JP2013062647A - Image recording and reproducing apparatus, image recording method of the same, and program of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To continue recording operation even if image signals etc. are disturbed or interrupted during recording (during encoding) or immediately before the start of recording, without using special hardware.SOLUTION: An image recording and reproducing apparatus is configured to code and record images. On this purpose, the apparatus comprises coding means which receives an image input signal and outputs coded data obtained by coding the image input signal. The apparatus also comprises control means which controls the operation of the coding means, receives the encoded data from the coding means, and outputs the coded data. If the image input signal is not inputted normally, the control means replaces the coded data to be outputted with prepared dummy data based on the same coding method as a coding method which the coding means uses, and outputs the dummy data.

Description

  Embodiments described herein relate generally to a video recording / playback apparatus, a video recording method thereof, and a program thereof.

  2. Description of the Related Art Conventionally, broadcast stations have recorded and stored captured video in a video recording device called a video server. When video is recorded on a video server, it is generally encoded by a compression encoding method such as MPEG2 in order to reduce the information amount of the baseband signal. Since encoding by MPEG2 is performed in units of frames, it is assumed that a stable video signal, synchronization signal, and clock are supplied to the recording processing unit. If these are unstable, there is a risk of causing problems such as operation stop.

  For example, if the video signal is disturbed during recording (during encoding) and the synchronization signal or clock is disturbed, the recording stops. Also, if the video signal becomes unstable immediately before the start of recording, the angle of view (effective area) to be encoded is not fixed, so that the image is recorded with the angle of view shifted even after the video signal is stabilized. In order to avoid these problems, special hardware such as a synchronization protection circuit, a clock stabilization circuit, or a synchronization generation circuit using a reference signal must be prepared as a mechanism to protect the synchronization signal or stabilize the clock. There are many. Alternatively, there is a technique for dealing with the video playback side.

JP 2001-36905 A

  However, since these mechanisms are configured by dedicated hardware, there are problems of whether or not they can be mounted and problems of manufacturing costs. There is also a mechanism for inputting a reference signal as a stable synchronization / clock source and generating the synchronization / clock from this reference signal, but this also requires a dedicated synchronization / clock generation circuit. There is a restriction that the frequency / phase relationship between the video signal and the video signal must be fixed. Further, when dealing with the playback device side, it is necessary to provide the playback device itself with a special function.

  The problem to be solved by the present invention is that the recording operation can be continued even if the video signal is disturbed or interrupted during recording (encoding) or just before recording without using special hardware. It is an object of the present invention to provide a video recording / playback apparatus, a video recording method thereof, and a program thereof that can avoid the above-described mounting problems, manufacturing cost problems, and constraint problems.

  The video recording / playback apparatus according to the embodiment is a video recording / playback apparatus that records and records video. For this reason, an encoding means for receiving a video input signal and outputting encoded data obtained by encoding the video input signal is provided. A control unit is provided to control the operation of the encoding unit and to receive and output encoded data from the encoding unit. When the video input signal is not normally input, the control unit replaces the encoded data to be output with dummy data prepared in advance that conforms to the same encoding method used by the encoding unit. Output.

FIG. 1 is a block diagram illustrating a main configuration for encoding and recording video in the video server of the embodiment. FIG. 2 is a diagram showing a basic configuration of a recording processing unit mounted on the video server. FIG. 3 is a diagram illustrating a configuration example of a recording processing unit using dedicated hardware. FIG. 4 is a diagram illustrating a circuit configuration including the recording processing unit and the CPU according to the embodiment. FIG. 5 is a flowchart showing an operation flow of the CPU in the present embodiment. FIG. 6 is a diagram illustrating a case where the SDI input signal is interrupted before the start of encoding. FIG. 7 is a diagram illustrating a case where the SDI input signal is interrupted during encoding.

(Main configuration of video server)
First, a description will be given of a main configuration for encoding and recording video in a video server (video recording / playback apparatus) according to an embodiment. FIG. 1 is a block diagram showing the main configuration. In FIG. 1, the portion related to reproduction is omitted.

  The video server 10 of this embodiment includes a recording processing unit 300 that compresses and encodes an SDI (Serial Digital Interface) input signal 301 from a video signal supply source such as a VTR or a video camera, an HDD that stores encoded data 310, and the like. The storage 20 and the CPU 307 that obtains the encoded data 306 after compression encoding by the recording processing unit 300 and outputs the encoded data 310 to the storage 20 are roughly configured. The video data stored in the video server 10 is output and displayed on a monitor, edited by an image processing device, or used for broadcasting, for example. Note that each recording processing unit in the recording processing unit 300 and a configuration example using a dedicated hardware as a basic configuration and a reference example to be described later conforms to MPEG2 for baseband video data included in the SDI input signal 301. It is assumed that compression encoding is performed.

  Hereinafter, prior to detailed description of the recording processing unit 300 and the CPU 307 in the present embodiment, a general basic configuration and a reference example of the recording processing unit will be described.

(Basic configuration of the recording processing unit)
First, a basic configuration of a general recording processing unit mounted on the video server will be described. FIG. 2 is a diagram showing a basic configuration of a recording processing unit mounted on the video server.

  The recording processing unit 100 shown as a basic configuration includes a serial-parallel conversion circuit 102 and an encoding circuit 105, and receives an SDI input signal 101 and outputs encoded data 106. The SDI input signal 101 is a digital high-speed serial signal and includes data such as its clock along with video data in accordance with the SDI standard. The SDI input signal 101 is first separated into video data 103 and a clock signal 104 converted into a parallel signal by the serial / parallel conversion circuit 102, and this is input to the encoding circuit 105. The video data 103 has synchronization information for matching timing called TRS (Timing Reference Signal) and always sends time information. The encoding circuit 105 performs compression encoding conforming to the MPEG2 standard on the video data 103 and outputs it as encoded data 106.

  MPEG2 is an extremely strict standard regarding the number of frames and time management for buffer amount management, so the synchronization information and clock play an important role. Therefore, the encoding circuit 105 performs time management using the separated synchronization information (not shown) and the clock signal 104. When the SDI input signal 101 is disconnected, the video data 103 and the clock signal 104 are disturbed or no signal is present. However, the abnormality of these signals important for time management is encoded. This leads to abnormal operation and stop of the circuit 105.

(Configuration example of recording processing unit using dedicated hardware)
Here, for reference, a configuration example of a recording processing unit using dedicated hardware for dealing with the above problem will be described with reference to FIG. FIG. 3 is a diagram illustrating a configuration example of a recording processing unit using dedicated hardware.

  In order to avoid the stop of encoding due to disconnection or the like of the SDI input signal 201, generally, as shown in FIG. 3, the recording processing unit 200 uses a synchronization circuit 205 as dedicated hardware. The serial / parallel conversion circuit 202 and the encoding circuit 208 correspond to the serial / parallel conversion circuit 102 and the encoding circuit 105 in the basic configuration described above, respectively.

  As preprocessing of the encoding circuit 208, an independent synchronization / clock signal 210 generated independently of the SDI input signal 201 is input to the synchronization circuit 205, and the video input signal 203 is The independent synchronization / clock signal 210 is converted into a video input signal 206 as a reference. On the other hand, the encoding circuit 208 also receives the clock signal 207 from the independent synchronization / clock signal 210 generated independently of the SDI input signal 201, performs encoding based on this, and outputs encoded data 209. To do.

  If the SDI input signal 201 is interrupted and the video input signal 203 and the clock signal 204 are interrupted, the synchronization circuit 205 generates and outputs a black signal based on the independent synchronization / clock signal 210. As a result, the input to the encoding circuit 208 is not interrupted and the signal is not disturbed, so that the encoding circuit 208 can continue a stable operation.

  However, such a circuit configuration requires dedicated hardware called the synchronization circuit 205, which leads to an increase in manufacturing cost.

(Configuration consisting of recording processing unit and CPU of this embodiment)
Therefore, the present embodiment addresses the problem that such dedicated hardware is not used and the encoding process in the encoding circuit cannot be continued. FIG. 4 is a diagram illustrating a circuit configuration including a recording processing unit and a CPU according to the present embodiment.

  In the recording processing unit 300 of the present embodiment, the operation between the serial / parallel conversion circuit 302 and the encoding circuit 305 is the same as that in the basic configuration described above. The SDI input signal 301 is first separated into video data 303 and a clock signal 304 converted into parallel signals by the serial / parallel conversion circuit 302, which are input to the encoding circuit 305. An encoding circuit 305 performs compression encoding conforming to the MPEG2 standard on the video data 303 and outputs it as encoded data 306. In the present embodiment, the differences from the basic configuration are as follows.

  The serial / parallel conversion circuit 302 detects stop / disconnection of the SDI input signal 301 and sends it as an interrupt signal to the CPU 307 that controls the encoding circuit 305 and the like as an input detection signal 308. At this time, the CPU 307 performs control of the recording processing unit 300 or predetermined control according to the encoding control signal 311 from the external device.

  When the CPU 307 is notified of the signal disconnection by the input detection signal 308 during encoding, the CPU 307 determines that the subsequent operation of the encoding circuit 305 cannot be guaranteed in the interrupt processing, and the encoding circuit control signal 309 determines the encoding circuit. The operation stop at 305 is performed.

  While the encoding circuit 305 is stopped, output of the encoded data 306 from the encoding circuit 305 is stopped. During this time, the CPU 307 prepares in advance in a memory or storage 20 (not shown). The dummy data previously used is used, and this dummy data is output as encoded data 310. This dummy data conforms to the same encoding method used by the encoding circuit 305 (here, MPEG2), and is, for example, MPEG2 data consisting of a black image.

  When the SDI input signal 301 is detected again by the input detection signal 308, the CPU 307 starts the operation of the encoding circuit 305 again by the encoding circuit control signal 309.

  Since these series of processes are completed and executed inside the video server 10, when viewed from the outside of the apparatus, it is not noticed that the encoding circuit 305 is stopped, and the encoding process seems to be continued. That is, even when the SDI input signal 301 is stopped during encoding, the output of the encoded data 310 is not stopped and continuous encoded data 310 is obtained.

(CPU operation)
Next, control of the encoding circuit 305 of the CPU 307 according to this embodiment will be described with reference to FIGS. FIG. 5 is a flowchart showing an operation flow of the CPU 307 in the present embodiment. FIG. 6 is a diagram illustrating a case where the SDI input signal is interrupted before the start of encoding, and FIG. 7 is a diagram illustrating a case where the SDI input signal is interrupted during encoding.

(When SDI input signal is interrupted before encoding starts: Fig. 6)
When the CPU 307 of the video server 10 receives an encoding start command as the encoding control signal 311 from the external device, the CPU 307 confirms the presence or absence of the SDI input signal 301 (step S401). This can be confirmed by the input detection signal 308 from the serial / parallel conversion circuit 302. Also, the presence / absence of the SDI input signal 301 is determined by the serial / parallel conversion circuit 302 based on whether or not the input signal is a normal code conforming to the SDI standard.

  If the SDI input signal 301 is not present (or not normal) at the start of encoding, the encoding circuit 305 is not operated and is output as encoded data 310 using dummy data prepared in advance (step S407).

  Thereafter, for each frame, it is confirmed whether the encoding is continued (that is, there is no instruction to stop encoding from the external device) (step S408). If it is continued, the SDI input signal 301 is further confirmed (step S408). S409). When the SDI input signal 301 is detected, the encoding circuit control signal 309 causes the encoding circuit 305 to start encoding processing (step S402).

  After the start of the encoding process, the replacement of the output (encoded data 310) with dummy data is stopped, and the encoded data 306 output from the encoding circuit 305 is acquired and used as the output (encoded data 310). (Step S403). However, according to the MPEG2 standard, the dummy data and the output from the encoding circuit cannot be switched at arbitrary timing, so the dummy data length (for example, GOP) is switched so as to be switched at the GOP setting boundary (point where the I frame starts). (Group Of Picture) N times (N = 1, 2, 3,...)) And the timing for starting encoding (when “the SDI input signal is interrupted during encoding” described below) The same).

  By controlling as described above, encoding fails in the conventional technique. However, in this embodiment, after receiving an instruction to start encoding from an external device, it is possible to output encoded data and continue it.

(When SDI input signal is interrupted during encoding: Fig. 7)
Even during the encoding after step S403, the continuation of encoding is confirmed for each frame (step S404), and if it is continued, the SDI input signal 301 is further confirmed (step S405). At this time, if there is an SDI input signal 301 (if it is normally input), the process returns to step S403, and the encoding is continued, and the encoded data output from the encoding circuit is acquired and used as an output. .

  If the SDI input signal 301 is interrupted (there is no SDI input signal or is not normal at this time), the operation of the encoding circuit 305 is stopped by the encoding circuit control signal 309 (step S406).

  In step S406, the operation of the encoding circuit 305 is stopped, but since the encoding control from the outside that stops the operation of the encoding circuit 305 is continued, the encoded data 310 is dummy while the encoding circuit is stopped. Data replacement is performed, and the dummy data is output as encoded data 310 (step S407).

  Thereafter, the processing after step S408 described above is performed. If the continuation of encoding is confirmed in step S408 and it is determined that there is no SDI input signal, the process returns to step S407 to continue outputting dummy data. On the other hand, when the SDI input signal 301 is detected again in step S409, the operation of the encoding circuit 305 is started again (step S402), and the processing after step S403 is executed. If it is confirmed in step S404 that the process is completed, the operation of the encoding circuit 305 is stopped in step S410 and the process is terminated. If it is confirmed in step S408 that the process is completed, the operation of the encoding circuit 305 is stopped at this time, and the process is terminated as it is.

  By controlling as described above, in the conventional technique, encoding stops in the middle, but in this embodiment, encoding can be continued.

  As described above, the video server 10 of the present embodiment does not require special hardware such as the above-described synchronization circuit 205 in the recording processing unit 300, and the video signal is recorded during recording or immediately before the recording starts. Even when the image is disturbed or interrupted, stable encoding processing can be continued. In addition, when the video input signal is disturbed or interrupted, the encoded data 310 that is finally output includes dummy data (for example, a black image). This is normal MPEG2 data, and this normal (unbroken) data is accumulated in the storage 20. Therefore, even if a playback device can decode data encoded in conformity with MPEG2, data stored in the storage 20 can be normally played back by normal processing even if the playback device is a general playback device. Can do.

  In the above embodiment, the video input signal input to the video server 10 is not limited to the SDI input signal 301 compliant with the SDI standard, but may be a serial video input signal by other methods. In the above embodiment, encoding by the encoding circuit 305 and control by the CPU 307 have been described for MPEG2, but the present invention is not limited to this, and other encoding methods (for example, MPEG1, MPEG4, etc.) are used. Even if it exists, it can cope with the same control.

  A program executed by the CPU 307 is stored in advance in a storage unit such as an HDD or a ROM (not shown) such as the storage 20 provided in the video server 10. The program is loaded into a RAM (not shown) serving as a main storage device of the CPU 307 and executed by the CPU 307, whereby the above-described control is performed.

  The program may be provided as a file in an installable or executable format recorded on a computer-readable recording medium such as a CD-ROM, a floppy (registered trademark) disk (FD), or a DVD. Alternatively, it may be configured to be provided by being stored on a computer connected to a network such as the Internet and downloaded via the network.

  As mentioned above, although embodiment of this invention was described, this embodiment is shown as an example and is not intending limiting the range of invention. The novel embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. Further, this embodiment and its modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 10 Video server 20 Storage 100, 200, 300 Recording process part 102, 202, 302 Serial parallel conversion circuit 105, 208, 305 Coding circuit 205 Synchronization circuit 307 CPU

Claims (8)

In a video recording / playback device that records and records video,
Encoding means for receiving a video input signal and outputting encoded data obtained by encoding the video input signal;
Control means for controlling the operation of the encoding means, and receiving and outputting the encoded data,
The control means provides dummy data prepared in advance in accordance with the same encoding method as the encoding method used by the encoding means for outputting the encoded data when the video input signal is not normally input. Video recording and playback device to replace with.   2. The video recording / reproducing apparatus according to claim 1, wherein the control unit stops the encoding by the encoding unit when the video input signal is not normally input during encoding by the encoding unit.   The control means restarts the encoding by the encoding means and outputs the encoded data by the encoding means when the video input signal changes from a state where it is not normally input to a state where it is normally input The video recording / reproducing apparatus according to claim 2.   The control means starts video recording by outputting the dummy data without starting encoding by the encoding means when the video input signal is not normally input immediately before starting video recording. The video recording / reproducing apparatus according to any one of claims 1 to 3.   The control means starts encoding by the encoding means and outputs encoded data by the encoding means when the video input signal changes from a state where it is not normally input to a state where it is normally input The video recording / reproducing apparatus according to claim 4, wherein video recording is continued.   6. The video recording / reproducing apparatus according to claim 1, further comprising storage means for storing encoded data output by the control means. A video recording method in a video recording / playback apparatus for encoding and recording video,
Encoding the video input signal to be encoded by the encoding means of the video recording / playback apparatus, and outputting encoded data obtained by encoding the video input signal;
Receiving and outputting the encoded data by the encoding means;
When the video input signal is not normally input, replacing the encoded data to be output with dummy data prepared in advance that conforms to the same encoding scheme as the encoding scheme used by the encoding means;
Video recording method including A program to be executed by a computer included in a video recording / playback apparatus for encoding and recording video,
Encoding the video input signal to be encoded by the encoding means of the video recording / playback apparatus, and outputting encoded data obtained by encoding the video input signal;
Receiving and outputting the encoded data by the encoding means;
When the video input signal is not normally input, replacing the encoded data to be output with dummy data prepared in advance that conforms to the same encoding scheme as the encoding scheme used by the encoding means;
A program that describes the procedure including

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