JP2011120165A - Imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus with improved user's usability. <P>SOLUTION: A digital camera 10 performs a zoom process of moving an optical lens in response to a change in the optical zoom magnification, and at the same time, performs a predetermined process, i.e., an electrical directivity changing process, on a voice collected by microphones 5L and 5R, to enhance the directivity of a voice of a main subject 4, and causes an LCD 38 to display a directivity mark indicating the current directivity of the microphones 5L and 5R, whereby the user can recognize a change in the directivity of the microphones 5L and 5R, so that the degree of satisfaction of an operation performed by the user himself/herself can be improved. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image pickup apparatus that applies a predetermined process to collected sound according to an image pickup mode for picking up an image of a subject, particularly for sound emitted from a subject collected using a plurality of microphones.

An award-winning image pickup device is equipped with a function for picking up moving images, collecting sound around the image pickup device during moving image shooting, and recording the moving image and sound in synchronization. Has been.
Japanese Patent Application Laid-Open No. 5-333352 discloses a recording apparatus with a built-in recording device that can easily organize information by associating visualization information obtained by photographing with audio information related thereto. Has been. In particular, a recorder and a camera are built in the device body, and a unidirectional microphone is provided in the device body. The microphone is tiltable and rotatable with respect to the device, Necessary because the cursor is set at a position corresponding to the direction of the microphone, and the user operates the button for rotating the microphone to rotate the microphone and the cursor shows directivity according to the rotation of the microphone. The technique which can aim at the improvement of the sound collection efficiency of the audio | voice information to have been disclosed is disclosed.

  However, in the recording device built-in type imaging device of the prior art, the microphone has directivity and can be rotated, but a compact imaging that is convenient for carrying by a user such as a recent imaging device, especially a digital camera. If a structure in which a microphone having directivity is rotatable is adopted in the apparatus, the cost is increased and the imaging apparatus becomes large, which does not satisfy the specifications required for recent imaging apparatuses.

  Therefore, a digital camera that employs a plurality of microphones that can collect sound through a plurality of channels has been used award. Many users may consider a case where a moving image of a subject is captured by the digital camera and recorded by performing zoom processing for enlarging the subject. Then, the moving image and the sound are recorded as a moving image file in synchronization with the sound. Later, when playing back a moving image file, the main subject is displayed in a large size, and it is obvious that the main subject is attracting attention. In addition to being played back with audio from other sound sources, the user feels very uncomfortable.

  Therefore, when using a plurality of microphones that can collect sound through a plurality of channels and capturing a moving image of a subject that has been subjected to zoom processing, the sound emitted from the main subject can be heard well according to the zoom processing. It is desirable to control the directivity of voice. Further, according to the zoom process, by giving information indicating the directivity of the currently recorded voice to the user, the degree of recognition of the user's own operation is increased, and the satisfaction level by the operation is improved. It is desirable.

  The present invention solves the above-described problem, and uses a plurality of microphones that can collect sound with a plurality of channels to perform zoom processing when capturing a moving image of a subject that has been subjected to zoom processing. Accordingly, the directivity of the sound can be controlled so that the sound emitted from the main subject can be heard well, and information indicating the directivity of the currently recorded sound can be given to the user according to the zoom process. An imaging apparatus is provided.

  An image pickup apparatus according to a first aspect of the present invention is an image pickup unit that picks up an image of a subject and outputs an image signal, a plurality of microphones that collect sound through a plurality of channels, and a display control that outputs an image based on the image signal to a display unit. Obtained from a plurality of microphones, zoom processing control means for executing zoom processing in which an image output to the display means is enlarged and displayed, zoom magnification changing means for receiving a zoom magnification change instruction in zoom processing, and the like. Directivity control means for controlling the directivity of sound and directivity marks indicating the directivity of sound obtained from a plurality of microphones are superimposed on the video signal corresponding to the image so that they are displayed at predetermined positions on the display means. In accordance with the mark display means to display and the zoom magnification change instruction, the sound directivity and directivity mark obtained from a plurality of microphones are displayed. And a further allowed to change means.

  An image pickup apparatus according to a second invention is dependent on the first invention, and the directivity control means controls directivity by electrically controlling sound collected from a plurality of microphones. To do.

  The imaging device of the third invention is dependent on the imaging device of the first invention or the second invention, and the changing means is a subject to be enlarged when the zoom magnification change instruction is a change in the enlargement direction. The sensitivity of the sound obtained from the direction of the object is increased while the sensitivity of the sound obtained from the direction of the subject to be reduced is reduced when the zoom magnification change instruction is a change to the reduction direction. .

  According to the imaging apparatus of the present invention, when capturing a moving image of a subject that has been subjected to zoom processing using a plurality of microphones that can collect sound using a plurality of channels, the image is emitted from the subject according to the zoom processing. The directivity of the sound can be controlled so that the sound can be heard well, and information indicating the directivity of the currently recorded sound can be given to the user according to the zoom process.

It is an illustration figure which shows the positional relationship of the digital camera 10 concerning a present Example, and a sound source. It is a block diagram which shows a part of circuit structure of the digital camera 10 concerning a present Example. It is a block diagram which shows a part of circuit structure of the microphone audio | voice process part 42 which concerns on a present Example. It is a figure for demonstrating the method the direction determination part 102 which concerns on a present Example calculates the direction from which an audio | voice comes. It is an illustration figure which shows an example of the screen displayed on LCD38 which concerns on a present Example. It is an illustration figure which shows an example of the image of the directivity of the microphones 5L and 5R which concern on a present Example. It is a flowchart which shows a part of operation | movement of the digital camera 10 concerning a present Example. 6 is a lookup table showing an example of a relationship between an optical zoom magnification and a register value according to the present embodiment.

  Hereinafter, as an embodiment of an imaging apparatus of the present invention, a mode implemented in a digital camera will be specifically described with reference to the drawings.

  FIG. 1 shows a positional relationship in the form in which the digital camera 10 of the present embodiment captures the main subject 4 and the sound generated from the sound source P, the sound source Q, and the sound source R is collected. FIG.

  Using the microphones 5L and 5R included in the digital camera 10 of the present embodiment, the sound source P that generates sound from the main subject 4 located on the optical axis of the lens group 16 including the optical lens included in the digital camera 10, The sound source Q located on the left side of the optical axis of the lens group 16 that generates sound from other than the subject 4 and the sound source R located on the right side of the optical axis of the lens group 16 that generates sound from other than the main subject 4 The sound from each is collected by two channels (Lch, Rch).

  FIG. 2 shows a block diagram of the digital camera 10.

  The digital camera 10 includes a lens group 16 including an optical lens and a diaphragm (not shown), and an optical image of the main subject 4 passes through a lens group 16 and a diaphragm controlled by a motor driving unit (not shown) according to an instruction from the CPU 22. 18 is taken in. In this embodiment, the CMOS imager unit 18 is used as the image sensor. However, a CCD imager may be used.

  Then, a digital imaging signal for one frame is output from the CMOS imager unit 18 by a capture pulse provided by a timing generator (not shown) connected to the CPU 22. Here, the CMOS imager unit 18 amplifies the charge accumulated in each pixel, reads out the signal from each pixel as a signal, and performs correlated double sampling processing, gain adjustment, clamping processing on the signal. A / D conversion processing is performed. The digital image signal subjected to the processing has one of R, G, and B color signals for each pixel, and is temporarily stored in the SDRAM 32 via the bus 40 under the control of the CPU 22.

  The digital image signal once stored in the SDRAM 32 is input to the signal processing circuit 20 under the control of the CPU 22. The signal processing circuit 20 performs color separation processing on the input digital imaging signal, and further converts it into Y, U, and V signals by YUV conversion. The digital image signal converted by the signal processing circuit 20 is stored in the SDRAM 32 again via the bus 40. In the present embodiment, the processing from when the digital imaging signal output from the CMOS imager unit 18 described above is converted into a digital image signal by the signal processing circuit 20 and stored in the SDRAM 32 is defined as imaging processing.

  Further, the digital image signal stored in the SDRAM 32 is output to the LCD 38 through the super invoke circuit 44 when necessary under the control of the CPU 22. The LCD 38 includes an LCD driver (not shown). The LCD driver converts Y, U, and V signals into RGB signals, and causes the LCD 38 to display an image signal based on the digital image signal. In the present embodiment, a process until the digital image signal stored in the SDRAM 32 is displayed as an image signal on the LCD 38 is defined as a display process. In the present embodiment, an embodiment in which the LCD 38 is employed as a display device will be described, but a display device such as an organic EL may be employed.

  The operation unit 24 includes a mode selection button 24a, a still image capturing button 24b, a moving image capturing button 24c, a menu button 24d, a reproduction start button 24e, and a zoom button 24f. By operating the mode selection button 24a by the user, it is possible to select either the shooting mode or the playback mode provided in the digital camera 10.

  Now, when the shooting mode is selected by operating the mode selection button 24a, the above shooting process is repeatedly executed based on a predetermined resolution and frame rate, and the display process is sequentially executed. As a result, a through image is displayed on the LCD 38.

  When the user presses the still image capturing button 24b while the through image is displayed, the above-described imaging processing is executed based on the resolution for still image capturing. Then, the digital image signal stored in the SDRAM 32 obtained by executing the above-described imaging processing is input to the compression / decompression processing circuit 26 under the control of the CPU 22, subjected to JPEG compression processing, and again compressed and stopped. It is stored in the SDRAM 32 as image data.

  The external memory card control circuit 30 controlled by the CPU 22 stores the compressed still image data stored in the SDRAM 32 in the JPEG file structure (start marker, end marker, header information (including thumbnail image data) in the external memory card 36. ), Including a plurality of segments and still image data). A recording operation from a series of imaging processes for recording the still image file is defined as a still image imaging process. In this embodiment, an embodiment in which the external memory card 36 is employed as a recording medium will be described. However, an internal memory may be provided inside the digital camera 10.

  In addition, when the moving image capturing button 24c is pressed by the user while the through image is displayed, the above-described imaging processing is repeatedly executed based on the resolution and frame rate for moving image capturing. In addition, the CPU 22 controls the microphone sound control unit 42 to perform predetermined processing (to be described later) on the analog sound signals output from the microphones 5L and 5R, and sequentially outputs the digital sound signals to the compressed signal processing 26. Let Referring to FIG. 1, sounds from the sound source P, the sound source Q, and the sound source R are collected by the microphones 5L and 5R.

  At the same time, the digital image signal stored in the SDRAM 32 obtained by executing the above-described imaging process is sequentially input to the compression / decompression processing circuit 26 under the control of the CPU 22, and the digital audio signal and the digital image signal are processed. MPEG-4 compression processing is performed, and the compressed video / audio data is stored in the SDRAM 32 again.

  Then, the external memory card control circuit 30 controlled by the CPU 22 sequentially transfers the compressed moving image / audio data stored in the SDRAM 32 to the external memory card 36, thereby the MP4 file structure (header information (thumbnail image data)). (Including video data information and audio data information which are compressed moving image / sound data). A recording operation from a series of imaging processes for recording the moving image file is defined as a moving image imaging process. Note that the display process described above is sequentially executed during the moving image capturing process, whereby a real-time recorded image is displayed on the LCD 38.

  It should be noted that the CPU 22 controls a motor drive unit (not shown) and is included in the lens group 16 when the zoom button 24f is operated in a state where a through image is displayed or a real-time recorded image is displayed. Move the optical lens.

  As the operation mode of the zoom button 24f, there are a wide angle operation for moving the optical lens to the wide angle side and a telephoto operation for moving the optical lens to the telephoto side. When the telephoto operation is performed, it is based on the optical image of the main subject 4. The image is enlarged and displayed on the LCD 38 (hereinafter referred to as an enlargement process). When a wide-angle operation is performed, the main subject 4 is reduced and displayed on the LCD 38 (hereinafter referred to as a reduction process). The wide-angle operation is mainly performed when returning from the magnification magnified by the telephoto operation to the original magnification.

  In this embodiment, by operating the zoom button 24f, the magnification of the enlargement process (hereinafter referred to as optical zoom magnification) can be linearly changed from 1 to 5 times. A telephoto operation and a wide-angle operation are defined as an optical zoom operation, and the above-described process based on the optical zoom operation is defined as an imaging zoom process.

  In the present embodiment, when the above-mentioned telephoto operation is performed in a state where the moving image capturing process is being performed, the CPU 22 causes the sound source P, the sound source Q, and the sound sources P to be collected by the microphones 5L and 5R according to the optical zoom magnification. With respect to the sound from the sound source R, a process for increasing the sensitivity of the sound from the sound source P, that is, an electrical directivity changing process is executed by the microphone sound processing unit 42, and the digital sound signal subjected to the directivity changing process is processed. The compressed signal processing 26 is sequentially output. Then, as described above, the moving image file based on the digital image signal and the digital audio signal is recorded on the external memory card 36. Further, the CPU 22 causes the LCD 38 to display a directivity mark indicating the directivity of the microphones 5L and 5R subjected to the directivity changing process on the LCD 38 as a real-time recorded image by superimposing it on the digital image signal according to the optical zoom magnification.

  When the playback mode is selected by operating the mode selection button 24a and the playback start button 24e is pressed, the CPU 22 controls the external memory card control circuit 30 and is recorded in the external memory card 36. The header information of the latest still image file or moving image file is read out to determine whether it is a reproducible file, that is, whether the file is not broken, whether it is a JPEG format file or an MP4 format file. If the file is reproducible, the format of the file is analyzed, and the compressed still image data or the compressed moving image / audio data is temporarily stored in the SDRAM 32 and decompressed by the compression / decompression processing circuit 26. Thus, an image signal based on the digital decompressed image signal is displayed on the LCD 38. When playing back a moving image file, an image signal based on the digital expanded image signal is displayed on the LCD 38, and the digital expanded audio signal is output to the D / A conversion circuit 46 to be converted into an analog expanded audio signal to be converted into the speaker 48. To output.

  Next, the electrical directivity changing process described above will be described in detail with reference to FIGS.

  FIG. 3 is a block diagram showing an outline of the internal configuration of the microphone sound processing unit 42. The microphone sound processing unit 42 separates and extracts sounds from a plurality of sound sources collected by the microphones 5L and 5R (in FIG. 1, three sound sources, a sound source P, a sound source Q, and a sound source R) for each sound source. Then, the current optical zoom magnification notified from the CPU 22 is detected, and processing for increasing the sensitivity of the sound from the sound source P is performed on the sound from each sound source separated and extracted according to the optical zoom magnification. As a result of such processing, when the viewer reproduces and views the moving image file, the sound from the main subject 4 can be heard more clearly.

  This will be described in more detail with reference to FIG. In FIG. 3, the digital audio signals output from the ADCs 6L and 6R are signals in the time domain, and when the elapsed time from a certain reference time is t (t is an integer), the digital audio signal is a function of t. Can be expressed as Hereinafter, digital audio signals output from the ADCs 6L and 6R are referred to as an original signal Li (t) and an original signal Ri (t), respectively.

  FFT (Fast Fourier Transform) sections 101L and 101R respectively perform discrete Fourier transform on the original signals Li (t) and Ri (t) to generate a frequency spectrum. The frequency spectrum output from each of the FFT units 101L and 101R is obtained by converting a digital audio signal output as a signal in the time domain from each of the ADCs 6L and 6R into a signal in the frequency domain. Therefore, the frequency spectrum can be expressed as a function of the frequency f (f is a positive integer). Hereinafter, the frequency spectra output from the FFT units 101L and 101R are referred to as frequency spectra L (f) and R (f), respectively.

  In the digital camera 10 of this embodiment, the ADCs 6L and 6R each convert an analog audio signal into a digital audio signal at a sampling frequency of 48 kHz (kilohertz), for example. The digital camera 10 uses 1024 samples of the generated digital audio signal, that is, approximately 21.3 msec (1024 × 1/48 kHz) as one frame, and performs audio signal processing on the digital audio signal in units of this frame. .

  The FFT units 101L and 101R perform discrete Fourier transform on the digital audio signal in units of one frame. At this time, the frequency band of the digital audio signal is subdivided into M (M is an integer of 2 or more) at a sampling interval of Δf, and a frequency spectrum is calculated for each subdivided frequency band. Hereinafter, the subdivided frequency band is referred to as a subdivided band. For example, if the total frequency band of the digital audio signal is ΔF, the number M of subdivided bands is M = ΔF / Δf. Here, ideally, by narrowing the sample interval Δf, each of the subdivided bands can include only the component of the digital audio signal from one sound source. That is, the digital audio signal included in each subdivided band can be considered as a component of a digital audio signal based on audio generated from any one of a plurality of sound sources.

  Assuming that the plurality of subdivided bands are f0, f1, f2,..., Fm-1 (m is an integer of 1 or more), the frequency spectra L (f) and R (f) are subdivided bands f0, .., fm-1 (m is an integer of 1 or more). Hereinafter, the frequency spectrums of the subdivided bands constituting the frequency spectra L (f) and R (f) are denoted by L (f0), L (f1), L (f2),... L (fm-1), respectively. And R (f0), R (f1), R (f2),... R (fm-1).

  The direction determination unit 102 calculates the phase difference when the digital audio signal included in each subband reaches the microphones 5L and 5R from the frequency spectrum of each subband output from the FFT units 101L and 101R. Based on this phase difference, the arrival direction of the digital audio signal included in each subdivided band is determined.

  FIG. 4 is a diagram for explaining a method by which the direction determination unit 102 calculates the direction in which the audio signal arrives. Now, a two-dimensional coordinate plane is assumed with the X axis and Y axis orthogonal to each other as coordinate axes. The X axis and the Y axis are orthogonal at the origin O. With the origin O as a reference, the X-axis positive direction is the right side, the negative direction is the left side, the Y-axis positive direction is the front, and the negative direction is the rear. It is assumed that the microphones 5L and 5R are located at different positions on the X axis and are symmetrical with respect to the Y axis, and the distance between the two microphones is D. The distance D is about several mm, for example. Now, for example, a sound included in the subband of f0 Hz is emitted from the sound source H, and the incident angle when the sound arrives at the origin O is set to θ ( rad) (radians). At this time, the incident angle to the microphones 5L and 5R can also be approximated to θ (rad). If the phase difference when the sound reaches the microphones 5L and 5R is Δφ (rad), Δφ is calculated from the frequency spectra L (f0) and R (f0) output from the FFT units 101L and 101R, respectively. Can do.

  Specifically, if the real part of the frequency spectrum L (f0) calculated by the discrete Fourier transform is L_r (f0) and the imaginary part is L_i (f0), the phase φl of L (f0) is

Can be calculated.

  Similarly, if the real part of the frequency spectrum R (f0) is R_r (f0) and the imaginary part is R_i (f0), the phase φr of R (f0) is

Can be calculated.

  Here, since the phase difference Δφ can be calculated as Δφ = φr−φl, it can be calculated by the following equation (1).

  Further, if the sound speed is C (mm / sec) and the distance between the microphones 5L and 5R is D (mm), Δφ can also be calculated from the following equation (2).

Therefore, the incident angle θ can be calculated from the following equation (3) from the above equations (1) and (2).

  From the above, it is possible to calculate the incident angle θ, which is the direction in which the voice included in the subdivided band f0 Hz arrives. In this way, the direction determination unit 102 calculates the incident angle of sound included in all the subdivided bands. Hereinafter, the incident angle of sound included in the subdivided band is simply referred to as the incident angle of the subdivided band.

  In the present embodiment, the direction determination unit 102 outputs all sets to the zoom magnification determination unit 103 by combining the frequency spectrum of the subband of the frequency spectrum L (f) and the incident angle of the subband. Note that the frequency spectrum of the subband of the frequency spectrum R (f) and the incident angle of the subband may be output as a set.

  For example, the incident angles of the subdivided bands f0, f1, f2, f3, f4, f5, f6, f7, f8, and f9 are θ0, θ1, θ0, θ0, θ1, θ1, θ1, θ2, θ2, and θ2, respectively. Assuming that (rad), the direction determination unit 102 determines that (L (f0), θ0), (L (f1), θ1), (L (f2), θ0), (L (f3), θ0), (L (f4), θ1), (L (f5), θ1), (L (f6), θ1), (L (f7), θ2), (L (f8), θ2), (L (f9) , Θ2) is output to the zoom magnification determination unit 103.

  The zoom magnification determining unit 103 extracts the frequency spectrum of the subdivided band for each incident angle from the set of the frequency spectrum of the subdivided band output from the direction determining unit 102 and the incident angle of the subdivided band and combines them. And a synthesized frequency spectrum is generated. That is, a synthesized frequency spectrum is generated for each voice arrival direction. Hereinafter, the synthesized frequency spectrum generated by synthesizing the frequency spectrum of the subdivided band coming from the incident angle θ will be referred to as L (θ).

  For example, the zoom magnification determination unit 103 receives (L (f0), θ0), (L (f1), θ1), (L (f2), θ0), (L (f3), θ0)) from the direction determination unit 102. , (L (f4), θ1), (L (f5), θ1), (L (f6), θ1), (L (f7), θ2), (L (f8), θ2), (L (f9) ), Θ2), the frequency spectrum L (f0), L (f2), L (f3) of the subdivided band with the incident angle θ0 is extracted and synthesized to generate a synthesized frequency spectrum L (θ0). To do.

  Similarly, L (f1), L (f4), L (f5), and L (f6) are extracted and combined to obtain a combined frequency spectrum L (θ1) from the incident angle θ1. Further, L (f7), L (f8), and L (f9) are extracted and combined to obtain a combined frequency spectrum L (θ2) from the incident angle θ2.

  Here, it is assumed that the synthesized frequency spectrum is extracted by the method described above based on the sound from the sound source P, the sound source Q, and the sound source R shown in FIG. In this case, the synthesized frequency spectrum from the sound source P is L (θP), the synthesized frequency spectrum from the sound source Q is L (θQ), and the synthesized frequency spectrum from the sound source R is L (θR). Since the sound source P is located in the optical axis direction of the lens group 16 of the digital camera 10, θP≈90 °. Thus, the zoom magnification determination unit 103 can recognize that the sound source P is a sound source from the main subject 4. In addition, the zoom magnification determination unit 103 determines that the sound source Q is positioned in a direction shifted by an angle that is counterclockwise from the sound source P positioned in the optical axis direction of the lens group 16 of the digital camera 10, and the sound source R is the sound source P. It can be recognized that it is located in a direction that is shifted clockwise by a certain angle.

  The zoom magnification determination unit 103 notifies the gain adjustment unit 104 of the combined frequency spectrum L (θP), L (θQ), and L (θR). The CPU 22 determines a register value according to the zoom magnification, and notifies the gain adjustment unit 104 to set the register value of the register 104 a provided in the gain adjustment unit 104.

  The gain adjusting unit 104 amplifies the frequency spectrum L corresponding to the combined frequency spectrum L (θP) corresponding to the register value of the register 104a with the first amplification factor, and corresponds to the combined frequency spectrum L (θQ). The frequency spectrum L to be amplified is subjected to amplification processing at the second amplification factor, and the frequency spectrum L corresponding to the combined frequency spectrum L (θR) is subjected to amplification processing at the third amplification factor.

  This will be specifically described with reference to the directivity diagrams of the microphones 5L (Lch) and 5R (Rch) shown in FIGS. For example, when a zoom operation corresponding to an optical zoom magnification of 1 to 2.5 is performed, the first amplification factor, the second amplification factor, and the third amplification factor are as shown in FIG. The directivity of the microphone 5L is approximately 90 ° counterclockwise with the optical axis direction of the lens group 16 of the digital camera 10 as the central axis, and the directivity of the microphone 5R is the optical axis direction of the lens group 16 of the digital camera 10. Is set to an amplification factor of approximately 90 ° clockwise with the center axis of.

  When a zoom operation corresponding to an optical zoom magnification of 2.5 to 4 is performed, the first gain, the second gain, and the third gain are as shown in FIG. 6B. The directivity of the microphone 5L is approximately 60 ° counterclockwise about the optical axis direction of the lens group 16 of the digital camera 10, and the directivity of the microphone 5R is centered on the optical axis direction of the lens group 16 of the digital camera 10. The gain is set so that the axis is approximately 60 ° clockwise.

  When a zoom operation corresponding to an optical zoom magnification of 4 times or more is performed, the first amplification factor, the second amplification factor, and the third amplification factor are the directivity of the microphone 5L as shown in FIG. About 30 ° counterclockwise about the optical axis direction of the lens group 16 of the digital camera 10 as a central axis, and directivity of the microphone 5R is about clockwise about the optical axis direction of the lens group 16 of the digital camera 10 as a central axis. The amplification factor is set to be 30 °.

  IFFT (Inverse Fast Fourier Transform) sections 105L and 105R perform inverse Fourier transform on the gain-adjusted frequency spectra L (f) and R (f), respectively, to convert them into signals in the time domain, respectively Lo (t ) And Ro (t).

  Although an example of the directivity changing process has been described above, the directivity may be changed by another method.

  Further, in the digital camera 10 of the present embodiment, when the electric directivity changing process is performed according to the change of the optical zoom magnification as described above, which directivity of the microphones 5L and 5R is determined with respect to the user. It can be shown to the user whether or not it has been changed. Specifically, the CPU 22 controls the super invoke circuit 44 to superimpose directivity marks representing the directivities of the microphones 5L and 5R on the digital image signal and output the images to the LCD 38 as a real-time recorded image. More specifically, when the CPU 22 detects the current optical zoom magnification, the CPU 22 determines a register value with reference to a lookup table showing the relationship between the optical zoom magnification and the register value as shown in FIG. A register value is set in a register 44 a provided in the circuit 44. The super invoke circuit 44 performs directional mark superimposition processing corresponding to the register value of the register 44 a to superimpose a directional mark on the digital image signal, and outputs the result to the bus 40.

  5A to 5C show real-time recorded image screens in which directivity marks displayed on the LCD 38 are superimposed on the digital image signal in accordance with the change in the optical zoom magnification.

  FIG. 5A shows a real-time recorded image screen displayed on the LCD 38 when the optical zoom magnification is 1, and the directivity of the microphones 5L and 5R as shown in FIG. A directivity mark 200 that makes an image appear on the image is superimposed on the digital image signal.

  FIG. 5B shows a real-time recorded image screen displayed on the LCD 38 when the optical zoom magnification is 3 times. The directivity of the microphones 5L and 5R as shown in FIG. A directivity mark 300 that makes an image appear on the image is superimposed on the digital image signal.

  FIG. 5C shows a screen of a real-time recorded image displayed on the LCD 38 when the optical zoom magnification is 5. The directivity of the microphones 5L and 5R as shown in FIG. Is superimposed on the digital image signal.

  FIG. 7 is a flowchart illustrating an example of the flow of directivity change processing and directivity mark superimposition processing. The directivity changing process and the directivity mark superimposing process are processes realized by the CPU 22 executing a program stored in a flash memory (not shown).

  First, when the mode selection button 24a of the digital camera 10 is operated to shift to the moving image capturing mode, the CPU 22 detects the optical zoom magnification in step S1. Next, the process proceeds to step S3. In step S3, a register value corresponding to the optical zoom magnification is determined using the lookup table shown in FIG. Next, the process proceeds to step S5. In step S5, the register value of the register 104a provided in the gain adjusting unit 104a in the microphone sound processing unit 42 and the register value of the register 44a provided in the super invoking circuit 44 are determined. Set the value to Next, the process proceeds to step S7, where it is determined whether or not there is an instruction to change the optical zoom magnification. If NO is determined, the process returns to step S7, and the determination is repeated until YES is determined. If YES is determined in the step S7, the process returns to the step S1 to repeat the above process.

  As described above, the digital camera 10 according to the present embodiment executes the zoom process for moving the optical lens according to the change in the optical zoom magnification, and at the same time, the sound collected by the microphones 5L and 5R. By performing predetermined processing, that is, electrical directivity changing processing, the directivity mark indicating the directivity of the current microphones 5L and 5R is displayed on the LCD 38 by strengthening the sound directivity of the main subject 4. Thus, the user can recognize the change in the directivity of the microphones 5L and 5R, and the user can further increase the satisfaction level of his / her own operation.

  In this embodiment, the CPU 22 executes the directivity changing process and the directivity mark superimposing process in accordance with the change in the optical zoom magnification. However, the CPU 22 may execute the process in accordance with the change in the electronic zoom magnification.

  Further, in this embodiment, the directivity changing process and the directivity mark superimposing process are executed in accordance with the change of the optical zoom magnification while the moving image capturing process is being executed, but the through image is being displayed. In this case, the directivity mark may be displayed on the LCD 38 by executing this process even when the optical zoom magnification is changed.

5L ... Microphone 5R ... Microphone 10 ... Digital camera 16 ... Lens group 18 ... CMOS imager unit 20 ... Signal processing circuit 22 ... CPU
24 ... Operation unit 30 ... External memory card control circuit 32 ... SDRAM
36 ... External memory card 38 ... LCD
42... Microphone audio processing unit 44... Superinvoce circuit 46... D / A conversion circuit 48.

Claims (3)

Imaging means for imaging a subject and outputting an image signal;
Multiple microphones that collect audio on multiple channels;
Display control means for causing the display means to output an image based on the image signal;
Zoom processing control means for executing zoom processing in which an image output to the display means is enlarged and displayed;
Zoom magnification changing means for accepting a zoom magnification change instruction in the zoom processing;
Directivity control means for controlling the directivity of sound obtained from the plurality of microphones;
Mark display means for superimposing and displaying on a video signal corresponding to the image so that a directivity mark indicating the directivity of sound obtained from the plurality of microphones is displayed at a predetermined position of the display means;
An imaging apparatus comprising: a changing unit that changes the directivity of the sound obtained from the plurality of microphones and the directivity mark in response to an instruction to change the zoom magnification.   The imaging apparatus according to claim 1, wherein the directivity control unit controls the directivity by electrically controlling sound collected from the plurality of microphones.   When the zoom magnification change instruction is a change in the enlargement direction, the changing means increases the sensitivity of the sound obtained from the direction of the subject to be enlarged, while the zoom magnification change instruction is in the reduction direction. The imaging apparatus according to claim 1, wherein the sensitivity of the sound obtained from the direction of the subject to be reduced is lowered.