JP2005176015A - Imaging apparatus and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image pickup apparatus and method for preventing noise from being generated by a zoom operation when shooting in a quiet place.
An imaging apparatus having a normal mode in which an imaging lens having a zoom mechanism for imaging a subject is driven at a predetermined speed and a silent mode in which a sound generated during zooming is quieter than the normal mode. An imaging device comprising: a measurement unit that measures a surrounding sound pressure or light amount at the time of photographing; and a control unit that sets either the normal mode or the silent mode based on a measurement result of the measurement unit Providing equipment.
[Selection] Figure 1

Description

  The present invention generally relates to an imaging apparatus, and more particularly to an imaging apparatus having a zoom function.

2. Description of the Related Art Conventionally, some imaging devices include a zoom mechanism that optically zooms an object in an imaging lens group that captures an image. This zoom mechanism is generally configured to operate with a drive motor as power. Yes. In such an imaging apparatus, a driving sound and a vibration sound (noise) are generated by operating a driving motor by a zooming operation. In an imaging device such as a video camera having a recording function, noise is recorded especially when shooting in a quiet place. Even in an imaging device that does not have a recording function, when shooting in a place where quietness is required Such noise is unsuitable. As a means to avoid this problem, refrain from zooming when the surroundings are quiet, control the voltage of the motor that operates the zoom mechanism to reduce the number of rotations, reduce the noise, or change the optical zoom to electronic zoom Can be considered. For example, Patent Documents 1 and 2 are known as conventional techniques.
JP-A-5-2125 JP 2003-348434 A

  However, it is troublesome to perform an operation that requires user confidence, and an erroneous operation is caused.

  Therefore, an object of the present invention is to provide an image pickup apparatus and method that prevent noise from being generated by a zoom operation when shooting is performed in a place where the periphery is quiet.

  An imaging apparatus according to one aspect of the present invention includes a normal mode in which an imaging lens including a zoom mechanism that captures an image of a subject is driven at a predetermined speed, and a silent mode in which sound generated during zooming is quieter than in the normal mode. A measurement unit that measures a sound pressure or a light amount of surroundings at the time of shooting, and a control unit that sets either the normal mode or the silent mode based on a measurement result of the measurement unit. It is characterized by having.

  A measuring apparatus according to another aspect of the present invention includes a normal mode in which an imaging lens having a zoom mechanism for imaging a subject is driven at a predetermined speed, and a silent mode in which sound generated during zooming is quieter than the normal mode. An imaging device having a first mode for photographing the subject at a first illuminance and a second mode for photographing the subject at a second illuminance lower than the first illuminance. And a control unit that sets the silent mode when the second mode is set.

  The imaging apparatus further includes a drive motor that drives the zoom mechanism, and an electronic zoom unit that electronically zooms data corresponding to an optical image captured by the imaging lens, and the silent mode is the drive motor. The zooming may be performed only by the electronic zoom means. Alternatively, in the silent mode, the optical zoom by the drive motor may be decelerated, and further, the electronic zoom means may be used in combination.

  The imaging apparatus may further include a display unit that displays an image by the imaging lens and the fact that the silent mode is set.

  An imaging method according to another aspect of the present invention includes a normal mode in which an imaging lens having a zoom mechanism for imaging a subject is driven at a predetermined speed, and a silent mode in which sound generated during zooming is quieter than the normal mode. A step of acquiring information relating to the volume of ambient sound at the time of shooting, and a step of setting either the normal mode or the silent mode based on the information It is characterized by having. The information regarding the loudness includes, for example, at least one of a sound pressure, a light amount, and a shooting mode set for the light amount. The setting step may set the silent mode if the information is smaller than a set value. When the setting step selects the silent mode, the imaging lens is driven at a speed lower than the predetermined speed, and the magnification for electronically zooming the optical image taken by the imaging lens is controlled to perform the imaging. And a step of supplementing the amount of deceleration of the optical zoom by the lens.

  Further objects and other features of the present invention will become apparent from the preferred embodiments described below with reference to the accompanying drawings.

  According to the present invention, it is possible to provide an imaging apparatus and method that prevent noise from being generated by a zoom operation when shooting is performed in a place where the periphery is quiet.

  Hereinafter, an imaging device (video camera) 100 according to a first embodiment of the present invention will be described with reference to the accompanying drawings. Here, FIG. 1 is a schematic block diagram of the video camera 100.

  First, generation of an imaging signal will be described. In FIG. 1, a lens unit 101 includes a lens, a zoom mechanism, an iris, and the like, and guides subject light to the imaging unit 102. The zoom motor 104 is controlled by a control signal supplied from the optical zoom control unit 105 and operates the zoom mechanism. The imaging unit 102 images a subject using a CCD, converts the obtained subject light into an electrical signal, and outputs the electrical signal to the camera signal processing unit 103. The camera signal processing unit 103 is a well-known method for converting a signal output from the imaging unit 102 into a video signal based on a television signal, such as A / D conversion, clamping, γ correction, and white balance. Processing is performed and output to the video signal processing unit 107.

  The video signal processing unit 107 compresses the information amount of the video signal from the camera signal processing unit 103 by using known block coding such as DCT and variable length coding, and the compressed video signal is stored in the recording unit 109. The video signal before being compressed is output to the display unit 110. The recording unit 109 performs necessary processing for recording, such as synchronization, addition of ID, etc., error correction coding, etc., on the video signal compressed by the video signal processing unit 107, and changes to a form suitable for recording. Record on media.

  The display unit 110 is supplied with an uncompressed analog signal that can be monitored from the video signal processing unit 107 and can monitor the image. In this embodiment, a video signal is output from the camera signal processing unit 103 to the display unit 110 via the video signal processing unit 107. However, a video signal input to the display unit 110 is output from the video signal processing unit 107. It is also possible to input directly after the D / A conversion from the camera signal processing unit 103 without going through.

  The video signal thus recorded is reproduced by the recording unit 109 in the reproduction mode, subjected to processing such as error correction, and then output to the video signal processing unit 107. The video signal processing unit 107 performs processing such as inverse DCT and variable length code decoding on the reproduction signal, and outputs it to the display unit 110.

  Next, generation of an audio signal will be described. The microphone unit 111 collects sound and outputs the obtained sound to the microphone amplifier 112. The microphone amplifier 112 amplifies the audio signal collected by the microphone unit 111 and outputs it to the audio signal processing unit 115. The audio signal processing unit 115 performs known processing such as A / D conversion and shuffling on the audio signal input from the microphone amplifier 112 and outputs the processed signal to the recording unit 109. The recording unit 109 performs processing such as error correction on the audio signal input from the audio signal processing unit 115 and records it on a recording medium. The audio signal thus recorded is reproduced by the recording unit 109 in the reproduction mode and output to the audio signal processing unit 115. The audio signal processing unit 115 performs processing reverse to recording, that is, deshuffling, D / A conversion, etc. on the playback signal, and then outputs the analog playback signal to the speaker 113, headphone jack (not shown), etc. To do.

  The zoom mechanism includes an optical zoom mechanism and an electronic zoom mechanism, and a normal mode and a silent mode described later are set by the system control unit 108. The normal mode is a mode in which an imaging lens having a zoom mechanism that captures an image of an object is driven at a normal speed (or without speed limitation), and the silent mode makes the sound generated during zooming quieter than the normal mode. Mode.

  The optical zoom mechanism includes a system control unit 108, an optical zoom control unit 105, a zoom motor 104, and a zoom mechanism of the lens unit 101. The system control unit 108 controls the optical zoom control unit 105. The optical zoom control unit 105 controls driving (speed) and stopping of the zoom motor 104. The zoom motor 104 is driven by, for example, moving the zoom mechanism (zoom lens) of the lens unit 101 in the optical axis direction.

  The electronic zoom mechanism includes a system control unit 108, an electronic zoom control unit 106, and a camera signal processing unit 103. The system control unit 108 controls the electronic zoom control unit 106. The camera signal processing unit 103 performs electronic zoom processing according to a control signal supplied from the electronic zoom control unit 106 under the control of the system control unit 108. The electronic zoom includes continuous magnification electronic zoom processing by linear interpolation.

  In the zoom mechanism, the system control unit 108 acquires information related to the volume of surrounding sounds. The information regarding the loudness includes at least one of a sound pressure, a light amount, and a shooting mode set for the light amount. A module that supplies such information to the system control unit 108 also constitutes the zoom mechanism of this embodiment. For example, the audio signal processing unit 115 measures the ambient sound pressure acquired by the microphone unit 111 and the microphone amplifier 112. The camera signal processing unit 103 measures the amount of light captured by the lens unit 101. The system control unit 108 has a memory (not shown), and the memory stores a set value (threshold value). The system control unit 108 has information about sound volume (sound pressure, light amount) that is smaller than a predetermined threshold value. For example, the silent mode is set, and the operation of the silent mode is commanded to the optical zoom control unit 105 and the electronic zoom control unit 106. The threshold value is calculated from actual experiments, simulations, and experience.

  Further, when the video camera 100 has a normal shooting mode for shooting the subject at a normal illuminance and a low-illuminance shooting mode for shooting the subject at a low illuminance, as will be described later. The selected shooting mode may be associated with the normal mode and the silent mode in zooming.

  The display unit 110 may display a zoom mode and a shooting mode, as will be described later, and the system control unit 108 can know zoom information input by the user via the operation unit 116.

  Next, a mode setting operation at the time of shooting by the video camera 100 will be described with reference to FIG. Here, FIG. 2 is a flowchart showing the mode selection process. First, the system control unit 108 determines whether or not it is a shooting mode (step S201). If the system control unit 108 determines that it is not in the shooting mode, the process ends. When the system control unit 108 determines that the shooting mode is set (step S201), the audio signal processing unit 115 calculates a temporal average value of the audio level signal input from the microphone unit 111 and starts measuring the sound pressure level. (Step S202). Next, the system control unit 108 determines whether or not the measured sound pressure level is a low sound pressure level (step S203). If the system control unit 108 determines that the sound pressure level is low (step S203), the operation sound generated by the zoom operation may be recorded as noise and may cause discomfort to surrounding people. Is set to a silent mode to be described later (step S204), and the process returns to step S201. On the other hand, when determining that the sound pressure level is not low (step S203), the system control unit 108 sets a normal mode that does not limit the optical zoom speed (step S205), and returns to step S201.

  Next, the silent mode set in step S204 will be described in detail with reference to FIGS. Here, FIG. 3 is a flowchart showing the operation in the silent mode. First, as shown in FIG. 4, the system control unit 108 displays a display 401 indicating that the silent mode (Silent Mode) is set on the display unit 110 that displays the captured video (step S <b> 301). Thereby, the user can confirm the zoom control mode.

  Next, the system control unit 108 notifies the optical zoom control unit 105 of the prohibition of optical zoom (step S302), and determines whether or not an optical zoom operation has been performed in the operation unit 116 (step S303). If the system control unit 108 determines that the optical zoom operation is not performed in the operation unit 116, the system control unit 108 ends the process. If the system control unit 108 determines that the operation is performed, the control signal supplied from the electronic zoom control unit 106 to the camera signal processing unit 103. Thus, the electronic zoom process is performed (step S304), and the process is terminated.

  Thus, in this embodiment, when the sound pressure is measured by the microphone unit 111 at the time of shooting and it is determined that shooting is performed in a place where the periphery is quiet, the zoom control is automatically set to the silent mode, Since the optical zoom operation is prohibited and electronic zoom processing is performed, it is possible to prevent the operation sound due to the zoom operation from being recorded as noise and the zoom operation sound from causing noise and discomfort to surrounding people. .

  Hereinafter, a modified example of the silent mode shown in FIG. 3 will be described with reference to FIGS. Here, FIG. 5 is a flowchart of a modification of the process shown in FIG. FIGS. 6A to 6C are graphs showing the relationship between time and zoom magnification in the overall zoom magnification, the optical zoom magnification, and the electronic zoom magnification, respectively. In this embodiment, the normal optical zoom speed is set to change from 1 to 20 times in 2 seconds.

  First, as shown in FIG. 4, the system control unit 108 displays a display 401 indicating that the silent mode (Silent Mode) is set on the display unit 110 that displays the captured video (step S501). Thereby, the user can confirm the zoom control mode.

  Next, the system control unit 108 determines whether or not an optical zoom operation has been performed on the operation unit 116 (step S502). If it is determined that the operation has not been performed, the process ends. On the other hand, if the system control unit 108 determines that the operation unit 116 has performed an optical zoom operation, the system control unit 108 instructs the optical zoom control unit 105 to operate at a zoom speed slower than the normal zoom speed (step S503). As a result, the optical zoom control unit 105 operates the optical zoom at a low zoom speed corresponding to ½ times the normal speed shown in FIG. Subsequently, the system control unit 108 instructs the electronic zoom control unit 106 to perform an electronic zoom process that compensates for the deceleration of the optical zoom speed (step S504). As a result, the electronic zoom control unit 106 changes the electronic zoom magnification as shown in FIG. As a result, as shown in FIG. 6A, the overall zoom magnification changes from 1 to 20 times in 2 seconds while keeping the zoom operation sound low, similarly to the normal optical zoom speed. In FIG. 6A, the magnification between 2 seconds and 4 seconds remains 20 times. However, as shown in FIG. 6C, the electronic zoom magnification gradually decreases, so the image quality by electronic zoom is reduced. Can be suppressed in a short time. The system control unit 108 ends the process after step S504.

  As described above, in the present embodiment, when the sound pressure is measured by the microphone unit 111 in the shooting mode and it is determined that the shooting is performed in a quiet place, the silent mode is automatically set and the optical zoom is performed. While reducing the speed and controlling the electronic zoom magnification to compensate for the slowdown of the optical zoom, the operation sound due to the zoom operation is recorded as noise while suppressing the image quality deterioration due to the electronic zoom, and to the surrounding people Noise and discomfort can be prevented.

  Hereinafter, a modification of the mode setting process shown in FIG. 2 will be described with reference to FIG. Here, FIG. 7 is a flowchart of a modification of the process shown in FIG. First, the system control unit 108 determines whether or not the shooting mode is set (step S701). If the system control unit 108 determines that the shooting mode is not set (step S701), the process ends.

  On the other hand, when the system control unit 108 determines that the shooting mode is set (step S701), the system control unit 108 instructs the camera signal processing unit 103 to measure the brightness of the subject (step S702). In response to this, the camera signal processing unit 103 calculates the average luminance of the entire screen by averaging the value obtained by converting the video signal into the luminance signal, and calculates the average luminance value and the aperture value at the time of shooting. The brightness of the subject is measured from the shutter speed value. It is determined whether or not the light amount level measured in step S702 is a low light amount level.

  Next, the system control unit 108 determines whether or not the measured light amount is lower than a set value (step S703). If the system control unit 108 determines that the amount of light is low (step S203), the operation sound generated by the zoom operation may be recorded as noise and may cause discomfort to surrounding people. The silent mode described with reference to FIG. 5 is set (step S704), and the process returns to step S701. On the other hand, if the system control unit 108 determines that the light level is not low (step S703), it sets a normal mode that does not limit the optical zoom speed (step S705), and returns to step S701. This is because there is a high probability that a quieter scene such as nighttime or indoors is desirable when the shooting environment is dark, and when it is bright, there is no problem with the sound generated by the video camera, such as outdoors in the daytime. This is based on the rule of thumb that the probability of

  As described above, in the present embodiment, the camera signal processing unit 103 performs light amount measurement in the shooting mode and automatically sets the zoom control to the silent mode. Therefore, there is a shooting environment in which a quiet zoom operation is desirable. It is possible to suppress the operation sound of the zoom operation when it is dark, and to record it as noise and to prevent noise and discomfort to the surrounding people.

  Hereinafter, still another modification of the mode setting process shown in FIG. 2 will be described with reference to FIG. Here, FIG. 8 is a flowchart of still another modification of the process shown in FIG. The video camera 100 of this embodiment is different from the other embodiments in that it includes a low light shooting mode suitable for low-illuminance shooting.

  First, the system control unit 108 determines whether it is a shooting mode (step S801). If the system control unit 108 determines that the shooting mode is not set (step S801), the process ends.

  On the other hand, when the system control unit 108 determines that the shooting mode is set (step S801), the system control unit 108 determines whether the shooting mode is a low-light shooting mode suitable for low-illuminance shooting (step S802). If the system control unit 108 determines that the low-light shooting mode is set (step S802), the operation sound generated by the zoom operation may be recorded as noise and may cause discomfort to surrounding people. Alternatively, the silent mode described with reference to FIG. 5 is set (step S803), and the process returns to step S801. On the other hand, when the system control unit 108 determines that the mode is not the low-light shooting mode (step S802), the system control unit 108 sets a normal mode that does not limit the optical zoom speed (step S804), and returns to step S801. This is based on an empirical rule that when the shooting mode is a low-light shooting mode suitable for low-light shooting, there is a high probability that a quieter scene such as nighttime or indoors is desirable.

  As described above, in this embodiment, it is determined whether or not a shooting mode such as a low-light shooting mode suitable for low-illuminance shooting in the shooting mode. If the shooting mode is suitable for low-light shooting, the zoom is automatically performed. Since the control is set to silent mode, the operation sound of the zoom operation is suppressed and recorded as noise when shooting at low illumination, where it is desirable that the zoom operation is quiet. It can prevent giving a pleasant feeling.

  As described above, according to the present invention, when shooting in a quiet place, it is possible to automatically control the optical zoom and the electronic zoom to suppress the operation sound due to the zoom operation. It is possible to prevent the operation sound caused by the zoom operation from being recorded as noise, and to prevent the operation sound of the zoom from causing discomfort to the people around.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various change and deformation | transformation are possible within the range of the summary. For example, the imaging apparatus of the present invention may be able to select a moving image recording mode with audio that simultaneously performs audio recording during moving image recording and a moving image recording mode without sound that does not perform audio recording during moving image recording.

1 is a schematic block diagram of an imaging apparatus according to an embodiment of the present invention. 3 is a flowchart for explaining mode selection in photographing by the imaging apparatus shown in FIG. 1. It is a flowchart for demonstrating the detail of the silence mode set with the flowchart of FIG. It is a figure which shows an example of the screen displayed on the display part of the imaging device shown in FIG. 1 with the flowchart shown in FIG. It is a modification of the flowchart shown in FIG. 6 is a graph showing the relationship between zoom magnification and time in the process shown in FIG. 5. It is a modification of the flowchart shown in FIG. It is another modification of the flowchart shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Imaging device 101 Lens part 103 Camera signal processing part 104 Zoom motor 105 Optical zoom control part 106 Electronic zoom control part 108 System control part 110 Display part 111 Microphone part 115 Audio signal processing part 116 Operation part

Claims (11)

An imaging apparatus having a normal mode in which an imaging lens having a zoom mechanism for imaging a subject is driven at a predetermined speed, and a silent mode in which sound generated during zooming is quieter than in the normal mode.
A measurement unit that measures the sound pressure of the surroundings during shooting,
An imaging apparatus comprising: a control unit that sets either the normal mode or the silent mode based on a measurement result of the measurement unit. An imaging apparatus having a normal mode in which an imaging lens having a zoom mechanism for imaging a subject is driven at a predetermined speed, and a silent mode in which sound generated during zooming is quieter than in the normal mode.
A measurement unit that measures the amount of light at the time of photographing obtained through the photographing lens;
An imaging apparatus comprising: a control unit that sets either the normal mode or the silent mode based on a measurement result of the measurement unit. A normal mode in which an imaging lens having a zoom mechanism for imaging a subject is driven at a predetermined speed, a silent mode in which a sound generated during zooming is quieter than the normal mode, and the subject is photographed at a first illuminance. An imaging device having a first mode for photographing and a second mode for photographing the subject at a second illuminance lower than the first illuminance,
An image pickup apparatus comprising: a control unit that sets the silent mode when the second mode is set. The imaging device
A drive motor for driving the zoom mechanism;
Electronic zoom means for electronically zooming data corresponding to the optical image captured by the imaging lens;
4. The image pickup apparatus according to claim 1, wherein the silent mode is zooming by prohibiting driving of the drive motor and only the electronic zoom unit. 5. The imaging apparatus further includes a drive motor that drives the zoom mechanism,
The imaging apparatus according to claim 1, wherein the silent mode decelerates an optical zoom by the drive motor. The imaging apparatus further includes electronic zoom means for electronically zooming data corresponding to the optical image captured by the imaging lens,
6. The image pickup apparatus according to claim 5, wherein the silent mode uses the electronic zoom means.   The imaging apparatus according to claim 1, further comprising a display unit that displays an image by the imaging lens and that the silent mode is set. This is an imaging method using an imaging device having a normal mode in which an imaging lens having a zoom mechanism for imaging a subject is driven at a predetermined speed and a silent mode in which the sound generated during zooming is quieter than in the normal mode. And
Obtaining information about the loudness of the surrounding sound at the time of shooting;
Setting either the normal mode or the silent mode based on the information.   9. The method according to claim 8, wherein the information about the loudness includes at least one of a sound pressure, a light amount, and a photographing mode set for the light amount.   The method according to claim 8 or 9, wherein the setting step sets the silent mode if the information is smaller than a set value.   When the setting step selects the silent mode, the imaging lens is driven at a speed lower than the predetermined speed, and the magnification for electronically zooming the optical image taken by the imaging lens is controlled to perform the imaging. The method according to claim 8, further comprising a step of compensating for a deceleration amount of the optical zoom by the lens.