JP5063382B2 - Recording / reproducing apparatus, recording apparatus and reproducing apparatus - Google Patents

Description

The present invention relates to a recording / reproducing apparatus , a recording apparatus, and a reproducing apparatus , and more specifically, a recording / reproducing apparatus having a function of recording image information on a recording medium and a function of outputting recorded image information to the outside , The present invention relates to a recording apparatus and a reproducing apparatus .

  In recent years, recording / reproducing apparatuses such as video cameras for recording / reproducing images using an information recording medium such as an optical disk have appeared. Many of these recording / reproducing apparatuses include an external device connecting unit including a digital interface such as USB or IEEE1394. For example, it is possible to connect a video camera to an external device such as a personal computer and transfer data recorded on the information recording medium to the external device.

  When data is read from or written to a disk-shaped recording medium such as an optical disk or a hard disk device, an operation for positioning a pickup such as an optical pickup or a magnetic head on a desired track, a so-called seek operation is required. Such mechanical control of the movable part is an obstacle that slows down the access speed. For example, a seek operation for searching for a target track on an optical disc takes about several tens of milliseconds.

  Normally, when a computer is connected to a recording / reproducing apparatus that is a disk-shaped recording medium, data is read from the disk-shaped recording medium in comparison with the time required to transfer commands and data between the computer and the recording / reproducing apparatus. It takes a long time. Therefore, the computer is kept waiting during data reading.

Patent Document 1 describes that in an information reproducing apparatus, data read processing time from a disk-shaped recording medium is substantially shortened by using a prefetch buffer. When the data requested to be read from the external device exists in the prefetch buffer, that is, when a hit occurs, the desired data may be immediately read from the prefetch buffer and transferred to the external device. The time from when the external device issues a data read command until the desired data is acquired is shortened, and apparently the response speed of the recording / reproducing apparatus is increased.
JP 2001-176247 A

  In the technique described in Patent Document 1, data at a sector address following a sector address is received in a prefetch buffer unconditionally in response to a read request. Therefore, it is effective when related data are continuously arranged in the order of sector numbers. However, when data is distributed and recorded in a plurality of discontinuous sectors, particularly a plurality of sectors having different radial positions, the hit rate is remarkably lowered, and the prefetching function cannot be utilized. This means that it takes a long time to read data when viewed from an external device.

  For example, a file system UDF (Universal Disc Format) employed for a rewritable optical disc employs a virtual allocation table (VAT). In this file system, in order to read file management information, it is necessary to read VAT from the optical disk first, and many seek operations occur. Inevitably, the prefetch buffer hit rate is significantly reduced.

In view of such problems, an object of the present invention is to provide a recording / reproducing apparatus , a recording apparatus, and a reproducing apparatus that increase the response speed to an external device.

Code recording and reproducing apparatus according to the present invention includes an input means for inputting an image signal, in which the memory, the image signal input by pre Symbol input means encodes, and stores the image signal encoded in the memory Reading the encoded image signal from the memory , recording the read image signal on a recording medium in accordance with a file system , reproducing the encoded image signal from the recording medium, and reproducing the reproduction and access means for storing the image signals in the memory, reading out the image signal the coded from the memory, a decoding hand stage you decode the image signal read out, a connecting means for connecting the external device, A recording mode in which the access means records an image signal, a playback mode in which the access means reproduces an image signal, and the external device via the connection means Instructing means for instructing one of a plurality of modes including an external connection mode for accessing the recording medium, and means for changing the setting of the memory according to the mode instructed by the instructing means, the recording mode And in the reproduction mode, a predetermined storage area in the memory is set as a storage area for the encoded image signal, and in the external connection mode, the predetermined area in the memory is set as the file system. Control means for setting as a storage area for the management information, and the control means so that the encoding means stores the encoded image signal in the predetermined storage area in the recording mode. Controlling and in the reproduction mode, the access means reproduces the image signal reproduced from the recording medium in the predetermined storage area. In the external connection mode, the access means controls to store the management information reproduced from the recording medium in the predetermined storage area in the memory, and the management is performed from the external device. When there is a request for information, the management information is read from the predetermined storage area in the memory and transmitted to the external device by the connection means .
The recording apparatus according to the present invention includes an input unit that inputs an image signal, a memory, an encoding unit that encodes the image signal input by the input unit, and stores the encoded image signal in the memory. , Reading the encoded image signal from the memory, recording the read image signal on a recording medium according to a file system, connection means connecting to an external device, and the access means recording the image signal Instruction means for instructing one of a plurality of modes including a recording mode and an external connection mode in which the external device accesses the recording medium via the connection means; and the memory according to the mode instructed by the instruction means In the recording mode, a predetermined storage area in the memory is stored in the encoded image. Control means for setting the predetermined area in the memory as a storage area for management information of the file system in the external connection mode, and the control means, In the recording mode, the encoding means is controlled to store the encoded image signal in the predetermined storage area in the memory, and in the external connection mode, the access means reproduces from the recording medium. Control the storage of the management information in the predetermined storage area, and when there is a request for the management information from the external device, the management information is read from the predetermined storage area of the memory Is transmitted to the external device.
The reproduction apparatus according to the present invention includes a memory, an access unit that reproduces an encoded image signal from a recording medium according to a file system, and stores the reproduced image signal in the memory, and the encoded image signal from the memory. Decoding means for reading an image signal, decoding the read image signal, connection means for connecting to an external device, a playback mode for reproducing the image signal by the access means, and the recording by the external device via the connection means Instructing means for instructing one of a plurality of modes including an external connection mode for accessing a medium, and means for changing the setting of the memory in accordance with the mode instructed by the instructing means, wherein in the playback mode A predetermined storage area in the memory is set as a storage area for the encoded image signal, and the external connection mode Control means for setting the predetermined area in the memory as a storage area for management information of the file system, the control means in the playback mode, the access means from the recording medium The reproduced image signal is controlled to be stored in the predetermined storage area in the memory, and the management information reproduced from the recording medium by the access means in the external connection mode is stored in the predetermined storage area in the memory. And when the management information is requested from the external device, the management information is read from the predetermined storage area in the memory and transmitted to the external device by the connecting means. Features.

  According to the present invention, it is possible to speed up the response to an external device by pre-reading the file system management information of the recording medium in the memory. As a memory for this purpose, a memory used for image encoding and decoding is diverted, so that it can be realized at low cost without additional hardware.

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

  FIG. 1 shows a schematic block diagram of a video camera which is a first embodiment of a recording / reproducing apparatus according to the present invention.

  The video camera 10 includes an imaging unit 12 that converts an optical image of a subject into an image signal as image input means. The camera signal processing device 14 converts the image signal from the imaging unit 12 into video data of a predetermined format. The encoding processing device 16 compresses and encodes the video data from the camera signal processing device 14 using the MPEG2 method or the like, and generates stream data in a fixed format including encoded image information. The disk access device 18 serving as a recording medium access means performs data writing to and reading from the recording medium 20 in accordance with commands according to ATAPI. The LCD control device 22 drives a liquid crystal display device (LCD) 24 to display an image. The decoding processing device 26 decodes the compressed video data recorded on the recording medium 20. The video output terminal 28 can output the video signal being recorded and the video data being played back to the outside.

  The CPU 30 controls the whole using the RAM 34 as a main memory according to a program stored in the ROM 32. The RAM 34 is also used as a storage area for storing temporary data. The memory 36 is used as a frame memory or a work memory for the encoding processing of the encoding processing device 16 and the decoding processing by the decoding processing device 26. The memory 36 can also be used as a buffer for temporarily storing data to be recorded on the recording medium 20 and as a buffer for temporarily storing data read from the recording medium 20. The memory control device 38 controls access to the memory 36.

  The external connection interface (IF) 40 includes, for example, a digital interface such as a USB, and can transmit / receive digital data, control commands, and the like to / from an external device such as the computer 50. Although details will be described later, in the present embodiment, the memory 36 is also used when image information is transferred to the computer 50 via the external connection IF 40.

  The operation unit 42 includes various operation keys, operation switches, operation dials, and the like, and is used by the user to input various instructions and settings to the CPU 30. The above-described functional elements including the CPU 30 are connected to the bus 44, and the CPU 30 controls the above-described functional elements via the bus 44. The bus 44 is used to transfer control commands and their responses, and various data. For example, the CPU 30 controls the disk access device 18 by a command according to ATAPI (AT Attachment Packet Interface). The computer 50 connected to the external connection IF 40 can also read / write data from / to the recording medium 20 via the disk access device 18 using the ATAPI command.

  For example, when the external connection IF is USB, the computer 50 recognizes the video camera 10 connected according to the USB standard as mass storage. A subclass of the mass storage class of the USB protocol includes an ATAPI command, and the computer 50 can access the recording medium 20 of the video camera 10 using the ATAPI command. When the video camera 10 is connected to the computer 50, the computer 50 first tries to read the UDF management area of the recording medium 20. In this embodiment, with respect to reading of the UDF management area, the following configuration is adopted to achieve high speed. Of course, this contributes to speeding up the reading of data in the data area.

  The basic operation of this embodiment will be described. The video camera 10 has an operation mode of a recording mode, a reproduction mode, and an external connection mode, and uses the memory 36 in any operation mode. The operation unit 42 can be switched to a desired operation mode.

  The basic operation of the recording mode will be described with reference to FIG. FIG. 2 shows a memory map of the memory 36 and a data flow in the recording mode. The memory control device 38 divides the storage area of the memory 36 into a video frame area (VFR area) 60, a stream area 62, and an ECC area 64. In the VFR area 60, video data can be stored in one or more frames in units of frames.

  The imaging unit 12 converts the optical image of the subject into an image signal and outputs it to the camera signal processing device 14. The camera signal processing device 14 converts the image signal from the imaging unit 12 into video data of a predetermined format. The video data generated by the camera signal processing device 14 is written into the VFR area 60 of the memory 36 via the memory control device 38 (S1).

  The LCD control device 22 reads the frame video data in the VFR area 60 of the memory 36 and drives the LCD 24 according to the frame video data. Thereby, the image of the subject is displayed on the screen of the LCD 24. When displaying the video being recorded, during the following recording operation, the LCD control device 22 reads the frame video data in the VFR area 60 of the memory 36 and drives the LCD 24 according to the frame video data.

  When the user instructs the start of recording through the operation unit 42, the CPU 30 instructs the encoding processing device 16 and the disk access device 18 to start the recording operation. In response to this instruction, the encoding processing device 16 reads out the video data in the VFR area 60 via the memory control device 38 (S2), and compresses and encodes it according to the MPEG2 method to generate stream data. The generated stream data is written into the stream area 62 of the memory 36 via the memory control device 38 (S3).

  The disk access device 18 reads the stream data in the stream area 62 via the memory control device 38 (S4), performs error correction coding, and generates stream data with an ECC code (error correction parity). The generated stream data with ECC code is written into the ECC area 64 of the memory 36 via the memory control device 38 (S5). Thereafter, the disk access device 18 reads the ECC-coded stream data in the ECC area 64 (S6) and records it on the recording medium 20 (S7).

  The basic operation of the playback mode will be described with reference to FIG. FIG. 3 shows a memory map of the memory 36 and a data flow in the reproduction mode. The memory map of the memory 36 may be the same as in the recording mode.

  When the user instructs the start of playback through the operation unit 42, the CPU 30 instructs the decryption processing device 26 and the disk access device 18 to start the playback operation. In accordance with this instruction, the disk access device 18 reads the stream data with ECC code of the specified video information from the recording medium 20 (S11). Data read from the recording medium 20 is written into the ECC area 64 via the memory control device 38 (S12). Next, the disk access device 18 reads the stream data with ECC code from the ECC area 64 (S13), and corrects the error of the stream data using the ECC code. The stream data whose error has been corrected is written into the stream area 62 of the memory 36 via the memory control device 38 (S14).

  The decoding processing device 26 reads the stream data in the stream area 62 (S15) and decodes it. Thereby, the video data is reproduced. The reproduced video data is written into the VFR area 60 of the memory 36 via the memory control device 38 (S16).

  The video data in the VFR area 60 is read to the LCD control device and / or the video output terminal 28 in raster order (S17). The LCD control device 22 drives the LCD 24 according to the frame video data from the VFR area 60. As a result, the video of the subject is displayed on the screen of the LCD 24, and video data is output from the video output terminal 28 to the outside.

  The operation in the external connection mode will be described with reference to FIG. FIG. 4 shows a memory map of the memory 36 and a data flow in the external connection mode. The memory control device 38 sets the area defined as the stream area 62 in the recording mode and the reproduction mode as a transfer data area 66 for temporarily storing data exchanged with an external device. Of course, the transfer data area 66 may be narrower or wider than the stream area 62. The VFR area 60 may be included in the transfer data area 66.

  When the user instructs the start of data output to an external device (computer 50 in the illustrated example) by the operation unit 42, the CPU 30 instructs the disk access device 18 to read the designated moving image. In accordance with this instruction, the disk access device 18 reads the stream data with ECC code of the specified video information from the recording medium 20 (S21). Data read from the recording medium 20 is written into the ECC area 64 via the memory control device 38 (S22). Next, the disk access device 18 reads the stream data with the ECC code from the ECC area 64 (S23), and corrects the error of the stream data using the ECC code. The stream data whose error has been corrected is written into the transfer data area 66 of the memory 36 via the memory control device 38 (S24).

  The stream data in the transfer data area 66 is sequentially read to the external connection IF 40 (S25) and transferred from the external connection IF 40 to the computer 50.

  The recording medium 20 is, for example, an optical disk that employs a UDF file system, and here, it is assumed that the recording medium 20 is a rewritable optical disk such as a DVD-RW. FIG. 5 is a schematic configuration diagram of the file system UDF of the recording medium 20. UDF is adopted in many disk media such as DVD video, DVD-R, and DVD-RW.

  In the innermost circumference, recording management data (RMD) 70 is arranged. The RMD 70 indicates how much of the recording medium 20 has been recorded, that is, the next writing start position. A UDF area 72 is arranged following the RMD 70. The UDF area 72 stores file management information, that is, information indicating the attributes (file name, date, size, etc.) of each file recorded on the recording medium 20 and the recording position on the recording medium 20. In the present embodiment, it is assumed that the size of the UDF area 72 is composed of 0x2FF0 sectors (one sector is 2 KB). The moving image data 74 is arranged outside the UDF area 72. The moving image data 74 includes stream data with ECC code and its additional data.

  The computer 50 as an external device can access the recording medium 20 in accordance with the USB mass storage ATAPI protocol. FIG. 6 shows a procedure for reading the moving image data 74. FIG. 7 shows a procedure for accessing the UDF area 72.

  The computer 50 transmits a read request command to the video camera 10 according to the ATAPI protocol. The read command includes information on the address where the data is stored and the size of the data. The video camera 10 that has received the command reads data of the requested size from the requested address from the recording medium 20 and transmits it to the computer 50. The computer 50 transmits an ACK command indicating completion of reception to the video camera 10. These request command, data transfer and ACK command are one set.

  In the USB mass storage ATAPI, the read unit is 64 kbytes for the moving image data 74, but 2 kbytes for the UDF area 72 is different.

  An operation of the video camera 10 in the external connection mode will be described. FIG. 8 shows an operation flowchart of the video camera 10 when the mode is switched to the external connection mode. When the mode is switched to the external connection mode, first, it is checked whether or not the recording medium 20 is loaded (S41). If the recording medium 20 is not inserted (S41), the recording medium 20 is waited for insertion.

  When the recording medium 20 is inserted (S41), the CPU 30 mounts the recording medium 20 so that the recording medium 20 can be accessed (S42). Next, the CPU 30 controls the memory control device 38 to read all the UDF area 72 of the recording medium 20 and store it in the transfer data area 66 of the memory 36. In the present embodiment, the UDF area 72 exists at 0 to 0x2FF0 of a logical address (LBA: Logical Block Address). All data of the logical addresses 0 to 0x2FF0 are stored in the transfer data area 66 of the memory 36 in advance.

  FIG. 9 shows an operation flowchart of the video camera 10 when a read request command for the recording medium 20 is input from the computer 50.

  In response to the read request command from the computer 50, it is determined whether or not the requested address is in the range of logical addresses 0 to 0x2FF0 which is a UDF area (S51). When the UDF area is targeted (S51), since it has been prefetched to the memory 36, the CPU 30 reads the corresponding data from the memory 36 and transmits it to the computer 50 via the external connection IF 40 (S52). When the target is outside the UDF area (S51), the CPU 30 transfers this command to the disk access device 18 to read data from the corresponding address of the recording medium 20 (S53). The data read from the recording medium 20 is transferred to the computer 50 via the transfer data area 66 of the memory 36 and the external connection IF 40 as described with reference to FIG.

  Since the data in the UDF area 72 is pre-read in the memory 36 at the time of mounting, the requested data can be transmitted to the computer 50 without accessing the recording medium 20 in response to a data request in the UDF area. That is, it is possible to save the time required from reading request of the recording medium 20 to data acquisition. As the amount of data increases, this difference increases and apparently the response speed to the computer 50 can be increased.

  As described above, in this embodiment, the memory area used for compression encoding / decoding of an image in the recording mode and the reproduction mode is used as a temporary storage buffer for transfer data in the external connection mode. The data capacity of a memory area used for compression encoding / decoding of moving images is very large as a data transfer buffer. Accordingly, a large amount of recording data from the recording medium 20 can be prefetched into the transfer data area 66.

  The data in the UDF area 72 is prefetched into the memory 36 at the time of mounting. However, if the transfer data area 66 is empty, a part of the moving image data 74 may be prefetched. For example, the moving image recorded immediately before or the first recorded moving image is often reproduced and displayed first for the purpose of overviewing or listing the recorded contents of the recording medium 20. The data to be displayed first after connecting in this manner is prefetched in the memory 36, so that the response speed becomes faster and a comfortable operation feeling can be obtained.

  A second embodiment of the present invention will be described. In the first embodiment, the data in the UDF area of the recording medium 20 is prefetched into the transfer data area 66 of the memory 36 in response to the user switching to the external connection mode or the subsequent mounting of the recording medium 20. On the other hand, in the present embodiment, the connection of the computer 50 to the external connection IF 40 is detected, and the data in the UDF area of the recording medium 20 is prefetched into the transfer data area 66 of the memory 36. FIG. 11 shows a flowchart of the operation.

  FIG. 10 shows a configuration in which the computer 50 is connected with a USB cable when the external connection IF 40 is USB standard. As is well known, the USB cable includes four signal lines of GND, D +, D-, and Vbus. The Vbus line is a signal line that is pulled up to 5 V when the host computer 50 detects a USB connection. By detecting that the Vbus line has been pulled up to 5V, the external connection IF 40 can recognize the connection of the computer 50 and notifies the CPU 30 to that effect.

  In response to the connection notification from the external connection IF 40 (S 61), the CPU 30 instructs the disk access device 18 to read the UDF area of the recording medium 20 and store it in the transfer data area 66 of the memory 36.

  Subsequent operations of the video camera 10 in response to a request for data in the UDF area and a request for moving image data from the computer 50 are the same as in the case of the first embodiment, and thus description thereof is omitted.

  Before the computer 50 actually requests access to the recording medium 20, the data in the UDF area is pre-read into the memory 36, so the time from when the computer issues a read command until it acquires the data is shortened. And apparently the response speed becomes faster.

  In each of the embodiments described above, the data in the UDF area is shown as the file system management information of the recording medium 20, but it goes without saying that RDM may be added thereto. When the recording medium 20 employs a file system other than UDF, file system management information corresponding to the UDF area, for example, TOC (Table Of Contents) may be pre-read into the memory 36.

  Although USB is exemplified as the external connection interface, other digital interfaces such as IEEE1394 may be used.

It is a schematic block diagram of the first embodiment of the present invention. It is a schematic diagram which shows the memory map and data flow in recording mode. It is a schematic diagram which shows the memory map and data flow in reproduction | regeneration mode. It is a schematic diagram which shows the memory map and data flow in an external connection mode. 2 shows a format example of a recording medium 20. It is an example of a procedure for reading moving image data according to a USB mass storage ATAPI protocol. It is an example of a procedure for reading file system management information by a USB mass storage ATAPI protocol. It is an operation | movement flowchart in external connection mode. 4 is an operation flowchart of the video camera 10 in response to a read request from the computer 50. It is explanatory drawing of USB connection and a USB cable. 4 is a flowchart of an operation for prefetching a UDF area of a recording medium 20 in response to USB connection detection.

Explanation of symbols

10: video camera 12: imaging unit 14: camera signal processing device 16: encoding processing device 18: disk access device 20: recording medium 22: LCD control device 24: liquid crystal display device (LCD)
26: Decoding processing device 28: Video output terminal 30: CPU
32: ROM
34: RAM
36: Memory 38: Memory control device 40: External connection interface (IF)
42: Operation unit 44: Bus 50: Computer

Claims (4)

Input means for inputting an image signal,
Memory,
Encodes the input image signal by the pre-Symbol input means, encoding means for storing the image signals encoded in said memory,
The encoded image signal is read from the memory, the read image signal is recorded on a recording medium according to a file system , the encoded image signal is reproduced from the recording medium, and the reproduced image signal is Access means for storing in said memory ;
Reads the image signal the coded from the memory, a decoding hand stage you decode the image signal read,
And connection means for connecting with external equipment,
A plurality of modes including a recording mode in which the access means records an image signal, a reproduction mode in which the access means reproduces an image signal, and an external connection mode in which the external device accesses the recording medium via the connection means An instruction means for instructing any of the above,
Means for changing the setting of the memory according to the mode instructed by the instructing means, wherein in the recording mode and the reproduction mode, a predetermined storage area in the memory is stored in the encoded image signal; Control means for setting the predetermined area in the memory as a storage area for management information of the file system in the external connection mode ,
The control means controls the encoding means to store the encoded image signal in the predetermined storage area in the recording mode, and the access means controls the predetermined storage area in the reproduction mode. So that the image signal reproduced from the recording medium is stored, and in the external connection mode, the access means stores the management information reproduced from the recording medium in the predetermined storage area of the memory. Controlling, when the management information is requested from the external device, the management information is read from the predetermined storage area in the memory and transmitted to the external device by the connection means apparatus. In the external connection mode, when the image signal is requested from the external device, the control unit reproduces the image signal from the recording medium by the access unit and transmits the image signal to the external device by the connection unit. The recording / reproducing apparatus according to claim 1, wherein: An input means for inputting an image signal;
Memory,
Encoding means for encoding the image signal input by the input means, and storing the encoded image signal in the memory;
Access means for reading the encoded image signal from the memory and recording the read image signal on a recording medium according to a file system;
A connection means for connecting to an external device;
An instruction means for instructing one of a plurality of modes including a recording mode in which the access means records an image signal and an external connection mode in which the external device accesses the recording medium via the connection means;
Means for changing the setting of the memory in accordance with the mode instructed by the instructing means, wherein in the recording mode, a predetermined storage area in the memory is used as a storage area for the encoded image signal; Control means for setting and setting the predetermined area in the memory as a storage area for management information of the file system in the external connection mode
And
The control means controls the encoding means to store the encoded image signal in the predetermined storage area in the memory in the recording mode, and in the external connection mode, the access means The management information reproduced from the recording medium is controlled to be stored in the predetermined storage area. When the management information is requested from the external device, the management information is stored in the memory from the predetermined storage area. Read and send to the external device by the connection means
A recording apparatus. Memory,
An access means for reproducing an encoded image signal from a recording medium according to a file system and storing the reproduced image signal in the memory;
Decoding means for reading the encoded image signal from the memory and decoding the read image signal;
A connection means for connecting to an external device;
An instruction means for instructing one of a plurality of modes including a reproduction mode in which the access means reproduces an image signal and an external connection mode in which the external device accesses the recording medium via the connection means;
Means for changing the setting of the memory in accordance with the mode instructed by the instructing means, wherein a predetermined storage area in the memory is used as a storage area for the encoded image signal in the reproduction mode; Control means for setting and setting the predetermined area in the memory as a storage area for management information of the file system in the external connection mode
And
The control means controls the access means to store the image signal reproduced from the recording medium in the predetermined storage area in the memory in the reproduction mode, and in the external connection mode, the access means The management information reproduced from the recording medium is controlled to be stored in the predetermined storage area in the memory, and when there is a request for the management information from the external device, from the predetermined storage area in the memory Read the management information and send it to the external device by the connection means
A reproducing apparatus characterized by that.

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