JP2007336125A - Imaging device and its controlling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging device which can prevent incorrect detection and failure of detection of a face image, and also to provide its controlling method. <P>SOLUTION: An object is imaged to acquire CCD-RAW data (step 51), and a face image is extracted from a RAW object image (step 52). Signal processing including YC data production processing is performed on the CCD-RAW data (step 53), and a face image is extracted from a YC object image (step 54). Using the face image obtained from the RAW object image and the face image obtained from the YC object image, incorrect detection suppression processing (step 55) and failure-of-detection suppression processing (step 56) are performed to obtain face information indicating the position of a final face image. Since the face information is obtained by extracting the face image using two types of data, incorrect detection and failure of detection can be prevented. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an imaging apparatus and a control method thereof.

An apparatus that detects a target image portion such as a face image from a subject image has been considered (Patent Document 1).
JP 2005-269563 A

  However, the detection accuracy is not always high.

  An object of the present invention is to improve the detection accuracy of a target image portion.

  An imaging apparatus according to a first aspect of the present invention is a solid-state electronic imaging apparatus that images a subject and outputs color RAW data representing the subject image, and includes predetermined YC data generation for the color RAW data output from the solid-state electronic imaging apparatus. A signal processing circuit that performs the signal processing and outputs YC data; a first target image detection unit that detects a predetermined target image from a RAW subject image represented by the color RAW data output from the solid-state electronic imaging device; And a second target image detecting means for detecting a predetermined target image from the YC subject image represented by the YC data output from the signal processing circuit. The first target image detection unit and the second target image detection unit may be the same.

  The first invention also provides a control method suitable for the imaging apparatus. That is, in this method, the solid-state electronic imaging device images a subject and outputs color RAW data representing the subject image, and the signal processing circuit outputs YC data for the color RAW data output from the solid-state electronic imaging device. Predetermined signal processing including generation is performed, YC data is output, and the first target image detection unit extracts a predetermined target image from the RAW subject image represented by the color RAW data output from the solid-state electronic imaging device. The second target image detecting means detects a predetermined target image from the YC subject image represented by the YC data output from the signal processing circuit.

  According to the first invention, color RAW data is output from the solid-state electronic imaging device. Predetermined signal processing including YC data generation is performed on the color image data. According to the first invention, the first target image detection process using color RAW data and the second target image detection process using YC data are performed. The target image detection process is performed using two types of data. By determining the position of the target image using the detection results, the accuracy of the determined position of the target image is increased.

  The position of the predetermined target image in the subject image captured by the solid-state electronic imaging device from the target image detected by the first target image detection unit and the target image detected by the second target image detection unit. You may make it further provide the 1st position determination means to determine.

  For example, the second target image detecting means detects a predetermined target image having a target image quality equal to or higher than a first threshold value from a YC subject image represented by YC data output from the signal processing circuit. Is. In this case, when the target image likelihood of the predetermined target image detected by the second target image detection means is equal to or higher than the second threshold value higher than the first threshold value, the second threshold value is set. The position of the predetermined target image having the above target image quality is determined as the position of the target image, and when the target image likelihood of the detected predetermined target image is less than the second threshold value, A predetermined image having a target image quality less than the second threshold value in response to an image portion corresponding to the predetermined target image detected by the target image detecting unit being detected by the first target image detecting unit; It is preferable to include a second position determining unit that determines the position of the target image as the position of the target image.

  The first target image detection means, for example, obtains a predetermined target image having a target image quality equal to or higher than a first threshold value from a RAW subject image represented by color RAW data output from the solid-state electronic imaging device. It is to detect. In this case, the RAW image includes a predetermined target image having a target image likelihood that is greater than or equal to a second threshold value that is greater than the first threshold value, and the target image likelihood of the target image of the RAW image. It is preferable to include a replacement unit that replaces the position of the corresponding target image of the YC image with the position of the target image of the RAW image when the target image of the target image of the YC image is larger than the target image.

  As described above, the first target image detection means has a target image quality equal to or higher than a first threshold value from a RAW subject image represented by color RAW data output from the solid-state electronic imaging device, for example. The second target image detecting means detects a predetermined target image, and the second target image detecting means detects, for example, a target equal to or higher than a second threshold value from a YC subject image represented by YC data output from the signal processing circuit. A predetermined target image having an image quality is detected. In this case, the predetermined image portion detected by the second target image detection means corresponds to the predetermined target image detected in the RAW subject image represented by the color RAW data output from the solid-state electronic imaging device. It is preferable that a registration unit is provided for registering the position of the corresponding target image when there is no target image to be processed.

  YC data output from the signal processing circuit, data indicating the position of the target image detected by the first target image detection means, and the position of the target image detected by the second target image detection means You may make it further provide the recording control means to link | relate with the data shown, and to record on a recording medium.

  According to a second aspect of the present invention, there is provided a solid-state electronic image pickup apparatus that picks up an image of a subject and outputs color RAW data representing the image of the object. First target image detecting means for detecting the target image, a signal processing circuit for performing predetermined signal processing including YC data generation from the color RAW data output from the solid-state electronic imaging device, and outputting YC data, the signal Recording control means for recording the YC data output from the processing circuit and the data indicating the position of the target image detected by the first target image detection means in association with each other, and the YC recorded on the recording medium A second pair that reads data and detects a predetermined target image from the YC subject image represented by the read YC data. Based on the image detection means, data indicating the position of the target image recorded on the recording medium, and data indicating the position of the predetermined target image detected by the second target image detection means, the predetermined target image Position determining means for determining the position of

  The second invention also provides a control method suitable for the imaging apparatus. That is, this method captures a subject and outputs color RAW data representing the subject image, and a predetermined target image from the RAW subject image represented by the color RAW data output from the solid-state electronic image pickup device. A first target image detecting means for detecting image data, a signal processing circuit for performing YC data generation from color RAW data output from the solid-state electronic imaging device and outputting YC data, and the signal processing circuit Recording control means for associating the output YC data and data indicating the position of the target image detected by the first target image detection means with each other, and recording the YC data recorded on the recording medium , A second target image for detecting a predetermined target image from the YC subject image represented by the read YC data And the data indicating the position of the target image recorded on the recording medium and the data indicating the position of the predetermined target image detected by the second target image detecting means, A position determining means for determining the position is provided.

  According to the second invention, the target image is detected using the color RAW data. Further, color RAW data is subjected to signal processing to generate YC data. Data indicating the position of the detected target image and the generated YC data are associated with each other and recorded on the recording medium. When the YC data is read from the recording medium, the target image is detected using the read YC data, and the target image is detected. The position of the target image is determined from the data indicating the position of the detected target image and the data indicating the position recorded on the recording medium. Since the position of the target image is determined using the color RAW data and the YC data, the accuracy of the position of the target image is improved.

  An image pickup apparatus according to a third aspect of the present invention is a solid-state electronic image pickup apparatus that picks up an image of a subject and outputs image data representing the image of the object. Pre-imaging control means for controlling the solid-state electronic imaging device, the subject imaged based on the main imaging command, and the data amount of image data to be output is the data amount of image data obtained at the time of pre-imaging control A main imaging control means for controlling the solid-state electronic imaging device so as to be more than a predetermined target image from a pre-subject image represented by image data output from the solid-state electronic imaging device under the pre-imaging control. A first target image detecting means for detecting a main imaging subject image represented by image data output from the solid-state electronic imaging device under the main imaging control. Based on second target image detection means for detecting a predetermined target image, the predetermined target image detected by the first target image detection means, and the predetermined target image detected by the second target image detection means Position determination means for determining the position of the target image, data indicating the position determined by the position determination means, and image data output from the solid-state electronic imaging device under the control of the imaging control means It is characterized by comprising a recording control means for recording in association with a recording medium.

  The third invention also provides a control method suitable for the imaging apparatus. That is, in this method, the solid-state electronic imaging device images a subject and outputs image data representing the subject image, and the pre-imaging control unit images the subject based on the pre-imaging command and outputs the image data. The solid-state electronic imaging device is controlled so that the data amount of the image data is reduced, and the imaging control unit images the subject based on the imaging command, and the data amount of the output image data is the pre-imaging control. The solid-state electronic imaging device is controlled to be larger than the data amount of the obtained image data, and the first target image detection means outputs image data output from the solid-state electronic imaging device under the pre-imaging control. A predetermined target image is detected from the pre-subject image represented by the second object image detection means, and the second target image detection means is configured to detect the target image based on the image data output from the solid-state electronic imaging device under the main imaging control. A predetermined target image is detected from the main captured subject image represented by the position detection means, and the position determination means is detected by the predetermined target image detected by the first target image detection means and the second target image detection means. The position of the target image is determined based on the predetermined target image, and the recording control means controls the solid-state electronic image pickup device under the control of the data determined by the position determination means and the image pickup control means. Are recorded on a recording medium in association with each other.

  According to the third invention, pre-imaging and main imaging are performed. The data amount of image data obtained during pre-imaging is smaller than the data amount of image data obtained during main imaging. Therefore, the accuracy of detecting the target image using the image data obtained during the main imaging is higher than the accuracy of detecting the target image using the image data obtained during the pre-imaging. Since the target image is detected by using two different types of image data and the position of the target image is determined, the detection accuracy is increased.

  The image data representing the subject image used for the detection process by the first target image detection means and the image data representing the subject image used for the detection process by the second target image detection means are, for example, color RAW data. . In this case, a signal processing circuit that performs predetermined signal processing including YC data generation on the image data output from the solid-state electronic imaging device under the control of the imaging control means, and outputs YC data; and It is preferable to further include third target image detection means for detecting a predetermined target image from the subject image represented by the YC data output from the signal processing circuit. The position determination means includes a predetermined target image detected by the first target image detection means, a predetermined target image detected by the second target image detection means, and the third target image detection. The position of the target image will be determined based on the predetermined target image detected by the means.

  When the image data representing the subject image used for the detection process by the first target image detection unit and the image data representing the subject image used for the detection process by the second target image detection unit are color RAW data, A signal processing circuit that performs predetermined signal processing including YC data generation on the image data output from the solid-state electronic imaging device under the control of the imaging control unit, and outputs YC data; Good. In this case, the recording control means will record the data indicating the position determined by the position control means and the YC data output from the signal processing circuit in association with each other on the recording medium.

  Third target image detection means for reading a YC data recorded on the recording medium and detecting a predetermined target image from a subject image represented by the read YC data, and a target image recorded on the recording medium Position determining means for determining the position of the predetermined target image based on the data indicating the position and the data indicating the position of the predetermined target image detected by the second target image detecting means may be further provided. Good.

  An imaging device according to a fourth aspect of the invention is a solid-state electronic imaging device that outputs image data representing a subject image by imaging the subject, and an image that is captured and output in accordance with the setting of the imaging mode. The through image imaging control means for controlling the solid-state electronic imaging device so that the data amount of the data becomes the data amount for the through image, the subject is imaged based on the moving image mode command, and the data amount of the output image data is Moving image mode imaging control means for controlling the solid-state electronic imaging device so as to be larger than the data amount for the through-image, and is represented by image data output from the solid-state electronic imaging device under the through-image imaging control. First target image detecting means for detecting a predetermined target image from the subject image, and output from the solid-state electronic imaging device under the moving image mode imaging control. Characterized in that it comprises a second object image detection means for detecting a predetermined object image from the subject image represented by the image data.

  The fourth invention also provides a control method suitable for the imaging apparatus. That is, in this method, the solid-state electronic image pickup device picks up the subject and outputs image data representing the subject image, and the through image pickup control means picks up the subject according to the setting of the image pickup mode. Then, the solid-state electronic imaging device is controlled so that the data amount of the output image data becomes the data amount for the through image, and the moving image capturing control means captures and outputs the subject based on the moving image mode command. The solid-state electronic imaging device is controlled so that the data amount of the image data to be larger than the data amount for the through image, and the first target image detecting means is configured to control the solid-state electronic device under the through image imaging control. A predetermined target image is detected from the subject image represented by the image data output from the imaging device, and the second target image detection means performs the solid-state electronic imaging under the moving image mode imaging control. Predetermined target image from the subject image represented by the image data to be placed et output detects a.

  According to the fourth aspect, when the imaging mode is set, image data for a through image is obtained. Also, when a moving image mode command is given, moving image data having a data amount larger than the data amount of through image data is obtained. The target image detection process is performed using the image data for the through image and the image data for the moving image. Since the target image detection process is performed using image data having two different data amounts, the detection accuracy is improved.

  The image data is, for example, color RAW data.

  FIG. 1 shows an embodiment of the present invention and is a block diagram showing an electrical configuration of a digital still camera.

  The overall operation of the digital still camera is controlled by the system control circuit 1.

  The digital still camera has a mode dial 7 for setting modes such as an image pickup mode and a playback mode, a shutter button 8, an image display on / off switch 9 for controlling on / off of the liquid crystal display device 35, and a color. A temperature setting switch 10, an operation switch 11, and a memory card attachment / detachment detection circuit 12 are provided. Signals output from these switches are input to the system control circuit 1. Connected to the system control circuit 1 are a memory 2 for temporarily storing data, a display device 3 for displaying predetermined information such as a frame number, a nonvolatile memory 4 and a communication circuit 5. An antenna 6 is connected to the communication circuit 6. Further, the system control circuit 1 includes a power supply control circuit 13, and the power supplied from the power supply 14 is given to each circuit.

  The digital still camera in this embodiment includes an angle sensor 19. The angle sensor 19 detects the vertical direction (upright direction) of the subject image obtained by imaging.

  The digital still camera includes a CCD 23 controlled by a timing generation circuit 33. In front of the CCD 23, a zoom lens 21 that is controlled to open and close by a barrier control circuit 15 and whose zoom amount is controlled by a zoom control circuit 16 and that is positioned at an in-focus position by a distance measurement control circuit 17. An aperture 22 whose aperture value is controlled by the exposure control circuit 18 is provided.

  When the imaging mode is set, a subject is imaged (through-image imaging) at a constant cycle, and a video signal representing the subject image is output from the CCD 23 at a constant cycle. The video signal output from the CCD 23 is given to the analog / digital conversion circuit 24 and converted into CCD-RAW data.

  The CCD-RAW data is given to the face extraction circuit 26. In the face extraction circuit 26, a face image is extracted from the subject image obtained by imaging. The face extraction circuit 26 and the system control circuit 1 can perform serial communication, and face extraction processing is performed based on a control signal provided from the system control circuit 1 by serial communication. Data representing the result of the face extraction process is also given to the system control circuit 1.

  The face extraction process in the face extraction circuit 26 is performed by a process of determining whether or not a frame having various sizes is scanned on the subject image and an image portion included in the frame is a face image. The image portion included in the frame is digitized as the likelihood of a face image, and if the digitized score is equal to or greater than a predetermined threshold value, it is determined that the image portion is a face image. Needless to say, the face image detects not only a front-facing image but also a tilted face image, a lateral face image, etc., as will be described later.

  The CCD-RAW data output from the analog / digital conversion circuit 24 is input to the image processing circuit 25, and predetermined signal processing such as gamma correction, luminance data, and color difference data generation processing is performed. Luminance data and color difference data (YC data) output from the image processing circuit 25 are input to the face extraction circuit 26. In the face extraction circuit 26, a face image is extracted from a subject image (YC subject image) represented by YC data. Data indicating the extracted result is also input to the system control circuit 1. As described above, in the digital still camera according to this embodiment, the face image extraction process from the RAW subject image represented by the CCD-RAW data and the face image from the YC subject image represented by the YC data are processed. The extraction process can be executed.

  The YC data is also input to the color temperature detection circuit 27. The color temperature detection circuit 27 detects the color temperature of the subject image, and the color balance is adjusted under the control of the system control circuit 1.

  The YC data is temporarily stored in the image display memory 29 under the control of the memory control circuit 28. The YC data is read from the image display memory 29 and supplied to the digital / analog conversion circuit 34, thereby returning it to an analog video signal. By applying the analog video signal to the liquid crystal display device 35, a subject image obtained by imaging is displayed on the display screen of the liquid crystal display device 35.

  When the shutter button 8 is pressed, the YC data output from the analog / digital conversion circuit 24 as described above is temporarily stored in the memory 30 by the memory control circuit 28. The YC data is read from the memory 30 and compressed by the compression / decompression circuit 31. The compressed YC data is given to the memory card 32 and recorded.

  When the reproduction mode is set, the compressed YC data recorded on the memory card 32 is read and decompressed by the compression / decompression circuit 31. The decompressed YC data is converted into a video signal and applied to the liquid crystal display device 35, whereby the subject image represented by the image data read from the memory card 32 is displayed on the display screen of the liquid crystal display device 35. Is done.

  2A, 2B, and 2C are examples of face images.

  (A) shows an example of a face image tilted to the left (tilt of −30 degrees), (B) shows an example of an erect face image (tilt of 0 degrees), and (C) tilted to the right ( An example of a face image is shown. Thus, the tilt indicates the tilt angle of the face when the face is facing the front.

  3A, 3B, and 3C are also examples of face images.

  (A) shows an example of a face image facing left, (B) shows an example of a front face image, and (C) shows an example of a face image facing right. Thus, the direction indicates an open direction from the front centering on the vertical line.

  FIG. 4 is an example of a RAW subject image.

  The subject image represented by the CCD-RAW data obtained as described above is referred to as a RAW subject image. Since a RAW subject image is represented by CCD-RAW data that has not been subjected to signal processing such as gamma correction, the detection accuracy of a face image is not necessarily high.

  The RAW subject image shown in FIG. 4 includes human subject images 41, 42, and 43. As described above for the RAW subject image, face image extraction processing is performed by the face extraction circuit 26, whereby the face images i51 and i52 surrounded by the detection frames F51 and F52 are extracted (detected). Information (face information) about the face image is obtained by the face image extraction process. Since it cannot be said that the accuracy of the face image extraction process in the RAW subject image is high, the face image for the human subject image 43 is not detected.

  FIG. 5 is an example of face information (RAW face information) obtained by performing face image extraction processing on a RAW subject image.

  The RAW face information includes the position, size, orientation, inclination, and score (value representing the likelihood of a face image) of the detected face image. The face information is calculated corresponding to the detected face images i51 and i52.

  FIG. 6 is an example of a YC subject image.

  The subject image represented by the YC data obtained as described above is referred to as a YC subject image. Unlike the RAW subject image, the YC subject image is represented by YC data that has undergone signal processing such as gamma correction, and thus the detection accuracy of the face image is relatively high.

  The YC subject image shown in FIG. 6 includes human subject images 41, 42, and 43, similarly to the RAW subject image shown in FIG. As described above, the face image extraction process is performed on the YC subject image by the face extraction circuit 26, thereby extracting the face images i61, i62, and i63 surrounded by the detection frames F61, F62, and F63. . Since the accuracy of the face image extraction process in the YC subject image is relatively high, the face image i63 for the person subject image 43 that is not detected in the RAW subject image is also extracted.

  FIG. 7 is an example of face information (YC face information) obtained by performing face image extraction processing on a YC subject image.

  The position, size, orientation, inclination, and score of the detected face image are also included in the YC face information. Since the face image i63 of the person image 43 is also extracted from the YC subject image, face information corresponding to the face image i63 is calculated in addition to the face images i61 and i62.

  FIG. 8 is a flowchart showing an imaging processing procedure.

  When the imaging mode is set, the subject is imaged as described above and CCD-RAW data is obtained (step 51). A face image is extracted from the RAW subject image obtained by imaging (step 52).

  Further, signal processing such as generation of YC data and gamma correction is performed on the CCD-RAW data (step 53). A face image is extracted from the YC subject image obtained by the signal processing (step 54).

  Subsequently, using the face image (face information) extracted from the RAW subject image and the face image (face information) extracted from the YC subject image, erroneous detection suppression processing (step 55) and non-detection suppression processing (step 56). Is done. Details of these processes will be described later.

  In the erroneous detection suppression process and the non-detection suppression process, face information to be recorded on the memory card is determined from the RAW face information and the YC face information. The determined face information is stored in the header of the image file (generated by the system control circuit 1) (step 57). The captured YC data is stored in the image data recording area of the image file. An image file storing face information and YC data is recorded on the memory card.

  Since face information is determined using the RAW subject image and the YC subject image, relatively accurate face information can be obtained. In the embodiment described above, both the erroneous detection suppression process and the non-detection suppression process are performed. However, it is more common that either one of the processes is performed.

  FIG. 9 is a flowchart showing the procedure of the erroneous detection suppression process (the process of step 55 in FIG. 8).

  This erroneous detection suppression process determines whether or not the face image i63 as detected in the YC subject image shown in FIG. 6 without being detected in the RAW subject image shown in FIG. 4 is erroneously detected.

  If the value obtained by multiplying the score for the face image detected in the YC subject image by the weighting factor (1> weighting factor> 0) is higher than the threshold used for the face extraction described above (YES in step 61). (If the threshold value used for face extraction is considered as the first threshold value, the score is greater than or equal to the second threshold value greater than the first threshold value). It is considered high and the reliability that the extracted face image is a face image is considered to be relatively high. Therefore, it is determined that the face image is not erroneously detected, and is registered as face information to be recorded on the memory card (step 70).

  If the value obtained by multiplying the score by the weight coefficient is lower than the threshold value (NO in step 61), a face image corresponding to the face image in the YC subject image having the score is found from the face image of the RAW subject image. (Steps 62 to 69).

  First, among the face images in the YC subject image, the size of the face image to be subjected to the false detection suppression process is compared with the size of any one of the face images in the RAW subject image (step 62). ). When the size difference is not more than a predetermined threshold value (YES in step 63), the face orientations are compared (step 64). If the difference in face orientation is also less than or equal to the predetermined threshold (YES in step 65), the face inclinations are compared (step 66). If the difference in inclination is also less than or equal to a predetermined threshold (YES in step 67), the distances between the face centers are compared (step 68). If the distance between the centers of the faces is equal to or less than the predetermined threshold (YES in step 69), it is considered that a face image corresponding to the face image detected in the YC subject image exists in the RAW subject image. It is determined that the face image detected in the image is not a false detection, and face information is registered (step 70). Such erroneous detection suppression processing is performed for all face images detected in the YC subject image.

  As shown in FIGS. 4 and 6, the face image of the person image 43 is detected in the YC subject image (face image i63) but not in the RAW subject image. In such a case, if the value obtained by multiplying the score of the face image i63 by the weighting coefficient is larger than the threshold value, the face image i63 is not erroneously detected, but the score of the face image i63 has a weighting coefficient. If the multiplied value is less than or equal to the threshold value, the corresponding face image is not detected in the RAW subject image, and the face image i63 is determined to be erroneously detected. In the face images i62 and i63 detected in the YC subject image, since the corresponding face images i52 and i53 exist in the RAW subject image, the face information is registered regardless of the score.

  10 and 11 are flowcharts showing the procedure of the undetected suppression process (step 56 in FIG. 8). In these drawings, the same processes as those shown in FIG.

  This non-detection suppression process is performed by converting the face information about the face image detected in the RAW subject image as YC face information when the detected face image in the RAW subject image shown in FIG. 4 is not detected in the YC subject image. To do. Further, even when the score of the face image detected in the RAW subject image is larger than the score of the face image detected in the YC subject image, the score of the face image detected in the RAW subject image is detected in the YC subject image. It is replaced with the score of the face image.

  If the value obtained by multiplying the score for the face image detected in the RAW subject image by the weighting factor (1> weighting factor> 0) is not higher than the threshold value used for the face extraction described above (YES in step 71) ) (If the threshold used for face extraction is considered as the first threshold, the score will be less than the second threshold greater than the first threshold), the score will be compared Therefore, the reliability that the extracted face image is a face image is considered to be relatively low. For this reason, the undetected suppression process is not performed on the face image.

  If the value obtained by multiplying the score by the weighting factor is higher than the threshold value used for face extraction (NO in step 71), undetected suppression processing is performed, and the RAW subject image is extracted as described above. A face image corresponding to the detected face image is found in the YC subject image (steps 62 to 69).

  When a face image corresponding to the face image extracted in the RAW subject image is found in the YC subject image, a face image is added to the image portion of the YC subject image corresponding to the face image (face information) extracted in the RAW subject image. Is present and a face image is detected (step 72). For example, when the face image i62 shown in FIG. 6 is not detected and the score of the face image i52 shown in FIG. 4 is high, it is determined that the face image exists in the portion corresponding to the face image i52 in the YC subject image. The

  The score for the face image detected in the RAW subject image and the score of the face image for the portion of the YC subject image that the face image is considered to be present (the face image score is stored in the memory 2) (Step 73). If the score for the face image detected in the RAW subject image is greater than the score of the face image for the portion of the YC subject image that the face image is considered to be present (YES in step 74), it is detected in the RAW subject image. The face information about the face image is stored in the YC face information as the face information of the face image for the portion of the YC subject image where the face image is considered to exist (step 75). If the score for the face image detected in the RAW subject image is not greater than the score of the face image for the portion of the YC subject image that the face image is considered to be present (NO in step 74), the process in step 75 is skipped. Is done.

  If a face image corresponding to one of the face images extracted from the RAW subject image is not found in the YC subject image (NO in step 63, 65, 67 or 69), the next face image is handled. Increment to find a facial image to be performed (step 76). The process of finding the corresponding image in the YC subject image is repeated for all the face images extracted in the RAW subject image (step 77). When the face image corresponding to the face image extracted from the RAW subject image is not included in the YC subject image, new face information is registered as the corresponding face image being included in the YC subject image ( Step 77).

  FIG. 12 is a flowchart showing an imaging process procedure according to another embodiment. In this figure, the same processes as those shown in FIG.

  When the shutter button is pressed (YES in step 50), actual imaging is performed and CCD-RAW data is obtained as described above (step 51A). Face image extraction processing is performed from the RAW subject image (step 52). Signal processing such as YC data generation processing is performed using the face image (RAW face information) extracted in the face image extraction processing (step 53A). For example, it is possible to realize signal processing that brightens the detected face image portion. Thereafter, face image extraction processing and the like are performed using the YC subject image obtained by signal processing (steps 54 to 58).

  Since the YC subject image subjected to the face image extraction processing is subjected to signal processing suitable for the face image so that the face image detected in the RAW subject image becomes bright, the face image in the YC subject image. The extraction process can also be executed relatively accurately.

  FIGS. 13A and 13B show still another embodiment. (A) is a flowchart showing an imaging process procedure, and (B) is a flowchart showing a reproduction process procedure.

  In this embodiment, RAW face information and YC data obtained by extracting a face image from a RAW subject image during recording are recorded in a memory card, and YC obtained by extracting a face image from a YC subject image during reproduction. It generates face information. The face information is updated from the RAW face information and the YC face information.

  Referring to FIG. 13A, when the imaging mode is set and the shutter button is pressed (YES in step 81), the main imaging is performed and CCD-RAW data is obtained (step 82). A face image is extracted from the RAW subject image to obtain RAW face information (step 83).

  Using the obtained RAW face information, signal processing including YC data generation is performed on the CCD-RAW data so that the face image portion has appropriate brightness and the like (step 84). Raw face information is stored in the header of the image file, and YC data is stored in the image data recording area of the image file (step 85). The image file is recorded on the memory card (step 86).

  Referring to FIG. 13B, when the reproduction mode is set, the image file recorded on the memory card is read (step 91). The YC data stored in the image file is given to the face extraction circuit 26 of the digital still camera, and a face image is extracted from the YC subject image represented by the YC data to obtain YC face information (step 92). ).

  The erroneous detection suppression process (step 93) and the non-detection suppression process (step 94) described above are performed from the raw face information and the YC face information recorded in the header of the image file read from the memory card. Thereafter, the face information is updated (the face information indicating the position where the face image portion is considered to be present is determined from the RAW face information and the YC face information) (step 95). Then, the YC data recorded in the image data recording area of the image file read from the memory card is reproduced and the YC subject image is displayed (step 96). When the YC subject image is displayed, a frame or the like can be displayed on the face image portion determined based on the updated face information. The displayed frame represents the face image portion relatively accurately.

  FIG. 14 shows still another embodiment and is a flowchart showing an imaging processing procedure.

  In this imaging process, two pieces of face information respectively obtained from a through image obtained by imaging a subject (pre-imaging, through-image imaging) and a RAW subject image obtained by main imaging are used before main imaging. , Final face information is determined.

  When the imaging mode is set, a subject is imaged at a fixed period, and CCD-RAW data of a through image is obtained (step 102). Since it is only necessary to be able to capture the subject when capturing a through image, the amount of CCD-RAW data obtained by capturing a through image should be smaller than the amount of CCD-RAW data obtained during actual imaging. , CCD 23 is controlled. A face image is extracted from the RAW through image represented by the CCD-RAW data of the through image to obtain face information (step 102).

  When the shutter button is pressed (YES in step 103), the main imaging is performed and CCD-RAW data having a data amount larger than the data amount of the CCD-RAW data of the through image is obtained (step 104). A face image is extracted from the RAW subject image of the main imaging, and RAW face information is obtained (step 105). Since the data amount of the RAW subject image of the main imaging is larger than the data amount of the RAW through image, the face image extraction process becomes relatively accurate. It can be said that the relationship between the RAW subject image and the RAW through image is the relationship between the YC subject image and the RAW subject image described above.

  The false detection suppression process (step 106) and the non-detection suppression process (step 107) described above are performed using the face information obtained from the RAW through image and the face information obtained from the RAW subject image of the main imaging. Final face information is determined from these processes. Signal processing including YC data generation and the like is performed on the CCD-RAW data obtained by the main imaging so that the face image portion represented by the determined face information has appropriate brightness and the like (step 108).

  Thereafter, the finally determined face information and the generated YC data are stored in an image file (step 109), and the image file is recorded on a memory card (step 110).

  15 to 19 (A) and 19 (B) show still another embodiment.

  In the above-described embodiment, the final face information is determined using the face information of the RAW through image obtained by capturing the through image and the face information of the RAW subject image obtained by the main image capturing. However, in this embodiment, final face information is determined using face information of a RAW through image obtained by capturing a through image and face information of a moving subject image obtained by capturing in a moving image mode. Is.

  The data amount of the RAW through image and the data amount of the moving subject image are both smaller than the data amount of the RAW subject image obtained by the main imaging, but the data amount of the moving subject image is larger than the data amount of the RAW through image. Many. For this reason, the accuracy of extracting a face image using a moving subject image is higher than the accuracy of extracting a face image using a RAW through image.

  FIG. 15 shows the size of the RAW through image. In this figure, so-called VI signal and HI signal, which are timing references for obtaining a RAW through image, are also shown.

  The RAW through image has 200 pixels in the horizontal direction and 190 lines in the vertical direction. The CCD 23 is controlled so that a RAW through image having such a size can be obtained. Of course, it is not limited to 200 pixels in the horizontal direction and 190 lines in the vertical direction.

  FIG. 16 shows the size of the moving subject image. In this figure, the VI signal and the HI signal are also shown.

  The moving image subject image (one frame image constituting the moving image) has 200 pixels in the horizontal direction and 380 lines in the vertical direction. The CCD 23 is controlled so that a moving image subject image having such a size can be obtained. Needless to say, the moving subject image is not limited to 200 pixels in the horizontal direction and 380 lines in the vertical direction. The size of the moving subject image may be larger than the size of the RAW through image and smaller than the size of the RAW subject image obtained by the main imaging.

  Face information is obtained by performing face image extraction processing on the RAW through image, and face information is obtained by performing face image extraction processing on the moving subject image. The final face information is determined from the two pieces of face information thus obtained.

  FIGS. 17A to 17C are examples of time charts showing the relationship between the CCD imaging control and the pressing of the shutter button. A two-stroke type shutter button is used.

  FIG. 17A is an example of a time chart of conventional imaging control.

  When the imaging mode is set, a through image is captured. When the shutter button is half-pressed at time t11, automatic exposure control is performed using the CCD-RAW data of the through image until time t12, and automatic exposure control is performed from time t12 to t13. . Thereafter, until the shutter button is fully pressed, the through image is repeatedly captured. When the shutter button is fully pressed at time t14, actual imaging is performed. Thus, conventionally, when the shutter button is pressed, the moving image mode is not driven.

  FIG. 17B is an example of a time chart of this embodiment.

  Until time t13, through image capturing, automatic exposure control, and automatic focusing control are performed as in the prior art. At time t13, the CCD is driven to the moving image mode. As described above, a moving image subject image having a data amount larger than the data amount of the RAW through image is obtained. Final face information is obtained from the face information obtained using the RAW through image and the face information obtained using the moving subject image.

  FIG. 17C is an example of a time chart of another embodiment.

  Until the shutter button is fully pressed at time t14, the through image is picked up, the automatic exposure control and the automatic focusing control are performed as in the conventional case, and the through image is picked up again. When the shutter button is fully pressed at time t14, it is driven to the moving image mode. Thereafter, the main imaging is performed from time t15.

  18A and 18B are examples of time charts. This embodiment shows processing when it is considered that half-pressing and full-pressing are performed almost simultaneously.

  FIG. 18A is an example of a conventional time chart.

  Until time t21, a through image is captured. When the shutter button is pressed at time t21, automatic exposure control is performed by time t22, and automatic focusing control is performed by time t23. Real imaging is started from time t24.

  FIG. 18B is an example of a time chart according to this embodiment.

  The through image capturing, automatic exposure control, and automatic focusing control are performed by time t23 as in the conventional case. When the time t23 comes, it is driven to the moving image mode. Real imaging is performed from time t24.

  FIG. 19 shows still another embodiment and is a flowchart showing an imaging processing procedure.

  In this processing procedure, the face information is determined by performing the false detection suppression process and the non-detection suppression process from the face information obtained from the RAW through image and the face information obtained from the RAW subject image obtained by the main imaging. A false detection suppression process and a non-detection suppression process are performed from the face information obtained from the image and the determined face information to determine final face information.

  When the imaging mode is set, the subject is imaged and RAW data of a through image is obtained (step 101). A face image is extracted from the RAW through image, and face information is obtained (step 102).

  When the shutter button is pressed (NO in step 103), actual imaging is performed and CCD-RAW data is obtained (step 104). A face image is extracted from the RAW subject image obtained by the main imaging, and temporary face information is obtained (step 105).

  A false detection suppression process (step 106) and a non-detection suppression process (step 107) are performed using the face information obtained from the RAW through image and the face information obtained from the RAW subject image in the main imaging. Signal processing including YC data generation processing is performed on the RAW data so that the face image portion based on the determined face information has appropriate brightness or the like (step 108).

  A face image is extracted from the YC subject image obtained by the signal processing, and YC face information is obtained (step 111). Using the YC face information and the temporary face information obtained as described above, the erroneous detection suppression process (step 112) and the non-detection suppression process (step 113) are performed again. As a result, final face information is determined and stored in the image file together with the YC data (step 114). Thereafter, the image file is recorded on the memory card (step 115).

  FIG. 20 shows still another embodiment and is a flowchart showing an imaging processing procedure.

  In this figure, the same processes as those shown in FIG. 19 are denoted by the same reference numerals and description thereof is omitted.

  In this embodiment, as described above, false detection suppression processing and non-detection suppression processing are performed from the face information obtained from the raw image RAW data and the face information obtained from the CCD-RAW data of the main imaging. Signal processing including generation of YC data is performed based on the provisional face information (steps 101 to 108). The temporary face information and YC data obtained in this way are stored in an image file (step 121) and recorded on a memory card (step 122).

  In the reproduction processing, as shown in FIG. 13B, final face information is determined from the temporary face information recorded on the memory card and the face information obtained from the YC data.

It is a block diagram which shows the electric constitution of a digital still camera. (A) to (C) are examples of face images. (A) to (C) are examples of face images. It is an example of a RAW subject image. It is an example of RAW face information. It is an example of a YC subject image. It is an example of YC face information. It is a flowchart which shows an imaging process procedure. It is a flowchart which shows a misdetection suppression process procedure. It is a flowchart which shows a part of undetected suppression process procedure. It is a flowchart which shows a part of undetected suppression process procedure. It is a flowchart which shows an imaging process procedure. (A) is a flowchart showing an imaging process procedure, and (B) is a flowchart showing a reproduction process procedure. It is a flowchart which shows an imaging process procedure. It is an example of a RAW through image. It is an example of the to-be-photographed object image. (A) to (C) are time charts showing imaging control. (A) and (B) are time charts showing imaging control. It is a flowchart which shows an imaging process procedure. It is a flowchart which shows an imaging process procedure.

Explanation of symbols

1 System control circuit
23 CCD
25 Image processing circuit
26 Face extraction circuit

Claims (17)

A solid-state electronic imaging device that images a subject and outputs color RAW data representing the subject image;
A signal processing circuit for performing predetermined signal processing including YC data generation on the color RAW data output from the solid-state electronic imaging device and outputting YC data;
First target image detection means for detecting a predetermined target image from a RAW subject image represented by color RAW data output from the solid-state electronic imaging device, and YC data output from the signal processing circuit Second target image detection means for detecting a predetermined target image from the YC subject image;
An imaging apparatus comprising:   The position of the predetermined target image in the subject image captured by the solid-state electronic imaging device from the target image detected by the first target image detection unit and the target image detected by the second target image detection unit. The imaging apparatus according to claim 1, further comprising first position determining means for determining. The second target image detecting means is
A predetermined target image having a target image quality equal to or higher than a first threshold value is detected from a YC subject image represented by YC data output from the signal processing circuit;
If the target image likelihood of the predetermined target image detected by the second target image detection means is equal to or higher than the second threshold value higher than the first threshold value, the target is equal to or higher than the second threshold value. The position of the predetermined target image having the image quality is determined as the position of the target image, and the second target image detection is performed when the target image quality of the detected predetermined target image is less than the second threshold value. A predetermined object having a target image quality less than the second threshold value in response to an image portion corresponding to the predetermined target image detected by the means being detected by the first target image detecting means; A second position determining means for determining the position of the image as the position of the target image;
The imaging device according to claim 1. The first target image detecting means is
Detecting a predetermined target image having a target image-likeness equal to or higher than a first threshold value from a RAW subject image represented by color RAW data output from the solid-state electronic imaging device;
The RAW subject image includes a predetermined target image having a target image likelihood that is greater than or equal to a second threshold value that is greater than the first threshold value, and the target image likelihood of the target image of the RAW image is YC. A replacement means for replacing the position of the corresponding target image of the YC image with the position of the target image of the RAW image when the target image of the image is larger than the target image of the corresponding target image;
The imaging device according to claim 1. The first target image detecting means is
Detecting a predetermined target image having a target image-likeness equal to or higher than a first threshold value from a RAW subject image represented by color RAW data output from the solid-state electronic imaging device;
The second target image detecting means is
A predetermined target image having a target image quality equal to or higher than a second threshold value is detected from a YC subject image represented by YC data output from the signal processing circuit;
The target image corresponding to the predetermined target image detected in the RAW subject image represented by the color RAW data output from the solid-state electronic imaging device is added to the predetermined image portion detected by the second target image detection means. Registration means for registering the position of the corresponding target image when there is no
The imaging device according to claim 1, further comprising:   YC data output from the signal processing circuit, data indicating the position of the target image detected by the first target image detection means, and the position of the target image detected by the second target image detection means The image pickup apparatus according to claim 1, further comprising a recording control unit that records data on the recording medium in association with each other. A solid-state electronic imaging device that images a subject and outputs color RAW data representing the subject image;
First target image detection means for detecting a predetermined target image from a RAW subject image represented by color RAW data output from the solid-state electronic imaging device;
A signal processing circuit that performs predetermined signal processing including YC data generation from the color RAW data output from the solid-state electronic imaging device, and outputs YC data;
Recording control means for recording the YC data output from the signal processing circuit and the data indicating the position of the target image detected by the first target image detection means in association with each other on a recording medium;
Second target image detection means for reading YC data recorded on the recording medium and detecting a predetermined target image from a YC subject image represented by the read YC data; and target image recorded on the recording medium Position determining means for determining the position of the predetermined target image based on the data indicating the position of the predetermined target image and the data indicating the position of the predetermined target image detected by the second target image detecting means;
An imaging apparatus comprising: A solid-state electronic imaging device that images a subject and outputs image data representing the subject image;
Pre-imaging control means for imaging the subject based on the pre-imaging command and controlling the solid-state electronic imaging device so that the amount of output image data is reduced;
Based on the main imaging instruction, the subject is imaged, and the main imaging that controls the solid-state electronic imaging device so that the data amount of the output image data is larger than the data amount of the image data obtained in the pre-imaging control. Control means,
First target image detection means for detecting a predetermined target image from a pre-subject image represented by image data output from the solid-state electronic imaging device under the pre-imaging control;
Second target image detection means for detecting a predetermined target image from a main captured subject image represented by image data output from the solid-state electronic imaging device under the main imaging control;
Position determining means for determining the position of the target image based on the predetermined target image detected by the first target image detecting means and the predetermined target image detected by the second target image detecting means; and the position Recording control means for recording data indicating the position determined by the determining means and image data output from the solid-state electronic imaging device under the control of the imaging control means on a recording medium in association with each other;
An imaging apparatus comprising: The image data representing the subject image used for the detection process by the first target image detection means and the image data representing the subject image used for the detection process by the second target image detection means are color RAW data,
A signal processing circuit that performs predetermined signal processing including YC data generation on image data output from the solid-state electronic imaging device under the control of the imaging control unit, and outputs YC data, and the signal processing A third target image detecting means for detecting a predetermined target image from the subject image represented by the YC data output from the circuit;
The position determining means is
A predetermined target image detected by the first target image detection means, a predetermined target image detected by the second target image detection means, and a predetermined target detected by the third target image detection means The position of the target image is determined based on the image.
The imaging device according to claim 8. The image data representing the subject image used for the detection process by the first target image detection means and the image data representing the subject image used for the detection process by the second target image detection means are color RAW data,
A signal processing circuit that performs predetermined signal processing including YC data generation on the image data output from the solid-state electronic imaging device under the control of the imaging control unit, and outputs YC data;
The recording control means is
The data indicating the position determined by the position control means and the YC data output from the signal processing circuit are recorded in association with each other on a recording medium.
The imaging device according to claim 8. Third target image detecting means for reading YC data recorded on the recording medium and detecting a predetermined target image from a subject image represented by the read YC data, and for the target image recorded on the recording medium Position determining means for determining the position of the predetermined target image based on the data indicating the position and the data indicating the position of the predetermined target image detected by the second target image detecting means;
11. The imaging device according to claim 10, further comprising: A solid-state electronic imaging device that outputs image data representing a subject image by imaging the subject;
A through image capturing control means for controlling the solid-state electronic image capturing device so that a subject is imaged in accordance with the setting of the image capturing mode, and the data amount of the output image data is the data amount for the through image;
A moving image mode image pickup control means for controlling the solid-state electronic image pickup device so that a subject is imaged based on the moving image mode command and the data amount of the output image data is larger than the data amount for the through image;
First target image detecting means for detecting a predetermined target image from a subject image represented by image data output from the solid-state electronic imaging device under the through image capturing control, and the moving image mode imaging control. Second target image detection means for detecting a predetermined target image from a subject image represented by image data output from the solid-state electronic imaging device,
An imaging apparatus comprising:   13. The imaging apparatus according to claim 12, wherein the image data is color RAW data. A solid-state electronic imaging device images a subject and outputs color RAW data representing the subject image,
A signal processing circuit performs predetermined signal processing including YC data generation on the color RAW data output from the solid-state electronic imaging device, and outputs YC data.
A first target image detecting unit detects a predetermined target image from a RAW subject image represented by the color RAW data output from the solid-state electronic imaging device;
A second target image detecting means detects a predetermined target image from the YC subject image represented by the YC data output from the signal processing circuit;
Control method of imaging apparatus. A solid-state electronic imaging device images a subject and outputs color RAW data representing the subject image,
A first target image detecting unit detects a predetermined target image from a RAW subject image represented by the color RAW data output from the solid-state electronic imaging device;
A signal processing circuit performs predetermined signal processing including YC data generation from the color RAW data output from the solid-state electronic imaging device, and outputs YC data.
The recording control means records the YC data output from the signal processing circuit and the data indicating the position of the target image detected by the first target image detecting means in association with each other on a recording medium,
A second target image detection unit reads the YC data recorded on the recording medium, detects a predetermined target image from the YC subject image represented by the read YC data,
Based on the data indicating the position of the target image recorded on the recording medium and the data indicating the position of the predetermined target image detected by the second target image detecting means, the position determining means Determine the position of
Control method of imaging apparatus. A solid-state electronic imaging device images a subject and outputs image data representing the subject image.
Pre-imaging control means images the subject based on the pre-imaging command, and controls the solid-state electronic imaging device so that the data amount of the output image data is reduced.
The solid-state electronic imaging unit picks up an image of the subject based on the main imaging command, and the amount of image data to be output is larger than the amount of image data obtained during pre-imaging control. Control the device,
A first target image detecting unit detects a predetermined target image from a pre-subject image represented by image data output from the solid-state electronic imaging device under the pre-imaging control;
A second target image detecting unit detects a predetermined target image from a main captured subject image represented by image data output from the solid-state electronic imaging device under the main imaging control;
A position determining unit that determines a position of the target image based on the predetermined target image detected by the first target image detecting unit and the predetermined target image detected by the second target image detecting unit;
Recording control means records the data indicating the position determined by the position determining means and the image data output from the solid-state electronic imaging device under the control of the imaging control means in association with each other on a recording medium;
Control method of imaging apparatus. The solid-state electronic imaging device outputs image data representing the subject image by imaging the subject,
The through image capturing control unit controls the solid-state electronic image capturing apparatus so that the subject is imaged in accordance with the setting of the imaging mode, and the data amount of the output image data becomes the data amount for the through image. ,
The moving image capturing control means images the subject based on the moving image mode command, and controls the solid-state electronic imaging device so that the data amount of the output image data is larger than the data amount for the through image,
A first target image detecting unit detects a predetermined target image from a subject image represented by image data output from the solid-state electronic imaging device under the through image capturing control;
A second target image detecting unit detects a predetermined target image from a subject image represented by image data output from the solid-state electronic imaging device under the moving image mode imaging control;
Control method of imaging apparatus.

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