JP4444748B2 - Imaging apparatus and control method thereof - Google Patents

Description

  The present invention relates to an imaging apparatus that supports a plurality of compression encoding schemes such as MPEG2 and MPEG4, and a control method therefor.

  Conventionally, video cameras are mainly used for recording and reproducing video data compression-encoded by the DV compression method using a tape as a recording medium. However, in recent years, MPEG-compatible recording media such as flash memory cards and DVDs have been used as MPEG. Products that record and play back video data that has been compression-encoded using this method have appeared. A configuration of an apparatus for recording and reproducing MPEG image data on a memory card is disclosed in, for example, Patent Document 1.

Furthermore, in a video camera using a flash memory card as a recording medium, in order to take advantage of the characteristics of the recording medium such as high compatibility with a personal computer (personal computer), a moving picture compression method based on MPEG4 suitable for a network environment is generally used. However, due to recent improvements in flash memory performance and higher read / write speeds and broadband networks, video cameras that use a higher-quality MPEG2 video compression system have also appeared.
Japanese Patent Laid-Open No. 10-210409

However, if the above-mentioned video camera can select, for example, the MPEG2 system or the MPEG4 system, the user should select which video compression system from the MPEG2 system or the MPEG4 system and under what circumstances. This is a particularly difficult task for beginners. For example, it is conceivable that an inconvenience such as unintentionally recording in a low-quality MPEG4 system a shooting scene that was planned to be copied to an MPEG2-compatible recording medium such as a DVD later.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide an imaging apparatus and a control method therefor that can easily select an appropriate image compression method for the environment even for beginners.

In order to solve the above-described problem, an imaging apparatus according to the present invention includes a plurality of codes capable of compressing the information amount of the image signal in the imaging device that compresses the information amount of the image signal generated by imaging and records the information on a recording medium. Image encoding means corresponding to the encoding method, recording means for recording the image signal encoded by the image encoding means on the recording medium, and reproducing means for reproducing the image signal recorded on the recording medium, An image output means for outputting the image signal reproduced by the reproduction means to the outside, and a type of connection cable connected to the image output means when the reproduction means is in a mode capable of reproducing the recorded image signal. storage means for storing information for selecting an encoding scheme in said image encoding means is determined according to the class, in accordance with information stored in said storage means, put on the image encoding means Characterized in that a coding method selection means for selecting one of the coding schemes from a plurality of coding schemes.

According to another aspect of the present invention, there is provided a control method for an imaging apparatus, wherein the information amount of an image signal generated by imaging is compressed and recorded on a recording medium. An image encoding step corresponding to the encoding method, a recording step for recording the image signal encoded in the image encoding step on the recording medium, and a reproduction step for reproducing the image signal recorded on the recording medium, An image output step for outputting the image signal reproduced in the reproduction step to the outside from an output terminal, and a connection cable connected to the output terminal when the imaging apparatus is in a mode capable of reproducing the recorded image signal a storage step of storing information for selecting a coding scheme in the image encoding step is determined according to the kind, stored in the storing step According information, and having a coding scheme selection step of selecting one coding scheme from said plurality of coding schemes in the image encoding step.

According to the present invention, by storing information for selecting a coding scheme is determined depending on the type of the connected connection cable, for example, the encoding method corresponding to the information stored at the next startup It becomes possible to select automatically, and an image compression method suitable for the user's usage environment can be easily selected.

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

<First Embodiment>
A first embodiment in which the present invention is implemented with a digital video camera will be described with reference to the drawings.

  FIG. 1 is a block diagram of this embodiment. In the figure, 101 is a photographic lens that captures a subject, 102 is an aperture that controls the amount of light to an image sensor described later, 103 is an image sensor that converts the captured subject into an image signal, and 104 samples and holds the image signal. The CDS / AGC 105 for setting an appropriate signal level is a digital signal processing circuit that performs A / D conversion on the image signal from the CDS / AGC and performs digital signal processing, and 106 is raw data from the digital signal processing circuit. A frame memory 107 for storing the image data one frame at a time is a pixel number adjustment circuit for adjusting an appropriate number of pixels so that the pixels of the frame memory can be recorded in the later-described MPEG2 or MPEG4 system. Each unit described above operates in the shooting / recording mode.

  108 is an image / audio data bus for moving image data and audio data described later between blocks, 109 is a microphone for collecting audio recorded together with the image data, and 110 is an audio signal from the microphone. An amplifier 111 for amplifying the sound signal to an appropriate level is an A / D converter for A / D converting the amplified audio signal.

  Reference numeral 112 denotes a liquid crystal display for displaying reproduced image data from an MPEG2 codec 114 or an MPEG4 codec 115 described later in the reproduction mode, and a liquid crystal display for displaying the video imaged by the image sensor 103 in the photographing mode. 113 drives the liquid crystal display 112. It is a liquid crystal driver.

  Reference numeral 114 denotes a digital image signal from the image / audio data bus 108 as a moving image in the shooting mode, and the amount of information is compressed by the MPEG2 method. In the reproduction mode, the image / audio data bus 108 is reproduced in a flash memory described later. The MPEG2 codec 115 for decompressing the MPEG2 compressed data from the digital video signal 115 in the shooting mode uses the digital image signal from the image / audio data bus 108 as a moving image, compresses the amount of information by the MPEG4 system, and in the playback mode, a flash memory described later. The MPEG4 codec 116 that decompresses the MPEG4 compressed data from the image / audio data bus 108 reproduced in the above is a switching switch for switching the codec used to selectively use the MPEG2 codec 114 and the MPEG4 codec 115. It is a switch.

  A plurality of cables 117 can be connected. Depending on the type of cable to be connected, an analog video signal from an NTSC encoder described later or digital video data from a USB interface described later is output and the connected cable A multi-connector 118 that detects the type of the image is converted into an analog image that is the same as that displayed on the liquid crystal display 112, and is output to the multi-connector 117. An NTSC encoder 119 is an MPEG2 recorded on a memory card, which will be described later, or This is a USB interface that outputs MPEG4 image data as it is to the outside.

  120 is a card driver for reading and writing data to a memory card, which will be described later, 121 is a memory card for recording MPEG2 image data or MPEG4 image data from the image / audio data bus 108, and 122 is a user's main body An operation key 123 for performing an operation on the main microcomputer 123 controls the mode of the entire apparatus, or a main microcomputer for controlling the execution of various functions by reading commands to the operation key 122. The EEPROM 125, which is a non-volatile memory that stores the above state even when the power is turned off, is a control bus through which control signals from the main microcomputer 123 and control signals from the operation keys 122 come and go.

  FIG. 2 is a diagram showing details of the multi-connector 117. In the figure, 201 is a connector installed on the main body side of the digital video camera of this embodiment, 202 is a plug of an analog AV cable, 203 is a plug of a USB cable, and the opposite side of each cable is a general-purpose pin plug and It has the shape of a USB-B plug. The multi-connector 117 is composed of nine pins, 204 is an analog ground, 205 is an analog left channel audio, 206 is an analog right channel audio, and 207 is for detecting an analog cable in S302b described later. The detection terminal 208 is a digital (USB) ground, 209 and 210 are digital serial data signal terminals, 211 is a power supply terminal capable of supplying power as USB bus power (not used in this embodiment), and 212 is This is a detection terminal for detecting the USB cable in S302b described later. The MPEG2 codec 114 in the present embodiment encodes an interlaced scanned image of NTSC-compliant horizontal 720 × vertical 480 pixels / 29.97 frames per second as it is and records at a high rate of 3 to 6 Mbps on average. An optimum moving image can be recorded on a general television monitor. Furthermore, DVD is also highly compatible. The MPEG4 codec 115 converts the NTSC-compliant image into a sequentially scanned image of 320 vertical x 240 horizontal pixels / 15 frames per second by the pixel number adjusting circuit 107 and encodes it, and the average is low at 0.5 to 1 Mbps. Since recording is performed at a rate, a moving image with a light and smooth movement can be obtained even when the distribution is performed through the Internet or the like by a personal computer. It is also characterized by high compatibility with playback software such as a media player on a personal computer.

  With the above configuration, the operation of the digital video camera of the present embodiment will be described with reference to the flowchart of FIG. FIG. 3A is a flowchart showing an operation when the power is turned on in the shooting mode of the digital video camera of the present embodiment. In the figure, after the power is turned on in S301a, it is detected in S302a whether setting information for recording with the MPEG2 or MPEG4 codec is stored in the EEPROM 124. Then, the setting information is read in S303a, identified in S304a, and if it is MPEG4 setting information, the recording mode is set in MPEG4 in S305a, and MPEG4 is set as setting information for the next activation in S306a. The data is recorded in the EEPROM 124, and the photographing standby state is entered in S307a. If it is determined that the setting information is MPEG2 in S304a, the recording mode is set in MPEG2 in S308a, MPEG2 is recorded in the EEPROM 124 as setting information for the next start-up in S309a, and in S307a. To enter shooting standby mode.

  FIG. 3B is a flowchart showing an operation at the time of reproduction of the digital video camera of the present embodiment. When the playback mode is started by the user's operation in S301b, the connection cable is detected in S302b. When the USB cable is detected, it is determined that the connection partner is a personal computer, and the USB interface 119 transfers the memory card 121 to the memory card 121. In the file transfer mode in which the recorded compressed image data can be read out, MPEG4 is recorded in the EEPROM 124 as setting information for the next start-up in S303b, and in S304b, the personal computer waits for reading of the predetermined compressed image data. It becomes a state. When an analog AV cable is detected in S302b, an analog AV signal is output from the NTSC encoder 118. In S305b, MPEG2 is recorded in the EEPROM 124 as setting information for the next activation, and S306b. Then, a standby state for a reproduction operation by the user is entered.

Above, that represents the configuration described in the illustration is FIG.

  In this embodiment, the MPEG2 codec or the MPEG4 codec is selected when the power is turned on. However, it is of course possible to adopt a configuration in which the user can reselect as necessary after the selection. In this embodiment, MPEG2 or MPEG4 is selected depending on the type of cable to be connected. However, information on the connected external device is detected, and MPEG2 or MPEG4 is selected according to the type of external device. In addition, when the transfer mode of the digital cable is a stream transfer having a transfer speed according to the playback speed of 1 × speed, the memory card is used regardless of the playback time. In a file transfer mode in which the data recorded in 121 is read at the highest speed, MPEG4 may be selected. Furthermore, it is good also as a structure which can prohibit use of either compression encoding system by a user's setting.

<Second Embodiment>
Next, a second embodiment in which the present invention is applied to a digital video camera will be described with reference to the drawings.

  FIG. 5 is a block diagram of this embodiment. In the figure, reference numeral 500a denotes a digital video camera body, and 500b denotes a docking station that can input and output signals and charge a rechargeable battery described later, and is detachable from the digital video camera. Reference numeral 501 denotes a photographing lens that captures an object, 502 an aperture that controls the amount of light to an image sensor, which will be described later, 503 an image sensor that converts the captured object into an image signal, and 504 that samples and holds the image signal to obtain an appropriate signal. CDS / AGC and 505 for converting the level into a digital signal processing circuit for A / D converting the image signal from the CDS / AGC and performing digital signal processing, and 506 for raw data from the digital signal processing circuit for one frame. A frame memory 507 for accumulating each pixel is a pixel number adjusting circuit that adjusts an appropriate number of pixels so that the pixels of the frame memory can be recorded in the MPEG2 or MPEG4 system described later.

  Reference numeral 508 denotes an image / audio data bus through which image data between blocks and audio data described later come and go; 509, a microphone that collects audio recorded together with the image data; and 510, an audio signal from the microphone as appropriate. An amplifier 511 for amplifying to a certain level, an A / D converter for A / D converting the amplified audio signal, and 512 for reproduction image data from an MPEG2 codec 514 (to be described later) or an MPEG4 codec 515 (to be described later) in the reproduction mode, A liquid crystal display 513 that displays an image captured by the image sensor 503 at the time of shooting is a liquid crystal driver that drives the liquid crystal display 512.

514, while compressing Ri by the digital image signal to the MPEG2 method as videos from the image / audio data bus 508, MPEG2 CODEC for decompressing MPEG2 compressed data recorded in the flash memory will be described later, 515, the image / the digital image signal with compressing Ri by the MPEG4 system as video from the audio data bus 508, MPEG4 codec for decompressing MPEG4 compressed data recorded in the flash memory will be described later, 516, the said MPEG2 cODEC 514 MPEG4 codec 515 It is a changeover switch for switching between.

  Reference numeral 517 denotes a station connector for connecting the digital video camera main body 500a and the docking station 500b. Reference numeral 518 denotes an NTSC encoder for converting the same image as that displayed on the liquid crystal display 512 and outputting it to the multi-connector 529. The USB interface outputs MPEG2 or MPEG4 format image data recorded on a memory card, which will be described later, to the outside as it is.

  520 is a card driver for reading and writing data to a memory card, which will be described later. 521 is a memory card for recording MPEG2 image data or MPEG4 image data from the image / audio data bus 508. An operation key 523 for performing an operation on the main microcomputer controls the mode of the entire device, or controls the execution of various functions by reading the state of the operation key 522, and 524 indicates a predetermined state of the main microcomputer. EEPROM 525 which is a non-volatile memory that stores the memory even when the power is turned off is a control bus through which a control signal from the main microcomputer 523 and a signal from the operation key 522 come and go.

  A rechargeable battery 526 is a power source of the digital video camera 500a, a charge control unit 527 that charges the rechargeable battery, detects full charge, and stops charging, 528 includes the digital video camera body 500a. The station connector 529 for connecting the docking station 500b outputs an analog video signal from the NTSC encoder 518 or digital video data from the USB interface 519 and is connected depending on the type of cable to be connected. A multi-connector that detects the type of cable.

  The details of the multi-connector 529 of the present embodiment are the same as those of FIG. 3 showing the details of the multi-connector 117 of the first embodiment, but are installed in the docking station 500b instead of the digital video camera 500a main body. This is different from the first embodiment. In addition, the MPEG2 codec in the present embodiment encodes an interlaced scan image of NTSC-compliant horizontal 720 × vertical 480 pixels / 29.97 frames per second as it is, and records it at a high rate of 3 to 6 Mbps on average. It is possible to record an optimal moving image on a TV monitor. Furthermore, DVD is also highly compatible. The MPEG4 codec converts the NTSC-compliant image into a sequentially scanned image of 320 × vertical 240 pixels / 15 frames per second by the pixel number adjustment circuit 107 and encodes it to a low rate of 0.5 to 1 Mbps on average. Therefore, even when distributing via the Internet or the like by a personal computer, it is possible to obtain a moving image with a light load and smooth movement. It is also characterized by high compatibility with playback software such as a media player on a personal computer.

  With the above configuration, the operation of the digital video camera of the present embodiment will be described using a flowchart. The operation when the power is turned on in the shooting mode of the digital video camera according to the present embodiment is the flowchart shown in FIG. FIG. 6 is a flowchart showing the operation when the digital video camera of this embodiment is connected to the docking station. Note that the power source of the digital video camera is off. When the user connects to the docking station in S601, the connection detection program in the main microcomputer 523 is activated in S602, the connection cable is detected in S603, and the USB cable is detected. In step S604, MPEG4 is recorded in the EEPROM 524 as setting information for the next start-up, and in step S605, the connection detection program ends. If an analog AV cable is detected in S603, MPEG2 is recorded in the EEPROM 124 as setting information for the next activation in S606, and the connection detection program is terminated in S605.

FIG. 7 shows the configuration described above in an illustration.

  In this embodiment, MPEG2 or MPEG4 is selected when the power is turned on, but it is of course possible to adopt a configuration in which the user can reselect as necessary after the selection. Moreover, it is good also as a structure which can prohibit use of either compression encoding system by a user's setting. Further, when the charge amount of the rechargeable battery 526 is reduced when the digital video camcorder main body and the docking station are connected, the charging control unit 527 may perform charging.

<Other embodiments>
Also, an object of the present invention is to supply a storage medium (or recording medium) that records a program code of software that realizes the functions of the above-described embodiments to a system or apparatus, and to perform computer (or CPU or CPU) of the system or apparatus. Needless to say, this can also be achieved when the MPU) reads and executes the program code stored in the storage medium. In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention. Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an operating system (OS) running on the computer based on the instruction of the program code. It goes without saying that a case where the function of the above-described embodiment is realized by performing part or all of the actual processing and the processing is included. Examples of the storage medium for storing the program code include a flexible disk, hard disk, ROM, RAM, magnetic tape, nonvolatile memory card, CD-ROM, CD-R, DVD, Blu-ray disk, optical disk, and magneto-optical disk. , MO, etc. are conceivable.

  Furthermore, after the program code read from the storage medium is written into a memory provided in a function expansion card inserted into the computer or a function expansion unit connected to the computer, the function is determined based on the instruction of the program code. It goes without saying that the CPU or the like provided in the expansion card or the function expansion unit performs part or all of the actual processing and the functions of the above-described embodiments are realized by the processing.

  When the present invention is applied to the storage medium, the storage medium stores program codes corresponding to the flowcharts described above.

1 is a block diagram of a digital video camera according to a first embodiment of the present invention. It is a figure which shows the detail of the multi connector in the 1st Embodiment and 2nd Embodiment of this invention. (A), (b) is a flowchart which shows operation | movement of the digital video camera in the 1st Embodiment of this invention. It is a figure which shows the system outline | summary in the 1st Embodiment of this invention. It is a block diagram of the digital video camera and docking station in the 2nd Embodiment of this invention. It is a flowchart which shows operation | movement of the digital video camera in the 2nd Embodiment of this invention. It is a figure which shows the system outline | summary in the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Shooting lens 102 Aperture 103 Image sensor 104 CDS / AGC
105 Digital Signal Processing Circuit 106 Frame Memory 107 Pixel Number Adjustment Circuit 108 Image / Audio Data Bus 109 Microphone 110 Amplifier 111 A / D Converter 112 Liquid Crystal Display 113 Liquid Crystal Driver 114 MPEG2 Codec 115 MPEG4 Codec 116 Changeover Switch 117 Multi Connector 118 NTSC Encoder 119 USB interface 120 Card driver 121 Memory card 122 Operation keys 123 Main microcomputer 124 EEPROM
125 Control bus 201 Main body side connector 202 Analog AV cable plug 203 USB cable plug 204 Analog ground 205 Analog left channel audio 206 Analog right channel audio 207 Detection terminal 208 Digital ground 209 Digital serial data signal terminal 210 Digital Serial data signal terminal 211 Power supply terminal 212 Detection terminal 500a Digital video camera 500b Docking station 501 Shooting lens 502 Aperture 503 Image sensor 504 CDS / AGC
505 Digital signal processing circuit 506 Frame memory 507 Pixel number adjustment circuit 508 Image / audio data bus 509 Microphone 510 Amplifier 511 A / D converter 512 Liquid crystal display 513 Liquid crystal driver 514 MPEG2 codec 515 MPEG4 codec 516 Changeover switch 517 Station connector 518 NTSC encoder 519 USB interface 520 card driver 521 memory card 522 operation key 523 main microcomputer 524 EEPROM
525 Control bus 526 Rechargeable battery 527 Charge controller 528 Station connector 529 Multi-connector

Claims (5)

In an imaging device that compresses an information amount of an image signal generated by imaging and records it on a recording medium,
Image encoding means corresponding to a plurality of encoding methods capable of compressing the information amount of the image signal;
Recording means for recording the image signal encoded by the image encoding means on the recording medium;
Reproducing means for reproducing the image signal recorded on the recording medium;
Image output means for outputting the image signal reproduced by the reproduction means to the outside;
Wherein when reproducing means of the recorded playable mode image signal, for selecting an encoding scheme in said image encoding means is determined according to the kind of the connected connection cable to the image output unit Storage means for storing information for,
An imaging apparatus comprising: an encoding method selection unit that selects one encoding method from the plurality of encoding methods in the image encoding unit in accordance with information stored in the storage unit. The coding method selection means according to the information stored in the storage means, when the imaging device is turned to the power-on state, the one coding scheme from said plurality of encodings in said image encoding means The imaging apparatus according to claim 1, wherein the imaging apparatus is selected. Further comprising detection means for detecting the type of connection cable connected to the image output means,
The storage means stores information for selecting a different encoding method when an interface cable for digital output is detected by the detection means and when an AV cable such as an analog output is detected. The imaging apparatus according to claim 1 or 2. Wherein the image output means, the imaging apparatus according to any one of claims 1 to 3, characterized in that it comprises a docking station portion detachable from the imaging device. In a control method of an image pickup apparatus that compresses an information amount of an image signal generated by image pickup and records it on a recording medium
An image encoding step corresponding to a plurality of encoding methods capable of compressing the information amount of the image signal;
A recording step of recording the image signal encoded in the image encoding step on the recording medium;
A reproduction step of reproducing the image signal recorded on the recording medium;
An image output step of outputting the image signal reproduced in the reproduction step to the outside from an output terminal;
When the imaging apparatus of the recorded playable mode image signal, for selecting a coding scheme in the image encoding step is determined according to the kind of the connected connection cable to the output terminal A storage step for storing the information of
An imaging apparatus control method comprising: an encoding method selection step of selecting one encoding method from the plurality of encoding methods in the image encoding step according to the information stored in the storage step.

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