JP2010103668A - Moving image photographing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve such a problem that a moving image photographing apparatus such as a digital camera cannot photograph for a long period of time when the apparatus photographs with a removable memory card having a limited storage capacity or the like since the storage capacity shortly runs out. <P>SOLUTION: An image processing engine 1 detects a remaining photographing time capable of recording a moving image or a sound in the memory card 12 according to a remaining storage capacity of the memory card 12 or a battery remaining capacity of a battery when a photographer changes resolution of the image. The image processing engine 1 changes a sampling rate or a quantifying bit number of sound data to be recorded according to the kind of resolution (high resolution, medium resolution, low resolution) when the remaining photographing time capable of recording in the memory card 12 is detected to be a predetermined value or less. Accordingly, a size of the sound data to be recorded in the memory card 12 can be reduced according to the recording resolution of the moving image when the remaining photographing time capable of recording is short. Thus, the apparatus can keep photographing for a longer period of time. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a moving image photographing apparatus for recording a moving image picked up by an image pickup unit together with a sound collected by a sound collecting unit.

Conventionally, as this kind of moving image photographing apparatus, there is a digital camera disclosed in Patent Document 1, for example. In this digital camera, a recording scene file used for recording using the best shot function is stored in a program memory. Three scene files for recording are prepared as the best shot scenes for recording that are assumed in advance: concert recording, conference recording, and landscape recording. Each of these recording scene files is composed of recording setting information, various image setting information, and a scene ID. In the recording setting information, in concert recording, the bit rate target value is increased, the sampling frequency is 44.1 kHz, the tracking time setting is long, and the maximum amplification setting is low so that the sound quality is as high as possible. In the conference recording, it is preferable to record a voice of a distant person as much as possible. Therefore, the follow-up time setting is short and the maximum amplification setting is set high. Also, since landscape recording is recording outdoors, the filter setting value is set to ON.
JP 2006-217111 A (see paragraphs [0030] to [0034] and FIG. 2)

  The conventional digital camera disclosed in Patent Document 1 can perform sound recording suitable for the shooting environment by performing recording setting corresponding to the best shot scene for recording. However, a storage medium such as a memory card for recording recorded data has a limited storage capacity. For this reason, in order to save the storage capacity of a memory card or the like, for example, even if the recording resolution of a moving image shot in concert recording is reduced, the sound is recorded with high sound quality. I couldn't continue to shoot because the memory was almost gone.

The present invention has been made to solve such problems,
Storage means for recording a moving image picked up by the image pickup means together with sound collected by the sound collecting means, and resolution setting means for setting the resolution of the moving image recorded in the storage means to an arbitrary resolution from a plurality of types. In the video shooting device provided,
Detecting means for detecting a remaining shooting time in which a moving image and sound can be recorded in the storage means;
If the remaining shooting time detected by the detection means is less than or equal to a predetermined value, the sampling rate of the sound collected by the sound collection means and recorded in the storage means according to the type of resolution set by the resolution setting means And recording setting value changing means for changing each recording setting value of the number of quantization bits.

  According to this configuration, when the detection unit detects that the remaining shooting time that can be recorded in the storage unit is equal to or less than the predetermined value, the recording setting value changing unit changes the sampling rate and the number of quantization bits of the audio to be recorded. Each recording setting value is changed according to the type of resolution. For this reason, when the remaining recordable recording time is short, the data size of the sound recorded in the storage unit can be reduced according to the recording resolution of the moving image. As a result, the remaining shooting time that can be recorded in the storage means can be extended by reducing the audio data size, and shooting can be continued for a longer time.

  Further, the present invention is characterized in that the detection means detects the remaining storage capacity of the storage means or the remaining battery capacity of the battery that supplies driving power, and detects the remaining photographing time.

  According to this configuration, the remaining shooting time that can be recorded in the storage unit is detected by the remaining recording capacity of the storage unit or the remaining battery capacity of the battery.

  Further, the present invention is characterized in that the storage means can be attached to and detached from the moving image photographing apparatus.

  According to this configuration, even if the removable storage unit has a limited storage capacity, the recording setting value changing unit changes the sound recording setting value according to the recording resolution, so that the storage capacity is quickly lost. Without worrying about that, you can shoot longer.

  In addition, the present invention is characterized by comprising recording setting value setting means for setting each recording setting value to an arbitrary value.

  According to this configuration, it is possible to arbitrarily set each recording set value, that is, the sampling rate and the number of quantization bits of the sound to be recorded by the recording set value setting means. For this reason, for example, even if the recording resolution of the moving image is lowered, it is possible to record sound with high sound quality.

  According to the present invention, as described above, the audio data size recorded in the storage unit can be reduced in accordance with the resolution of the moving image, so the remaining shooting time that can be recorded in the storage unit is the audio data. The size can be extended by a smaller size, and shooting can be continued for a longer time.

  Next, the best mode for carrying out the present invention when the moving image photographing apparatus according to the present invention is applied to a digital camera will be described.

  FIG. 1 is a block diagram showing a schematic configuration of a digital camera according to the best embodiment.

  The digital camera includes an image processing engine 1. The image processing engine 1 has a CPU (Central Processing Unit), and in accordance with a control program stored in the non-volatile memory 2, the buffer memory 3 is used as a temporary storage work area for various circuits in the digital camera. The control process is performed.

  The subject light guided into the camera by the photographing lens 4 enters the light receiving surface of the image sensor 5. The image sensor 5 is composed of a charge coupled device (CCD), a complementary metal oxide semiconductor (CMOS), and the like, accumulates subject light incident on the light receiving surface, and captures a subject image. That is, the image pickup device 5 constitutes an image pickup means for picking up an image of a subject. When a release button, which is one of the operation units 6, is pressed halfway, the image processing engine 1 activates an autofocus function, and based on subject light detected by an AF (Auto Focus) sensor (not shown), the photographing lens 4. , And the focus of the subject image projected onto the light receiving surface of the image sensor 5 is automatically adjusted.

  The subject image formed on the light receiving surface of the image sensor 5 is converted into an analog image signal, and this image signal is input to an AFE (Analog Front End) 8 according to the timing generated by a TG (Timing Generator) 7. The AFE 8 removes noise from the analog imaging signal output from the imaging device 5 and amplifies the signal to convert it into a digital imaging signal. The digital imaging signal converted by the AFE 8 is input to the image processing engine 1 according to the timing generated by the TG 7. The image processing engine 1 performs image processing such as white balance processing and gamma correction on the input imaging signal to generate developed image data. Then, compression processing is performed to compress the developed image data at a predetermined ratio, and compressed image data such as JPEG (Joint Photographic Experts Group) or TIFF (Tagged Image File Format) is generated. If the developed image is a moving image, compression processing combining algorithms such as image compression according to JPEG, inter-frame prediction, and motion compensation is performed, and compressed image data such as MPEG (Motion Picture Experts Group) is converted. Generate.

  The compressed image data is temporarily stored in the buffer memory 3. Then, it is output to the monitor drive unit 9 and displayed on the monitor 10 made of TFT (Thin Film Transistor) liquid crystal provided on the back of the digital camera, and recorded on the memory card 12 via the recording I / F 11. . The recording I / F 11 performs write control when writing data to the memory card 12 and read control when reading data recorded on the memory card 12. The memory card 12 is a card-shaped storage medium made of a nonvolatile memory that can be attached to and detached from a card slot provided in the camera body.

  The microphone 13 constitutes a sound collecting means for collecting sound, and collects sound around the subject at the time of moving image shooting. The collected sound is output to the sound processing unit 14 as an analog sound signal, and the sound processing unit 12 converts the sound into a digital signal at a predetermined sampling rate and a predetermined number of quantization bits. This audio signal is temporarily stored as audio data in the buffer memory 3 by the image processing engine 1 and then recorded in the memory card 12 via the recording I / F 11. The audio data recorded on the memory card 12 is read out via the recording I / F 11 and output from the speaker 15 under the control of the audio processing unit 14. The memory card 12 constitutes storage means for recording a moving image picked up by the image pickup device 5 together with sound collected by the microphone 13. The data recorded on the memory card 12 is output to a personal computer or the like via an external I / F 16 such as a USB (Universal Serial Bus), and can be stored in a hard disk such as a personal computer.

  The resolution of the image stored in the memory card 12 is shown in the figure in which the user of the digital camera displays the resolution setting menu on the monitor 10 and configures the operation unit 6 from a plurality of resolutions displayed on the monitor 10. Any one can be set by operating a multi-selector that does not. In the present embodiment, any one of a high resolution of 1024 × 768 [pixel], a medium resolution of 640 × 480 [pixel], and a low resolution of 320 × 240 [pixel] can be set. The image processing engine 1 records still images and moving images on the memory card 12 at the resolution selected by the user in the resolution setting menu. The image processing engine 1 and the operation unit 6 constitute resolution setting means for setting the resolution of a moving image recorded on the memory card 12 to an arbitrary resolution from among a plurality of types.

  Further, the image processing engine 1 constitutes detection means for detecting a remaining shooting time in which a moving image picked up by the image pickup device 5 and sound collected by the microphone 13 can be recorded in the memory card 12. In the present embodiment, the image processing engine 1 detects the remaining storage capacity of the memory card 12 or the remaining battery capacity of a battery (not shown) that supplies driving power to each part of the circuit, and detects the remaining shooting time. Further, the image processing engine 1 constitutes a recording set value changing unit, and when the remaining shooting time detected by the detecting unit is equal to or less than a predetermined value, according to the type of resolution set by the resolution setting unit, The recording setting values of the sampling rate and the number of quantization bits of the sound collected by the microphone 13 and recorded on the memory card 12 are changed. The sound processing unit 14 samples and quantizes the sound collected by the microphone 13 at the changed sampling rate and the number of quantization bits of each recording setting value.

  FIG. 2 is a table showing combinations of resolutions of captured images of the digital camera and recording setting values associated with the resolution types. This combination table is stored in the nonvolatile memory 2.

  When the resolution of the captured image is 320 × 240 [pixel], the audio sampling rate is associated with 11.25 [kHz], and the audio quantization bit number is associated with 8 [bit]. In addition, when the resolution of the captured image is 640 × 480 [pixel], the audio sampling rate is 22.05 [kHz], which is twice the low resolution, and the audio quantization bit rate is 12 [bit]. It has been. When the resolution of the captured image is 1024 × 768 [pixel], the audio sampling rate is 44.1 [kHz], which is twice the medium resolution, and the audio quantization bit rate is 16 [bit]. It has been. That is, in the present embodiment, the audio sampling rate and the audio quantization bit number are set to be lower as the resolution of the set captured image is lower.

  Next, the operation of the digital camera according to the present embodiment having the above-described configuration will be described.

  First, when the photographer operates the power switch to turn on the digital camera, power is supplied to each circuit inside the digital camera, and the photographing is ready.

  Next, the photographer sets the resolution for recording the photographed image data on the memory card 12 before starting photographing. When setting the resolution of the image, the resolution selector menu screen is displayed on the monitor 10 by operating the multi selector. The resolution setting menu screen displays the above three items of resolution: high resolution of 1024 × 768 [pixel], medium resolution of 640 × 480 [pixel], and low resolution of 320 × 240 [pixel]. . The photographer designates the desired resolution item by pressing the upper side or the lower side of the multi-selector, and after completing the designation, presses the OK button to set the resolution.

  When the resolution is set, the image processing engine 1 detects the remaining storage capacity of the memory card 12 or the remaining battery capacity of the battery that supplies driving power to each part of the circuit, and detects the remaining shooting time. When detecting that the remaining shooting time is a predetermined value (for example, 30 minutes) or less, the image processing engine 1 accesses the non-volatile raw memory 2 and displays a combination of recording setting values associated with the type of resolution. With reference to FIG. 2, the audio processing unit 14 is controlled to perform audio sampling and quantization with each recording setting value associated with the set resolution.

  For example, when the photographer sets a high resolution of 1024 × 768 [pixel], each recording setting value of the audio sampling rate 44.1 [kHz] and the audio quantization bit number 16 [bit] corresponding to the high resolution is set. Is set. At high resolution, the audio data collected by the microphone 13 is sampled at the same sampling frequency as that of a music CD (Compact Disc), so the reproducibility of the audio data collected by the microphone 13 is improved. Furthermore, since the sampled data is quantized with 16 [bits], the dynamic range can be widened and the strength of the sound can be expressed. For this reason, the sound data collected by the microphone 13 is recorded with high sound quality, but the data size is not so small.

  When the photographer sets the medium resolution of 640 × 480 [pixel], the recording setting values of the audio sampling rate 22.05 [kHz] and the audio quantization bit number 12 [bit] corresponding to the medium resolution are set. Is set. At medium resolution, the audio data collected by the microphone 13 is sampled at a sampling frequency that is half that of a music CD (Compact Disc), and the sampled data is quantized at 12 [bits], so that compared to the case of high resolution The size of audio data can be reduced. However, the sampling of the audio data collected by the microphone 13 becomes coarser as the size of the audio data is reduced, and the width of the dynamic range is also reduced. For this reason, the reproducibility and strength of the sound are lowered, and the sound quality is inferior to that in the case of high resolution.

  When the photographer sets a low resolution of 320 × 240 [pixel], the recording setting values of the audio sampling rate 11.025 [kHz] and the audio quantization bit number 8 [bit] corresponding to the low resolution are set. Is set. In the low resolution, the audio data collected by the microphone 13 is sampled at a sampling frequency of 1/4 of a music CD (Compact Disc), and the sampled data is quantized at 8 [bit], so that it is compared with the case of the medium resolution. Can further reduce the size of the audio data. However, since sampling of the audio data collected by the microphone 13 becomes coarser, it becomes impossible to output high and low sounds, resulting in a muffled sound. In addition, since the width of the dynamic range becomes narrower, the intensity of the sound is lost and the sound is not sharp.

  According to such a digital camera according to the present embodiment, as described above, the remaining storage capacity of the memory card 12 or the remaining battery capacity of the battery that supplies driving power can be detected by the detection unit, and can be recorded on the memory card 12. When it is detected that the remaining recording time is less than or equal to a predetermined value, the recording setting value changing means changes the recording setting values of the sampling rate and the quantization bit number of the sound to be recorded into a resolution type, that is, a high resolution, It is changed according to medium resolution and low resolution. For this reason, when the remaining recordable recording time is short, the data size of the sound recorded on the memory card 12 can be reduced according to the recording resolution of the moving image. As a result, the remaining shooting time that can be recorded in the memory card 12 can be extended by reducing the audio data size, and shooting can be continued for a longer time.

  Further, according to the present embodiment, even in the removable memory card 12 having a limited storage capacity, the recording setting value changing unit changes the recording setting value of the sound according to the recording resolution, so that the storage capacity can be increased. You can shoot for a longer time without worrying that it will soon disappear.

  In the above embodiment, each recording set value in the combination table stored in the nonvolatile memory 2 is set in advance, but the present invention is not limited to this. For example, the digital camera user may operate the multi-selector to display the recording setting menu screen on the monitor 10 and arbitrarily set each recording setting value in the combination table. In this case, the recording setting menu screen displays the sampling rate value and the quantization bit value, and the user presses the left or right side of the multi-selector to change the digit of the sampling rate value or quantization bit value to be set. select. Subsequently, an arbitrary recording set value is set by pressing the upper or lower side of the multi selector. Here, the multi selector and the monitor 10 constitute recording setting value setting means for setting each recording setting value to an arbitrary value.

  According to this configuration, each recording set value of audio data to be recorded on the memory card 12, that is, the audio sampling rate and the number of quantization bits can be arbitrarily set. For this reason, for example, even if the recording resolution of the moving image is lowered, it is possible to record sound with high sound quality.

  In the above embodiment, the image processing engine 1 is configured to change the audio sampling rate and the number of audio quantization bits. For example, AUDIO CODEC IC which is hardware for compressing and expanding audio is used. The audio sampling rate and the audio quantization bit number may be changed.

  In the above embodiment, the case where the moving image capturing apparatus according to the present invention is applied to a digital camera has been described. However, a digital video camera that records a moving image captured by an imaging unit together with sound collected by a sound collecting unit, or a camera The present invention can be applied to various moving image photographing apparatuses such as mobile phones. Even when the present invention is applied to such a moving image photographing apparatus, the same effects as the above-described embodiment can be obtained.

1 is a block diagram showing a schematic configuration of a digital camera according to a best embodiment of the present invention. 3 is a table showing combinations of resolutions of captured images of the digital camera shown in FIG. 1 and recording setting values associated with the types of resolutions.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Image processing engine 2 ... Nonvolatile memory 5 ... Image sensor 11 ... Recording I / F
12 ... Memory card 13 ... Microphone 14 ... Audio processor

Claims (4)

Storage means for recording a moving image picked up by the image pickup means together with sound collected by the sound collecting means; and resolution setting means for setting the resolution of the moving image recorded in the storage means to an arbitrary resolution from a plurality of types. In a video shooting device equipped with
Detecting means for detecting a remaining shooting time in which the moving image and sound can be recorded in the storage means;
If the remaining shooting time detected by the detecting means is less than or equal to a predetermined value, the sound collected by the sound collecting means and recorded in the storage means according to the type of resolution set by the resolution setting means And a recording setting value changing means for changing each recording setting value of the sampling rate and the number of quantization bits. The moving image shooting apparatus according to claim 1,
The moving image photographing apparatus according to claim 1, wherein the detecting means detects a remaining storage capacity of the storage means or a remaining battery capacity of a battery that supplies driving power, and detects a remaining photographing time. In the moving image photographing device according to claim 1 or 2,
The moving image photographing apparatus, wherein the storage means is detachable from the moving image photographing apparatus. In the moving image photographing device according to any one of claims 1 to 3,
A moving image photographing apparatus comprising recording setting value setting means for setting each recording setting value to an arbitrary value.

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