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WO1994018663A1 - Dispositif de communication par image - Google Patents

Dispositif de communication par image Download PDF

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Publication number
WO1994018663A1
WO1994018663A1 PCT/US1994/001095 US9401095W WO9418663A1 WO 1994018663 A1 WO1994018663 A1 WO 1994018663A1 US 9401095 W US9401095 W US 9401095W WO 9418663 A1 WO9418663 A1 WO 9418663A1
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WO
WIPO (PCT)
Prior art keywords
hand
imaging
communication
individual
sensing
Prior art date
Application number
PCT/US1994/001095
Other languages
English (en)
Inventor
Ehud Baron
Alexander Prishvin
Original Assignee
Wolfe, Edward, A.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Wolfe, Edward, A. filed Critical Wolfe, Edward, A.
Priority to AU61309/94A priority Critical patent/AU6130994A/en
Priority to JP6518135A priority patent/JPH08508354A/ja
Priority to EP94907930A priority patent/EP0681725A4/fr
Publication of WO1994018663A1 publication Critical patent/WO1994018663A1/fr

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Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/033—Pointing devices displaced or positioned by the user, e.g. mice, trackballs, pens or joysticks; Accessories therefor
    • G06F3/0354—Pointing devices displaced or positioned by the user, e.g. mice, trackballs, pens or joysticks; Accessories therefor with detection of 2D relative movements between the device, or an operating part thereof, and a plane or surface, e.g. 2D mice, trackballs, pens or pucks
    • G06F3/03545—Pens or stylus
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/033—Pointing devices displaced or positioned by the user, e.g. mice, trackballs, pens or joysticks; Accessories therefor
    • G06F3/0346—Pointing devices displaced or positioned by the user, e.g. mice, trackballs, pens or joysticks; Accessories therefor with detection of the device orientation or free movement in a 3D space, e.g. 3D mice, 6-DOF [six degrees of freedom] pointers using gyroscopes, accelerometers or tilt-sensors
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V30/00—Character recognition; Recognising digital ink; Document-oriented image-based pattern recognition
    • G06V30/10—Character recognition
    • G06V30/32—Digital ink
    • G06V30/333—Preprocessing; Feature extraction
    • G—PHYSICS
    • G07—CHECKING-DEVICES
    • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
    • G07C9/00—Individual registration on entry or exit
    • G07C9/30—Individual registration on entry or exit not involving the use of a pass
    • G07C9/32—Individual registration on entry or exit not involving the use of a pass in combination with an identity check
    • G07C9/35—Individual registration on entry or exit not involving the use of a pass in combination with an identity check by means of a handwritten signature

Definitions

  • the present invention relates to handwriting and drawing communication devices generally.
  • handwriting analysis is currently employed for two distinct applications identity verification and input of handwritten letters and numbers into a computer. These two applications have sharply contrasting operational requirements and goals.
  • Handwriting analysis for identity verification senses features of handwriting which are distinct for each individual and thus can be used to unambiguously identify a given individual.
  • handwriting analysis for alphanumeric input to a computer seeks to minimize the effect of the very features which are important for identity verification and to concentrate on universal handwriting characteristics which can be associated with given symbols independently of the individual writer.
  • Signature verification systems attempt to identify biometric characteristics of the writer and employ indications such as pressure and acceleration during writing.
  • U.S. Patent 4,345,239 employs pen acceleration for use in a signature verification system.
  • U.S. Patent 5,054,088 employs both acceleration and pressure data characteristics of handwriting for identity verification.
  • pen acceleration is employed for signature verification because it is a personal feature, characteristic of each individual. Accordingly, pen acceleration has not been employed for communication of hand imaging.
  • U.S. Patent 4,817,034 describes a computerized handwriting duplication system employing a digitizer pad.
  • U.S. Patent 4,641,354 describes apparatus for recognizing and displaying handwritten characters and figures in which unrecognized stroke information remains on the display screen.
  • U.S. Patent 4,715,102 describes a process and apparatus involving pattern recognition.
  • U.S. Patent 4,727,588 describes a system for automatic adjustment and editing of a handwritten text image, which preserves format information in a handwritten text.
  • U.S. Patent 4,703,511 describes a writing input and dynamics regeneration device wherein a time dependent code is embedded in a writing path.
  • the present invention seeks to provide improved handwriting and drawing communication apparatus.
  • hand imaging will be used throughout the specification and claims to denote handwriting activity as well as drawing activity and any other two or three dimensional image generating hand movements.
  • communication apparatus for hand imaging including apparatus for sensing features of hand imaging of an individual which features are highly characteristic of the individual but which also contain information relating to images represented thereby and apparatus for providing a non- individual dependent output indicating the images in response to the sensed features.
  • non-individual dependent output denotes an output which contains non-individual characteristics as well as, optionally, individual characteristics.
  • Non-individual characteristics may include a geometric representation of a hand imaging product.
  • the non-individual dependent output is typically in a form that can be communicated and read universally, for example, by any device which is capable of reading data in a standard format.
  • the apparatus for sensing is contained in a hand-held housing.
  • the apparatus for sensing includes apparatus for communication of the non-individual dependent output.
  • the apparatus for communication is operative to communicate information which can be used to reconstruct an individual's hand imaging style.
  • the apparatus for sensing does not require a tablet. Alternatively it may include a tablet. Additionally in accordance with a preferred embodiment of the invention, the apparatus for acquiring and encoding communicates via a modem.
  • the communication may be in a fax format or alternatively in a compressed non-raster format.
  • the communication is wireless communication.
  • communication apparatus for hand imaging including apparatus for sensing features of hand imaging of an individual which features are highly characteristic of the individual but which also contain information relating to images represented thereby, and apparatus for providing a non- individual dependent output indicating the images in response to the sensed features.
  • the apparatus for sensing features is contained in a hand-held housing.
  • the apparatus for sensing features is contained in a tablet assembly.
  • the communication apparatus also includes apparatus for communication of the non-individual dependent output.
  • the communication apparatus also includes apparatus for communication of the non-individual dependent output.
  • the communication apparatus also includes apparatus for communication of the non-individual dependent output.
  • the communication apparatus is operative to communicate information which can be used to reconstruct an individual's hand imaging style.
  • the sensing apparatus does not require a tablet.
  • the apparatus for communication includes a modem.
  • the apparatus for communication is operative to communicate in a fax format.
  • the apparatus for communication is operative to communicate in a compressed non-raster format.
  • the apparatus for communication is operative for wire communication.
  • the apparatus for communication is operative for wireless communication.
  • the apparatus for sensing features includes apparatus for sensing the instantaneous angle of motion during hand imaging.
  • the apparatus for providing a non-individual dependent output is operative for providing an output indication of strokes generated during hand imaging.
  • communication apparatus for hand imaging including apparatus for sensing features of hand imaging of an individual which features are highly characteristic of the individual but which also contain information relating to images represented thereby, and apparatus for providing an output indicating the images in response to the sensed features, and wherein the apparatus for sensing features including apparatus for sensing the instantaneous angle of motion during hand imaging and providing an output indication of strokes generated thereby.
  • apparatus for communicating hand imaging including hand-held apparatus for sensing motion and providing an output in a compressed form which can be transmitted by a conventional modem, LAN or other communications medium.
  • the apparatus includes apparatus for receiving communicated stroke content information and being operative for reconstructing therefrom hand-imaging information.
  • the apparatus for receiving is operative to reconstruct hand-imaging information in three dimensions.
  • communication apparatus for hand imaging including apparatus for sensing motion during hand imaging and providing an output indication of stroke content in a compressed format, and apparatus for receiving communicated stroke content information and being operative to reconstruct therefrom hand-imaging information.
  • the apparatus for receiving is operative to reconstruct hand-imaging information in three dimensions.
  • a communication method for hand imaging including sensing features of hand imaging of an individual which features are highly characteristic of the individual but which also contain information relating to images represented thereby, and providing a non-individual dependent output indicating the images in response to the sensed features.
  • a communication method for hand imaging including sensing features of hand imaging of an individual which features are highly characteristic of the individual but which also contain information relating to images represented thereby, and providing an output indicating the images in response to the sensed features, and wherein the sensing features includes sensing the instantaneous angle of motion during hand imaging and providing an output indication of strokes generated thereby.
  • a method for communicating hand imaging including hand-held apparatus for sensing motion and providing an output in a compressed form which can be transmitted by a conventional modem, LAN or other communications medium.
  • a communication method for hand imaging including sensing motion during hand imaging and providing an output indication of stroke content in a compressed format, and receiving communicated stroke content information and reconstructing therefrom hand-imaging information.
  • Fig. 1 is a pictorial illustration of a device for acquiring and encoding hand imaging which is constructed and operative in accordance with a preferred embodiment of the present invention in an operative environment;
  • FIG. 2 is a simplified illustration of a preferred structure of the acquiring and encoding device of Fig. 1;
  • Fig. 3 is a pictorial illustration of another device for acquiring and encoding hand imaging which is constructed and operative in accordance with a preferred embodiment of the present invention in an operative environment;
  • Fig. 4 is a simplified illustration of a preferred structure of the acquiring and encoding device of Fig. 3;
  • Figs. 5A and 5B are pictorial illustrations of a pocket held communicator unit and pen incorporating the apparatus of Figs. 1 and 2;
  • Fig. 6 is a simplified illustration of apparatus for communicating and reconstructing three-dimensional hand imaging information in accordance with a preferred embodiment of the present invention.
  • Appendix A is a detailed exposition of the findings of the inventor concerning the characterization of hand imaging via pen strokes
  • Appendix B is a computer listing comprising a preferred implementation of a portion of the programming of microcontroller 26;
  • Appendix C is an explanation of the computer listing of appendix B;
  • Appendix D is a computer listing comprising a preferred implementation of a portion of the programming of microcontroller 46;
  • Appendix E is an explanation of the computer listing of appendix D;
  • Appendix F is a computer listing comprising a preferred implementation of a portion of the programming of computer 13;
  • Appendix G is an explanation of the computer listing of appendix F;
  • Appendix H is a computer listing comprising a preferred implementation of a portion of the programming of computer 13;
  • Appendix I is an explanation of the computer listing of appendix H.
  • Fig. 1 illustrates a pen for communicating hand imaging 10 constructed and operative in accordance with a preferred embodiment of the invention in a typical operating environment wherein it communicates by wireless communication with a communicator 11, such as a telephone or RF modem having an associated receiver, such as a model RB 1023 RF receiver, commercially available from RF Monolithics, Inc. of Dallas, Texas.
  • a communicator 11 such as a telephone or RF modem having an associated receiver, such as a model RB 1023 RF receiver, commercially available from RF Monolithics, Inc. of Dallas, Texas.
  • communication may be effected via any other suitable communications medium such as, for example, a local area network and a cellular telephone network.
  • the hand imaging communicating pen 10 which is illustrated in greater detail in Fig. 2, may be used on any writing surface or alternatively in the absence of a writing surface and does not require any special pad or writing substrate.
  • the handwriting input device comprises a housing 12 in the general size and shape of an ordinary pen.
  • Communicator 11 may communicate via telephone or coaxial cabling or wireless facilities with any suitable receiver, such as a computer terminal 13 having an associated printer 14.
  • any suitable receiver such as a computer terminal 13 having an associated printer 14.
  • the hand imaging produced by the user using apparatus 10 may appear nearly instantaneously on a printed hard copy or a computer screen at a remote location.
  • the same general type of apparatus may be employed for display on a television screen or for output on a facsimile receiver.
  • an ink reservoir and output point assembly 16 which may be constructed and operative in any conventional manner. Alternatively no ink output may be provided.
  • an accelerometer 20 disposed in a forward location of the housing 12 an accelerometer 20, preferably operative in three dimensions.
  • a typical accelerometer which meets the size and power requirements of the invention comprises three mutually orthogonally mounted Model 3031-002 accelerometers commercially available from EuroSensor of 20 - 24 Kirby Street, London, England. Alternatively, more than 3 Model 3031-002 accelerometers may be used.
  • the output of the accelerometer 20 is supplied via an operational amplifier 24, such as a model LT1179, commercially available from Linear Technology Corporation of Milpitas, California, to a microcontroller 26, such as an Hitachi H8/536 microcontroller including an A/D converter.
  • Microcontroller 26 is operative to extract a plurality of predetermined features of the acceleration sensed by accelerometer 20. It is a particular feature of the present invention that a relatively small number of discrete features derived from sensed acceleration during hand imaging has been found to be sufficient to map the alphanumeric symbols and graphic output of a given individual. It is appreciated that the characteristics of such features vary from individual to individual and it is often desirable to communicate these personal characteristics. Accordingly, the microcontroller 26 is programmed in order to preserve and communicate not only the information content but also the personal hand imaging characteristics of the writer.
  • Appendix B A preferred listing in the C programming language of software that provides the functionality of the microcontroller 26 appears in Appendix B.
  • Appendix C A brief discussion of the principles underlying the functionality of the microcontroller 26 as exemplified in the software of Appendix B, appears in Appendix C.
  • the microprocessor 26 is operative to extract a plurality of strokes and to encode them in a conventional universal code, such as ASCII, which is not in any way dependent on the personal handwriting characteristics of a given individual and which can be readily accepted by conventional computers, modems and the like.
  • the coded symbol output from microcontroller 26 is in a form compatible with or identical to the output conventionally received from or modem input to a conventional computer, such as a PC.
  • the coded output of microcontroller 26 is transmitted to communicator 11 in a wireless manner by a wireless transmitter 32, such as a model MB1003, which is also commercially available from RF Monolithics, Inc. and which communicates with receiver 12 (Fig 1).
  • a wireless transmitter 32 such as a model MB1003 which is also commercially available from RF Monolithics, Inc. and which communicates with receiver 12 (Fig 1).
  • any other suitable IR transmitter or radio transmitter may be utilized.
  • a non-wireless communication connection may be provided as described hereinbelow with reference to Figs. 5A and 5B.
  • a non-volatile memory such as a flash RAM 34 is preferably provided to store the output of the microcontroller 26.
  • a suitable battery 33 is provided to power the apparatus located within housing 12.
  • the apparatus of the present invention is preferably a hand-held "pen" which can be carried by a user and used with any suitable communication facilities.
  • the communication facilities and computers as well as peripherals communicating therewith need not be personalized in any way, inasmuch as all of the handwriting recognition hardware and software is resident in the "pen”.
  • Figs. 3 and 4 illustrates an alternative embodiment of the present invention which employs a tablet assembly 40 instead of pen 10.
  • the tablet assembly 40 may comprise any conventional graphic input tablet 42, such as a Summagraphics compatible tablet which operates together with a dedicated pen 44 and which outputs x,y coordinates and pen lift signals to a microcontroller 46.
  • Microcontroller 46 may have all of the relevant functionality of microcontroller 26 described hereinabove for stroke extraction and encoding and may communicate directly with a modem/fax unit 48, such as is commercially available from Rockwell and other suppliers.
  • a modem/fax unit 48 such as is commercially available from Rockwell and other suppliers.
  • a preferred listing in the C programming language of software that provides the functionality of the microcontroller 46 appears in Appendix D.
  • Appendix E A brief discussion of the principles underlying the functionality of the microcontroller 46 as exemplified in the software of Appendix D, appears in Appendix E.
  • modem/fax unit 48 may be connected to an ordinary telephone or network jack 50 for communication in the manner described hereinabove in connection with Fig. 1.
  • Appendix F sets forth a software listing in the C programming language for reconstruction functionality of the information communicated by the tablet assembly 40. This software may be resident in computer 13 or alternatively in any output device whose function it is to provide a useful output from the communicated hand imaging information. Appendix G is a brief discussion of the principles underlying reconstruction functionality embodied in the listing of Appendix F.
  • Appendix H sets forth a software listing in the C programming language for reconstruction functionality of the information communicated by the pen 10. This software may be resident in computer 13 or alternatively in any output device whose function it is to provide a useful output from the communicated hand imaging information. Appendix I is a brief discussion of the principles underlying reconstruction functionality embodied in the listing of Appendix H.
  • portable information storage and retrieval apparatus including a portable computer memory and output device and having as an input element hand-held apparatus of the type described hereinabove.
  • a communicator 100 is formed with a socket 101 for removably accepting acquisition and encoding apparatus 102.
  • Data communication contacts 104 and 106 are disposed respectively at an end of the apparatus 102 and in socket 101 for permitting downloading of written information from apparatus 102 to the communicator 100.
  • the communicator is designed to be pocket sized.
  • FIG. 6 illustrates the use of the apparatus of the invention for communicating three dimensional information.
  • a user employing the apparatus outlines the shape of a three dimensional object, such as an airplane model. The user may follow the lines of an existing three dimensional model, as in the illustration, or alternatively, may draw in a free hand manner.
  • the hand imaging produced by the user is communicated via communicator 11 to a communicator 120 and thence to utilization apparatus such as a CNC machine 122 or a three dimensional model building machine 124, such as is commercially available from Cubital Ltd. of Ramat Hasharon, Israel.
  • Communication of hand imaging information in accordance with the present invention may be in two different modes. Where compression is desired along the communication channels, the hand imaging information may be transferred in a penstroke language. In such a case, a hand imaging reconstructor is required at the remote location. Alternatively, the hand imaging information can be reconstructed upstream of communicator 11, by suitable reconstruction apparatus. In such a case, the hand imaging information may be communicated in conventional CAD format.
  • the biological plausibility of an hand writing model involves two parts: The plausibility of the assumed neurological control, and the biomechanical properties of the hand.
  • the preservation of the writing style while using different muscles and even organs, is one of the most interesting questions.
  • the automaticity of writing suggests a chunking mechanism, but this chunking mechanism is probably not in the motoric system of the hand, but somewhere in the upper control levels of the brain. Therefore, whenever we refer to the "hand” , we do it metaphorically. I.e. the " hand” represents the efferent mechanism that accomplishes the motoric control. Recently. Alexander et al.
  • Georgopolos [1] recorded electrical activity of single neurons, and found command neurons in the monkey's motor cortex (precentral gyrus) that encode the direction of forelimb movement. The firing of these neurons was not associated with the contraction of a particular muscle or with the force of the coordinate movement. Georgopoulos computed a vector by summing the firing frequencies of many neurons, and found that it is more correlated with the direction of movement than is the activity of any individual cell. The vector becomes evident several milliseconds before the arm moves. He interpreted this result as evidence for motor neuron planing. Damasio and Damasio [4] discussed the linguistic behavior of patients with lesion in the left posterior temporal and inferior parietal cortex.
  • connectionist view of schemas is that stored knowledgeatoms are dynamically assembled at the time of inference, into contextsensitive schemata.
  • Rumelhart and McClelland (1986) [14] proposed a technique that suggests how an attentional selective mechanism might work. They propose the use of a set of mapping units which produce "dynamically programmable connections" and achieve focusing on different features on different times.
  • Smolensky ( 1986) maintains that schemata are coherent assemblies of knowledge atoms, where coherence or consistency is formalized under the name of harmony. He proposes the harmony principle: the cognitive system is activating coherent assemblies of atoms, and draws inferences that are consistent with the knowledge represented by the activated atoms.
  • Rumelhart [13] developed a system which learns to recognize cursive script as it is generated by a writer. This system learns from examples of cursive script produced by a number of writers and recorded. He collected approximately 1000 words from each of 58 writers. The average length of a word is about 8 characters. That sums up to nearly 500,000 examples of handwritten cursive characters. His results were encouraging and had been used in this research. While Rumelhart [13] was mainly interested in handwriting recognition, this article uses the same data to investigate the writing mechanism.
  • the data were collected in the following manner. Each word in the corpus was recorded. It was then played to the writer who was instructed to write the word on a tablet digitizer. The resulting x coordinate, y coordinate and an indication of whether the pen was or was not on the paper were sampled each 10 milliseconds. The resolution ( more than 200 dpi) and the sampling rate (100 samples/ sec) are those that are shown to be appropriate in the on-line hand-writing recognition literature ([16] ). The data was saved as files, and has been used for the analysis reported in this article.
  • Hiragana characters has the curved shapes of English hand printed characters. but without the ligature of cursive handwriting.
  • a pen stroke was defined as a segments of the cursive writing signal, between two consecutive zero crossing of the vertical velocity of the pen movement. Each character was segmented to several segments or "penstrokes" .
  • a typical writing rate in English is two letters per second.
  • Writing Japanese characters (Hiragana) takes about the same time, and a typical Hiragana character can be written in 0.3 - 0.5 seconds.
  • the principle of segmentation and feature extraction is to segment the continuous signals into discrete segments and to represent each segment by a feature vector in the feature space.
  • a pen-stroke is defined, there are many ways to represent it in a feature space.
  • the on-line character recognition research employs several orthogonal transformations such as a discrete Fourier transform of the curve segments corresponding to the pen-strokes. That is. a pen-stroke is represented by its Fourier coefficients obtained from its x(t) and y(t) signals.
  • any orthogonal transformation e.g. Walsh transform, Karhunen- Loeve
  • Plane curves can be approximated by orthogonal functions (Sinusoidal, polynomial or even square waves). This description can be also easily converted to the frequency domain, as was done in several studies of hand- writing recognition [16].
  • segmentation and feature extraction methods depend of course, on the goal. If the goal is pattern recognition, then the segmentation and feature extraction are geared toward discrimination between the various patterns. In our case, we looked for a segmentation and features that are biological plausible. Consequently, we investigated only features that might be explained by the neurobiological control structures, like the direction of the strokes, their curvature etc.
  • the segmentation and feature extraction mechanism employed was, to develop a model of the underlying handwriting process and to describe the data in terms of the parameters of the model.
  • the model employed was derived from that of Hollerbach [10] and involved the assumption that the generation process could be described as pair of coupled oscillators.
  • the coupled harmonic oscillators is just one of the many models that exist. Actually, its basic assumption about the symmetric shape of the velocity profile (an half sinus shape), is probably an oversimplification.
  • the literature about velocity profiles of pen-strokes usually assumes an asymetrical bell-shaped velocity profile. That is, a rapid-aimed movement described by a log-normal velocity profile is considered as the fundamental unit (stroke). More complex movements are described in terms of superimposed log-normal curves.
  • the asymmetric nature of the velocity bell-shaped profile results from the global stochastic behavior of a large number of processes involved in velocity control.
  • the y -axis consists of a series of up/down strokes whose velocity profile is assumed to be sinusoidal.
  • the x-axis is also pendular with a constant velocity, c, to the right.
  • Different characters are made by modulating the relative amplitudes, a and 6, the relative phase, phi. and the relative frequency w x and w y , in the x and y directions. It is, furthermore assumed that the parameters change only when the velocity in the y direction reaches zero (end of pen-stroke).
  • a stroke as the motion between zero crossings in the y velocity - v y .
  • segmentation occurs when the pen-state changes (from pen-down to pen-up or vice versa).
  • Hollerbach's model was designed for synthesizing handwritten-like character, by a second order mechanical system. This model does not try to imitate the human motor control, or to be used for analysis of human handwriting. However, as it is a control system model, some of the parameters might be interpreted in terms of the human biomechanical system. For example, the parameter ⁇ , which designates the phase shift, can be interpreted as relating to the delay in the nervous-muscular control system. As such, it can have an important diagnostic value in motor diseases.
  • Figure 2 The v x graph for the handwritten letter d written character, to the corresponding velocities. Examples of the handwritten letter d, the corresponding velocity profiles and the reconstructed d are shown in Figures 1,2,3 and 4.
  • the Kanji characters on the other hand, have more short straight segments, as can be seen in the following figures:
  • the "mori” Kanji character in the picture is segmented to 27 pen-strokes (the last two pen-down strokes in the third "tree" are missing). Sixteen out of the twenty seven, are strokes in which the pen touched the paper, and 11 were just for moving the pen from one line to the other. Twelve sequences of "pen-down" strokes, correspond to the visible line segments in the character.
  • FIG. 7 The reconstructed Kanji character: "mori”. The reconstructed Kanji character is depicted in the figure.
  • the basic units of clustering were the pen-strokes, each of which was represented as a point in an n dimensional space. Out of the six features that we extracted for each stroke only three have been used. First, we used only one frequency for the modeling, so the rare strokes that involved .higher harmonies were removed. Second, we did not differentiated between Up-strokes and Down-strokes. Up strokes contain more high order harmonies, but we limited our analysis to the basic movements, and tried to ignore the fluctuation induced by the bio-mechanical control mechanism. The third feature that wasn't used was the mid-point. For the reconstruction of the pen-strokes in the spatial domain, the x-coordinate of the midpoint in each stroke was computed. However, our preliminary analysis showed that this variable was very highly correlated with the x variable. This preliminary analysis, yielded three variables that were almost uncorrelated: ⁇ x , ⁇ y and velocity. The dimension of the space were:
  • the clustering employed a two phase strategy. First, a fast "nearest centroid sorting" algorithm was employed to reveal the clusters in the large data set. Then, the resulting centroids of the clusters have been submitted to different hierarchical clustering methods. The first phase algorithm was
  • Figure 8 Clustering of 25,000 strokes of the same writer. Gray clusters represent down strokes.
  • Figure 9 Thirteen centroid pen-strokes of ah individual writer, including their relative frequencies. sensitive to outlier strokes, that formed separate clusters. This was the reason why we got many very small clusters. These clusters accounted for less than 10 of the observations. They were considered to be noise, or very exeptional pen strokes, and have been removed so not to influence the representativeness of the centroids of the large clusters.
  • the second phase included clustering of the resulting centroids using ten different methods. We distinguished between methods that yield compact hyperspherical clusters, and those that can detect elongate clusters. We start with the first group of eight clustering methods:
  • the different methods tend to favor different characteristics such as size, shape or dispersion.
  • methods based on the least-squares criterion such as k-means or Ward's minimum variance method, tend to find clusters with roughly the same number of observations in each cluster. Average linkage is biased toward finding clusters of equal variance.
  • the clustering methods which are based on nonparametric density estimation, like the single linkage, will be discussed later in this chapter.
  • Figure 10 Hierarchical (compact) clustering of the 12 pen-strokes centroids of a particular writer the above method revealed the following tree-based partition of the set of the basic twelve pen-strokes (of a particular writer).
  • the horizontal-left strokes are one such a group
  • long down strokes are another group.
  • the horizontal strokes themselves are subdivided to horizontal-left directed strokes, and horizontal right and up directed strokes.
  • the high velocity C shaped strokes are part of circles or ovals. It should be noticed that for a specific writer, a certain stroke is always accomplished in the same way. For example, an horizontal short stroke, like crossing a t, will be done always as left directed strokes. Someone else could use only horizontal right directed strokes for that purpose. However, it is very unlikely that the same writer will use both an horizontal-left and horizontal-right strokes. The same is true with long vertical strokes. Once the writer is using a long vertical down-stroke, he will produce vertical lines always as down strokes of the same type and velocity profile. This organization of pen strokes was consistent in all the hierarchical
  • Figure 11 Hierarchical (Density linkage) clustering of the 12 pen-strokes of the same writer clustering algorithms that we mentioned above.
  • the clustering methods that employ nonparametric density estimation can detect also elongated cluster shapes. These clustering techniques yielded two distinct super clusters: the “down and long pen-strokes” , and the “up and right strokes".
  • the down strokes are those that form the "back-bone” of the English characters, while the up-right strokes are typically those that are used as ligature.
  • POD Pen-strokes Ordering Diagram
  • Figure 12 The centroids of the pen strokes of a writer, for English cursive writing.
  • the pen-strokes are ordered according to their v y values, from upstrokes to down strokes
  • Figure 13 The centroids of the pen strokes of a Japanese writer, for Japanese Hiragana characters.
  • the pen-strokes are ordered according to their v y values, from up-strokes to down strokes
  • Figure 14 The centroids of the pen strokes of a Japanese writer, for english characters.
  • the pen-strokes are ordered according to their vy values, from up-strokes to down strokes
  • the pen-stroke is controlled by a direction and amplitude cells, that activate the corresponding primitive motoric patterns (PMPs).
  • PMPs primitive motoric patterns
  • the next stage will be to locate the cell regions that are responsible for this activation in the motor areas of the human brain.
  • MRI Magnetic Resonance Imaging
  • Input array of accel. POS_ST and index of point indl .
  • static float b[5] ⁇ .000416599,.001666397,.002499595,.001666397,.000416599 ⁇ ; static float y[4][5],x[4][5];
  • h_cnt (h_cnt+1 ) % del
  • the procedure performs segmentation of the signals and calculation of each segment's features */
  • the microcontroller gets as inputs the signals of the accelerometers, performs segmentation of it in time (listing of the segmentation program is in appendix B) and represent each segment by several parameters which are transmitted to the receiver.
  • the segmentation of each signal is performed by the movement of the center of oscillations and amplitude and frequency of the oscillations.
  • the procedure of segmentation and feature's extraction consists of the next steps:
  • the first signal is obtained by filtering the acceleration signal from an accelerometer using Butterworth digital filter as described in Digital Filter Design, T.W.Parks and C.S. Burrus, John Wiley & Sons, 1987, chapter 7, section 7.3.3, with 4'th order and 0.02 cutoff frequency.
  • the second signal is obtained by filtering of the differential signal of two accelerometers in a pair, using the Butterworth filter with 4'th order and 0.1 cutoff frequency.
  • int init_com ( int , unsigned ) ;
  • size_file ftell ( fp1 ) ;
  • arr_x1 [j-i] (f loat)p_x [j] ;
  • arr_y1 [j-i] (float)p_y [j] ;
  • arr_y1 [ j] arr_y1 [i] ;
  • arr_x1 [ j ] arr_x1 [i] ;
  • arr_y1 [ j ] arr_y1 [i] ;
  • arr_x1 [j] arr_x1 [i] ;
  • arr_x1 [j] arr_x1 [i] ;
  • arr_yl [j] arr_y1 [i] ;
  • arr_x1 [j] arr_x1 [i] ;
  • v_x [0] [j] (arr_x1 [i+2] -arr_x1 [i + 1] ) ;
  • v_x[1] [j] (arr_x1 [i+1] -arr_x1 [i] ) ;
  • al1 al2/al1
  • vx1 v_x [1] [m+1] ;
  • vy1 v_y [1] [m+1] ;
  • al2 (-dly*vx1+dlx*vy1)
  • strk.x (unsigned) extrxy [0] [m];
  • strk.y (unsigned) extrxy [1] [m];
  • strk.alf1 (signed) (al1*1023.0/5.0);
  • strk.alf2 (signed) (al2*1023.0/5.0);
  • strk.x (unsigned) extrxy [0] [m];
  • strk.y (unsigned) extrxy [1] [m];
  • strk.alf1 0 ;
  • strk.alf2 0 ;
  • fp1 fopen (arg_str [2], "a") ;
  • strcpy (ch, arg_str [2]);
  • fp1 fopen (arg_str [2], "r");
  • size_file ftell ( fp1 ) ;
  • oyx-Intrinsic (Local) coordinate system describing the pen stroke.
  • registerfarbgifont (sansserif_font_far);
  • i fscanf (ff, "%d ⁇ n", &temp);
  • i fread (&temp, sizeof (j), 1, ff);
  • v_x[0] [i] ( (float) vx*5.0/1023.0) ;
  • v_x[l] [i] ( (float) vy*5.0/1023.0) ;
  • y spl (0.0, 0.0, mods, 0.0, al2, al1, mods-x) ;
  • y0 (-bets*x-betc*y+ (float) extrxy [1] [m] ) ;
  • dx (float) (x0-x1) ;
  • Threshold conditions (margin conditions) :
  • a spl ine is defined in the form of

Landscapes

  • Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Human Computer Interaction (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Multimedia (AREA)
  • Character Discrimination (AREA)
  • Television Systems (AREA)
  • Collating Specific Patterns (AREA)
  • Facsimiles In General (AREA)

Abstract

Dispositif de communication servant à former manuellement des images et comprenant un appareil (11) servant à détecter des caractéristiques de formation manuelle d'image (10) d'un individu, lesdites caractéristiques étant extrêmement représentatives dudit individu, mais contenant également des informations relatives aux images représentées, ainsi qu'un appareil (13) servant à créer une sortie (14) non dépendante de l'individu et indiquant les images en réponse aux caractéristiques détectées.
PCT/US1994/001095 1993-02-01 1994-01-31 Dispositif de communication par image WO1994018663A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
AU61309/94A AU6130994A (en) 1993-02-01 1994-01-31 Image communication apparatus
JP6518135A JPH08508354A (ja) 1993-02-01 1994-01-31 画像通信装置
EP94907930A EP0681725A4 (fr) 1993-02-01 1994-01-31 Dispositif de communication par image.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IL10457593A IL104575A (en) 1993-02-01 1993-02-01 Image communication apparatus
IL104575 1993-02-01

Publications (1)

Publication Number Publication Date
WO1994018663A1 true WO1994018663A1 (fr) 1994-08-18

Family

ID=11064475

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1994/001095 WO1994018663A1 (fr) 1993-02-01 1994-01-31 Dispositif de communication par image

Country Status (7)

Country Link
EP (1) EP0681725A4 (fr)
JP (1) JPH08508354A (fr)
CN (1) CN1120868A (fr)
AU (1) AU6130994A (fr)
CA (1) CA2155189A1 (fr)
IL (1) IL104575A (fr)
WO (1) WO1994018663A1 (fr)

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0717367A1 (fr) * 1994-12-16 1996-06-19 Symbios Logic Inc. Crayon à digitaliser et méthode
WO1997019423A1 (fr) * 1995-11-24 1997-05-29 Imax Corporation Systeme et procede de dessin tridimensionnel
US5854634A (en) * 1995-12-26 1998-12-29 Imax Corporation Computer-assisted animation construction system using source poses within a pose transformation space
US5883338A (en) * 1994-12-16 1999-03-16 Hyundai Electronics America, Inc. Telementry by digitizer stylus
GB2329300A (en) * 1997-09-16 1999-03-17 Nokia Mobile Phones Ltd Mobile telephone with handwritten data input
EP0971308A1 (fr) * 1998-07-06 2000-01-12 Thomas Dr. Riedel Dispositif pour l'entrée de données à trois dimensions et procédé de numérisation d'objets
DE19856296A1 (de) * 1998-12-07 2000-06-15 Bosch Gmbh Robert Telekommunikationsendgerät mit Zeichenerkennung
US6081261A (en) * 1995-11-01 2000-06-27 Ricoh Corporation Manual entry interactive paper and electronic document handling and processing system
US6104380A (en) * 1997-04-14 2000-08-15 Ricoh Company, Ltd. Direct pointing apparatus for digital displays
US6181329B1 (en) 1997-12-23 2001-01-30 Ricoh Company, Ltd. Method and apparatus for tracking a hand-held writing instrument with multiple sensors that are calibrated by placing the writing instrument in predetermined positions with respect to the writing surface
US6188392B1 (en) 1997-06-30 2001-02-13 Intel Corporation Electronic pen device
US6201903B1 (en) 1997-09-30 2001-03-13 Ricoh Company, Ltd. Method and apparatus for pen-based faxing
WO2001035329A1 (fr) * 1999-11-08 2001-05-17 Itpen Europe Limited Appareil permettant de numeriser un texte et un dessin a l'aide d'une fonction d'effacement et/ou de pointage
GB2358108A (en) * 1999-11-29 2001-07-11 Nokia Mobile Phones Ltd Controlling a hand-held communication device
WO2001095594A3 (fr) * 2000-06-07 2002-06-27 Siemens Ag Dispositif de communication mobile
US6577299B1 (en) 1998-08-18 2003-06-10 Digital Ink, Inc. Electronic portable pen apparatus and method
WO2004030532A1 (fr) 2002-10-03 2004-04-15 The University Of Queensland Methode et appareil d'evaluation des troubles psychiatriques ou physiques
US6831632B2 (en) 2001-04-09 2004-12-14 I. C. + Technologies Ltd. Apparatus and methods for hand motion tracking and handwriting recognition
WO2005013185A1 (fr) * 2003-07-31 2005-02-10 Jennefer Margaret Tobin Stylo numerique et procede d'utilisation
US7257255B2 (en) 2001-11-21 2007-08-14 Candledragon, Inc. Capturing hand motion
US7268774B2 (en) 1998-08-18 2007-09-11 Candledragon, Inc. Tracking motion of a writing instrument

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5902968A (en) * 1996-02-20 1999-05-11 Ricoh Company, Ltd. Pen-shaped handwriting input apparatus using accelerometers and gyroscopes and an associated operational device for determining pen movement
CN104137026B (zh) * 2011-12-30 2017-05-10 英特尔公司 用于制图识别的方法、装置和系统

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4468694A (en) * 1980-12-30 1984-08-28 International Business Machines Corporation Apparatus and method for remote displaying and sensing of information using shadow parallax
US4806707A (en) * 1988-02-12 1989-02-21 Calcomp Inc. 3-Dimensional digitizer pen
US4856077A (en) * 1986-04-28 1989-08-08 Eric Rothfjell Method of signature verification and device for carrying out the method
US4988981A (en) * 1987-03-17 1991-01-29 Vpl Research, Inc. Computer data entry and manipulation apparatus and method
US5025314A (en) * 1990-07-30 1991-06-18 Xerox Corporation Apparatus allowing remote interactive use of a plurality of writing surfaces
US5164585A (en) * 1991-09-24 1992-11-17 Daniel Y. T. Chen Stylus/digitizer combination with elongate reflectors and linear CCD
US5227622A (en) * 1992-02-06 1993-07-13 Digital Stream Corp. Wireless input system for computer using pen position detection

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59266A (ja) * 1982-06-26 1984-01-05 Fujitsu Ltd 電子黒板装置の色情報入力方式
US4654648A (en) * 1984-12-17 1987-03-31 Herrington Richard A Wireless cursor control system
US4814552A (en) * 1987-12-02 1989-03-21 Xerox Corporation Ultrasound position input device
JP2726594B2 (ja) * 1991-04-01 1998-03-11 八洲電機株式会社 記憶ペン
EP0664912A4 (fr) * 1992-10-13 1996-02-14 Zvi Orbach Appareil de lecture d'une ecriture manuelle.

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4468694A (en) * 1980-12-30 1984-08-28 International Business Machines Corporation Apparatus and method for remote displaying and sensing of information using shadow parallax
US4856077A (en) * 1986-04-28 1989-08-08 Eric Rothfjell Method of signature verification and device for carrying out the method
US4988981A (en) * 1987-03-17 1991-01-29 Vpl Research, Inc. Computer data entry and manipulation apparatus and method
US4988981B1 (en) * 1987-03-17 1999-05-18 Vpl Newco Inc Computer data entry and manipulation apparatus and method
US4806707A (en) * 1988-02-12 1989-02-21 Calcomp Inc. 3-Dimensional digitizer pen
US5025314A (en) * 1990-07-30 1991-06-18 Xerox Corporation Apparatus allowing remote interactive use of a plurality of writing surfaces
US5164585A (en) * 1991-09-24 1992-11-17 Daniel Y. T. Chen Stylus/digitizer combination with elongate reflectors and linear CCD
US5227622A (en) * 1992-02-06 1993-07-13 Digital Stream Corp. Wireless input system for computer using pen position detection

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP0681725A4 *

Cited By (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6556694B2 (en) 1994-12-16 2003-04-29 Hyundai Electronics America Digitizer stylus containing handwriting data
US5883338A (en) * 1994-12-16 1999-03-16 Hyundai Electronics America, Inc. Telementry by digitizer stylus
EP0717367A1 (fr) * 1994-12-16 1996-06-19 Symbios Logic Inc. Crayon à digitaliser et méthode
EP1130536A3 (fr) * 1994-12-16 2001-10-17 Hyundai Electronics America Appareil et procédé avec stylo de numérisation
EP1130536A2 (fr) * 1994-12-16 2001-09-05 Hyundai Electronics America Appareil et procédé avec stylo de numérisation
US6195446B1 (en) 1994-12-16 2001-02-27 Hyundai Electronics America Digitizer stylus with memory for storing handwriting data
US6081261A (en) * 1995-11-01 2000-06-27 Ricoh Corporation Manual entry interactive paper and electronic document handling and processing system
WO1997019423A1 (fr) * 1995-11-24 1997-05-29 Imax Corporation Systeme et procede de dessin tridimensionnel
US5847710A (en) * 1995-11-24 1998-12-08 Imax Corp. Method and apparatus for creating three dimensional drawings
US6373492B1 (en) 1995-12-26 2002-04-16 Imax Corporation Computer-assisted animation construction system and method and user interface
US5854634A (en) * 1995-12-26 1998-12-29 Imax Corporation Computer-assisted animation construction system using source poses within a pose transformation space
US6577315B1 (en) 1995-12-26 2003-06-10 Imax Corporation Computer-assisted animation construction system and method and user interface
US6104380A (en) * 1997-04-14 2000-08-15 Ricoh Company, Ltd. Direct pointing apparatus for digital displays
US6188392B1 (en) 1997-06-30 2001-02-13 Intel Corporation Electronic pen device
GB2329300B (en) * 1997-09-16 2002-07-17 Nokia Mobile Phones Ltd Mobile telephone with handwritten data input
CN1316842C (zh) * 1997-09-16 2007-05-16 诺基亚流动电话有限公司 移动无线电话和对其输入信息的方法和设备
US6487421B2 (en) 1997-09-16 2002-11-26 Nokia Mobile Phones Limited Method for inputting information to a mobile radiotelephone
EP0907278A3 (fr) * 1997-09-16 1999-09-29 Nokia Mobile Phones Ltd. Radiotéléphone mobile
EP0907278A2 (fr) * 1997-09-16 1999-04-07 Nokia Mobile Phones Ltd. Radiotéléphone mobile
GB2329300A (en) * 1997-09-16 1999-03-17 Nokia Mobile Phones Ltd Mobile telephone with handwritten data input
US6201903B1 (en) 1997-09-30 2001-03-13 Ricoh Company, Ltd. Method and apparatus for pen-based faxing
US6492981B1 (en) 1997-12-23 2002-12-10 Ricoh Company, Ltd. Calibration of a system for tracking a writing instrument with multiple sensors
US6181329B1 (en) 1997-12-23 2001-01-30 Ricoh Company, Ltd. Method and apparatus for tracking a hand-held writing instrument with multiple sensors that are calibrated by placing the writing instrument in predetermined positions with respect to the writing surface
EP0971308A1 (fr) * 1998-07-06 2000-01-12 Thomas Dr. Riedel Dispositif pour l'entrée de données à trois dimensions et procédé de numérisation d'objets
US6577299B1 (en) 1998-08-18 2003-06-10 Digital Ink, Inc. Electronic portable pen apparatus and method
US7268774B2 (en) 1998-08-18 2007-09-11 Candledragon, Inc. Tracking motion of a writing instrument
DE19856296B4 (de) * 1998-12-07 2014-01-23 Ipcom Gmbh & Co. Kg Telekommunikationsendgerät mit Zeichenerkennung
DE19856296A1 (de) * 1998-12-07 2000-06-15 Bosch Gmbh Robert Telekommunikationsendgerät mit Zeichenerkennung
WO2001035329A1 (fr) * 1999-11-08 2001-05-17 Itpen Europe Limited Appareil permettant de numeriser un texte et un dessin a l'aide d'une fonction d'effacement et/ou de pointage
GB2358108A (en) * 1999-11-29 2001-07-11 Nokia Mobile Phones Ltd Controlling a hand-held communication device
WO2001095594A3 (fr) * 2000-06-07 2002-06-27 Siemens Ag Dispositif de communication mobile
US6831632B2 (en) 2001-04-09 2004-12-14 I. C. + Technologies Ltd. Apparatus and methods for hand motion tracking and handwriting recognition
US7394460B2 (en) 2001-04-09 2008-07-01 I.C. + Technologies Ltd. Apparatus and method for hand motion tracking and handwriting recognition
US7911457B2 (en) 2001-04-09 2011-03-22 I.C. + Technologies Ltd. Apparatus and methods for hand motion detection and hand motion tracking generally
US8686976B2 (en) 2001-04-09 2014-04-01 I.C. + Technologies Ltd. Apparatus and method for hand motion detection and hand motion tracking generally
US7257255B2 (en) 2001-11-21 2007-08-14 Candledragon, Inc. Capturing hand motion
EP1545302A1 (fr) * 2002-10-03 2005-06-29 Joachim Diederich Methode et appareil d'evaluation des troubles psychiatriques ou physiques
WO2004030532A1 (fr) 2002-10-03 2004-04-15 The University Of Queensland Methode et appareil d'evaluation des troubles psychiatriques ou physiques
EP1545302A4 (fr) * 2002-10-03 2008-12-17 Joachim Diederich Methode et appareil d'evaluation des troubles psychiatriques ou physiques
WO2005013185A1 (fr) * 2003-07-31 2005-02-10 Jennefer Margaret Tobin Stylo numerique et procede d'utilisation

Also Published As

Publication number Publication date
IL104575A0 (en) 1993-06-10
IL104575A (en) 1997-01-10
CA2155189A1 (fr) 1994-08-18
EP0681725A4 (fr) 1998-04-15
JPH08508354A (ja) 1996-09-03
EP0681725A1 (fr) 1995-11-15
CN1120868A (zh) 1996-04-17
AU6130994A (en) 1994-08-29

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