JP2013207472A - Digital camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To record sound of a moving image suitable for a subject.SOLUTION: A digital camera includes: an imaging unit 12 for capturing a subject image; a sound collection unit 15 for collecting sound; a determination unit 14b for determining a subject to be imaged by the imaging unit 12; a change unit 14d for changing frequency characteristics of sound to be collected by the sound collection unit 15 on the basis of a determination result of the determination unit 14b; and a recording control unit 14 for recording sound whose frequency characteristics have been changed by the change unit 14d in a recording unit 20 as sound of a moving image captured by the imaging unit 12.

Description

  The present invention relates to a digital camera.

  There is known a digital camera that obtains moving image sound suitable for a shooting scene by changing the directivity of a microphone in accordance with a shooting scene set before shooting (see Patent Document 1).

JP 2002-199272 A

  When shooting a movie, the sound that the photographer wants to record differs depending on the subject. For example, if you are shooting a child, you may want to record the voice of the child. As in the prior art, changing the directivity of the microphone cannot cope with recording of sound suitable for the subject.

  A digital camera according to the present invention includes an imaging unit that captures a subject image, a sound collecting unit that collects sound, a determination unit that determines a subject to be captured by the imaging unit, and a frequency characteristic of sound collected by the sound collecting unit. A change unit that changes based on a determination result by the determination unit, and a recording control unit that records the sound whose frequency characteristics have been changed by the change unit in the recording unit as the sound of a moving image captured by the imaging unit. It is characterized by.

  According to the present invention, it is possible to record moving image sound suitable for a subject.

It is a figure which illustrates the structure of the digital camera by embodiment of this invention. It is a flowchart explaining the flow of imaging | photography process.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration example of a digital camera according to an embodiment of the present invention. In FIG. 1, the digital camera includes an imaging optical system 11, an imaging element 12, a frame buffer memory 13, a CPU 14, a microphone 15, and an operation member 16.

  The CPU 14 includes an image processing unit 14a, a scene determination unit 14b, a microphone amplifier 14c, a frequency characteristic changing unit 14d, and a video / audio encoding unit 14e.

  The imaging optical system 11 includes a plurality of lens groups including a zoom lens and a focusing lens, and forms a subject image on the light receiving surface of the imaging element 12. In order to simplify FIG. 1, the imaging optical system 11 is shown as a single lens.

  The image sensor 12 is configured by a CMOS image sensor or the like. The image sensor 12 photoelectrically converts the subject image to generate an image signal. The image signal is converted into a digital signal by an A / D converter (not shown) and temporarily stored in the frame buffer memory 13. The frame buffer memory 13 stores captured image signals, and is provided so that the stored image signals can be sequentially subjected to image processing and recording to the external memory 20.

  The CPU 14 controls the operation of the digital camera by executing a program stored in a flash memory (not shown). The image processing unit 14a performs various types of image processing (pixel interpolation processing, gradation conversion processing, contour enhancement processing, white balance adjustment processing, image compression processing, image expansion processing, etc.) on the image signal read from the frame buffer memory 13. Apply. The scene determination unit 14b performs a scene determination process for automatically determining a shooting scene while displaying a through image or shooting a moving image.

  The microphone amplifier 14c amplifies the audio signal collected by the microphone 15 and outputs it to the frequency characteristic changing unit 14d. The frequency characteristic changing unit 14d includes a high pass filter, a low pass filter, and a band pass filter. The frequency characteristic changing unit 14d changes the frequency characteristic of the audio signal output from the microphone amplifier 14c based on the determination result by the scene determining unit 14b (details will be described later).

  The video / audio encoding unit 14e receives the image signal after image processing output from the image processing unit 14a and the audio signal after frequency characteristic change output from the frequency characteristic changing unit 14d, respectively, from an external memory (for example, a memory card). ) Data encoding processing when recording in 20 is performed. The CPU 14 records the moving image file including the moving image data and the audio data on which the data encoding process has been performed in the external memory 20.

  The operation member 16 includes a release button (not shown), a moving image button, and the like. When each button is pressed, the operation member 16 sends an operation signal corresponding to each button to the CPU 14.

<Shooting process>
Since the present embodiment is characterized in that the frequency characteristics of the sound recorded at the time of moving image recording are changed according to the result of the scene determination process in the moving image shooting mode, the following description will be focused on this point. FIG. 2 is a flowchart for explaining the flow of photographing processing executed by the CPU 14. When starting the moving image shooting mode, the CPU 14 starts obtaining a through image and starts a program for executing the processing illustrated in FIG. Note that the through image is a monitor image repeatedly acquired at a predetermined frame rate by the image sensor 12 before a shooting instruction, and is displayed on an LCD monitor (not shown).

  In step S1 of FIG. 2, the scene determination processing unit 14b of the CPU 14 performs a scene determination process for determining a shooting scene at predetermined intervals (for example, several frames) based on the through image, and proceeds to step S2. Shooting scenes determined in this scene determination processing include, for example, a shooting scene “portrait” where the subject is a person, a shooting scene “child” where the subject is a child, and a shooting scene “landscape” where the subject is a landscape. is there. That is, in the scene determination process, the main subject is determined. In the present embodiment, when the shooting scene is not “portrait”, “child”, or “landscape”, the shooting scene is determined as “AUTO”. A known method is used as a method for determining a shooting scene. For example, the photographic scene is determined based on the focal length of the imaging optical system 11, the luminance information obtained from the through image, the result of face recognition processing on the through image, and the like.

  In step S2, the CPU 14 switches the shooting setting according to the scene determination result in step S1, and proceeds to step S3. In the present embodiment, shooting settings such as exposure setting, white balance setting, and AF (autofocus) setting are predetermined for each shooting scene so that an image suitable for the shooting scene can be obtained. For example, when the CPU 14 determines that the shooting scene is “child”, the CPU 14 switches the shooting setting so as to focus on the child's face recognized by the face recognition process.

  In step S3, the CPU 14 switches the frequency characteristic to be changed in the frequency characteristic changing unit 14d according to the scene determination result in step S1, and proceeds to step S4. In the present embodiment, the frequency characteristics of sound are predetermined for each shooting scene so that sound suitable for the shooting scene (subject) can be obtained.

  When the shooting scene is “child”, the frequency characteristic changing unit 14 d changes the frequency characteristic of the sound so as to emphasize the voice of the child. For example, only the upper and lower 300 Hz frequency bands are left around 1 kHz, which is a common child's voice frequency, and the other frequency bands are cut.

  When the shooting scene is “portrait”, the frequency characteristic changing unit 14d changes the frequency characteristic of the voice so as to emphasize the voice of the person. For example, only 0.15 to 13 kHz, which is a frequency band including a voice of a general person, is left, and other frequency bands are cut.

  When the shooting scene is “landscape”, the frequency characteristic changing unit 14d changes the frequency characteristic of the sound so as to cut the wind noise and the high frequency sound. For example, a general wind noise frequency band of 500 Hz or less and a high frequency sound of 15 kHz or more are cut. The reason why the high-frequency sound is cut is to remove high-frequency sound that cannot be heard by human ears and unnecessary noise.

  When the shooting scene is “AUTO”, the frequency characteristic changing unit 14d changes the frequency characteristic of the sound so that the frequency characteristic is uniform (flat).

  Here, since the live view is being displayed and the recording of the moving image and the sound has not started, no sound is collected by the microphone 15, but the frequency characteristic corresponding to the shooting scene is previously set in the frequency characteristic changing unit 14d. By switching to, voice recording can be started with frequency characteristics suitable for the shooting scene immediately after the start of moving image recording is instructed.

  In step S4, the CPU 14 determines whether or not the moving image button of the operation member 16 has been pressed. When the CPU 14 receives an operation signal from the moving image button, the CPU 14 recognizes that the start of moving image recording has been instructed, affirmative determination is made in step S4, and the process proceeds to step S5. When the CPU 14 does not receive the operation signal from the moving image button, the CPU 14 makes a negative determination in step S4 and returns to step S1.

  In step S5, the CPU 14 starts recording moving images and audio, and proceeds to step S6. Specifically, a moving image shot with the shooting setting switched in step S2 (that is, the shooting setting according to the shooting scene determined in step S1) is recorded. In addition, the audio signal collected by the microphone 15 is changed to the frequency characteristic switched in step S3 (that is, the frequency characteristic corresponding to the shooting scene determined in step S1) and recorded.

  In step S6, the scene determination unit 14b of the CPU 14 performs the scene determination process at predetermined intervals (for example, several frames) even during moving image recording, and the process proceeds to step S7.

  In step S7, the CPU 14 determines whether or not the shooting scene has changed. If the shooting scene determined in step S6 is different from the previously determined shooting scene, the CPU 14 makes a positive determination in step S7 and proceeds to step S8. On the other hand, if the shooting scene determined in step S6 is the same as the previously determined shooting scene, the CPU 14 makes a negative determination in step S7 and proceeds to step S10.

  In step S8, the CPU 14 switches the shooting setting according to the scene determination result in step S6, and proceeds to step S9. The switching of the shooting setting is the same as in step S2 described above. Thereafter, a moving image shot with shooting settings corresponding to the shooting scene determined in step S6 is recorded.

  In step S9, the CPU 14 switches the frequency characteristic according to the scene determination result in step S6 in the frequency characteristic changing unit 14d, and proceeds to step S10. The switching of the frequency characteristics is the same as in step S3 described above. Thereafter, the sound signal collected by the microphone 15 is recorded with the frequency characteristic changed according to the shooting scene determined in step S6.

  On the other hand, in the case of making a negative determination in step S7 and proceeding to step S10, the CPU 14 does not switch the moving image shooting setting and the frequency characteristic of the sound.

  In step S <b> 10, the CPU 14 determines whether or not the moving image button of the operation member 16 has been pressed. When receiving an operation signal from the moving image button, the CPU 14 recognizes that the end of recording of the moving image has been instructed, makes an affirmative decision in step S10, and proceeds to step S11. In step S11, the CPU 14 ends the recording of the moving image and the sound, and ends the process shown in FIG. On the other hand, when the CPU 14 does not receive the operation signal from the moving image button, the CPU 14 makes a negative determination in step S10 and returns to step S6.

According to the embodiment described above, the following operational effects can be obtained.
(1) The digital camera includes an imaging device 12 that captures a subject image, a microphone 15 that collects sound, a scene determination unit 14b that determines a subject that is captured by the imaging device 12, and a frequency of sound collected by the microphone 15. A frequency characteristic changing unit 14d that changes the characteristics based on a determination result by the scene determination unit 14b, and an audio in which the frequency characteristic is changed by the frequency characteristic changing unit 14d as audio of a moving image captured by the image sensor 12. 20 is recorded, so that the sound of a moving image suitable for the subject can be recorded.

(2) In the digital camera of (1), the scene determination unit 14b performs determination at predetermined intervals during moving image capturing, and the frequency characteristic change unit 14d sequentially changes the frequency characteristic of the sound based on the determination result. Thus, even if the subject changes during the moving image, the sound of the moving image can be made suitable for the subject.

(3) In the digital camera of (1) or (2) above, when the scene determination unit 14b determines that the subject is a person, the frequency characteristic change unit 14d converts the frequency characteristic of the sound into the voice of the person. Since the frequency characteristic is changed to the corresponding frequency characteristic, it is possible to record the voice that emphasizes the voice of the child together with the moving picture of the child.

(4) In the digital cameras of (1) to (3), when the scene determination unit 14b determines that the subject is a child, the frequency characteristic change unit 14d changes the frequency characteristic of the sound to a child's voice. Since the frequency characteristic is changed to the corresponding frequency characteristic, the voice in which the voice of the person is emphasized can be recorded together with the moving picture of the person.

(5) In the digital cameras of (1) to (4), when the scene determination unit 14b determines that the subject is a landscape, the frequency characteristic change unit 14d converts the sound frequency characteristics into wind noise. Since it is configured to change to a frequency characteristic to be reduced, it is possible to record a sound with reduced wind noise along with a landscape moving image.

(6) The digital camera of the above (1) to (5) further includes an operation member 16 for instructing start of moving image recording. In addition, since the audio frequency characteristic is changed based on the determination result by the scene determination unit 14b, the audio recording suitable for the subject can be started immediately after the start of recording the moving image is instructed. .

(Modification 1)
In the embodiment described above, it is determined in the scene determination process that the shooting scene is “child”, “portrait”, and “landscape”, but the present invention is not limited to this. For example, when the shooting scene is “portrait”, that is, when the subject is “person”, the sex may be further determined. When the subject is “male”, the frequency characteristic changing unit 14d of the first modification changes the frequency characteristic of the voice so as to emphasize a general male voice, and when the subject is “female”. Changes the frequency characteristics of speech to emphasize the general female voice.

(Modification 2)
When the shooting scene changes during moving image recording, the CPU 14 gradually changes the frequency characteristic changed by the frequency characteristic changing unit 14d from the current frequency characteristic to the frequency characteristic corresponding to the shooting scene determined in step S6. It may be. Thereby, it is possible to prevent the frequency characteristics of the audio of the moving image from changing abruptly between frames and giving the viewer a sense of discomfort during playback.

(Modification 3)
In the embodiment described above, the scene determination process is performed even during acquisition of a through image. However, the scene determination process is not necessarily performed during acquisition of a through image. For example, when recording of a moving image is instructed, the CPU 14 of Modification 3 performs the scene determination process based on the through image acquired immediately before, and switches the frequency characteristics of the sound to be recorded based on the determination result.

(Modification 4)
In the above-described embodiment, the frequency characteristic of the sound collected by the microphone 15 is changed by the frequency characteristic changing unit 14d. However, the present invention is not limited to this. For example, a plurality of microphones having different frequency characteristics may be provided, and the microphones to be used may be switched based on the scene determination result.

  The above description is merely an example, and is not limited to the configuration of the above embodiment. Moreover, you may combine the structure of each modification suitably with the said embodiment.

DESCRIPTION OF SYMBOLS 11 ... Imaging optical system 12 ... Imaging element 13 ... Frame buffer memory 14 ... CPU
14a ... Image processing unit 14b ... Scene determination unit 14c ... Microphone amplifier 14d ... Frequency characteristic changing unit 14e ... Video / audio encoding unit 15 ... Microphone 16 ... Operating member 20 ... External memory

Claims (6)

An imaging unit that captures a subject image;
A sound collecting section for collecting sound;
A determination unit for determining a subject to be imaged by the imaging unit;
A changing unit that changes a frequency characteristic of the sound collected by the sound collecting unit based on a determination result by the determining unit;
A recording control unit that records the sound whose frequency characteristics are changed by the changing unit in the recording unit as the sound of the moving image captured by the imaging unit;
A digital camera comprising: The digital camera according to claim 1, wherein
The determination unit performs the determination at predetermined intervals during imaging of the moving image,
The digital camera according to claim 1, wherein the changing unit sequentially changes a frequency characteristic of the sound based on the determination result. The digital camera according to claim 1 or 2,
When the determination unit determines that the subject is a person, the change unit changes the frequency characteristic of the sound to a frequency characteristic corresponding to a person's voice. The digital camera according to any one of claims 1 to 3,
When the determination unit determines that the subject is a child, the change unit changes the frequency characteristic of the sound to a frequency characteristic corresponding to a voice of a child. In the digital camera according to any one of claims 1 to 4,
The change unit changes the frequency characteristic of the sound to a frequency characteristic that reduces wind noise when the determination unit determines that the subject is a landscape. In the digital camera according to any one of claims 1 to 5,
An operation member for instructing to start recording a movie
The digital camera according to claim 1, wherein the changing unit changes the frequency characteristic of the audio based on the determination result before the operation member instructs to start recording the moving image.

Images