JP2009171428A - Control method and program for digital camera apparatus and electronic zoom - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form the image-clipping frame of a facial image at the center of the detecting position of the focal image, when an electronic zooming function includes a function to detect the facial image. <P>SOLUTION: A digital camera apparatus includes an electronic zooming means for forming an image-clipping frame with a smaller field angle than the maximal field angle in an image screen, and for zooming up the image inside the image-clipping frame by enlarging the image using an imaging process. Further, the apparatus includes a facial-image detecting means for detecting the facial image inside the image screen, and a clipping-frame forming means for forming the image-clipping frame at the position centering on the facial image detected by the facial-image detecting means. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a digital camera device, an electronic zoom control method performed by the digital camera device, and a program for realizing a function for executing the electronic zoom control method.

  In recent years, as a technology trend of digital camera devices, those equipped with a face image detection function tend to increase. In addition, as the number of pixels in the sensor has increased, most models are equipped with an electronic zoom that performs multi-stage enlargement processing by image cutout processing, and optical zoom is installed in small photographic devices such as mobile phones. Many of them have only electronic zoom.

  For example, in human photographing with a photographing apparatus having a face image detection function disclosed in Patent Document 1, as a use application of the face image detection function, focusing according to the face position, white balance with emphasis on the face, The face image detection function is used by performing color adjustment such as AE (After Effect).

JP 2005-348181 A JP-A-6-217187

  Problems to be solved by the invention will be described with reference to FIGS. FIG. 9 is a diagram illustrating an image of a face image detection result. FIG. 10 is a diagram for explaining a problem to be solved by the invention.

  In the process using the electronic zoom function in Patent Document 1, as shown in FIG. 9, a face image detection frame 103 is generated for a face image within the maximum angle of view 101. For the face image detection result 102, as shown in FIG. 10A, the image clipping frame 202 by zooming with respect to the maximum angle of view 201 always performs zooming for image clipping centering on the center of the angle of view. As shown in (b), when the position of the face is detected at the end of the maximum angle of view 203, the detected face image falls out of the image cutout frame 204 when the image cutout zoom process is performed. was there.

  The present invention has been made to solve such a problem. When the electronic zoom function has a face image detection function, an image cutout frame of the face image is generated around the detection position of the face image. It is an object of the present invention to provide a digital camera device and an electronic zoom control method that can be used.

  The first aspect of the present invention is to generate an image cutout frame having an angle of view smaller than the maximum angle of view of the shooting screen, and zoom in by enlarging the image in the image cutout frame using image processing. It is a digital camera device provided with electronic zoom means.

  Here, a feature of the present invention is that a face image detection unit that detects a face image in the shooting screen, and the image clipping frame at a position centering on the face image detected by the face image detection unit. And a cutout frame generation means for generating.

  According to a second aspect of the present invention, the digital camera device generates an image clipping frame having an angle of view smaller than the maximum angle of view of the shooting screen, and enlarges the image in the image clipping frame using image processing. This is an electronic zoom control method used when zooming up.

  Here, the feature of the present invention is that the face image detection means detects the face image in the shooting screen, and the cutout frame generation means focuses on the face image detected by the face image detection means. The image cutout frame is generated at the position to be processed.

  According to the third aspect of the present invention, by installing the information processing apparatus in the information processing apparatus, an image cutout frame having a field angle smaller than the maximum field angle of the shooting screen is generated in the information processing apparatus, and the image in the image cutout frame is displayed. This is a program for realizing an electronic zoom function of a digital camera device that performs zoom-up by enlarging using image processing.

  Here, a feature of the present invention is that a face image detection function for detecting a face image in the shooting screen and the image clipping frame at a position centering on the face image detected by the face image detection function. And a cutout frame generation function for generating.

  According to the present invention, when the electronic zoom function has a face detection function, an image cutout frame of a face image can be generated around the detection position of the face image.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram of the digital camera device according to the first embodiment. FIG. 2 is a block diagram of the electronic zoom function of the first embodiment.

  As shown in FIG. 1, the digital camera device according to the first embodiment includes a camera sensor 1, a data bus 2, an image processing unit 3, a CPU 4, a display unit 5, a key operation unit 6, and a memory unit 7.

  The camera sensor 1 is an image pickup device composed of a CCD or C-MOS, and an image through an optical lens (not shown) is formed on the camera sensor 1, and the formed image is converted into an electrical signal. Image data. The camera sensor 1 also exchanges image data with the image processing unit 3 via the data bus 2. The key operation unit 6 is a device for the user to input operations such as activation of the digital camera device, shooting, zooming operation, or image storage.

  The image processing unit 3 performs image data processing such as face image detection processing, image cutout frame display processing, or zoom processing. Further, the image processing unit 3 also holds the angle of view data. The angle-of-view data held by the image processing unit 3 is zoom angle-of-view data that is actually cut out with the face image as the center at the time of zoom execution, and center cut-out angle-of-view data that is referenced when there is no face image.

  The CPU 4 performs an operation input from the key operation unit 6 to the image acquisition command or data transfer command to the camera sensor 1, a face image detection processing command or zoom processing command or data transfer command to the image processing unit 3, and the memory unit 7. Data transfer and storage processing.

  The image processing unit 3 or the CPU 4 has a block configuration of the electronic zoom function of the present invention as shown in FIG. In the present embodiment, the block configuration of the electronic zoom function shown in FIG.

  Next, the electronic zoom function of the present invention will be described with reference to FIG. The electronic zoom unit 12 generates an image cutout frame having an angle of view smaller than the maximum view angle of the shooting screen, and zooms up by enlarging the image within the image cutout frame using image processing. The face image detection unit 10 detects a face image within the shooting angle of view. The cutout frame generation unit 11 generates an image cutout frame at a position centered on the face image detected by the face image detection unit 10.

  Furthermore, when a plurality of face images are simultaneously detected by the face image detection unit 12, the barycentric position calculation unit 13 calculates the barycentric position in a figure formed by connecting the centers of the plurality of face images. In this case, the cut-out frame generation unit 11 is centered on the gravity center position calculated by the gravity center position calculation unit 13 and is at the farthest position from the gravity center position among the plurality of face images detected by the face image detection unit 10. An image cutout frame is generated at a position including the face image.

  Further, the zoom speed adjustment unit 14 adjusts the enlargement speed when enlarging the image clipping frame using image processing based on the zoom speed adjustment operation input that is input by the user operating the key operation unit 6. Adjust the zoom speed.

  Furthermore, the intermediate zooming unit 15 captures an image at an arbitrary timing in the process of enlarging the image clipping frame using image processing based on a shooting instruction input (shutter input) input by the user operating the key operation unit 6. Can be implemented.

  For example, the user sets the slowest zoom speed with respect to the zoom speed adjusting unit 14 and determines that an image that seems to be the best shot was obtained while zooming in slowly. If it performs, the image in the zoom-up position at that time can be image | photographed.

  According to this, since the image of the subject can be photographed at an arbitrary timing in the process of zooming up the whole body image → the upper body image → the chest image → the face image, the photographing range is limited to the face image. In addition, the user's willingness to create can be satisfied. In addition, when the subject is moving, it is difficult to track the face image suddenly, so this function is useful for grasping the limit that can be tracked in the process of gradually zooming up from the whole body image. It is.

  Further, the center position adjusting unit 16 is based on the center position adjustment input input by the user operating the key operation unit 6, and the position of the face image within the image clipping frame is specified by the operation input from the center position. In addition, the face image can be biased within a range that does not deviate from the image cutout frame.

  The key operation unit 6 includes up / down / left / right cross-shaped push button switches, and the user operates the cross-shaped push button switch so that the face image is displayed in an image clipping frame in any direction, up / down / left / right. The face image can be biased without departing from the range. Thereby, the user's willingness to create can be satisfied without limiting the position of the face image to the center of the screen.

  As described above, in the digital camera device having the face image detection function and the electronic zoom function, the first embodiment can determine the cutout position according to the position of the detected face image and perform zoom processing. . FIG. 3 is a conceptual diagram of zoom processing according to the first embodiment. That is, as shown in FIG. 3, by changing the image clipping frames 302 (FIG. 3A) and 304 (FIG. 3B) according to the position of the face image based on the face image detection frame 103, Even if the cut-out zoom process is executed, it is possible to perform a preview or shooting without removing a person's face from the angle of view. Reference numerals 301 and 303 indicate the maximum angle of view.

  Next, a flow of processing of electronic zoom using face image detection in the first embodiment is shown. FIG. 4 is a flowchart showing a flow of processing of electronic zoom using face image detection. As shown in FIG. 4, when camera activation is input by key operation of the key operation unit 6 (step S <b> 1), the camera sensor 1 is activated by a command from the CPU 4 (step S <b> 2), and a preview on the display unit 5 is displayed. Display is started (step S3).

  The face image detection unit 10 of the image processing unit 3 starts face image detection processing on the image sent from the camera sensor 1 (step S4), and when a face image is detected (Yes in step S5), the face An image detection frame is displayed (step S6), and the angle of view of the image cutout frame that matches the face position is calculated (step S7). At this time, the zoom angle of view data held in the electronic zoom unit 12 of the image processing unit 3 is updated (steps S8 and S18).

  If no face image is detected (No in step S5), the central cut-out view angle data stored in the electronic zoom unit 12 of the image processing unit 3 is referred to (steps S16 and S17), and the zoom view angle data is displayed. Is updated (steps S8 and S18).

  When zoom processing is executed from the key operation unit 6 (Yes in step S9), an image clipping frame is generated based on the zoom angle of view data (step S18) (step S10), and the generated image clipping frame is displayed. The display 5 is switched and displayed (step S11).

  That is, the display unit 5 that has displayed the maximum range that can be photographed so far at the maximum angle of view displays the image within the image clipping frame at the maximum angle of view. As a result, the image in the image cutout frame that has been shot small in the maximum range that can be shot is enlarged and displayed by displaying the image in the image cutout frame at the maximum angle of view.

  When the enlargement zoom process is not executed (No in step S9), the image cutout frame generation (step S10) and the display of switching the image within the image cutout frame to the maximum angle of view (step S11) are not performed. Thereafter, when the shutter button is pressed (Yes in step S12), a captured image at the displayed angle of view is acquired (step S19), and the captured image is stored in the memory unit 7 (step S20).

  Thereafter, if the preview is continued (Yes in step S13), the preview and face image detection process is continued (step S5). If the preview is not continued (No in step S13), the camera sensor 1 is stopped (step S14), and the camera device is stopped (step S15).

  Here, the zoom speed adjustment by the zoom speed adjusting unit 14 is performed in the process of switching from the cutout frame generation in step S10 to the cutout frame display in step S11. That is, if there is a zoom speed adjustment instruction (Yes in step S20), in steps S10 and S11, the display of the maximum shooting range is not instantaneously switched from the display of the maximum shooting range to the display in the image clipping frame. Zoom speed adjustment is executed by gradually enlarging the image in the image cutout frame over the set time for display in the image cutout frame (step S21).

  Further, the shooting by the zoom intermediate shooting unit 15 is gradually performed over a set time from the display of the maximum shooting range to the display in the image clipping frame by the zoom speed adjustment unit 14 between steps S10 and S11. In the middle of enlarging the image in the image cutout frame (step S21), if there is an instruction for photographing during zooming (Yes in step S22), the process jumps to the captured image acquisition in step S19.

  Next, an image clipping frame setting method of the clipping frame generation unit 11 will be described with reference to FIG. FIG. 5 is a diagram illustrating an image clipping frame generation procedure of the clipping frame generation unit 11. First, as shown in FIG. 5A, an image cutout frame 802 whose face is the center is determined from the face image detection frame 801. Reference numeral 803 denotes an image cutout frame before convergence.

  As shown in FIG. 5B, the center cutout is performed until the side 811 where one side of the image cutout frame 812 overlaps with the image cutout frame 802, and then the side 811 overlapped with the image cutout frame 802 is fixed. As shown in FIG. 5D, the image clipping frame 822 is gradually narrowed until the other sides overlap with the image clipping frame 802, and finally, as shown in FIG. This is realized by performing the clipping process up to an image clipping frame 831 that matches the frame 821.

(Description of effects of the first embodiment)
As described above, the first embodiment has the following effects.
The first effect is that it is possible to prevent the face image of a person from deviating from the angle of view when the angle of view is narrowed by a zoom operation during shooting of the person.

  The second effect is that the zoom function according to the first embodiment (block configuration after the face image detection unit 10 in FIG. 2) can be incorporated in the image processing unit 3, so that it is cheap and easy without hardware change. realizable. Note that the zoom function according to the first embodiment may be incorporated in the CPU 4 instead of the image processing unit 3.

  The third effect is that the zoom function according to the first embodiment can be incorporated into the image processing unit 3 (or the CPU 4), so that it can be easily realized with a small device having a camera function such as a mobile phone. is there.

(Second embodiment)
A second embodiment of the present invention will be described with reference to FIG. FIG. 6 is a diagram for explaining a zoom procedure according to the second embodiment. As a second embodiment, the basic configuration is as described above, but an embodiment in which an optical zoom and an electronic zoom can be combined in the zoom processing portion will be described.

  After the face image is detected, as shown in FIG. 6, the optical zoom is performed up to the region 603 where the face image does not deviate from the angle of view, and the electronic zoom process described in the first embodiment is performed to match the face image position. An image cutout frame 605 is generated. Thereby, it is possible to perform zoom-up processing with minimal image quality degradation due to electronic zoom processing. Here, reference numeral 601 denotes a maximum field angle, reference numeral 602 denotes a face image detection frame, and reference numeral 604 denotes a zoom-up range by optical zoom.

  A technique similar to Patent Document 2 is disclosed for an embodiment in which optical zoom and electronic zoom are combined. However, when performing the electronic zoom process, the technique for performing zoom speed adjustment and zoom in-progress shooting described in the first embodiment is not disclosed in Patent Document 2, and if these techniques are included, The difference between the second embodiment and the technique of Patent Document 2 is clear.

(Description of effects of the second embodiment)
According to the second embodiment, the electronic zoom function of the first embodiment can be effectively used also in a digital camera device having an optical zoom function and an electronic zoom function.

(Third embodiment)
As a third embodiment of the present invention, an embodiment devised with respect to a method for setting an image clipping frame will be described with reference to FIG. FIG. 7 is a diagram for explaining an image clipping frame setting method according to the third embodiment. In the basic configuration, as shown in FIG. 5, center clipping is performed at the initial stage of zooming, but in the third embodiment, as shown in FIG. 7, from the maximum field angle 901 to the image clipping frame 904 on each side. Are cut at the same ratio (steps S911 and S921), and the image is cut out until the image cutout frame 902 and the image cutout frame 904 finally match (step S931).

(Explanation of effects of the third embodiment)
According to the third embodiment, it is possible to shorten the time until the final image cutout frame is generated as compared with the first embodiment, and thus it is possible to shorten the processing time of the electronic zoom.

(Fourth embodiment)
A fourth embodiment of the present invention will be described with reference to FIG. FIG. 8 is a diagram for explaining processing when a plurality of face images are detected. The fourth embodiment is an embodiment regarding processing when a plurality of face images are simultaneously detected by the camera sensor 1.

  As shown in FIG. 8, when a plurality of face images are detected, the center-of-gravity position calculation unit 13 calculates a center-of-gravity position 701 in a figure formed by connecting the centers of the plurality of face positions, and the center of gravity is calculated. By generating an image cutout frame 702 centered on the position 701 and performing zooming, it is possible to perform shooting at an angle of view in which faces of a plurality of persons are arranged in a balanced manner within the angle of view. At this time, the image cutout frame 702 is generated at a position including the face image that is farthest from the center of gravity position among the plurality of face images detected by the face image detection unit 2.

(Description of the effect of the fourth embodiment)
According to the fourth embodiment, the electronic zoom function of the present embodiment can also be applied to shooting for a plurality of persons.

(Fifth embodiment)
The face image detection unit 10 in the first to fourth embodiments is a functional block having a function of detecting a human face image, but instead of this, a function of detecting a subject such as an animal or a flower other than a person. It is also possible to provide a functional block having

(Explanation of the effect of the fifth embodiment)
According to the fifth embodiment, subjects other than human face images such as animals and flowers can be detected, and the electronic zoom function of this embodiment can be used for the detected subjects.

(Program embodiment)
An embodiment of a program that, when installed in an information processing apparatus, causes the information processing apparatus to realize a function corresponding to the digital camera apparatus of the present embodiment will be described.

  By recording the program of the present embodiment on a recording medium, the information processing apparatus can install the program of the present embodiment using the recording medium. Alternatively, the program of this embodiment can be directly installed on the information processing apparatus via a network from a server that holds the program of this embodiment.

  The program according to the present embodiment includes not only a program that can be directly executed by the information processing apparatus but also a program that can be executed by being installed on a hard disk or the like. Also included are those that are compressed or encrypted.

(Description of the effect of the program embodiment)
Thereby, the function corresponding to the image processing unit 2 or the CPU 4 of the present embodiment can be realized using the information processing apparatus. The information processing apparatus is, for example, a general-purpose CPU or a microcomputer apparatus.

  According to the present invention, when the electronic zoom function alone or a small camera device centering on the electronic zoom function, such as a mobile phone, has a face image detection function, the image cutout frame is detected as a face image. It can be generated around the position.

1 is a block configuration diagram of a digital camera device according to a first embodiment. The block block diagram of the electronic zoom function of 1st embodiment. It is a conceptual diagram of the zoom process of 1st embodiment. It is a flowchart which shows the flow of a process of the electronic zoom using the face image detection in 1st embodiment. It is a figure which shows the image cut frame production | generation procedure of the cut frame production | generation part of 1st embodiment. It is a figure for demonstrating the zoom procedure of 2nd embodiment. It is a figure for demonstrating the setting method of the image clipping frame of 3rd embodiment. It is a figure for demonstrating the process when the some face image of 4th embodiment is detected. It is a figure which shows the image of a face image detection result. It is a figure for demonstrating the subject which invention will solve.

Explanation of symbols

1 Camera Sensor 2 Data Bus 3 Image Processing Unit 4 CPU
DESCRIPTION OF SYMBOLS 5 Display part 6 Key operation part 7 Memory part 10 Face image detection part 11 Cutout frame production | generation part 12 Electronic zoom part 13 Gravity center position calculation part 14 Zoom speed adjustment part 15 Zoom intermediate photography part 16 Center position adjustment part 101,201,203, 301, 302, 601, 901 Maximum angle of view 102 Face image detection results 103, 801, 602, 903 Face image detection frames 202, 204, 603, 605, 702, 802, 803, 821, 822, 831, 902, 904, 911, 921, 931 Image cutout frame 603 Region 604 Zoom-up range 701 by optical zoom centroid position 811 side

Claims (15)

Digital camera apparatus provided with electronic zoom means for generating an image cutout frame with a smaller angle of view than the maximum view angle of the shooting screen, and zooming up by enlarging the image in the image cutout frame using image processing In
Face image detection means for detecting a face image in the shooting screen;
A digital camera apparatus comprising: a cutout frame generation unit configured to generate the image cutout frame at a position centered on the face image detected by the face image detection unit. When a plurality of face images are detected at the same time by the face image detecting means, a center-of-gravity position calculating means for calculating a center-of-gravity position in a figure formed by connecting the centers of the plurality of face images,
The cutout frame generation unit is configured to select a face image at a position farthest from the barycentric position among the plurality of face images detected by the face image detecting unit with the barycentric position calculated by the barycentric position calculating unit as a center. The digital camera device according to claim 1, further comprising means for generating an image cutout frame at a position including the image cutout frame.   The digital camera device according to claim 1, further comprising a zoom speed adjusting unit that adjusts an enlargement speed when the image cutout frame is enlarged using image processing.   The digital camera device according to any one of claims 1 to 3, further comprising zoom intermediate photographing means for performing photographing at an arbitrary timing in a process in which the image cutout frame is enlarged using image processing.   The center position adjustment means for biasing the position of the face image in the image cutout frame in the direction specified by the operation input from the center position within a range in which the face image does not deviate from the image cutout frame. 5. The digital camera device according to any one of 4. An electronic device used when a digital camera device generates an image cutout frame with an angle of view smaller than the maximum angle of view of a shooting screen, and zooms up by enlarging an image in the image cutout frame using image processing. In the zoom control method,
A face image detecting means detects a face image in the shooting screen;
An electronic zoom control method, wherein the cutout frame generation unit generates the image cutout frame at a position centered on the face image detected by the face image detection unit. When a plurality of face images are detected simultaneously by the face image detecting means, the center of gravity position calculating means calculates the center of gravity position in the figure formed by connecting the centers of the plurality of face images,
The cutout frame generation unit is configured to select a face image that is centered on the barycentric position calculated by the barycentric position calculating unit and that is farthest from the barycentric position among the plurality of face images detected by the face image detecting unit. The method for controlling an electronic zoom according to claim 6, wherein an image cutout frame is generated at a position including the image cutout frame.   The electronic zoom control method according to claim 6 or 7, wherein the zoom speed adjusting means adjusts an enlargement speed when the image cutout frame is enlarged using image processing.   9. The electronic zoom control method according to claim 6, wherein the image capturing means during zooming performs image capturing at an arbitrary timing in a process in which the image cutout frame is enlarged using image processing. 10.   The center position adjusting means biases the position of the face image in the image cutout frame in the direction specified by the operation input from the center position within a range in which the face image does not deviate from the image cutout frame. The electronic zoom control method according to claim 1. By installing on an information processing device,
Realizes an electronic zoom function of a digital camera device that generates an image cutout frame with a smaller angle of view than the maximum angle of view of the shooting screen, and zooms up by enlarging the image within this image cutout frame using image processing In the program to
A face image detection function for detecting a face image in the shooting screen;
A cutout frame generation function for generating the image cutout frame at a position centered on a face image detected by the face image detection function. When a plurality of face images are detected simultaneously by the face image detection function, a center-of-gravity position calculation function for calculating a center-of-gravity position in a figure formed by connecting the centers of the plurality of face images is realized,
As the cutout frame generation function, a face image that is centered on the center of gravity position calculated by the center of gravity position calculation function and that is at the farthest position from the center of gravity position among the plurality of face images detected by the face image detection function. The program according to claim 11, which realizes a function of generating an image cutout frame at a position including the image cutout frame.   The program according to claim 11 or 12, which realizes a zoom speed adjustment function for adjusting an enlargement speed when the image cutout frame is enlarged using image processing.   The program according to any one of claims 11 to 13, which realizes a zoom intermediate shooting function for performing shooting at an arbitrary timing in a process in which the image cutout frame is enlarged using image processing.   12. A center position adjustment function is implemented that biases the face image position within the image cutout frame in a direction specified by an operation input from the center position within a range in which the face image does not deviate from the image cutout frame. 14. The program according to any one of 14.

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