JP2006126362A - Camera, prediction method and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a predictive AF (Auto-Focus) from performing wrong decisions, even if there are errors in the measured range information, etc., in a camera having a predictive AF means. <P>SOLUTION: In a digital camera 10 which is equipped with a moving body speed predicting function 78A3 and a moving body moving direction predicting function 78A4 which generate predicted information being the range information by predicting the movement of an object, based on the positional information of the object which is range information; and an AF control function 78A1 which performs focusing based on the predictive information; information about the movement of the object is inputted by the vertical direction key of a key matrix 50 and the AF control function 78A1; and the predicted information and the information about the movement of the object which is inputted are compared by the AF control function 78A1. Moreover, when there is a difference between two pieces of information, the moving body speed predicting function 78A3 and the moving body moving direction predicting function 78A4 perform prediction error display on a TFT panel 42. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a camera having a predictive autofocus (AF) function for focusing on a moving subject, and a prediction method in such a camera. The present invention also relates to a program for causing a computer to execute such a prediction method.

  The basic operation of AF is to measure the position to the subject, focus the photographing lens at the measured position, and perform photographing.

  However, when the subject is moving, the subject is out of focus by moving the subject in the time from the distance measurement to the shooting. Therefore, there is known a camera equipped with a moving object prediction AF mode that predicts a position where a subject will move after a predetermined time when the subject is moving and performs a focusing operation on the predicted position. ing.

For example, in Patent Document 1, when it is determined that the subject is a moving object, the focusing lens group is driven at a constant speed at a follow-up speed that matches the moving speed of the subject, and from the time when the release switch is turned on until the start of exposure. An automatic focus detection device that calculates a correction amount for correcting the follow-up speed based on the release time lag is disclosed. In this case, the subject distance measurement uses a phase difference method.
JP-A-6-337345

  The moving object prediction AF is a technique for controlling the focus by performing distance measurement a plurality of times, detecting the relative speed of the subject based on the distance measurement information, and predicting the actual shooting distance. However, if the prediction is wrong due to erroneous detection or the like, there is a drawback that the actually captured image becomes out of focus.

  For example, in the case of phase difference AF in the above-mentioned Patent Document 1, if the number of samplings per distance measurement is increased by the number of times of the phase difference AF, the distance measurement accuracy will be improved. Since the time required for the distance measurement becomes longer and it becomes impossible to flexibly cope with the movement of the subject, it is considered that a focusing error eventually occurs when the movement of the subject changes. On the other hand, development of high-speed AF processing and advanced judgment function algorithms is not easy. Since the moving object prediction AF function is operated and the focus is shifted, the prediction AF becomes meaningless. Therefore, a prediction AF function that does not make an erroneous prediction for a detection error or the like is required.

  The present invention has been made in view of the above points, and is a camera provided with a predictive AF means, in which the predictive AF does not misjudge even if there is an error in measured distance measurement information, etc. An object of the present invention is to provide such a prediction method and program.

The first aspect of the camera of the present invention is:
Prediction means for predicting movement of a subject based on subject position information and generating prediction information;
Focusing means for focusing based on the prediction information generated by the prediction means;
Input means for inputting information relating to the movement of the subject;
A comparison means for comparing the prediction information generated by the prediction means with information relating to the movement of the subject input by the input means;
Comprising
The prediction means performs a prediction error display when the comparison means determines that there is a difference between the two pieces of information.
It is characterized by that.

The second aspect of the camera of the present invention is:
Prediction means for predicting movement of a subject based on subject position information and generating prediction information;
Focusing means for focusing based on the prediction information generated by the prediction means;
Input means for inputting information relating to the movement of the subject;
A comparison means for comparing the prediction information generated by the prediction means with information relating to the movement of the subject input by the input means;
Comprising
The prediction means updates the prediction information based on repeatedly acquired subject position information,
The comparison means compares the new prediction information based on the new subject position information generated by the prediction means and the information related to the movement of the subject input by the input means,
The focusing means performs focusing based on the new prediction information when the comparing means determines that there is no difference between the new prediction information and the input information related to the movement of the subject.
It is characterized by that.

The third aspect of the camera of the present invention is
Prediction means for predicting movement of a subject based on subject position information and generating prediction information;
Focusing means for focusing based on the prediction information generated by the prediction means;
Input means for inputting information relating to the movement of the subject;
A comparison means for comparing the prediction information generated by the prediction means with information relating to the movement of the subject input by the input means;
Comprising
If the focusing means determines that the two pieces of information are different from each other, the focusing means replaces the prediction information generated by the prediction means with respect to the movement of the subject input by the input means. Focusing based on the value of
It is characterized by that.

The fourth aspect of the camera of the present invention is
Prediction focusing means for predicting movement of the subject based on the subject position information, generating prediction information, and focusing based on the generated prediction information;
Input means for inputting information for comparison with the prediction information generated by the prediction focusing means;
A comparison unit that compares the prediction information generated by the prediction focusing unit and the information input by the input unit;
Comprising
The prediction focusing means performs different processing according to the comparison result of the two information by the comparison means.
It is characterized by that.

On the other hand, one aspect of the prediction method of the present invention is:
In a prediction method for generating prediction information by predicting movement of a subject based on subject position information for focusing on a moving subject,
The information regarding the movement of the subject input by the operator is compared with the prediction information, and when there is a difference between the two information, a prediction error process is performed.

One aspect of the program of the present invention is as follows:
A program for causing a computer to execute a prediction method for predicting movement of a subject based on subject position information and generating prediction information for focusing on a moving subject,
In the prediction method, the information on the movement of the subject input by the operator is compared with the prediction information, and when there is a difference between the two information, a prediction error process is performed.
It is characterized by that.

  According to the present invention, there is provided a camera provided with a predictive AF means, in which the predictive AF does not make a misjudgment even if there is an error in the measured distance measurement information or the like, such a predictive method, and a program can do.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

[First Embodiment]
FIG. 1 is a diagram showing a configuration of a digital camera as a camera according to the first embodiment of the present invention.

  That is, in the digital camera 10, the light passing through the lens 12 is exposed by the CCD 14, extracted as an electrical signal by the imaging circuit 16, and converted into digital data by the A / D conversion circuit 18. Then, various corrections necessary for recording such as gamma correction are applied by the correction circuit 20 and then recorded as digital image data (RAW data) in the frame memory 22. The CPU 24 has a frame memory control function 24A, a recording medium access function 24B, an image compression function 24C, and an image expansion function 24D. The CPU 24 temporarily converts the RAW data recorded in the frame memory 22 into YUV data. After that, it is compressed into JPEG data. The JPEG data is stored and recorded in the recording medium 30 via the recording buffer 26 and the recording medium I / F 28.

  Thus, the JPEG data stored and recorded on the recording medium 30 is read from the recording medium 30 via the recording medium I / F 28 and the recording buffer 26 by the CPU 24 and is temporarily written in the frame memory 22. The CPU 24 reads the JPEG data written in the frame memory 22, decompresses it to YUV data, resizes it to a size suitable for display, and stores it in the frame memory 22 again. By writing in the FIFO memory 32, it is supplied to the TFT liquid crystal driving circuit 36 and the video output circuit 38 via the on-screen circuit 34. Here, the on-screen circuit 34 creates display data by superimposing characters, symbols, marks, etc. on an image. The TFT liquid crystal drive circuit 36 displays the supplied display data on the TFT panel 42 illuminated by the backlight unit 40. The video output circuit 38 displays the supplied display data on a television or the like connected to the video output terminal 44 by externally outputting the display data through the video output terminal 44.

  In addition, a so-called monitor image before the release operation is output to the TFT panel 42. This is not the use of all the pixel data of the CCD 16, but the RAW data read out by thinning is temporarily stored in the frame memory 22 and converted into YUV data, and then the size (number of pixels, aspect) of the TFT panel 42 is converted. The data is resized to the FIFO memory 32. By performing this operation, for example, 30 frames per second, the TFT panel 42 can be used as a finder.

  Also, YUV data converted from the RAW data read out by thinning is compressed by a predetermined moving image compression method such as motion JPEG using a plurality of frames, and can be stored and recorded in the recording medium 30 as moving image data. It is.

  The JPEG data recorded on the recording medium 30 is read from the recording medium 30 via the recording medium I / F 28 and the recording buffer 26 by the CPU 24 and temporarily written in the frame memory 22. Then, the JPEG data written in the frame memory 22 is read out, decompressed, stored again in the frame memory 22, and then written in the FIFO memory 32, so that it is displayed on the TFT panel 42, a television, or the like. Can do.

  The LCD panel 46 is a display unit for displaying various information such as the operation mode of the digital camera 10, and the LCD display circuit 48 is a control circuit thereof. The key matrix 50 is an operation member including a release key, a cross key, a mode key, and the like. The external data I / F 52 is an interface for exchanging data with a personal computer (not shown) connected by a USB cable (not shown), and the connection detection means 54 is connected to the external data I / F of the USB cable. It detects the connection.

  The EEPROM (flash ROM) 56 causes the CPU 78 to execute adjustment data of the digital camera 10, control processing of the digital camera, AF control function, passive AF sensor control function, moving body speed prediction function, and moving body movement direction prediction function described later. This is a memory storing a program for the purpose.

  The actuator 58 includes a zoom motor (in the case of a zoom camera), an AF motor, a shutter, a diaphragm, and the like, and the actuator drive circuit 60 is the drive circuit thereof. The lens barrier open / close detection circuit 62 is arranged on the front surface of the lens 12 and detects an open / close state of a barrier (not shown) functioning as a power switch, for example.

  The battery 64 is an AA battery or a lithium ion battery, and the battery state detection circuit 66 detects the state of the battery 64. Based on the detection result of the battery state detection circuit 66, for example, when the battery runs out, a battery remaining amount warning can be issued to the LCD panel 46. The power supply circuit 68 generates power for the entire digital camera 10 based on the battery 64, and the backup power supply 70 is for holding date information and the like.

  The strobe 72 is a flash illumination device for illuminating the subject at the time of shooting, and the strobe driving circuit 74 is a circuit for causing the strobe 72 to emit light. The passive AF sensor 76 measures the distance to the subject and obtains subject position information.

  The CPU 78 provides a system control function 78A for controlling the entire digital camera 10 by reading and executing a program stored in the EEPROM 56. The system control function 78A includes an AF control function 78A1, a passive AF sensor control function 78A2, a moving body speed prediction function 78A3, a moving body movement direction prediction function 78A4, and the like.

  Here, the AF control function 78A1 is a function of controlling the actuator drive circuit 60 and driving the photographing lens 12 to the in-focus state by the actuator 58. In this case, the AF mode includes a normal AF mode and a predictive AF mode.

  The passive AF sensor control function 78A2 is a function for controlling the passive AF sensor 76.

  The moving object speed prediction function 78A3 and the moving object movement direction prediction function 78A4 are based on the object movement speed and the object movement information based on the object position information captured from the passive AF sensor 76 by the passive AF sensor control function 78A2 in the prediction AF mode. It predicts the direction of movement. That is, in the predictive AF mode, the AF control function 78A1 drives the lens 12 in a focused state based on the prediction information predicted by the moving object speed prediction function 78A3 and the moving object movement direction prediction function 78A4. It has become.

  FIG. 2A is an operation flowchart of the AF control function 78A1 in the system control function 78A of the CPU 78 in the present embodiment. That is, when the lens barrier (not shown) of the digital camera 10 is opened and the power is turned on, first, an ON operation of the moving object prediction AF function by a mode key (not shown) of the key matrix 50 is accepted (step S10).

  If the moving object prediction AF function ON operation is not performed (step S30), the process proceeds to step S40 described later.

  On the other hand, when the moving object prediction AF function ON operation is performed (step S20), subject direction / speed input processing is executed (step S30). After that, it is determined whether or not the subject photographing by the release key operation of the key matrix 50 is instructed (step S40). Here, if the subject photographing instruction is not given, the process returns to step S30, and if it is made, the control by the AF control function 78A1 is terminated and the process proceeds to the photographing process.

  FIG. 2B is a flowchart showing details of the subject direction / speed input process executed in step 30. That is, first, an operation (pressing) of the up / down direction key of the cross key, which is a set of operation members arranged symmetrically on the camera housing, is accepted (step S31). And it is discriminate | determined whether such an up-down direction key was operated (step S32).

  If it is determined that the up / down direction key has not been operated, the end of the subject direction / speed input process is determined based on a predetermined condition such as no up / down key operation for a predetermined time (step S33). If completed, the subject direction / speed input process is terminated and the process returns to the upper routine. Thus, in the normal AF mode in which the moving object prediction AF function is not turned on, nothing is performed in the subject direction / speed input process.

  On the other hand, when it is determined that the up / down direction key has been operated (step S32), the operation is opposite to the direction of the subject movement direction input value currently held in the internal memory (not shown) of the CPU 76. It is determined whether or not a direction key indicating a direction has been operated (step S34).

  If it is determined that the direction key in the direction opposite to the current direction is not operated, the subject moving speed input value held in the internal memory (not shown) of the CPU 76 is set as the speed in the current direction. Up (step S35). If it is determined that the direction key opposite to the current direction has been operated, the subject movement direction input value held in the internal memory (not shown) of the CPU 76 is set in the pressed direction (step S36). ).

  Then, the process proceeds to step S33, and if the subject direction / speed input process has not been completed yet, the process returns to step S31 and the above process is repeated.

  With such subject direction / speed input processing, the TFT panel 42 is turned on when the subject movement direction input value and the movement speed input value held in the internal memory (not shown) of the CPU 76 according to the operation of the up / down direction key are updated. The icons displayed on the screen are also updated and displayed to indicate their contents.

  For example, when the up direction key is operated, the input value of the subject movement direction becomes the separating direction and the input value of the subject moving speed becomes 5 km / h. As shown in FIG. 3, the subject moves at a distance of 5 km / h. An icon 101 indicating movement is displayed. When the up direction key is further operated in this state, the subject moving speed input value becomes 10 km / h, and the display is updated to display the icon 102 indicating that the subject moves at 10 km / h in the away direction. When the up direction key is further operated, the subject moving speed input value becomes 15 km / h, and the icon 103 indicating that the subject moves at 15 km / h in the direction of moving away is updated and displayed. On the other hand, for example, when the down arrow key is operated in a state where the icon 102 indicating that the subject moves at 10 km / h in the direction away from the above is displayed, the input value of the subject moving direction approaches the approaching direction. The object moving speed input value is 5 km / h, and the display is changed to the icon 104 indicating that the object moves at 5 km / h in the approaching direction. When the down key is further operated in this state, the subject moving speed input value becomes 10 km / h, and the icon 105 indicating that the subject moves at 10 km / h in the approaching direction is updated and displayed.

  That is, depending on the subject, there are many scenes in which the user can input an approximate speed in advance. For children's athletic events, trains, cars, etc., it seems that the direction and speed of the movement of most subjects can be predicted in advance by the user. Therefore, in this embodiment, the moving speed value and moving direction value of these subjects are input in advance.

  For comparison with the present embodiment, FIG. 4A is an operational flowchart of a photographing operation by the conventional moving object prediction AF when the subject moving speed value and the moving direction value are not input in advance as in the present embodiment. Show. That is, when there is a 1st trigger input by the 1st release key operation (step S1), the subject position information is obtained by the passive AF sensor 76, and the actuator 58 is driven via the actuator drive circuit 60 based on that to align the lens 12. A so-called AF operation for moving to a focal position is executed (step S2). Thereafter, comparison with the previous AF information is performed (step S3), and the moving speed and moving direction of the subject are predicted based on the comparison result (step S4). Thereafter, it is determined whether or not a 2nd trigger is input by operating the 2nd release key (step S5). If there is no input, the process returns to step S2 to repeat the above operation. Thus, if there is a 2nd trigger input (step S5), the object speed and direction based on the prediction are obtained by moving the lens 12 in the movement speed and direction based on the prediction in step S4. The focus is adjusted to (step S6). Then, a photographing operation is performed (step S7), and the process is terminated.

  On the other hand, FIG. 4B shows an operation flowchart of the photographing operation by the moving object prediction AF using the subject movement speed and the advance input of the movement direction in the present embodiment.

  That is, first, in response to the 1st trigger input by the 1st release key operation of the key matrix 50, the variable n held in the memory (not shown) in the CPU 78 is set to “1” and the variable error is set to “0” (step S101). Then, the passive AF sensor control function 78A2 obtains subject position information by the passive AF sensor 76, and based on that, the AF control function 78A1 drives the actuator 58 via the actuator drive circuit 60 to move the lens 12 to the in-focus position. A so-called AF operation is executed (step S102). Thereafter, the moving object moving speed predicting function 78A3 and the moving object moving direction predicting function 78A4 compare with the previous AF information (step S103), and predict the moving speed and moving direction of the subject based on the comparison result (step S103). S104).

  Next, the AF control function 78A1 compares the predicted movement speed and movement direction of the subject with the pre-input values held in the memory (not shown), that is, the subject movement speed value and the movement direction value, and is different. In this case, the variable error is set to “1” and the variable n is set to “1”. If they match, only the variable n is incremented by “+1” (step S105). For example, if the direction is different, the variable error is set to “1”. The variable error is also set to “1” when the speed is shifted by, for example, ± 20% or more even if the directions are the same.

  Thereafter, it is determined whether or not the variable error is “1” (step S106). Here, when the variable error is not “1”, the prediction error display on-screen display on the TFT panel 42 is turned off (step S107). Of course, in this case, if the prediction error display is not performed, this is the same as performing nothing. Then, the value of the variable n is confirmed, and if it is “3” or more, the variable error is set to “0” (step S108). Thereafter, it is determined whether or not there is a 2nd trigger input by operating the 2nd release key of the key matrix 50 (step S109). If there is no input, the process returns to step S102 and the above operation is repeated.

  If it is determined in step S106 that the variable error is “1”, a prediction error display is displayed on the TFT panel 42 on-screen (step S110), and then the process proceeds to step S108. In this way, when there is a difference between the predicted moving speed and moving direction of the subject and the pre-input value, it is possible to warn the photographer of the occurrence of the prediction error by performing the prediction error display.

  In this prediction error display, the variable error is returned to “0” in the next step S108 if the predicted moving speed and moving direction of the subject and the pre-input value match three or more times even after an error has occurred once. Therefore, it is turned off when the process of step S107 is subsequently executed.

  Thus, if there is a 2nd trigger input (step S109), it is confirmed whether or not the variable error is “1” (step S111). The AF control function 78A1 drives the actuator 58 via the actuator drive circuit 60 to move the lens 12 in the moving speed and moving direction of the subject based on the prediction, thereby focusing on the subject speed and direction based on the prediction. Adjust (step S112). Then, a photographing operation is performed (step S113), and the process is terminated.

  Here, the contents of step S112 will be specifically described. Since the time from the last AF information acquisition to the start of exposure is a settable amount or a fixed time, the distance to be corrected can be easily calculated if the predicted moving speed of the subject is known. Therefore, the distance obtained by multiplying the subject distance calculated based on the last AF information by the predicted movement speed of the subject by the time from the acquisition of the AF information to the start of exposure is determined according to the predicted movement direction. Then, the focus lens position is adjusted to the corrected distance. Thereby, it is possible to prevent a focus shift due to a time lag of the moving subject.

  If it is determined in step S111 that the variable error is “1”, step S112 is skipped and the photographing operation in step S113 is performed. That is, imaging is performed without performing the moving object prediction AF.

  As described above, in the first embodiment, it is possible to determine whether or not there is an error in the measured distance measurement information or the like by comparing the predicted moving speed and moving direction of the subject with the pre-input value. As a result, the prediction AF does not make a misjudgment. And when there exists such an error, prediction AF using it is not performed.

  Further, by performing the prediction error display, the photographer can be warned of the occurrence of the prediction error.

[Second Embodiment]
Next, a second embodiment of the present invention will be described.

  In the second embodiment, errors such as measured distance measurement information are corrected only once.

  Therefore, the configuration and operation of the present embodiment are basically the same as those of the first embodiment, and the shooting operation by the moving object prediction AF using the prior input of the subject moving speed and the moving direction is as shown in FIG. It has only changed.

  That is, first, in response to the 1st trigger input by the 1st release key operation of the key matrix 50, the variable n held in the memory (not shown) in the CPU 78 is set to “0” and the variable error is set to “0” (step S201). Then, as in the first embodiment, the AF operation is executed based on the subject position information (step S102), compared with the previous AF information (step S103), and the moving speed and moving direction of the subject are determined. Each is predicted (step S104).

  Next, in the present embodiment, the AF control function 78A1 compares the predicted movement speed and movement direction of the subject with the pre-input values held in the memory (not shown), that is, the subject movement speed value and the movement direction value. If they are different, the variable n is incremented by “+1”, and if they match, both the variables error and n are set to “1” (step S202).

  Thereafter, it is determined whether or not the variable n is “1” or more (step S203). Here, when the variable n is not “1” or more, that is, “0”, the prediction error display to be displayed on the TFT panel 42 is turned off (step S107). Thereafter, it is determined whether or not there is a 2nd trigger input by operating the 2nd release key of the key matrix 50 (step S109). If there is no input, the process returns to step S102 and the above operation is repeated.

  If it is determined in step S203 that the variable n is “1” or more, it is further determined whether or not the variable n is “1” (step S204). Here, when the variable n is “1”, the prediction value predicted in step S104 this time, that is, the moving speed and moving direction of the subject are ignored (step S205). Thereafter, the process proceeds to step S109, and it is determined whether or not there is a 2nd trigger input.

  In this embodiment, the operations in steps S111 to S113 are the same as those in the first embodiment. Therefore, even if there is a 2nd trigger input here, an erroneous prediction value due to an error in the measured distance measurement information or the like. Focus adjustment based on the predicted value up to the previous time is ignored.

  On the other hand, if it is determined in step S204 that the variable n is not “1”, that is, “2” or more, a prediction error display is displayed on the TFT panel 42 and the variable error is set to “1”. (Step S206), the process proceeds to Step S108.

  Therefore, when there is an error twice or more, imaging is performed only with normal AF without performing prediction AF so that prediction AF with an incorrect prediction value is not performed.

  As described above, the second embodiment has the same effects as those of the first embodiment, and further, when an error occurs in the measured distance measurement information due to the influence of noise or the like, Prediction AF using the previous predicted value can be performed without using.

[Third Embodiment]
Next, a third embodiment of the present invention will be described.

  In the third embodiment, when predictive AF based on a predicted value cannot be performed, the predicted AF is performed by supplementing with a pre-input value.

  Therefore, the configuration and operation of this embodiment are basically the same as those of the second embodiment, and the shooting operation by moving object predictive AF using the subject movement speed and the advance input of the movement direction is as shown in FIG. It has only changed.

  That is, in this embodiment, when it is determined in step S111 in the operation of the second embodiment that the variable error is “1”, the prior input value held in the memory (not shown) of the CPU 78, that is, subject movement The focus of the lens 12 is adjusted to the subject speed and direction based on the speed value and the moving direction value (step S301). Then, a photographing operation is performed (step S113), and the process is terminated.

  As described above, in the third embodiment, the same effect as that of the second embodiment is obtained, and further, when an unreliable predicted value is obtained, the pre-input value is used. Even if there is a detection error in distance measurement, it is possible to prevent the occurrence of a large focusing error.

  The first to third embodiments described so far are realized by the control processing of the CPU 78 according to the program. That is, the program itself realizes the functions of the above-described embodiments. This program itself constitutes the present invention.

  These programs may be in the form of a recording medium other than the above-described EEPROM 56, or may be stored in a recording medium that can be attached to and detached from the camera. As a recording medium, in addition to a floppy (registered trademark) disk and a CD-ROM, an optical recording medium such as a DVD, a magnetic recording medium such as an MD, a tape medium, a semiconductor memory such as an IC card, and the like can be used. A recording medium storing this program also constitutes the present invention.

  In addition, a storage device such as a hard disk or a RAM provided in a server system connected to a dedicated communication network or the Internet may be used as a recording medium, and the program may be provided to the camera via the communication network.

  Alternatively, it goes without saying that such a program is included in the embodiment of the present invention even when the functions of the above-described embodiment are realized in cooperation with other application software or the like.

  In the present embodiment, the program is executed by being executed on the CPU. However, the present invention is not limited to this. For example, the program may be realized by hardware.

  Although the present invention has been described above based on the embodiments, the present invention is not limited to the above-described embodiments, and various modifications and applications are naturally possible within the scope of the gist of the present invention.

  For example, in the above embodiment, the moving speed and moving direction of the subject are input using the up / down direction key of the cross key as a set of operation members, but may be input using the left / right direction key. However, other appropriate keys can be assigned.

(Appendix)
The invention having the following configuration can be extracted from the specific embodiment.

(1) Prediction means (moving body speed prediction, moving body movement direction prediction) for predicting movement (speed, direction) of a subject based on subject position information (passive AF) and generating prediction information;
Focusing means for focusing based on the prediction information generated by the prediction means;
Input means for inputting information relating to the movement of the subject;
A comparison means for comparing the prediction information generated by the prediction means with information relating to the movement of the subject input by the input means;
Comprising
The prediction means performs a prediction error display when the comparison means determines that there is a difference between the two pieces of information.
A camera characterized by that.

(Corresponding embodiment)
The embodiment relating to the camera described in (1) corresponds to the first embodiment. In this embodiment, the moving body speed prediction function 78A3 and the moving body movement direction prediction function 78A4 are the prediction means, the AF control function 78A1 is the focusing means, the up / down direction key of the key matrix 50 and the AF control function 78A1 are the input means. Further, the AF control function 78A1 corresponds to the comparison means.

(Function and effect)
According to the camera described in (1), it is possible to determine whether or not there is an error in the subject position information by comparing the prediction information with the information input by the input unit. There is no judgment. In addition, the photographer can be warned of the occurrence of a prediction error.

(2) Prediction means for predicting movement of a subject based on subject position information and generating prediction information;
Focusing means for focusing based on the prediction information generated by the prediction means;
Input means for inputting information relating to the movement of the subject;
A comparison means for comparing the prediction information generated by the prediction means with information relating to the movement of the subject input by the input means;
Comprising
The prediction means updates the prediction information based on repeatedly acquired subject position information,
The comparison means compares the new prediction information based on the new subject position information generated by the prediction means and the information related to the movement of the subject input by the input means,
The focusing means performs focusing based on the new prediction information when the comparing means determines that there is no difference between the new prediction information and the input information related to the movement of the subject.
A camera characterized by that.

(Corresponding embodiment)
The embodiment relating to the camera described in (2) corresponds to the second embodiment. In this embodiment, the moving body speed prediction function 78A3 and the moving body movement direction prediction function 78A4 are the prediction means, the AF control function 78A1 is the focusing means, the up / down direction key of the key matrix 50 and the AF control function 78A1 are the input means. Further, the AF control function 78A1 corresponds to the comparison means.

(Function and effect)
According to the camera described in (2), it is possible to determine whether or not there is an error in the subject position information by comparing the prediction information with the information input by the input unit. There is no judgment. Further, when an error occurs in the subject position information due to the influence of noise or the like, prediction AF using the previous prediction value can be performed without using the error.

(3) Prediction means for predicting movement of a subject based on subject position information and generating prediction information;
Focusing means for focusing based on the prediction information generated by the prediction means;
Input means for inputting information relating to the movement of the subject;
A comparison means for comparing the prediction information generated by the prediction means with information relating to the movement of the subject input by the input means;
Comprising
If the focusing means determines that the two pieces of information are different from each other, the focusing means replaces the prediction information generated by the prediction means with respect to the movement of the subject input by the input means. Focusing based on the value of
A camera characterized by that.

(Corresponding embodiment)
The embodiment relating to the camera described in (3) corresponds to the third embodiment. In this embodiment, the moving body speed prediction function 78A3 and the moving body movement direction prediction function 78A4 are the prediction means, the AF control function 78A1 is the focusing means, the up / down direction key of the key matrix 50 and the AF control function 78A1 are the input means. Further, the AF control function 78A1 corresponds to the comparison means.

(Function and effect)
According to the camera described in (3), it is possible to determine whether or not there is an error in the subject position information by comparing the prediction information with the information input by the input unit. There is no judgment. In addition, even when prediction information with no reliability is obtained, since the input information is used, it is possible to prevent the occurrence of a large focusing error even if there is an error in the subject position information.

(4) Prediction focusing means for predicting movement of the subject based on the subject position information, generating prediction information, and focusing based on the generated prediction information;
Input means for inputting information for comparison with the prediction information generated by the prediction focusing means;
A comparison unit that compares the prediction information generated by the prediction focusing unit and the information input by the input unit;
Comprising
The prediction focusing means performs different processing according to the comparison result of the two information by the comparison means.
A camera characterized by that.

(Corresponding embodiment)
The first to third embodiments correspond to the camera described in (4). In those embodiments, the AF control function 78A1, the moving body speed prediction function 78A3, and the moving body movement direction prediction function 78A4 are used as the prediction focusing means, and the up / down direction key of the key matrix 50 and the AF control function 78A1 are used as the input means. The AF control function 78A1 corresponds to the comparison unit.

(Function and effect)
According to the camera described in (4), it is possible to determine whether or not there is an error in the subject position information by comparing the prediction information with the information input by the input unit. There is no judgment.

  (5) The camera according to (4), wherein the prediction focusing unit displays a prediction error when the comparison unit determines that the two pieces of information are different.

(Corresponding embodiment)
The embodiment related to the camera described in (5) corresponds to the first embodiment.

(Function and effect)
According to the camera described in (5), the photographer can be warned of the occurrence of a prediction error.

(6) The prediction focusing means updates the prediction information based on repeatedly acquired subject position information,
The comparison means compares the new prediction information based on the new subject position information generated by the prediction focusing means and the information on the movement of the subject input by the input means,
The predictive focusing means further performs focusing based on the new prediction information when the comparing means determines that there is no difference between the new prediction information and the input information relating to the movement of the subject. Do,
The camera according to (4), characterized in that:

(Corresponding embodiment)
The embodiment relating to the camera described in (6) corresponds to the second embodiment.

(Function and effect)
According to the camera described in (6), when an error occurs in the subject position information due to the influence of noise or the like, the prediction AF using the previous prediction value can be performed without using the error.

  (7) If the comparison means determines that there is a difference between the two pieces of information, the prediction focusing means relates to the movement of the subject input by the input means instead of the generated prediction information. The camera according to (4), wherein focusing is performed based on an information value.

(Corresponding embodiment)
The embodiment relating to the camera described in (7) corresponds to the third embodiment.

(Function and effect)
According to the camera described in (7), since input information is used even when unreliable prediction information is obtained, even if there is an error in subject position information, a large focus error occurs. Can be prevented.

(8) The prediction information generated by the prediction focusing means and the information input by the input means each include information on the moving direction and moving speed of the subject,
The comparison means compares the information of the subject movement direction and the movement speed of the prediction information generated by the prediction focusing means and the information input by the input means, and at least when the subject movement directions are different, or When the moving speed differs by a predetermined amount or more, it is determined that the prediction information generated by the prediction focusing unit is different from the information input by the input unit.
The camera according to any one of (1) to (4), wherein

(Corresponding embodiment)
The first to third embodiments correspond to the camera described in (8).

(Function and effect)
According to the camera described in (8), it is possible to determine whether or not there is an error in the subject position information by comparing the moving direction or moving speed of the subject. Absent.

(9) further comprising an operating member disposed in the camera housing;
The camera according to any one of claims (1) to (5), wherein the input means inputs a moving speed corresponding to the number of times the operating member is pressed as the information for comparison. .

(Corresponding embodiment)
The embodiment relating to the camera described in (9) corresponds to the first to third embodiments. In these embodiments, the up / down direction key of the cross key in the key matrix 50 corresponds to the operation member.

(Function and effect)
According to the camera described in (9), the moving speed can be easily input by the number of times the operating member is pressed.

(10) It further includes a set of operation members arranged symmetrically on the camera housing,
The input means uses, as information for comparison, an input from one of the operation members as an input indicating that the subject moving direction is a distance, and an input from the other as a direction in which the subject moving direction approaches. Suppose there is an input,
The camera according to any one of (1) to (5), wherein

(Corresponding embodiment)
The embodiment relating to the camera described in (10) corresponds to the first to third embodiments. In these embodiments, the up / down direction key of the cross key in the key matrix 50 corresponds to the operation member.

(Function and effect)
According to the camera described in (10), the moving direction can be easily input by pressing a set of operation members.

  (11) The camera according to (10), wherein the input unit inputs, as the information for comparison, a moving speed according to the number of times each of the set of operation members is pressed.

(Corresponding embodiment)
The first to third embodiments correspond to the camera described in (11). In these embodiments, the up / down direction key of the cross key in the key matrix 50 corresponds to the operation member.

(Function and effect)
According to the camera described in (11), the operation member for inputting the moving direction can also be used for inputting the moving speed.

(12) In a prediction method for generating prediction information by predicting movement of a subject based on subject position information for focusing on a moving subject,
A prediction method characterized in that information relating to movement of the subject input by an operator is compared with the prediction information, and if there is a difference between the two information, prediction error processing is performed.

(Corresponding embodiment)
The embodiment related to the prediction method described in (12) corresponds to the first to third embodiments.

(Function and effect)
According to the prediction method described in (12), it is possible to determine whether or not there is an error in the subject position information by comparing the prediction information with the information input by the operator. There is no misjudgment. Further, by performing the prediction error process, the photographer can be warned of the occurrence of the prediction error.

(13) A program for causing a computer to execute a prediction method for predicting movement of a subject based on subject position information and generating prediction information for focusing on a moving subject,
In the prediction method, the information on the movement of the subject input by the operator is compared with the prediction information, and when there is a difference between the two information, a prediction error process is performed.
A program characterized by that.

(Corresponding embodiment)
The embodiment related to the program described in (13) corresponds to the first to third embodiments.

(Function and effect)
According to the program described in (13), it is possible to determine whether or not there is an error in the subject position information by comparing the prediction information with the information input by the operator. There is no judgment. Further, by performing the prediction error process, the photographer can be warned of the occurrence of the prediction error.

FIG. 1 is a diagram showing a configuration of a digital camera as a camera according to the first embodiment of the present invention. FIG. 2A is a flowchart showing the operation of the AF control function in the system control function of the CPU. FIG. 2B is a flowchart for explaining the detailed operation of the subject direction / speed input process in FIG. FIG. FIG. 3 is a diagram illustrating an example of an icon representing the input result of the moving direction and moving speed of the subject. FIG. 4A is a diagram showing an operation flowchart of a photographing operation by the conventional moving object prediction AF, and FIG. 4B is a moving object prediction AF using the subject movement speed and the advance input of the movement direction in the first embodiment. It is a figure which shows the operation | movement flowchart of imaging | photography operation | movement. FIG. 5 is a diagram showing an operational flowchart of the photographing operation by the moving object prediction AF using the subject movement speed and the prior input of the movement direction in the second embodiment of the present invention. FIG. 6 is a diagram showing an operational flowchart of the photographing operation by the moving object prediction AF using the subject movement speed and the advance input of the movement direction in the third embodiment of the present invention.

Explanation of symbols

    DESCRIPTION OF SYMBOLS 10 ... Digital camera, 12 ... Lens, 14 ... CCD, 16 ... Imaging circuit, 18 ... A / D conversion circuit, 20 ... Correction circuit, 22 ... Frame memory, 24 ... CPU, 24A ... Frame memory control function, 24B ... Recording Medium access function, 24C ... Image compression function, 24D ... Image decompression function, 26 ... Recording buffer, 28 ... Recording medium I / F, 30 ... Recording medium, 32 ... FIFO memory, 34 ... On-screen circuit, 36 ... TFT liquid crystal drive Circuit 38 38 Video output circuit 40 Backlight unit 42 TFT panel 44 Video output terminal 46 LCD panel 48 LCD display circuit 50 Key matrix 52 External data I / F 54 ... Connection detection means 56 ... EEPROM (flash ROM) 5 ... Actuator, 60 ... Actuator drive circuit, 62 ... Lens barrier open / close detection circuit, 64 ... Battery, 66 ... Battery state detection circuit, 68 ... Power supply circuit, 70 ... Backup power supply, 72 ... Strobe, 74 ... Strobe drive circuit, 76 ... Passive AF sensor, 78... CPU, 78A... System control function, 78A1... AF control function, 78A2... Passive AF sensor control function, 78A3.

Claims (13)

Prediction means for predicting movement of a subject based on subject position information and generating prediction information;
Focusing means for focusing based on the prediction information generated by the prediction means;
Input means for inputting information relating to the movement of the subject;
A comparison means for comparing the prediction information generated by the prediction means with information relating to the movement of the subject input by the input means;
Comprising
The prediction means performs a prediction error display when the comparison means determines that there is a difference between the two pieces of information.
A camera characterized by that. Prediction means for predicting movement of a subject based on subject position information and generating prediction information;
Focusing means for focusing based on the prediction information generated by the prediction means;
Input means for inputting information relating to the movement of the subject;
A comparison means for comparing the prediction information generated by the prediction means with information relating to the movement of the subject input by the input means;
Comprising
The prediction means updates the prediction information based on repeatedly acquired subject position information,
The comparison means compares the new prediction information based on the new subject position information generated by the prediction means and the information related to the movement of the subject input by the input means,
The focusing means performs focusing based on the new prediction information when the comparing means determines that there is no difference between the new prediction information and the input information related to the movement of the subject.
A camera characterized by that. Prediction means for predicting movement of a subject based on subject position information and generating prediction information;
Focusing means for focusing based on the prediction information generated by the prediction means;
Input means for inputting information relating to the movement of the subject;
A comparison means for comparing the prediction information generated by the prediction means with information relating to the movement of the subject input by the input means;
Comprising
If the focusing means determines that the two pieces of information are different from each other, the focusing means replaces the prediction information generated by the prediction means with respect to the movement of the subject input by the input means. Focusing based on the value of
A camera characterized by that. Prediction focusing means for predicting movement of the subject based on the subject position information, generating prediction information, and focusing based on the generated prediction information;
Input means for inputting information for comparison with the prediction information generated by the prediction focusing means;
A comparison unit that compares the prediction information generated by the prediction focusing unit and the information input by the input unit;
Comprising
The prediction focusing means performs different processing according to the comparison result of the two information by the comparison means.
A camera characterized by that.   5. The camera according to claim 4, wherein the prediction focusing unit displays a prediction error when the comparison unit determines that the two pieces of information are different. The prediction focusing means updates the prediction information based on repeatedly acquired subject position information,
The comparison means compares the new prediction information based on the new subject position information generated by the prediction focusing means and the information on the movement of the subject input by the input means,
The predictive focusing means further performs focusing based on the new prediction information when the comparing means determines that there is no difference between the new prediction information and the input information relating to the movement of the subject. Do,
The camera according to claim 4.   If the comparison means determines that the two pieces of information are different from each other, the prediction focusing means replaces the generated prediction information with a value of information regarding the movement of the subject input by the input means. The camera according to claim 4, wherein focusing is performed based on the camera. The prediction information generated by the prediction focusing means and the information input by the input means each include information on the moving direction and moving speed of the subject,
The comparison means compares the information of the subject movement direction and the movement speed of the prediction information generated by the prediction focusing means and the information input by the input means, and at least when the subject movement directions are different, or When the moving speed differs by a predetermined amount or more, it is determined that the prediction information generated by the prediction focusing unit is different from the information input by the input unit.
The camera according to claim 1, wherein: Further comprising an operation member arranged in the camera housing,
The camera according to claim 1, wherein the input unit inputs a moving speed corresponding to the number of times the operation member is pressed as the information for comparison. A pair of operation members arranged symmetrically on the camera case;
The input means uses, as information for comparison, an input from one of the operation members as an input indicating that the subject moving direction is a distance, and an input from the other as a direction in which the subject moving direction approaches. Suppose there is an input,
The camera according to any one of claims 1 to 5, wherein:   The camera according to claim 10, wherein the input unit inputs a moving speed corresponding to the number of times each of the set of operation members is pressed as the information for comparison. In a prediction method for generating prediction information by predicting movement of a subject based on subject position information for focusing on a moving subject,
A prediction method characterized in that information relating to movement of the subject input by an operator is compared with the prediction information, and if there is a difference between the two information, prediction error processing is performed. A program for causing a computer to execute a prediction method for predicting movement of a subject based on subject position information and generating prediction information for focusing on a moving subject,
In the prediction method, the information on the movement of the subject input by the operator is compared with the prediction information, and when there is a difference between the two information, a prediction error process is performed.
A program characterized by that.

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