−1,        a variable tC.Outputs of this process are:        the filtered sample values pi′ and qj′ with i=0 . . . maxFilterLengthP−1, j=0 . . . maxFilterLenghtQ−1.The variable refMiddle is derived as follows:        If maxFilterLengthP is equal to maxFilterLengthQ and maxFilterLengthP is equal to 5, the following applies:refMiddle=(p4+p3+2*(p2+p1+p0+q0+q1+q2)+q3+q4+8)>>4  (8-1176)        Otherwise, if maxFilterLengthP is equal to maxFilterLengthQ and maxFilterLengthP is not equal to 5, the following applies:refMiddle=(p6+p5+p4+p3+p2+p1+2*(p0+q0)+q1+q2+q3+q4+q5+q6+8)>>4  (8-1177)        Otherwise, if one of the following conditions are true,                    maxFilterLengthQ is equal to 7 and maxFilterLengthP is equal to 5,            maxFilterLengthQ is equal to 5 and maxFilterLengthP is equal to 7,                        the following applies:refMiddle=(p4+p3+2*(p2+p1+p0+q0+q1+q2)+q3+q4+8)>>4  (8-1178)        Otherwise, if one of the following conditions are true,                    maxFilterLengthQ is equal to 5 and maxFilterLengthP is equal to 3,            maxFilterLengthQ is equal to 3 and maxFilterLengthP is equal to 5,                        the following applies:refMiddle=(p3+p2+p1+p0+q0+q1+q2+q3+4)>>3  (8-1179)        Otherwise, if maxFilterLengthQ is equal to 7 and maxFilterLengthP is equal to 3, the following applies:refMiddle=(2*(p2+p1+p0+q0)+p0+p1+q1+q2+q3+q4+q5+q6+8)>>4  (8-1180)        Otherwise, the following applies:refMiddle=(p6+p5+p4+p3+p2+p1+2*(q2+q1+q0+p0)+q0+q1+8)>>4  (8-1181)The variables refP and refQ are derived as follows:refP=(pmaxFilterLengthP+pmaxFilterLengthP−1+1)>>1  (8-1182)refQ=(qmaxFilterLengthQ+qmaxFilterLengthQ−1+1)>>1  (8-1183)The variables fi and tcPDi are defined as follows:        If maxFilterLengthP is equal to 7, the following applies:f0 . . . 6={59,50,41,32,23,14,5}  (8-1184)tCPD0 . . . 6={6,5,4,3,2,1,1}  (8-1185)        Otherwise, if maxFilterLengthP is equal to 5, the following applies:f0 . . . 4={58,45,32,19,6}  (8-1186)tCPD0 . . . 4={6,5,4,3,2}  (8-1187)        Otherwise, the following applies:f0 . . . 2={53,32,11}  (8-1188)tCPD0 . . . 2={6,4,2}  (8-1189)The variables gj and tCQDj are defined as follows:        If maxFilterLengthQ is equal to 7, the following applies:g0 . . . 6={59,50,41,32,23,14,5}  (8-1190)tCQD0 . . . 6={6,5,4,3,2,1,1}  (8-1191)        Otherwise, if maxFilterLengthQ is equal to 5, the following applies:g0 . . . 4={58,45,32,19,6}  (8-1192)tCQD0 . . . 4{=6,5,4,3,2}  (8-1193)        Otherwise, the following applies:g0 . . . 2={53,32,11}  (8-1194)tCQD0 . . . 2={6,4,2}  (8-1195)The filtered sample values pi′ and qi′ with i=0 . . . maxFilterLengthP−1 and j=0 . . . maxFilterLengthQ−1 are derived as follows:pi′=Clip3(pi−(tC*tCPDi)>>1,pi+(tC*tCPDi)>>1,(refMiddle*fi+refP*(64−fi)+32)>>6)  (8-1196)qj′=Clip3(qj−(tC*tCQDj)>>1,qj+(tC*tCQDj)>>1,(refMiddle*gj+refQ*(64−gj)+32)>>6)   (8-1197)When one or more of the following conditions are true, the filtered sample value, pi′ is substituted by the corresponding input sample value pi with i=0 . . . maxFilterLengthP−1:        cu_transquant_bypass_flag of the coding unit that includes the coding block containing the sample pi is equal to 1.        pred_mode_plt_flag of the coding unit that includes the coding block containing the sample pi is equal to 1.When one or more of the following conditions are true, the filtered sample value, qi′ is substituted by the corresponding input sample value qj with j=0 . . . maxFilterLengthQ−1:        cu_transquant_bypass_flag of the coding unit that includes the coding block containing the sample qi is equal to 1.        pred_mode_plt_flag of the coding unit that includes the coding block containing the sample qi is equal to 1.
End Excerpt

Deblocking filter selection in video or image coding


A sealed display device comprises a case for encasing a meter such as a speedometer, tachometer, odometer and the like, viewable through a display window or opening formed in the case, with a transparent cover sealed over the opening. The case has an annular lip surrounding the opening and adapted to receive a peripheral edge of the transparent cover. A layer of sealant is placed between the lip and the cover to seal the cover to the case. A plurality of spaced support members support the cover in spaced relationship to the lip so that a sufficiently thick layer of sealant may be placed between the cover and the lip to prevent breakage of the seal due to differences in thermal expansion and contraction between the case and cover. Angled areas may be milled from the case in surrounding relationship to the lip to define areas for accommodating a thicker layer of sealant than could otherwise be accommodated.

Motorcycles, for example, are equipped with sealed meters or display devices such as tachometers, speedometers, odometers and trip odometers. These meters are sealed by a transparent member such as transparent glass or resin serving to keep water and dirt from getting inside the unit. FIG. 7 shows a seal configuration of this type of display window. Transparent member 103 is set via sealant material 104 into the lip 102 which is formed in the display window unit 101 of the case 100.
In the above-described unit, the transparent member 103 is tightly sealed in the display window 101 around the lip 102 of the display window 101 by means of sealant 104. However, because the assembly of these units requires that the edge of the transparent member 103 be positioned on the top surface of the lip 102 and that it be coated with sealant, it is impossible to use a sufficiently thick layer of sealant 104 and at the same time accurately position the transparent member 103 with respect to the lip.
Accordingly, when the sealed display device is exposed to heat, the differences in the thermal expansion coefficients between the case 100 and the transparent member 103 can cause the seal of the sealant 104 to be broken between the upper surface of the lip 102 and the transparent member 103.
It would be possible to resolve this problem of seal breakage by increasing the thickness of the sealant, but since this would involve broadening the gap between the transparent member and the lip, this would make positioning during assembly all the more difficult and detract from assembly productivity.
There is thus need for a means for covering the opening of an instrument such as a speedometer, tachometer and the like with a transparent member so that the transparent member is sealed to the housing of the instrument with a sufficiently thick layer of sealant to maintain a seal over a prolonged period of time, and which also facilitates production of the sealed unit.

Sealed meter assembly such as for a speedometer, tachometer, odometer or the like


A transistor outline package with integrated thermoelectric cooler is disclosed. The thermoelectric cooler is arranged on a heatsink which extends vertically into the housing of the transistor outline package.

1. Field of the Invention
The invention relates to a transistor outline (TO) package which comprises a mounting space for an electronic component, in particular a hermetically-sealed housing for a laser diode.
2. Description of Related Art
Transistor outline packages, which are used for transceivers in a high-speed computer and telecommunication networks, are known.
In particular, the 10 Gigabit Small Form Factor Pluggable (XPF) is the dominating standard for high-speed networks. Such transceivers comprise a housing with electrical feedthroughs. Inside the housing there is an electronic component comprising a laser diode or photodiode which is coupled with the optical network.
A standard XPF transceiver does not have any integrated cooling capacity. Therefore, XPF transceivers require an external heatsink to ensure sufficient heat dissipation during normal operation.
In addition, the material and process to manufacture XFP headers are costly and complicated.
The document KR 1824922 B shows a transistor outline package which comprises an integrated thermoelectric cooler. The cooler is arranged on the inner surface of the base of the transistor outline package. Since the chip with a laser diode is arranged parallel to the inner surface of the base, a mirror is necessary to reflect the light to the window. In addition, the RF pins have to run along adjacent to the thermoelectric cooler which might result in losses.
The document US 2012/0051382 shows a thermoelectric cooler which is arranged on the base of the header resulting in similar disadvantages as described above.
Accordingly, it is an object of the invention to provide a compact, efficient transistor outline package which comprises an integrated thermoelectric cooler.


Alkenyl or alkyl succinimide additives which are the reaction product of a high molecular weight alkenyl- or alkyl-substituted succinic anhydride and a polyalkylene polyamine having an average of greater than 4 nitrogen atoms per mole, wherein the reaction product is post-treated with a cyclic carbonate, are compatible with fluorocarbon engine seals and, for concentration levels at which fluorocarbon seal compatibility is achieved, possess improved dispersancy and/or detergency properties when employed in lubricating oils and fuels,

1. Field of the Invention
This invention relates to additives which are compatible with fluorocarbon seals and are useful as dispersants and/or detergents in lubricating oils. In particular, this invention is directed toward modified polyamino alkenyl or alkyl succinimides which are the reaction product of an alkenyl- or alkyl-substituted succinic anhydride and a polyalkylene polyamine, wherein the reaction product is post-treated with a cyclic carbonate. The modified polyamino alkenyl or alkyl succinimides of this invention have been found to be compatible with fluorocarbon seals and, for concentration levels at which fluorocarbon seal compatibility is achieved, to possess improved dispersancy and/or detergency properties when employed in a lubricating oil. These modified succinimides are also useful as detergents and/or dispersants in fuels.
2. Prior Art
It is known in the art that alkenyl- or alkyl-substituted succinic anhydrides have been used as dispersants and/or detergents in lubricating oils and fuels. Such alkenyl- or alkyl-substituted succinic anhydrides have been prepared by three well-known processes: a thermal process (see, e.g., U.S. Pat. No. 3,361,673), a chlorination process (see, e.g., U.S. Pat. No. 3,172,892) and a combination of the thermal and chlorination processes (see, e.g., U.S. Pat. No. 3,912,764). The polyisobutenyl succinic anhydride ("PIBSA") produced by the thermal process has been characterized as a monomer containing a double bond in the product. Although the exact structure of chlorination PIBSA has not been definitively determined, the chlorination process PIBSA materials have been characterized as monomers containing either a double bond, a ring other than succinic anhydride ring and/or chlorine in the product. [(See J. Weill and B. Sillion, "Reaction of Chlorinated Polyisobutene with Maleic Anhydride: Mechanism Catalysis by Dichloramaleic Anhydride", Revue de l'Institut Francais du Petrole, Vol. 40, No. 1, pp. 77-89 (January-February, 1985).] Such compositions include one-to-one monomeric adducts (see, e.g., U.S. Pat. Nos. 3,219,666; 3,381,022) as well as "multiply adducted" products, adducts having alkenyl-derived substituents adducted with at least 1.3 succinic groups per alkenyl-derived substituent (see, e.g., U.S. Pat. No. 4,234,435).
Alkenyl or alkyl succinimides formed by the reaction of an alkenyl- or alkyl-substituted succinic anhydride and a polyamine are also well known as lubricating oil dispersant and/or detergent additives. See, e.g., U.S. Pat. Nos. 3,361,673 and 3,018,250.
As taught in U.S. Pat. No. 4,612,132 ("the '132 patent"), alkenyl or alkyl succinimides may be modified such that one or more of the nitrogens of the polyamine moiety is substituted with a hydrocarbyl oxycarbonyl, a hydroxyhydrocarbyl oxycarbonyl or a hydroxy poly(oxyalkylene) oxycarbonyl. These modified succinimides, which impart improved dispersancy and/or detergency properties when employed in lubricating oils, are obtained by reacting the product of an alkyl or alkenyl succinic anhydride and a polyamine with a cyclic carbonate, a linear mono- or poly carbonate, or a chloroformate. The '132 patent discloses succinimide alkenyl or alkyl groups containing from 10 to 300 carbon atoms; most preferred are alkenyl or alkyl groups having from 20 to 100 carbon atoms. However, the highest molecular weight alkenyl or alkyl group specifically taught in the Examples has a molecular weight of 1300. Furthermore, the '132 patent fails to teach anything about the fluorocarbon seal compatibility of the modified succinimides it discloses.
U.S. Pat. No. 4,747,965 discloses modified succinimides similar to those disclosed in the '132 patent, except that the modified succinimides disclosed in this patent are derived from succinimides having an average of greater than 1.0 succinic groups per alkenyl-derived substituent.
While it is known in the art that succinimide additives useful in controlling engine sludge and varnish may be substituted with alkenyl or alkyl groups ranging in number average molecular weight ("Mn") from approximately 300 to 5000, no reference teaches that substituents having a Mn of 2000-2700 perform better than those having a Mn of about 1300. Two references which discuss the effect of the alkenyl-derived substituent's molecular weight on the performance of succinimides as lubricating oil additives are "The Mechanism of Action of Polyisobutenyl Succinimide Lubricating Oil Additives," by E. S. Forbes and E. L. Neustadter (Tribology, Vol. 5, No. 2, pp. 72-77 (April, 1972)), and U.S. Pat. No. 4,234,435 ("the '435 patent").
The Forbes and Neustadter article discusses, in part, the effect of polyisobutenyl Mn on the detergency properties of a polyisobutenyl succinimide. However, as shown in FIG. 1 on page 76 of their article, the results of the tests Forbes and Neustadter conducted indicate that succinimides having a 1300 Mn polyisobutenyl substituent are more effective as detergents than those having a polyisobutenyl substituent with a Mn of 2000 or greater. In showing the effect of polyisobutenyl molecular weight on succinimide detergency, this article teaches that maximum detergency performance is obtained when the polyisobutenyl group has a Mn of about 1300.
The '435 patent teaches a preferred polyalkene-derived substituent group with a Mn in the range of 1500-3200. For polybutenes, an especially preferred Mn range is 1700-2400. However, the '435 patent also teaches that the succinimides must have a succinic ratio of at least 1.3, that is at least 1.3 succinic groups per equivalent weight of polyalkene-derived substituent group. Most preferred are succinimides having a succinic ratio of 1.5-2.5. The '435 patent teaches that succinimides must have have both a high Mn polyalkylene-derived substituent and a high succinic ratio.
The succinimide additives disclosed in the '435 patent are not only dispersants and/or detergents, but also viscosity index improvers. That is, the '435 additives impart fluidity modifying properties to lubricant compositions containing them. However, viscosity index improving properties are not always desirable for the succinimide, as in the case of single-grade oil formulations, for example.
Polyamino alkenyl or alkyl succinimides and other additives useful as dispersants and/or detergents, such as Mannich bases, contain basic nitrogen. While basicity is an important property to have in the dispersant/detergent additive, it is believed that the initial attack on fluorocarbon elastomer seals used in some engines involves attack by the basic nitrogen. This attack leads to the loss of fluoride ions, and eventually results in cracks in the seals and loss of other desirable physical properties in the elastomer.
One approach towards solving the elastomer problem is described in U.S. Pat. No. 4,873,009 to Ronald L. Anderson. This patent is also concerned, in part, with the use of succinimides as lube oil additives. Anderson recognizes in Col. 2, lines 28 et seq. that lube additives prepared from "long chain aliphatic polyamines", i.e., succinimides, "are excellent lube oil additives." Anderson teaches such succinimides are "inferior to additives where the alkylene polyamine is hydroxyalkylated" (Col. 2, lines 31-32). Such hydroxyalkylated polyamine-based succinimides, however, "have the drawback that they tend to attack engine seals particularly those of the fluorocarbon polymer type"(Col. 2, lines 35-37).
Anderson solves his fluorocarbon polymer seal compatibility problem by directly borating his hydroxyalkylated polyamine based succinimides. Furthermore, according to Anderson, it would be desirable for the additive to have a relatively high concentration of N-hydroxyalkyl moieties because the more N-hydroxyalkyl substituents, the cleaner the engine. However, Anderson also teaches that the more amino groups in the polyamine, the greater the degradation of fluorocarbon seal, and that alkylene amines containing more than 2 amino groups cannot be utilized (Col. 2, lines 50-62).
Accordingly, there exists a need in the art for a succinimide lubricating oil additive which is effective in controlling engine sludge and varnish, but which does not require boration to achieve fluorocarbon seal compatibility.

Modified high molecular weight succinimides

Chevron Research and Technology Company, a Division of Chevron U.S.A. Inc.


There is provided an antenna having a spiral-shaped loading formed on the ground plane, in which a resonant frequency is lowered as the reactance component of a CRLH-TL structure is adjusted.

A meta material structure attracting attention recently in the electromagnetic wave application field shows a peculiar phenomenon that has not been mentioned in the general electromagnetic theory. Since the meta material structure has symbols of diverse group velocities and phase velocities in the dispersion characteristic, propagation of electromagnetic waves is explained in the left-hand propagation law, not in the right-hand propagation law. For example, when an electromagnetic wave propagates through a meta material in a free space, the transverse components of a transmitted wave are reverse to those of an incident wave, and if a right-handed transmission line (RH-TL) is combined with a left-handed transmission line (LH-TL), pass and stop bands are formed to be different from those of only a conventional RH-TL.


A method for automatically cutting off power in case of a low battery voltage in a mobile electronic unit is provided. The method comprises (a) cutting off the power of the mobile electronic unit when a battery voltage is detected in a first check section during a booting period of the mobile electronic unit that is not in a normal state, and (b) cutting off the power of the mobile electronic unit when the battery voltage detected with respect to the first check section is in the normal state and when a battery voltage is detected in a second check section during a period after booting of the mobile electronic unit is completed that is not in the normal state.

A digital camera, which is a type of mobile electronic unit, works on a fundamentally different concept than an existing film-type camera. The digital camera photographs a subject through an optical lens system and stores the corresponding photographed image information as digital data in a memory card. The digital data stored in the memory card can be processed in a desired format using a computer and can be easily transmitted via a network. Thus, the demand for digital cameras is expected to substantially increase.
The digital camera operates using power supplied from an AC adapter or a battery. A primary battery, such as an alkaline or lithium, and a secondary battery, such as a lithium-ion (Li-ion) or lithium hydrogen, have been widely used. A nominal voltage and an internal capacity of the secondary battery are higher than those of the primary battery, and thus, the secondary battery can guarantee a more stable operation in case of a low battery voltage. However, if the digital camera uses a current higher than a standard consumption current, such as during a flash check after Iris, shutter 1, and shutter 2 in a low battery voltage, the primary battery does not withstand the load. (In a camera with a two-stage shutter release, the shutter 1 mode operates by an ON signal of a first switch in a two-stage shutter release button for use in performing the camera's AE/AF operations and the shutter 2 mode operates by an ON signal of a second switch in the two-stage button arrangement.) Thus, the operating stability of a variety of IC (integrated circuit) units, such as a digital signal processing unit and a microcontroller of the digital camera, cannot be guaranteed, and communication errors between the IC units occur. In order to prevent the digital camera from malfunctioning, the power should be cut off when low battery voltage is present.

Method of automatically cutting off power in case of low battery voltage in mobile electronic unit


The present invention relates to a decoupler with free wheel system and comprising a vibration damping pulley, a shaft actionable by the pulley, hub pieces having a first hub piece and a second hub piece, hub pieces being mounted between the inner race of the pulley and the outer surface of the shaft, at least one journal element between the shaft and pulley, along with a torsion spring, and a clutch spring, with the first hub piece being mounted on the shaft and the second hub piece being mounted around the shaft and can rotate relative to it, the torsion spring being disposed between the outer race of the hub pieces and the inner race of pulley, having a first end operatively attachable to the pulley and a second end operatively attachable to the second hub piece and the clutch spring being disposed internally in relation to the torsion spring and which is frictionally engaged with the hub pieces for transmission of torque to the shaft.

Overrunning alternator decouplers (OADs) with a free wheel system are used in some types of drive connections such as electrical alternators in automotive vehicles, among others, to enable the transmission of power from a drive shaft to a driven shaft, so that the driven shaft can rotate at a faster speed than the drive shaft or in a different direction of rotation. In these situations, the decoupler allows overrunning between the driving shaft and the driven shaft, providing a free wheel system which allows the two shafts to rotate independently of each other. Furthermore, the decoupler also allows to change the natural resonance frequency of the accessory belt system of an internal combustion engine, reducing noise and vibration of the system as a whole and increasing the useful life of some critical components such as the belt tensioner.
In some torque transmission couplings using a pulley driven by a belt to transmit torque to a shaft, a clutch spring or wrap spring is disposed inside the pulley, in direct contact with the pulley inner race. The axle hub or the driven shaft is arranged internally to the clutch spring, so that the clutch spring performs the torque transmission function. In any event, a friction contact between the clutch spring and the inner surface of the pulley is required so that the driving shaft is coupled to the driven shaft. This friction involves high levels of compression and may cause great wear on the components of the clutch, and in particular on the pulley. To support the high stress levels and to provide acceptable durability of the system, the pulley, and especially its inner race, must be made of a very resistant material, such as steel, and has to be preferably submitted to a heat treatment to increase its strength. These requirements increase the weight and cost of the decoupler, and require more complex production processes.
In addition, the decoupler mechanism should comprise a torsion spring or other equivalent means which can substantially alter the natural resonant frequency (as previously mentioned), and thus ensure improved power transmission performance. Typically, this spring is disposed inside the clutch spring, between it and the shaft or axle hub. To provide the vibrational damping effect, the torsion spring need not exert a contact friction with the other components of the decoupler. However, the larger is the spring, the greater is its strength for the required level of torque for the application. However, the dimensions of the torsion spring are limited by the reduced internal space of the clutch spring.
The document WO2012061936, for example, describes a decoupler which is positionable between an axis (for example, for an alternator shaft), and a power transmission element (for example, an accessory drive belt) on an engine. The decoupler includes an axle hub that is mounted in the pulley, engaging the power transmission member and a spring that provides isolation between the hub and the shaft. The decoupler provides damping at a preset value between the hub and the pulley. This document shows the clutch spring in contact with the track on the inside surface of the pulley to provide frictional engagement, and the torsion spring disposed internally to the spring clutch, providing vibration damping.
The document WO2012061930, for example, refers to a decoupler assembly for use between an axis and an element used to drive the shaft. The decoupler includes a pulley, a hub and a coil torsion spring. The two ends of the spring are engageable, at least indirectly, to the pulley and the hub for the transfer of torque therebetween. At least one end of the spring engages an engagement structure (on either the pulley or the hub) that includes a helical axial shoulder and a driver wall. The spring transfers torque in one direction through the driver wall (for example, when the pulley rotates faster than the hub), but the end of the spring is not fixedly attached to the driver wall. This invention does not allow simultaneous freewheel and anti-vibration damping, nor can any other invention be found in the state of the art showing these two features together, while also using a pulley body of lightweight material.
Another drawback found in the state of the art of decouplers, such as the previous documents mentioned here, is the occurrence of leakage of the grease used to lubricate the clutch spring, torsion spring and other parts, due to centrifugal force generated when the decoupler is in operation. As can be seen in the decouplers of the prior art documents cited here, the axle hub or the bearings are usually in direct contact with the inner race of the pulley, precisely in the region in which the grease is thrown by centrifugal force. This contact zone between the axle hub and pulley is not completely leakage-free Seals may be used to reduce leakage between these parts, but the incorporation of seals means an additional component to the decoupler assembly, which increases the complexity of construction and its cost. In addition, the springs are not completely isolated within the interior of the decoupler housing, which also contributes to the leakage of grease.
In addition, there are no examples in the prior art of an OAD with a fail-safe design which would enable the decoupler to continue to operate for a period of time, in the case of failure or breakage of the torsion spring. In all examples of previous decouplers, when the torsion spring breaks, the pulley loses all function, failing to transmit torque to the driven shaft. If the application of the decoupler is on an automotive alternator, the vehicle will only operate until the battery runs out, and then the vehicle will stop completely due to battery discharge because the alternator is no longer providing electrical energy.
Fail-safe mechanisms would allow the decoupler to continue to operate as if it was a rigid pulley, at least for a period of time, until the damaged pulley can be replaced. Finally, the decoupler with an integral free wheel system can operate as freewheel system only, such as one-way clutches (one-way clutch—OWC) without a vibration absorber system by means of a simple system adaptation.

Decoupler with one-way clutch and fail-safe system


The invention provides an exposure head including:                a light emitting unit;        an imaging unit that allows light from the light emitting unit to enter through an incidence plane and exit from an exit surface so as to form an image at a predetermined position; and        a transparent layer provided between the light emitting unit and the imaging unit, while contacting each of the light emitting unit and the imaging unit;        the transparent layer having a thickness such that an optical distance between the light emitting unit and the incidence plane of the imaging unit becomes a working distance of the imaging unit.

1. Technical Field
The present invention relates to an exposure head and a producing method thereof, a cartridge, and an image forming apparatus.
2. Related Art
For example, in an exposure device of an electrophotographic device and the like, an exposure head having a light emitting device as a light source has been studied.

Exposure head and producing method thereof, cartridge, and image forming apparatus