JP2011035836A - Apparatus and method for recording video - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a video recording apparatus and video recording method for recording obtained material while maintaining its correctness, while avoiding an increase in the scale of the apparatus and an increase in cost and without limiting apparatus functions. <P>SOLUTION: The same video material is encoded by encoders 10-1 and 10-2, respectively, and a check sum is added in the unit of a GOP. Buffers 21-1, 21-2 temporarily hold material data from the encoders 10-1, 10-2 and output the material data to an inspection device 23. The inspection device 23 refers to the check sum of the material data from the buffers 21-1, 21-2, determines whether an encode error occurs, and switches the material data to be derived in the unit of a GOP when the error occurs. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a video recording apparatus and a video recording method for recording captured video material, for example.

  In the conventional video recording apparatus, in order to maintain the legitimacy of the video material to be recorded, the recording process is duplicated (for example, refer to Patent Documents 1 and 2). As a conventional duplex system, for example, there are the following two methods.

  One is a method of duplicating recording processing by operating an active video server and a standby video server. Each video server includes an encoder and a storage, and encodes the input video material and records it in the storage. At this time, the material data recorded in each video server is the same. However, this method has a problem that redundancy cannot be maintained in each system. In addition, since a video server must be prepared for each system, there is a problem that the volume and cost of the entire device increase.

  The other is a method of duplicating recording processing by installing two encoders in one video server. At this time, the video material input to each encoder is simultaneously encoded by each encoder and recorded in the storage of the video server. At this time, two identical material data are recorded in the storage. However, in this method, it is necessary to store two data for one video material in order to maintain redundancy. Therefore, there is a problem that consumption of storage resources is doubled. In addition, due to the characteristics of the video server, there is a limit to the number of simultaneous inputs, so there is a problem that the number of recording channels is halved if one video material is saved as two data.

  Furthermore, in the above duplexing method, when an error is detected when one material data is decoded and output, switching is made to output the other material data. However, in this method of switching the output system, even if an error occurs in the encoded data, the data error cannot be detected until the material data is decoded. Therefore, there is a problem that the legitimacy of the material data cannot be obtained until the reproduction process is performed.

Japanese Patent Laid-Open No. 9-74559 JP 2006-108875 A

  As described above, in the conventional video recording device, there are problems that the size and cost of the device are increased and the number of inputs to the storage is limited in order to maintain the legitimacy of the video material to be recorded. It was. In addition, even if there is an error during the encoding of the material data, the error cannot be detected until decoding, so there was a problem that the legitimacy of the recorded material data could not be obtained until the playback process. .

  The present invention has been made for the above circumstances, and its purpose is to avoid the increase in size and cost of the apparatus, and to record the acquired material while maintaining its validity without limiting the function of the apparatus. It is an object of the present invention to provide a video recording apparatus and a video recording method capable of performing the above.

  In order to achieve the above object, the video recording apparatuses according to the present invention each acquire the same video material, encode the video material into material data in a preset data unit, and perform an abnormality in the encoding process. A plurality of encoding units that add error detection codes for detecting each of the material data, and each of the plurality of encoding units is connected to one of the plurality of encoding units, and the material data from the encoding unit is temporarily A plurality of holding units that hold and output, and a plurality of material data output from the plurality of holding units, and the material data by referring to the error detection code added to the material data of the plurality of systems A derivation unit for selectively deriving material data of a system determined to have no abnormality among the received material data; ; And a recording unit for recording the material data from the deriving unit.

  Further, the video recording method according to the present invention encodes the same video material input to a plurality of systems into material data in a preset data unit, and detects an error in the encoding process. A detection code is added to each of the plurality of systems of material data, the plurality of systems of material data to which the error detection code is added is temporarily held and output, and the errors added to the plurality of systems of material data By referring to the detection code, it is determined whether or not there is an abnormality that has occurred in the encoding process in the material data, and among the material data of the plurality of systems, the material data of the system that is determined to have no abnormality It selectively derives and records the derived material data.

  In the video recording apparatus and video recording method configured as described above, the same video material respectively input by a plurality of encoding units is encoded in preset data units, and an error detection code is added to the encoded material data. Then, the error detection code added to the material data by the deriving unit is referred to determine whether or not an error has occurred during the encoding process, and the material data in which no error has occurred is derived to the recording unit. As a result, only one system of material data in which no error has occurred is recorded in the recording unit.

  According to the present invention, it is possible to avoid the increase in size and cost of the apparatus, and to record the acquired material while maintaining its legitimacy without limiting the function of the apparatus, and the video recording A method can be provided.

It is a block diagram which shows the function structure of the video recording apparatus which concerns on one Embodiment of this invention. It is a block diagram which shows the function structure of the inspection apparatus of FIG. It is a sequence diagram which shows the recording process of the video recording device of FIG.

  Hereinafter, embodiments of a video recording apparatus according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a functional configuration of a video recording apparatus according to an embodiment of the present invention. The video recording device is, for example, a video server, and includes encoders 10-1 and 10-2, a memory controller 20, and a storage 30.

  The encoders 10-1 and 10-2 receive video material captured by a camera or the like, and set the received video material in advance by an encoding method such as MPEG (Moving Picture Experts Group) and JPEG (Joint Photographic Experts Group). Encode in the specified data unit. At this time, the encoders 10-1 and 10-2 receive a synchronization signal such as a clock signal, and encode the video material in frame synchronization with the synchronization signal. As a result, the encoded material data is output from the encoders 10-1 and 10-2 at the same timing. Further, the material data encoded by the encoders 10-1 and 10-2 can be exchanged in units of the above data. In the following, a case where encoding is performed using MPEG as an example will be described.

  The encoders 10-1 and 10-2 encode a video material, and then add a checksum that is an error detection code in GOP (Group Of Picture) units. When the checksum is added to the material data, the encoders 10-1 and 10-2 transfer the GOP-unit material data after the checksum is added to the memory controller 20.

  The memory controller 20 includes buffers 21-1 and 21-2, a connection monitoring unit 22, and an inspection device 23. The memory controller 20 is connected to the encoders 10-1 and 10-2 via an IP network such as Ethernet (registered trademark), and receives material data transferred from the encoders 10-1 and 10-2. Note that the present invention can be similarly implemented even when the encoders 10-1 and 10-2 and the memory controller 20 are connected via a network switch or the like.

  The buffer 21-1 receives the material data from the encoder 10-1, and holds it until the storage capacity of the material data reaches 1 GOP. The buffer 21-2 receives the material data from the encoder 10-2 and holds it until the storage capacity of the material data becomes 1 GOP. The buffers 21-1 and 21-2 receive the synchronization signal, and when the 1 GOP material data is accumulated, according to this synchronization signal, the 1 GOP material data is synchronized with each other and output to the inspection device 23.

  The connection monitoring unit 22 monitors material data from the encoders 10-1 and 10-2. When the material data is not supplied from the encoders 10-1 and 10-2, the connection monitoring unit 22 considers that there is an abnormality in the connection between the encoder to which the material data is not supplied and the memory controller 20. The connection monitoring unit 22 outputs the accumulated material data for 1 GOP to the buffer to which the material data is supplied without waiting for the material data to be accumulated in the buffer to which the material data is not supplied. Give instructions to do.

  FIG. 2 is a block diagram showing a functional configuration of the inspection apparatus 23 according to an embodiment of the present invention. 2 includes detection units 231-1 and 231-2, a memory 232, a determination unit 233, a control unit 234, and a switching unit 235. The detection units 231-1 and 231-2 detect the checksum attached to the material data supplied from the buffers 21-1 and 21-2 in GOP units, and output the detected checksum to the determination unit 233.

  In the memory 232, a checksum when the video material is correctly encoded is recorded in advance. The determination unit 233 compares the checksum from the detection units 231-1 and 231-2 with the checksum recorded in the memory 232, thereby encoding the material data from the buffers 21-1 and 211-2. It is determined whether or not this has occurred. At this time, when the checksum added to the material data is the same as the checksum of the memory 232, the determination unit 233 determines that no encoding error has occurred in the material data. Judge that an encoding error has occurred. Determination unit 233 outputs the determination result to control unit 234.

  The control unit 234 selectively controls one of the material data output from the buffers 21-1 and 21-2 by controlling the switching unit 235 based on the determination result of the determination unit 233. Derived to Specifically, when it is determined that an encoding error has occurred in the material data derived to the storage 30, the control unit 234 switches to the switching unit 235 to derive the material data from the other buffer. Take control. In addition, the control unit 234 gives an instruction to the buffer holding the material data so as to discard the material data in which the encoding error has occurred.

  In addition, when an encoding error occurs in the material data of both systems, the control unit 234 requests the recording stop by notifying the user of the video recording apparatus of the recording error.

  The storage 30 records the material data derived from the inspection device 23 as a material file.

  Next, the operation in the above configuration will be described.

  FIG. 3 is a sequence diagram showing recording processing of the video recording apparatus according to the embodiment of the present invention. Here, the transmission system using the encoder 10-1 and the buffer 21-1 is the active system, and the transmission system using the encoder 10-2 and the buffer 21-2 is the standby system, and an encoding error occurs in the material data of the active system. The case will be described as an example.

  The encoder 10-1 and the encoder 10-2 output the material data A and material data B in 1 GOP units to which a checksum is added in synchronization with each other. The material data A from the encoder 10-1 is transmitted to the buffer 21-1 (S31) and held in the buffer 21-1 until 1 GOP is accumulated. The material data B from the encoder 10-2 is transmitted to the buffer 21-2 (S32) and held in the buffer 21-2 until 1 GOP is accumulated.

  When the material data A and B are stored in 1 GOP, the buffers 21-1 and 21-2 synchronize the material data A for 1 GOP and the material data B for 1 GOP with each other and output them to the inspection apparatus 23 (S 33, S34). The inspection device 23 detects the checksum of the material data A and B, and determines whether or not an encoding error has occurred based on this checksum. The inspection device 23 derives the active material data A in a normal state. However, when an encoding error occurs in the material data A, the inspection device 23 switches the derivation to the material data B on a GOP basis. Then, the inspection device 23 discards the material data A in which the encoding error has occurred in the buffer 21-1. The storage 30 records the derivation-switched material data B following the material data A (S35).

  As described above, in the video recording apparatus according to the above-described embodiment, the same video material is encoded by the encoders 10-1 and 10-2, and a checksum is added in GOP units. The inspection device 23 checks the occurrence of an error by referring to the checksum. When an error occurs, the derived material data is switched in units of GOPs. As a result, only material data in which no error has occurred can be recorded in the storage 30. In addition, since the derived material data is switched in units of GOPs, the material data can be seamlessly recorded in the storage 30 even when the material data is switched due to the occurrence of an encoding error. Further, since there is no need to prepare two video servers as in the prior art, it is possible to avoid an increase in size and cost of the apparatus.

  In the video recording apparatus according to the above-described embodiment, only one system of material data is derived to the storage 30, and one material data is recorded in the storage 30. As a result, the number of inputs to the storage 30 can be reduced, and storage resources can be saved. That is, in order to maintain the legitimacy of the material data, the performance of the video recording apparatus is not degraded.

  Therefore, the video processing apparatus according to the present invention can record the acquired material while maintaining its validity without restricting the size and cost of the apparatus and without limiting the function of the apparatus.

  The present invention is not limited to the above-described embodiment. For example, in the above-described embodiment, the example in which the encoder encodes using MPEG and adds the checksum in GOP units has been described. However, the present invention is not limited to this example. For example, when the encoding method is JPEG, a checksum is added for each frame data unit. When an encoding error occurs in the encoded material data, the same can be implemented by switching the derived material data in units of frame data by the memory controller. When the codec is MPEG, it can be implemented without depending on the codec as long as it is an independent data unit in the material data, such as GOP data unit and JPEG is a frame unit.

  In the above embodiment, an example in which a checksum is employed as an error detection code has been described. However, the error detection code employed in the present invention is not limited to a checksum.

  In the above embodiment, the encoders 10-1 and 10-2 and the memory controller 20 are connected by the IP network. However, the encoders 10-1 and 10-2 and the memory controller 20 are connected by a bus. Even if it is connected, it can be implemented.

  In the above embodiment, the example in which the transmission system of the material data is two systems has been described, but the present invention is not limited to two systems.

  Furthermore, the present invention can be embodied by modifying the constituent elements without departing from the spirit of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment.

10-1, 10-2 ... encoder 20 ... memory controllers 21-1, 21-2 ... buffer 22 ... connection monitoring unit 23 ... inspection devices 231-1, 231-2 ... detection unit 232 ... memory 233 ... determination unit 234 ... Control unit 235 ... switching unit 30 ... storage

Claims (9)

Each acquires the same video material, encodes the video material into material data in a preset data unit, and adds an error detection code for detecting abnormality in the encoding process for each material data A plurality of encoding units,
A plurality of holding units each connected to one of the plurality of encoding units, and temporarily holding and outputting the material data from the encoding unit;
There is an abnormality that has occurred in the encoding process in the material data by receiving the material data of a plurality of systems output from the plurality of holding units and referring to the error detection code added to the material data of the systems A derivation unit that selectively derives material data of a system that has been determined that there is no abnormality among the received material data;
A video recording apparatus comprising: a recording unit that records material data from the derivation unit. The video recording apparatus according to claim 1, wherein when the abnormality occurs in the material data of the derived system, the derivation unit switches the derivation to material data of another system in which no abnormality has occurred. The video recording apparatus according to claim 1, wherein the error detection code is a checksum. The encoding unit encodes the video material using MPEG (Moving Picture Experts Group), and adds the error detection code to the encoded GOP unit material data. The video recording device described. The connection between the plurality of encoding units and the plurality of holding units is monitored, and when abnormality occurs in the connection, material data is output only from the holding unit of the system in which the connection abnormality does not occur The video recording apparatus according to claim 1, further comprising a monitoring unit. Encode the same video material input to multiple systems into material data in preset data units,
An error detection code for detecting an abnormality in the encoding process is added for each material data of the plurality of systems,
Temporarily holding and outputting a plurality of material data to which the error detection code is added,
By referring to the error detection code added to the material data of the plurality of systems, it is determined whether there is an abnormality that has occurred in the encoding process in the material data,
Of the material data of the plurality of systems, selectively derive the material data of the system determined to have no abnormality,
A video recording method, wherein the derived material data is recorded. 7. The video recording method according to claim 6, wherein when the abnormality occurs in the material data of the derived system, the derivation is switched to material data of another system in which no abnormality has occurred. The video recording method according to claim 6, wherein the error detection code is a checksum. 7. The video recording method according to claim 6, wherein the video material is encoded using MPEG (Moving Picture Experts Group), and the error detection code is added to the encoded GOP unit material data.

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