JP2012124770A - Imaging apparatus having a plurality of subject detection means - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system for continuing a subject detection processing on a still image, obtaining an every V detection result and improving quality of a recording image of the still image since an image processing cannot be performed on the still image at a desired parameter in a case when a processing is stopped if a subject detection result cannot be obtained within prescribed time during simultaneous recording of the still image.SOLUTION: An imaging apparatus includes a plurality of subject detection circuits. When a moving image and a still image are simultaneously recorded, one of the plurality of subject detection circuits is used for subject detection of the still image. The other circuits are used for the subject detection processing of the moving image. Setting of the subject detection means to the moving image is changed and a sequence of the subject detection processing for the moving image is changed.

Description

  The present invention records video information input from an imaging means (sensor), such as a digital camera or a digital video camera, or audio information input from an audio input means on a recording medium of the digital camera or digital video camera, The present invention relates to a method for controlling subject detection means in an imaging apparatus capable of reading and reproducing video and audio information recorded on the recording medium from the recording medium.

  In order to improve the responsiveness of the subject detection process in the subject detection means in the imaging apparatus, the subject detection process is terminated when the detection result cannot be obtained during the simultaneous recording of the moving image still image.

  In addition, functional blocks are divided in advance for moving images and still images to reduce the processing load of the imaging apparatus, and optimal processing is performed on moving images and still images. (For example, refer to Patent Document 1).

JP 2009-60167 A

  However, in order to reduce the processing load on the imaging device, if the functional blocks are divided in advance for moving images and still images, the system of the imaging device becomes redundant, resulting in an increase in cost.

  Also, if the subject detection process is terminated, a detection result cannot be obtained, and optimal image processing cannot be performed with a desired parameter on a captured still image or moving image.

  FIG. 2A is a timing chart at the time of simultaneous recording of moving image still images in an imaging apparatus having a plurality of subject detection circuits.

  In the figure, VD is a vertical synchronization signal, and signal processing including subject detection processing in the imaging apparatus is executed in synchronization with the vertical synchronization signal. When there are four subject detection units (A to D in the figure), the detection result obtained by subject detection processing is 4VD after obtaining the detection images (X_0 to X_15) used in subject detection. Assume that the subject detection results (halftone dot portions X_0 to X_14 in the figure) are obtained later.

  However, when a still image is recorded during moving image recording, the timing for obtaining the subject detection result is further delayed. In the figure, it is assumed that the photographer has pressed the still image button at the timing (Trig.) Of VD3.

  In this case, among the four subject detection units, if the subject detection result (halftone dot X_3) in the subject detection unit D is not obtained after 4 VD, the subject detection process is terminated. As a result, the subject detection result is not obtained only for the detection image X_3 (the dotted line portion of the detection result in the figure).

  That is, only the subject detection result for the still image recorded image during moving image recording cannot be obtained.

  Further, when the subject detection process is continued without being aborted, as shown in FIG. 2B, for example, when a subject detection result is obtained after 8 VD, the detection result for the detection image X_3 is obtained with a delay. (The halftone dot part X_3 in the figure) During the processing of the subject detection part D, the subject detection result X_3 cannot be acquired at the timing that should be detected (the dotted line part 1 of the detection result in the figure).

  Further, since the detection process is continued, the detection process for the subject detection result X_7 is not performed. As a result, the subject detection result X_7 cannot be acquired (the dotted line portion 2 of the detection result in the figure).

  Therefore, the present invention continues without stopping subject detection processing for still images during simultaneous recording of moving image still images, acquires VD subject detection results for both moving images and still images, and does not impair subject detection processing for movies. It is an object of the present invention to provide a system capable of performing optimum image processing on a photographed still image with desired parameters and improving the quality of a recorded image of the still image.

  In order to achieve the above object, an imaging apparatus having subject detection means of the present invention includes a plurality of subject detection circuits, and in an imaging system that inputs the same image to all subject detection circuits, Subject detection circuits are allocated for moving images, and when recording still images for moving images, one of the multiple subject detection circuits is used for subject detection for still images, and the other is used for subject detection processing for moving images. Then, the setting of the subject detection means for the moving image is changed, the subject detection processing sequence for the moving image is changed, and the VD detection result can be obtained.

  According to the present invention, the subject detection process for the still image at the time of the simultaneous recording of the moving image still image is continued without being interrupted, the VD subject detection result is obtained for each of the moving image and the still image, and the subject detection processing for the movie is not impaired. Optimal image processing can be performed on the photographed still image with desired parameters to improve the quality of the recorded image of the still image.

It is a block diagram which shows schematic structure of imaging devices, such as a digital camera and a digital video camera, according to the first and second embodiments of the present invention. Timing chart of subject detection processing in a conventional imaging device Timing chart of subject detection processing in a conventional imaging device Timing chart of subject detection processing in imaging apparatus according to first and second embodiments of the present invention An example of a detection frame for subject detection in a conventional imaging device An example of a detection frame for subject detection according to the first embodiment of the present invention An example of a detection frame for subject detection according to the second embodiment of the present invention

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

(First embodiment)
FIG. 1 is a block diagram of an imaging apparatus such as a digital camera or a digital video camera having a plurality of subject detection units according to the first embodiment of the present invention.

[Example 1]
Hereinafter, the configuration of an imaging apparatus using a preferred embodiment of the present invention will be described with reference to the block diagram of FIG.

  In the figure, 101 is a focus lens, 102 is a solid-state image sensor such as a CMOS, and 103 is a sensor interface that executes A / D conversion processing for converting a signal read from the solid-state image sensor 102 such as a CMOS into a digital signal ( A sensor I / F) unit 104 processes a signal from the solid-state imaging device converted into a digital signal and generates image data. A camera signal processing unit 105 interlaces the image data to generate a high-definition still image. An IP conversion unit for converting a system signal to a progressive signal, 106 a moving image resizing unit for changing the image data to an angle of view for moving image recording, and 108 an NR (Noise Reduction) for the image resized by the moving image resizing unit 107 ) The processing unit 108 encodes the image data resized to the angle of view of the moving image. The moving image encoding unit 109 is a recording signal processing unit that converts a video signal and an audio information signal from a microphone (not shown) as audio information input means into a recording format, and further decodes audio data, An audio signal is sent to a speaker (not shown). Reference numeral 110 denotes a recording medium for recording video information and audio information.

  111 is a still image encoding unit that performs encoding processing such as JPEG, 112 is a still image recording medium such as an SD card that stores still image data encoded by still image encoding means such as JPEG, 113 Is a main memory such as an SDRAM for temporarily storing data processed by the functional blocks such as various signal processing units and encoding means, and the functional blocks share and use the main memory 113. In addition, signal processing data and image data are transferred via the main memory 113. Reference numeral 114 denotes an arbiter unit that controls access requests from the respective functional blocks to the main memory 113, and arbitrates access. 115 to 118 convert pixel data read from the solid-state imaging device 102 such as a CMOS into digital signals. A subject detection unit that detects a subject photographed in pixel data, 119 is a buffer unit that temporarily stores the subject detection results detected by the subject detection units 115 to 118, and 120 is a system control unit that controls the imaging apparatus. It is.

  In the present embodiment, what is detected by the subject detection units A to D (115 to 118) may be, for example, a “face” of the subject or another part.

  FIG. 3 shows a timing chart for simultaneous recording of moving image still images in the imaging apparatus.

  In the figure, VD is a vertical synchronization signal (hereinafter referred to as VD), and signal processing including subject detection processing in the imaging apparatus is executed in synchronization with the VD. In the figure, Trig. Is the timing when the photographer presses the still image button when recording a still image while recording a moving image.

  The Trig. Prior to the time (VD0-3 period), that is, during moving image recording, the subject detection result for the subject detection images X0-X2 is 4VD after the detection processing is executed based on the subject detection images X0-X2. The detection result (halftone dots X_0 to X_2) for the subject detection image is acquired later (VD4 to 6).

  When the photographer presses the still image button to record a still image, that is, in FIG. In response to an instruction from the system control unit 120 at this timing, the subject detection unit D (118) is dedicated to subject detection for still images. The other subject detection units A to C (115 to 117) are subject detection units for moving images.

  In addition, in response to an instruction from the system control unit 120, Trig. After this timing, the detection sequence in the subject detection units A to C (115 to 117) is changed so that the detection results can be obtained in a short cycle for the subject detection units A to C (115 to 117) for moving images.

  Here, the sequence is changed so that the detection result for the subject detection image can be acquired 3VD after the detection process is executed based on the subject detection image.

  In the subject detection process, as shown in FIG. 4, in the image used for subject detection, for example, a detection frame of 20 pixels × 20 pixels is used to discriminate the subject over the entire image used for detection.

  In order to obtain a subject detection result in a short cycle, the size of the detection frame is increased.

  For example, as shown in FIG. 5, a detection frame of 40 pixels × 40 pixels is used, and the detection frame is enlarged so that the subject is identified over the entire image used for detection. The subject can be identified in a short cycle.

  This sequence change is continued until the result of subject detection for a still image is obtained.

  In this embodiment, the detection process is executed based on the subject detection image X_3 for the still image, and then the detection result (halftone dot X_3) for the subject detection image is acquired 8VD (VD11) up to VD (VD11). After that, the detection sequence is restored after that (VD12 and later).

  That is, the detection sequence is changed so that the detection result can be obtained in a short cycle up to VD11.

  While the detection sequence is changed, the detection results (X_4 to X_10) are stored in the buffer 119 (gray portion in the figure).

  The subject detection result for the still image is interpolated by the detection result for the immediately preceding image (X_2 in the figure), and the detection result stored in the buffer 119 is changed while the other detection sequences are changed. Is interpolated with a delay of 1 VD (X_7 in the figure).

  By doing so, it is not necessary to perform the censoring process in the subject detection, and the subject detection result for the still image can be acquired. Based on the detection result, the camera signal processing unit 104 can optimize the optimum for the still image such as the optimum white balance. Image processing can be performed, and the quality of recorded images of still images can be improved.

  In addition, detection results that cannot be acquired during subject detection processing for still images can be acquired, and the subject detection results can be acquired for each VD period even in still image recording during moving image recording.

[Example 2]
In the first embodiment, as a means for changing the detection processing sequence in the subject detection unit assigned for moving images, the detection frame size in the subject detection image is changed, and detection results are obtained in a short cycle when simultaneously recording moving image still images. Although the configuration has been described, a configuration in which detection results are obtained in a short cycle using another method will be described here.

  In the block diagram of FIG. 1, when the photographer records a still image while recording a moving image, the system control unit 120 detects the timing of pressing the still image button, and subject detection units A to D ( 115 to 118), based on the history information of the detection results detected, the optimum parameter change is performed for the subject detection unit allocated for the moving image.

  For example, when a photographer records a still image while recording a moving image, the subject detection results acquired by the subject detection units A to D (115 to 118) before the timing of pressing the still image button (Trig. In FIG. 3) When the subject is concentrated near the center of the shooting angle of view in (history of VD 0 to 3 periods), as shown in FIG. 6, the position of the detection frame with respect to the subject detection unit assigned for moving images is concentrated near the center. .

  That is, in the subject detection image, the subject can be discriminated in a short cycle by performing subject detection processing only on the vicinity where the subject exists without discriminating the subject over the entire image.

  As described above, according to the imaging apparatus having a plurality of subject detection units of the present embodiment, when a moving image still image is simultaneously recorded, the processing is performed at the timing when the still image trigger is pressed with respect to a plurality of subject detection circuits. The subject detection circuit to be started is assigned for still images, the others are assigned for movies, the setting of the subject detection processing means for the movie is changed, and subject detection processing for movies is obtained until a subject detection result for still images is obtained. By changing the sequence, the subject detection processing is not aborted, so the detection result of the subject for the still image can be acquired, and the loss of the subject detection result that cannot be acquired when driving the subject detection unit for still images can be suppressed. During the subject detection process for a still image, it is possible to minimize a decrease in subject detection accuracy for a moving image.

DESCRIPTION OF SYMBOLS 101: Focus lens 102: Image pick-up element 103: Sensor I / F part 104: Camera signal process part 105: IP conversion part 106: Moving image resizing part 107: NR process part 108: Movie encoding part 109: Recording signal process part 110 : Recording medium 111: Still image encoding unit 112: Still image recording medium 113: Main memory 114: Memory control unit (access arbitration unit)
115-118: Subject detection unit 119: Buffer unit 120: System control unit

Claims (6)

The video information input from the imaging unit or the audio information input from the audio input unit, such as a digital camera or digital video camera, is recorded on the recording medium of the digital camera or digital video camera, and recorded on the recording medium. In an imaging apparatus that can read out and reproduce video and audio information from a recording medium and has a means for detecting a plurality of subjects and inputs the same image to all subject detection circuits, All of the subject detection circuits are allocated for moving images, and at the time of moving image still image simultaneous recording, one of the plurality of subject detection circuits is used for still image subject detection, and the other is used for moving images. An imaging apparatus having a plurality of subject detection means, characterized in that it is used for subject detection processing. 2. The assignment of a plurality of subject detection circuits during simultaneous recording of a moving image still image assigns a subject detection circuit whose processing is started when a still image trigger is pressed to a still image. An imaging apparatus having a plurality of subject detection means.   3. The apparatus according to claim 1, further comprising means for changing a setting of a subject detection processing unit for a moving image and changing a subject processing sequence of the subject detection processing unit during simultaneous recording of the moving image still image. An imaging apparatus having a plurality of subject detection means.   Means for monitoring the history of the subject detection result, and setting the parameters of the subject detection processing means allocated for the moving image based on the history information at a timing immediately before the still image trigger is pressed during moving image recording. An imaging apparatus comprising a plurality of subject detection means according to any one of claims 1 to 3. 5. An imaging apparatus having a plurality of subject detection means according to claim 4, wherein parameters of subject detection processing means assigned for moving images are set in accordance with the number of subjects present in the shooting angle of view. 5. The imaging apparatus having a plurality of subject detection means according to claim 4, wherein parameters of subject detection processing means assigned for moving images are set according to the position of the subject existing in the shooting angle of view.