JP2006268494A - Image processing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a person to intuitively and efficiently understand measured velocity vectors. <P>SOLUTION: After measuring velocity vectors of toner particles flying in a minute void formed by a particle carrier 2 and an electrostatic latent image holder 4 by PTV from two image data picked up by a CCD camera 10, an image processing device 12 converts the measured velocity vectors into image information and displays it on the screen of a display device 14. Velocity vectors corresponding to the position of a cursor 34 out of the measured velocity vectors are further converted to generate tactile information, and a presentation part 24 is driven according to the tactile information to present a user with the velocity vectors in the cursor position tactilely. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image processing apparatus that displays on a screen a velocity distribution obtained by imaging powder particles that actually fly in order to investigate the behavior of powder and the like. It relates to the configuration of the device presented in.

  For example, there is PTV (Particle Tracking Velocity) as one method for measuring the velocity of tracer particles flying in a minute gap formed by an image carrier and a developing roll and obtaining a velocity vector of each particle. For example, Patent Document 1 discloses a technique for measuring the velocity vector distribution of toner particles flying in a minute gap formed by an image carrier and a developing roll using this PTV.

In this conventional example, two still images of toner particles flying are obtained by imaging twice in a minute gap formed by an image carrier and a developing roll at predetermined time intervals. Since each still image captures reflected light by light irradiation, the background portion has a low luminance value and the particle image has a high luminance. Thereby, the image can be binarized by setting a threshold value of luminance. This threshold value can be set to an optimum value in consideration of the influence of shooting conditions, etc. In an n-bit image, that is, an image having a density of 2 ⁿ gradations, the (2 ⁿ × 1/4) gradation It is desirable to set between the level and the (2 ⁿ × 3/4) th gradation level. For example, in an 8-bit (256 gradation) image, the range is from the 64th to the 192nd. By binarizing still images in this way, a toner particle image can be extracted from each still image.

  Then, a predetermined calculation is performed, and the velocity and direction of each toner particle can be measured by associating the same toner particle captured with each still image. This measurement result can be confirmed by displaying it on the screen as a velocity vector distribution.

  In particular, this conventional example can accurately extract a velocity vector even when there are variations in the diameters of the particles to be measured for the velocity vector, and an error in association (error vector) is generated in each still image. It can be greatly reduced. However, from experience, the error vector cannot be completely lost.

  As described above, the particle image in the image can be identified from the background portion by the set threshold value. Therefore, in order to further reduce the number of error vectors in the prior art, the speed vector distribution displayed on the screen is visually observed, the threshold value is increased or decreased by experience, a predetermined calculation is performed again, and the speed vector distribution is displayed again. The process was repeated.

  In recent years, in addition to vision, a technique has been proposed in which, for example, it is made audible and presented by hearing or by tactile sensation (for example, Non-Patent Document 1). As a result, the user can intuitively grasp the measurement data or the change state of the measurement data. Further, the present patent applicant has also proposed an interface for presenting information to the user with a tactile sensation (for example, Patent Document 2).

JP 2004-61701 A JP 2000-330688 A [Search on December 13, 2004], Internet <http://www.sensable.com/languages/jp-hp.asp>

  However, since the number of toner particles flying between the image carrier and the developing roll is large, the number of velocity vectors displayed on the screen inevitably increases. As a result, the velocity vector is superimposed and displayed. In other words, since normal speed vectors and error vectors are mixed and displayed in a minute gap formed by the image carrier and the developing roll, it is difficult to detect the presence or absence of error vectors from the screen. . Furthermore, there is a problem that it is difficult to discriminate the vector direction and the scalar.

  In order to eliminate this, it is conceivable to display an enlarged portion of the superimposed display. However, the enlarged display does not change even if the enlarged display is performed. Further, the enlarged display window is usually displayed at a different location from the display window of the minute gap. For this reason, in order to confirm which part of the minute gap is displayed in an enlarged manner, it is necessary to move the line of sight each time, and it is troublesome to associate each display content.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an image processing apparatus capable of intuitively and efficiently grasping a measured velocity vector.

  In order to achieve the object as described above, the image processing apparatus according to the present invention performs the same particle matching process between images obtained by imaging a particle flying in a minute gap a plurality of times. In the image processing apparatus for obtaining the velocity vector of each particle and displaying on the screen, a display control means for displaying the velocity vector on the screen, a position detection means for detecting the position of the pointer that moves on the screen in response to a user operation, A tactile force presenting means for presenting a tactile force sense to a user, and a tactile for driving the tactile force presenting means from a velocity vector of particles that have moved the position of the pointer detected on the screen by the position detecting means. Tactile force information generating means for generating force information, and drive control means for controlling the driving of the tactile force presentation means in accordance with the tactile force information generated by the tactile force information generating means. The features.

  Further, the display control means displays on the screen at least one of a correct vector obtained by successfully matching the same particles among the velocity vectors and an error vector obtained by being unable to associate. It is characterized by doing.

  In addition, the haptic information generating means may include at least one of a correct vector obtained by successfully matching the same particles among the velocity vectors and an error vector obtained without being able to associate. It is characterized by generating tactile sensation information from.

  The display control means displays on the screen a correct vector obtained by successfully matching the same particles among the velocity vectors, and the haptic information generating means includes the velocity vector of the velocity vectors. Generating the tactile sensation information from the error vector obtained without being able to associate the same particles, and presenting the correct vector visually and the error vector haptic sensation respectively. To do.

  According to the present invention, since the velocity vector of the particle can be presented not only by visual display but also by tactile sensation, the state of the velocity vector of the particle can be grasped intuitively and efficiently. In particular, with visual presentation alone, it is difficult to see the status of the error vector because the correct vector and error vector are mixed and displayed, but only the error vector should be presented with a tactile sensation. For example, the user can intuitively understand the situation of the error vector with the sense of touch. In this way, the haptic sensation representing the situation of the error vector can be presented as an index for adjusting the threshold value set for extracting the particle image from the image, thereby reducing the occurrence of the error vector. Such a threshold setting can be effectively and efficiently performed by the user.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is an overall configuration diagram of an image processing system employing an embodiment of an image processing apparatus according to the present invention. FIG. 2 shows an enlarged view of the moving region portion of the toner particles as the subject. This image processing system irradiates a particle flying in a minute gap formed between a pulse generator 6 and two objects with a laser beam for a minute time in synchronization with a pulse output from the pulse generator 6. A laser device 8; a CCD camera 10 that captures a still image of the particles in synchronization with the pulse; and an image processing device 12 that calculates the velocity of the particles from an image signal output from the CCD camera 10; Is used to measure the velocity of toner particles flying in the minute gap formed by the particle carrier 2 corresponding to the developing roll and the electrostatic latent image holding member 4, and measure the velocity vector of each toner particle. It is a system for displaying. In the present embodiment, as a means for presenting the obtained velocity vector distribution, in addition to the display device 14 presented visually, a haptic sense presentation device 16 presented by a haptic sense is provided. It is a feature.

  The laser device 8 uses a light source such as a YAG laser whose light emission time and light emission interval can be adjusted arbitrarily. As shown in FIG. 2, a cylindrical lens 18 is provided as an optical system for diffusing light in a planar shape. ing. The laser device 8 is installed so as to irradiate the region where the particles fly from the upstream side of the process at the position where the particle carrier 2 and the electrostatic latent image holding body 4 face each other. Laser light is output in synchronization with the output pulse. The laser light is diffused in a planar shape by a cylindrical lens 18 and is irradiated in a planar manner on a gap formed between the particle carrier 2 and the electrostatic latent image holder 4. This limits the particles that reflect the light. The bias voltage application device 20 connected to the particle carrier 2 applies a bias voltage to the particle carrier 2 in synchronization with the pulse output from the pulse generator 6.

  The CCD camera 10 is installed so as to capture an image from a direction substantially perpendicular to the planar light emitted by the laser device 8, and the laser device 8 emits the laser light in synchronization with the pulse output from the pulse generator 6. The image is taken almost at the same time.

  Since the still image captured by the CCD camera 10 captures reflected light by light irradiation, the background portion has a low luminance value and the particle image has a high luminance. Thereby, the image processing apparatus 12 binarizes the image by setting a luminance threshold value, and extracts the toner particle image from the still image. Then, a predetermined calculation is performed, and the velocity and direction of each toner particle are measured by associating the same toner particle captured with each still image, and the measured velocity vector is displayed on the display device 14 or later as described in detail later. Presented by the haptic sense presentation device 16.

  The present embodiment can be configured by using the configuration shown in Patent Document 1 as a basic configuration and providing a haptic sense presentation device 16 on the basic configuration.

  FIG. 3 is a block diagram of the image processing apparatus according to the present embodiment. In FIG. 3, the tactile force sense presentation device 16 includes a mouse 22 and a presentation portion 24 that protrudes from the upper surface of the mouse 22. The mouse 22 is an operation means operated by the user to move the cursor 34 on the display screen as is well known. The presentation part 24 is tactile force sense presenting means for presenting the velocity vector at the cursor position on the displayed measurement environment to the user with a tactile force sense through the touched fingertip. The mouse 22 and the presentation site 24 exchange information with components provided in the image processing apparatus 12 via corresponding interfaces (IF) 26 and 28, respectively. Among these, the mouse interface 26 includes a position detection unit 30 that detects the operation direction and amount of the mouse 22 by the user. The display control unit 32 displays the cursor 34 of the mouse 22 on the screen and moves the cursor 34 according to mouse operation information including the operation direction and amount detected by the position detection unit 30.

  The image processing apparatus 12 that forms the main part of the measurement apparatus according to the present embodiment is realized by the same configuration as a general-purpose computer such as a CPU, a memory, and an external storage device, and operates on the computer hardware and the computer. The following components are realized by cooperative operation with application software.

  The image data input unit 36 in the present embodiment inputs image data obtained by being imaged by the CCD camera 10. The velocity vector measurement processing unit 38 obtains the velocity vector of each toner particle imaged using PTV based on the two image data sent from the image data input unit 36. The toner particle image in the still image is extracted from the still image by binarizing the image data on the basis of the set luminance threshold, and the threshold input unit 40 is used to set the threshold. Means. The velocity vector data group obtained by the velocity vector measurement processing unit 38 is output to the image information generation unit 42 and the haptic information generation unit 44. In FIG. 3, the velocity vector is illustrated as being directly output from the velocity vector measurement processing unit 38 to each of the information generation units 42 and 44. However, the velocity vector data group is temporarily stored in a storage unit (not illustrated) and each information You may comprise so that the production | generation parts 42 and 44 may read the velocity vector of presentation object from the memory | storage part. The image information generation unit 42 generates image information by converting the velocity vector into image data that can be visualized. The display control unit 32 displays the image information generated by the image information generation unit 42 on the display unit 14.

  The display unit 14 displays not only the velocity vector, but also the measurement environment, that is, the inside of the minute gap formed by the particle carrier 2 and the electrostatic latent image holder 4 where the toner particle flight is measured. However, the image of the measurement environment may be generated from the image data captured by the CCD camera 10. If the measurement environment is known information, the image information of the measurement environment is registered in the image processing device 12 in advance. You may comprise so that registration information may be displayed.

  The haptic information generating unit 44 generates haptic information by converting the velocity vector generated by the velocity vector measurement processing unit 38. The presentation site interface 28 includes a drive control unit 46 that performs drive control of the presentation site 24 in accordance with the haptic information generated by the haptic information generation unit 44. By the drive control by the drive control unit 46, the presentation site 24 presents the velocity vector at the position of the cursor 34 to the user through the touched fingertip with a tactile force sense. Note that the tactile sensation presentation device 16 in the present embodiment can use the information sensing device disclosed in the above-mentioned Patent Document 2 by the applicant of the present patent application.

  Next, the operation in this embodiment will be described.

  First, the user sets an interval between the particle carrier 2 and the electrostatic latent image holder 4 to an arbitrary value (200 to 600 μm). Then, a bias voltage is applied to the particle carrier 2, and the toner particles are caused to fly by an action force due to an electric field generated between the electrostatic latent image carrier 4. In order to image the toner particles irradiated with laser light among the flying toner particles irradiated with laser light, the cylindrical lens 18 and the CCD camera 10 are adjusted and focused. When shooting flying particles, the phase difference between the application of the bias voltage and the light emission and image acquisition timing of the laser device 8, the light emission time and light emission interval of the laser device 8, and the output value of the laser device 8 are set.

  As described above, after setting each parameter related to the setting of the measurement environment, imaging is performed, the velocity vector of each toner particle is measured, and a process of presenting is started. Hereinafter, the process of presenting the velocity vector of the toner particles in the present embodiment will be described with reference to the flowchart shown in FIG.

  After setting each of the above parameters, the CCD camera 10 takes a picture of the minute gap formed by the particle carrier 2 and the electrostatic latent image holder 4 twice. In order to accurately measure the toner particle speed, it is preferable to vary the light emission interval of the laser device 8 in accordance with the flying speed of the toner particles. Specifically, the light emission interval is shortened when the flying speed of the toner particles is fast, and the light emission interval is lengthened when the speed is slow. An image obtained by observing the toner particles 50 flying from the particle carrier 2 to the electrostatic latent image carrier 4 is schematically shown in FIGS.

  When the image data input unit 36 acquires two still image data captured by the CCD camera 10 (step 110), the speed vector measurement processing unit 38 sets the image data input unit 36 based on the set luminance threshold. Each input still image data is binarized and toner particles captured from the still image are extracted (step 120). Then, by associating the same toner particles picked up with each still image, the velocity and direction of each toner particle are obtained by calculation to obtain a velocity vector (step 130). FIG. 6 schematically shows the velocity vector thus obtained together with the toner particles. In FIG. 6, the velocity vector of toner particles that linearly fly from the particle carrier 2 to the electrostatic latent image carrier 4 is the correct vector 50a, and the other is the error vector 50b.

  In addition, a known technique can be utilized for the processing so far. In the present embodiment, it is assumed that the flying particle velocity measurement method described in Patent Document 1 is used. The presenting method described below is a feature of the present embodiment.

  The image information generation unit 42 generates image information that can be visualized by performing data conversion on the velocity vector obtained by the velocity vector measurement processing unit 38. Then, the display control unit 32 displays the cursor 34 on the screen at the generated velocity vector, the measurement environment including the particle carrier 2 and the electrostatic latent image holding body 4, and the position detected by the position detection unit 30. In this way, the speed vector is presented on the screen so that it can be visualized (step 140). In this process, an image displayed on the display device 14 is as shown in FIG. FIG. 7 is a diagram in which a cursor 34 is added to FIG.

  On the other hand, the haptic information generating unit 44 extracts only the velocity vector of the toner particle that has moved the position indicated by the cursor 34 from the velocity vectors obtained by the velocity vector measurement processing unit 38, and uses the extracted velocity vector as a tactile signal. Tactile force sense information to be presented by force sense is generated. Here, the toner particles moved to the position indicated by the cursor 34 are not only the velocity vector having the position as the start point and the end point, but also the velocity vector having passed the position is to be presented by the sense of touch. The drive control unit 46 drives the presentation site 24 in accordance with the haptic information generated by the haptic information generating unit 44. As a result, the presenting part 24 presents the velocity vector at the position of the cursor 34 to the user through the touched fingertip (step 150).

  For example, a tactile sensation that gives a strong impact if the arrow is a long (large scalar quantity) velocity vector and a weak impact if the arrow is a short (small scalar quantity) velocity vector. Generate haptic information. The direction in which the impact is applied is naturally matched to the direction of the arrow. If there is one toner particle that moves the cursor position, tactile sensation information is generated according to the velocity vector of the toner particle, but if there are a plurality of toner particles, the velocity obtained by summing the velocity vectors of the toner particles. Generate haptic information with vectors.

  Here, the mouse 22 constituting the tactile sensation presentation device 16 is moved by the user, and the cursor 34 is moved between the particle carrier 2 and the electrostatic latent image holder 4 on the screen in accordance with the user operation. (Step 160). Then, the haptic information generating unit 44 extracts the velocity vector of the toner particles corresponding to the moving position of the cursor 34, and generates haptic information based on the extracted velocity vector. Even during movement, the velocity vector at each passing point is presented in real time with a tactile sensation. As a result, the presentation site 24 presents the velocity vector at the current cursor position to the user with a tactile sensation (step 150). If only the correct vector exists, the user has a stable tactile force from only one direction from the particle carrier 2 side (left side) to the electrostatic latent image carrier 4 side (right side) on the screen, although there are strengths. You should be able to feel your senses, but if there is an error vector in the movement path of the cursor, you will feel your sense of force from various directions.

  Thus, in the present embodiment, the velocity vector at the cursor position is presented with a tactile force sense. The display device 14 also displays the same speed vector data on the screen. However, if the number of toner particles is large, the speed vector itself is displayed in a superimposed manner. Therefore, the speed vector, particularly the error vector, especially the length of the arrow is displayed. May not be detected. On the other hand, when the velocity vector is presented by tactile force sense, if there is an error vector, the user feels force sense in the direction other than the left side to the right side as described above. Can be grasped intuitively.

  Therefore, the user moves the cursor vertically and horizontally in the space formed by the particle carrier 2 and the electrostatic latent image holder 4 on the screen, and moves the cursor so as to pass through the space linearly. This makes it possible to intuitively feel all of the measured error vectors with the sense of touch. If it is determined that there are a large number of error vectors, the threshold is reset. This is because in the still image, the background portion and the toner particles are discriminated by binarization using a threshold value. Note that the direction of the error vector can be sensed by the sense of touch, so that the user can determine from experience whether to increase or decrease the threshold from the direction of the error vector.

  When the threshold is reset by the user (step 170), the velocity vector measurement processing unit 38 binarizes each still image data and extracts toner particles based on the reset luminance threshold (step 170). 120). As described above, the velocity vector of each toner particle is presented visually and by tactile sensation (steps 140 and 150), but the configuration of the extracted toner particles is changed by changing the threshold value. Therefore, the extracted velocity vector and the error vector that is configured also change. In this way, the user can reduce the error vector while changing the threshold value.

  According to the present embodiment, as described above, the velocity vector can be presented not only visually but also by tactile sensation, so that the user can intuitively grasp the velocity vector. In particular, even in situations where it is difficult to visually recognize the presence of an error vector due to the superimposed display of the velocity vector, the speed vector at the cursor position can be presented with a tactile sensation. Thus, the error vector can be reduced as described above.

  By the way, in the above description, all the extracted speed vectors have been presented, but the type of speed vector to be presented may be selectable. That is, since the correct vector and the error vector are mixed in the speed vector, the type of the correct vector and the error vector is determined when the speed vector is obtained in the above step 130, and before the presentation in the above steps 140 and 150. The user is allowed to select the type of vector to be presented visually and tactilely. Thereby, for example, a correct vector can be presented visually, and an error vector can be presented by tactile sensation. FIG. 8 shows a screen display example when the erroneous vector is removed and the correct vector is visually presented.

  As described above, if only the erroneous vector is presented by the haptic sense instead of all the extracted velocity vectors, the presence of the erroneous vector can be more intuitively understood.

  In the above description, an example in which the present invention is applied to an image processing system that measures and displays the velocity vector of toner particles flying between the particle carrier 2 and the electrostatic latent image holding body 4 using PTV. Explained. However, it is not necessary to limit to this. For example, it is called PIV (Particle Image Velocity), and analyzes the amount of movement of the luminance pattern (concentration pattern) of a particle group in a limited rectangular area in a particle image within a minute time, thereby analyzing the particle group in the fluid. The present invention can also be applied to a system that measures the amount of movement.

  PIV is suitable for measuring airflow and high-concentration particles. The basic configuration and operation of a system using PIV may be almost the same as that of PTV. In the system using PIV, as indicated by dots in FIG. 9, the tracer particles 52 are injected into a limited rectangular area, and the roller speed of the particle carrier 2 is further adjusted as a parameter setting. In the system using PIV, diagrams corresponding to FIGS. 5, 7, and 8 when PTV is used are shown in FIGS. 9, 10, and 11, respectively.

1 is an overall configuration diagram of an image processing system adopting an embodiment of an image processing apparatus according to the present invention. FIG. 2 is an enlarged view of a moving region portion of toner particles that are a subject in FIG. 1. It is a block block diagram of the image processing apparatus in this Embodiment. 6 is a flowchart showing a velocity vector presentation process of toner particles in the present embodiment. FIG. 5 is a diagram schematically showing an image obtained by observing toner particles flying from a particle carrier to an electrostatic latent image carrier in the present embodiment. FIG. 6 is a diagram schematically showing velocity vectors measured for each toner particle from FIG. 5. It is the figure which showed the example of a screen when displaying the velocity vector shown in FIG. 6 in this Embodiment. It is the figure which showed the example of a display screen when an error vector is removed from FIG. In the image processing system of this Embodiment using PIV, it is the figure which showed typically the image which observed the tracer particle | grains which flow between a particle carrier and an electrostatic latent image holding body. It is the figure which showed the example of a screen when displaying the velocity vector measured from the image shown in FIG. It is the figure which showed the example of a display screen when an error vector is removed from FIG.

Explanation of symbols

  2 particle carrier, 4 electrostatic latent image holder, 6 pulse generator, 8 laser device, 8 display device, 10 camera, 12 image processing device, 14 display device, 16 tactile sensation presentation device, 18 cylindrical lens, 20 Bias voltage application device, 22 mouse, 24 presentation site, 26 mouse interface (IF), 28 presentation site interface (IF), 30 position detection unit, 32 display control unit, 34 cursor, 36 image data input unit, 38 velocity vector measurement Processing unit, 40 threshold input unit, 42 image information generation unit, 44 haptic information generation unit, 46 drive control unit, 50 toner particles, 50a correct vector, 50b error vector, 52 tracer particles.

Claims (4)

In the image processing device that obtains the velocity vector of each particle by performing the matching process of the same particle between the images obtained by imaging the particles flying in the minute gap multiple times,
Display control means for displaying the velocity vector on a screen;
Position detecting means for detecting the position of a pointer that moves on the screen in response to a user operation;
Tactile sensation presentation means for presenting tactile sensation to the user;
Haptic information generating means for generating haptic information for driving the haptic presentation means from the velocity vector of the particle that has moved the position of the pointer detected by the position detecting means on the screen;
Drive control means for performing drive control of the haptic sense presentation means according to the haptic information generated by the haptic information generation means;
An image processing apparatus comprising: The image processing apparatus according to claim 1.
The display control means displays, on the screen, at least one of a correct vector obtained by successfully matching the same particle among the velocity vectors and an error vector obtained without being associated. An image processing apparatus. The image processing apparatus according to claim 1.
The tactile force sense information generating means is configured to detect a touch from at least one of a correct vector obtained by successfully matching the same particle among the velocity vectors and an error vector obtained by being unable to associate. An image processing apparatus that generates haptic information. The image processing apparatus according to claim 1.
The display control means displays a correct vector obtained by successfully matching the same particle among the velocity vectors on the screen,
The haptic information generating means generates haptic information from an error vector obtained without being able to associate the same particle among the velocity vectors,
An image processing apparatus, wherein the correct vector is presented visually, and the error vector is presented hapticly.

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