JP2011008525A - Information processing apparatus and video processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information processing apparatus for safely creating a file in which metadata and media data are successively arranged.SOLUTION: A multiplexing processing part 35 reads prescribed processing unit data from a plurality of input media data 31 and 32, and generates a chunk obtained by multiplexing the read data. A metadata generation part 38 generates the metadata corresponding to the generated chunk. Also, a local encryption part 36 encrypts the chunk by using a local key, and stores the encrypted chunk into an encryption buffer 33. In response to the completion of the generation of the metadata corresponding to all the chunks, a local decryption part 37 decrypts the encrypted chunk. A media encryption part 40 encrypts the decrypted chunk by using a title key created from a media key. A data storage part 41 stores into output media 34a, file in which the metadata are arranged before multimedia data configured of the chunk encrypted by using a title key.

Description

  The present invention relates to an information processing apparatus and a video processing method for converting the format of video content data.

  Multimedia data such as video data and audio data is distributed to users via a recording medium such as a DVD storing data and a network such as the Internet. Since multimedia data which is digital data can be easily copied without deterioration, authentication processing at the time of use, data encryption processing, and the like are performed from the viewpoint of copyright protection.

  Patent Document 1 discloses a data processing apparatus that performs copyright protection for object data distributed over a network. In this data processing apparatus, the object data is protected by encrypting the object data using the key data and distributing the stream data obtained by multiplexing the encrypted object data and the key data via the network. .

JP 2001-359070 A

  The data processing apparatus disclosed in Patent Literature 1 considers protecting multimedia data distributed via a network, but protects data in a memory or HDD in a computer that processes the multimedia data. This is not taken into consideration. If multimedia data before encryption processing or decrypted multimedia data is stored in a memory or HDD in a computer, the multimedia data may be read from the memory or HDD and copied.

  By the way, an MP4 (ISO / IEC 14496-12, ISO / IEC 14496-14, ISO / IEC 14496-15) file includes a moov for storing metadata and an mdat for storing multimedia data. When making this MP4 file compatible with streaming playback, moov needs to be placed ahead of mdat. This is because multimedia data is stored in mdat in units of chunks, and metadata indicating the position of the chunk in the file is stored in moov. In order to create the metadata (moov), the configuration of the chunks in the multimedia data (mdat) must be fixed, and as described above, the moov needs to be placed ahead of the mdat. is there. For this reason, the multimedia data (mdat) is buffered until the creation of metadata (moov) corresponding to all chunks is completed. Thus, the buffered multimedia data may be read from the buffer and duplicated.

  The present invention has been made in consideration of the above-described circumstances, and an object thereof is to provide an information processing apparatus and a video processing method capable of safely creating a file in which metadata and media data are sequentially arranged.

  In order to solve the above-described problems, an information processing apparatus according to the present invention includes a multiplexing unit that generates multiplexed media data obtained by multiplexing a plurality of media data for each predetermined processing unit, and the multiplexed media data. Metadata generating means for generating corresponding metadata for each data of the predetermined processing unit, and local for generating first encrypted media data obtained by encrypting the data of the predetermined processing unit using first key data In response to the generation of all the metadata corresponding to the multiplexed media data, the encryption means, the buffering means for storing the first encrypted media data in a storage device, and the first encrypted media Decryption means for reading data from the storage device and decrypting the first encrypted media data, and the decrypted first encrypted metadata as a second key Media encryption means for generating second encrypted media data encrypted using a data, and data storage means for storing the metadata and the second encrypted media data in an external storage medium. It is characterized by.

  According to the present invention, a file in which metadata and media data are sequentially arranged can be created safely.

The perspective view which shows the example of the external appearance of the information processing apparatus which concerns on one Embodiment of this invention. FIG. 3 is an exemplary block diagram illustrating a configuration example of the information processing apparatus according to the embodiment. 2 is an exemplary block diagram showing an example of the functional configuration of a video processing application used in the information processing apparatus of the embodiment. FIG. The figure which shows the structural example of the video content data of the MP4 file format produced with the video processing application of FIG. 6 is an exemplary flowchart illustrating a procedure of video content data storage processing executed by the information processing apparatus of the embodiment.

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

  First, the configuration of an information processing apparatus according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. The information processing apparatus according to the present embodiment is realized by, for example, a notebook portable personal computer 10.

  The personal computer 10 can store video content data (audio visual content data) such as broadcast program data, video data input from an external device, and video data distributed through a network such as the Internet in an external storage medium. it can.

  FIG. 1 is a perspective view of the computer 10 with the display unit opened. The computer 10 includes a computer main body 11 and a display unit 12. The display unit 12 incorporates a display device including a TFT-LCD (Thin Film Transistor Liquid Crystal Display) 17.

  The display unit 12 is attached to the computer main body 11 so as to be rotatable between an open position where the upper surface of the computer main body 11 is exposed and a closed position covering the upper surface of the computer main body 11. The computer main body 11 has a thin box-shaped housing, and has a keyboard 13 on its upper surface, a power button 14 for powering on / off the computer 10, an input operation panel 15, a touch pad 16, and a speaker. 18A, 18B, etc. are arranged.

  On the right side of the computer main body 11, for example, an antenna terminal 19 for TV broadcasting is provided. Further, on the back surface of the computer main body 11, for example, an external display connection terminal corresponding to the HDMI (high-definition multimedia interface) standard is provided. The external display connection terminal is used to output video data (moving image data) included in video content data such as broadcast program data to an external display.

  Next, the system configuration of the computer 10 will be described with reference to FIG.

  As shown in FIG. 2, the computer 10 includes a CPU 101, a north bridge 102, a main memory 103, a south bridge 104, a graphics processing unit (GPU) 105, a video memory (VRAM) 105A, a sound controller 106, a BIOS- ROM 109, SD card slot 110, hard disk drive (HDD) 111, optical disk drive (ODD) 112, video processor 113, memory 113A, wired LAN controller 114, IEEE 1394 controller 115, wireless LAN controller 116, TV tuner 117, EEPROM 118, and An embedded controller / keyboard controller IC (EC / KBC) 119 is provided.

  The CPU 101 is a processor that controls the operation of the computer 10 and executes various application programs such as an operating system (OS) 201 and a video processing application program 202 that are loaded from the hard disk drive (HDD) 111 to the main memory 103. To do.

  The video processing application 202 is software for generating a multimedia data by multiplexing a plurality of media data (elementary streams) and storing an MP4 file including the multimedia data in an external storage medium. The video processing application program 202 includes, for example, moving image data of a broadcast program received by the TV tuner 117, moving image data recorded on a DVD or the like stored in the HDD 111 or ODD 112, a wired LAN controller 114, or a wireless LAN controller 116. Is stored in an external storage medium such as an SD card inserted into the SD card slot 110 as the above-described MP4 file.

  The CPU 101 also executes a BIOS (Basic Input Output System) stored in the BIOS-ROM 109. The BIOS is a program for hardware control.

  The north bridge 102 is a bridge device that connects the local bus of the CPU 101 and the south bridge 104. The north bridge 102 also includes a memory controller that controls access to the main memory 103. The north bridge 102 also has a function of executing communication with the GPU 105 via a PCI EXPRESS standard serial bus or the like.

  The GPU 105 is a display controller that controls the LCD 17 used as a display monitor of the computer 10. A display signal generated by the GPU 105 is sent to the LCD 17. The GPU 105 can also send a digital video signal to the external display device 1 via the HDMI control circuit 3 and the HDMI terminal 2.

  The HDMI terminal 2 is an external display connection terminal. The HDMI terminal 2 can send an uncompressed digital video signal and a digital audio signal to the external display device 1 such as a television with a single cable. The HDMI control circuit 3 is an interface for sending a digital video signal to the external display device 1 called an HDMI monitor via the HDMI terminal 2.

  The south bridge 104 controls each device on an LPC (Low Pin Count) bus and each device on a PCI (Peripheral Component Interconnect) bus. The south bridge 104 includes an IDE (Integrated Drive Electronics) controller for controlling the hard disk drive (HDD) 111 and the ODD 112. Further, the south bridge 104 has a function of executing communication with the sound controller 106.

  Furthermore, a video processor 113 is connected to the south bridge 104 via a PCI EXPRESS standard serial bus or the like.

  The sound controller 106 is a sound source device and outputs audio data to be reproduced to the speakers 18A and 18B or the HDMI control circuit 3.

  An IEEE 1394 controller 115, a wired LAN controller 114, a wireless LAN controller 116, a TV tuner 117, and the like are connected on the PCI bus.

  The IEEE 1394 controller 115 executes communication with an external device via an IEEE 1394 standard serial bus. The wired LAN controller 114 is a communication device that executes communication of, for example, IEEE 802.3 standard. The wireless LAN controller 116 is a wireless communication device that performs wireless communication of, for example, the IEEE 802.11 standard.

  The TV tuner 117 is a receiving device that receives broadcast program data broadcast by a television (TV) broadcast signal, and is connected to the antenna terminal 19. The TV tuner 117 is realized as a digital TV tuner capable of receiving digital broadcast program data such as terrestrial digital TV broadcast. The TV tuner 117 also has a function of capturing video data input from an external device.

  The embedded controller / keyboard controller IC (EC / KBC) 119 is a one-chip microcomputer in which an embedded controller for power management and a keyboard controller for controlling the keyboard (KB) 13 and the touch pad 16 are integrated. . The embedded controller / keyboard controller IC (EC / KBC) 119 has a function of powering on / off the computer 10 in accordance with the operation of the power button 14 by the user. Further, the embedded controller / keyboard controller IC (EC / KBC) 119 has a function of executing communication with the remote control unit interface 20.

  FIG. 3 is a block diagram showing the configuration of the video processing application program 202.

  As described above, the video processing application program 202 is distributed from moving image data of a broadcast program received by the TV tuner 117, moving image data recorded on a DVD or the like stored in the HDD 111 or the ODD 112, or a server on the Internet. Moving image data and the like can be stored in an external storage medium.

  The video processing application 202 multiplexes input media data 31 and 32 (elementary streams) to generate multimedia data, and MP4 file format video content data (audio visual content data) including the multimedia data. A process of storing in the output medium 34 is performed. This MP4 file is compatible with streaming playback.

  FIG. 4 shows a configuration example of video content data (MP4 file) in the MP4 file format created by the video processing application 202.

  As shown in FIG. 4, the MP4 file is composed of a set of data called boxes such as ftyp, moov, mdat and the like. Boxes are hierarchical, and another box can be stored in a box.

  ftyp is a box in which information on file compatibility is stored. ftyp is arranged at the head of the MP4 file. The video processing application 202 determines the encoding method of video data and audio data stored in the MP4 file based on the data described in ftyp.

  moov (MovieBox) is a box for storing metadata of the MP4 file. The moov includes a plurality of hierarchized boxes. The moov includes a trak that is a box in which header information of a track of video data or audio data is stored. Further, trak includes stco (ChunkOffsetBox) in which information indicating the head position of a chunk (chunk) of track data is described in the lower layer. In stco, as shown in FIG. 4, an offset value (absolute address) indicating the start position of the chunk on the file is described.

  mdat (MovieDataBox) is a box for storing video data and audio data itself. The compression-coded video data and audio data are alternately stored in mdat in units of chunks.

  The video processing application 202 corresponds to the position and size of the chunk of video data and audio data stored in mdat, and the frame stored in the chunk from the metadata described in a box such as stco included in the moov. Information such as data position and size, frame playback time, and playback time can be acquired.

  As described above, the MP4 file stores moov for storing metadata and mdat for storing multimedia data. Since the metadata moov can be created after the content (chunk structure) of the multimedia data mdat is determined, the metadata moov is usually arranged after the multimedia data mdat in the MP4 file.

  However, when making this MP4 file compatible with streaming playback, moov needs to be placed in front of mdat. This is because, as described above, multimedia data is stored in mdat in units of chunks, and metadata indicating the position of the chunk in mdat (file) is stored in moov.

  In order to create the metadata moov, the configuration of the chunks in the multimedia data mdat must be determined, and the metadata moov needs to be arranged ahead of the multimedia data mdat.

  In addition, the video processing application 202 reads the input media data 31 and 32 in predetermined processing units (a cluster of track data), and generates a chunk in which the read data is multiplexed. Then, the video processing application 202 sequentially generates metadata moov corresponding to the generated chunk. That is, the metadata moov corresponding to the multimedia data mdat is created for each chunk. For this reason, processing has been completed until generation of the metadata moov corresponding to the multimedia data mdat is completed, that is, until generation of metadata corresponding to all chunks in the multimedia data mdat is completed. Chunks (chunks for which corresponding metadata is generated) are buffered in the HDD 111 or the like. However, there is a risk that the buffered multimedia data mdat is read from the buffer and copied. Therefore, the video processing application 202 encrypts the buffered chunk (multimedia data mdat) and protects the multimedia data mdat from unauthorized processing such as copying.

  As shown in FIG. 3, the video processing application 202 includes a multiplexing processing unit 35, a local encryption unit 36, a local decryption unit 37, and an encryption output unit 39. The multiplexing processing unit 35 includes a metadata generation unit 38. The encryption output unit 39 includes a media encryption unit 40 and a data storage unit 41.

  The multiplexing processing unit 35 reads and multiplexes data (a set of track data) of a predetermined processing unit from each of a plurality of input media data (elementary streams) 31 and 32, and generates a multiplexed chunk. To do. The multiplexed chunk is data of a predetermined processing unit constituting the multimedia data mdat stored in the MP4 file. That is, the multiplexing processing unit 35 generates multimedia data mdat obtained by multiplexing a plurality of media data 31 and 32 in units of chunks.

  The media data 31 and 32 are elementary streams such as encoded video data and audio data. The video data is, for example, video data compliant with MPEG-4 Visual (ISO / IEC 14496-2) and H.264 / AVC (H.264 | ISO / IEC 14496-10). The audio data is audio data compliant with, for example, MPEG-4 AAC (ISO / IEC14496-3). Further, the media data 31 and 32 may be not only the elementary stream generated from the accumulated file but also an elementary stream generated by a transcoder that performs stream processing.

  The multiplexing processing unit 35 sequentially outputs the generated chunk (multimedia data mdat) to the local encryption unit 36.

  The metadata generation unit 38 generates metadata moov corresponding to the generated chunk. The metadata moov corresponding to the generated chunk indicates the position and size of the chunk in the multimedia data mdat. The metadata generation unit 38 generates metadata moov corresponding to each chunk.

  The local encryption unit 36 encrypts the generated chunk using the local key. The local encryption unit 36 outputs the encrypted chunk to the encryption buffer 33. The encryption buffer 33 for storing the encrypted chunk is provided in the HDD 111, for example.

  The local decoding unit 37 responds to the completion of the multiplexing of the media data 31 and 32 by the multiplexing processing unit 35 and the generation of the metadata moov corresponding to the multimedia data mdat by the metadata generating unit 38. Thus, the encrypted chunk is read from the encryption buffer 33. Then, the local decryption unit 37 decrypts the encrypted chunk and sequentially outputs the decrypted chunk to the multiplexing processing unit 35. That is, the local decryption unit 37 decrypts the encrypted chunk stored in the encryption buffer 33 in response to the generation of the metadata moov corresponding to all the chunks in the multimedia data mdat. .

  The multiplexing processing unit 35 responds that the multiplexing of the media data 31 and 32 by the multiplexing processing unit 35 is completed and the generation of the metadata moov corresponding to the multimedia data mdat by the metadata generation unit 38 is completed. Then, the metadata moov generated by the metadata generation unit 38 is output to the encryption output unit 39. Also, the multiplexing processing unit 35 outputs the chunk (multimedia data mdat) decrypted by the local decryption unit 37 to the encryption output unit 39.

  The media encryption unit 40 creates a title key using the media key 34A stored in the output medium 34, and encrypts the decrypted chunk using the title key. That is, the media encryption unit 40 generates multimedia data mdat encrypted using the title key in units of chunks. The media encryption unit 40 outputs the multimedia data mdat encrypted using the title key to the data storage unit 41. The media key 34A may be an ID unique to the output medium 34 or the like.

  The data storage unit 41 stores an MP4 file including the metadata moov generated by the metadata generation unit 38 and the multimedia data mdat encrypted by the media encryption unit 40 in the output medium 34. The stored MP4 file supports streaming playback, and the metadata moov is arranged before the multimedia data mdat. In addition, the data storage unit 41 stores the title key created using the media key 34 </ b> A in the output medium 34. The output medium 34 is an SD card inserted into the SD card slot 110, for example.

  With the above configuration, when creating an MP4 file corresponding to streaming reproduction in which the metadata moov is arranged before the multimedia data mdat, the buffered multimedia data mdat is encrypted and stored in the encryption buffer 33. By storing, the multimedia data mdat can be protected and an MP4 file can be created safely. That is, in the process of generating multimedia data mdat obtained by multiplexing a plurality of media data 31 and 32 and creating an MP4 file in which the multimedia data mdat is stored, the MP4 file can be streamed and encrypted. Can be realized simultaneously.

  The key used for encryption by the local encryption unit 36 and decryption by the local decryption unit 37 may be a media key 34A stored in the output medium 34. In this case, the encrypted multimedia data mdat (data stored in the encryption buffer 33) is bound to the output medium 34, and is encrypted using a local key in the information processing apparatus 10. Protected more safely.

  In addition, a title key created by using the media key 34A stored in the output medium 34 may be used for encryption by the local encryption unit 36. In this case, the decryption by the local decryption unit 37 and the encryption by the media encryption unit 40 become unnecessary, and the multimedia data mdat encrypted by using the title key by the local encryption unit 36 is transferred to the encryption output unit 39. And can be directly stored in the output medium 34. Therefore, the processing related to the decryption by the local decryption unit 37 and the encryption by the media encryption unit 40 becomes unnecessary, and the processing amount can be reduced.

  Further, in the above description, the example in which the encryption buffer 33 is provided in the HDD 111 has been described. However, the encryption buffer 33 may be provided in a free area in the output medium 34.

  FIG. 5 is a flowchart showing a procedure of video content data storage processing executed by the information processing apparatus 10.

  First, the video processing application 202 inputs a plurality of media data (elementary streams) 31 and 32 (step S101).

  Next, the video processing application 202 reads and multiplexes data (a set of track data) of a predetermined processing unit from each of a plurality of input media data (elementary streams) 31 and 32, and multiplexes the multiplexed chunks. Is generated (step S102). The multiplexed chunk is data of a predetermined processing unit constituting the multimedia data mdat stored in the MP4 file. That is, the video processing application 202 generates multimedia data mdat obtained by multiplexing a plurality of media data 31 and 32 in units of chunks. Also in the subsequent processing, each processing is performed in units of chunks.

  Next, the video processing application 202 generates metadata moov corresponding to the generated chunk (step S103). As the metadata moov corresponding to the generated chunk, the video processing application 202 describes, for example, an address (offset) indicating the position of the chunk in the multimedia data mdat in stco.

  The video processing application 202 encrypts the generated chunk using the local key (step S104). The video processing application 202 stores the encrypted chunk in the encryption buffer 33 (step S105).

  Then, the video processing application 202 determines whether the stored chunk is the last chunk generated by multiplexing the plurality of input media data 31 and 32 (step S106). That is, the video processing application 202 reads out data of a predetermined processing unit from each of the plurality of input media data 31 and 32 and generates multiplexed multimedia data mdat, and corresponds to the multimedia data mdat. It is determined whether or not the process for generating the metadata moov has been completed.

  When the stored chunk is not the last chunk (NO in step S106), the video processing application 202 performs the processing after step S102. That is, the video processing application 202 generates the next chunk and performs a predetermined process on this chunk.

  When the stored chunk is the last chunk (YES in step S106), the video processing application 202 stores the generated metadata moov in the output medium 34 (step S107).

  Next, the video processing application 202 reads and decrypts the chunk stored in the encryption buffer 33 (step S108). The video processing application 202 generates a title key using the media key 34A stored in the output medium 34, and encrypts the decrypted chunk using the title key (step S109). That is, the video processing application 202 generates multimedia data mdat encrypted with the title key in units of chunks. The video processing application 202 stores the chunk encrypted with the title key in the output medium 34 (step S110).

  Then, the video processing application 202 determines whether or not the chunk stored in the output medium 34 is the last chunk stored in the encryption buffer 33 (step S111). That is, the video processing application 202 determines whether all chunks included in the multimedia data mdat are encrypted with the title key and stored in the output medium 34.

  When the chunk stored in the output medium 34 is not the last chunk (NO in step S111), the video processing application 202 performs the processes in and after step S108. That is, the video processing application 202 reads the next chunk from the encryption buffer 33 and performs a predetermined process on this chunk.

  When the chunk stored in the output medium 34 is the last chunk (YES in step S111), the video processing application 202 ends the process.

  Through the above processing, in order to support streaming playback, when creating an MP4 file in which the metadata moov is arranged before the multimedia data mdat, the buffered multimedia data mdat is encrypted to be an encrypted buffer. By storing in 33, the multimedia data mdat can be protected and an MP4 file can be created safely.

  As described above, according to the present embodiment, a file in which metadata and media data are sequentially arranged can be created safely.

  The information processing apparatus 10 according to the present embodiment creates an MP4 file in which the metadata moov is arranged before the multimedia data mdat in order to support streaming playback. At this time, the multimedia data mdat to be buffered is encrypted and stored in the encryption buffer 33, so that the multimedia data mdat can be protected and an MP4 file can be created safely. In addition, the number of copies (move / dubbing 10 or the like) can be easily controlled using the above-described processing.

  Further, by encrypting the multimedia data mdat using the media key 34A stored in the output medium 34 in the local encryption unit 36, the security for protecting the multimedia data mdat can be further enhanced. . Further, the local encryption unit 36 encrypts the multimedia data mdat using the title key created from the media key 34A, and stores the encrypted data directly in the external storage medium, thereby reducing the processing amount. it can. That is, it is possible to reduce the time required for the process of storing the MP4 file including the multimedia data mdat obtained by multiplexing and encrypting a plurality of elementary streams and corresponding to streaming reproduction in the external storage medium.

  Note that all the procedures of the video content data storage processing of the present embodiment can be executed by software. For this reason, the same effect as that of the present embodiment can be easily realized simply by installing and executing a program for executing the video content data storage processing procedure on a normal computer through a computer-readable storage medium.

  Further, the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope 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. Furthermore, constituent elements over different embodiments may be appropriately combined.

  202 ... Video processing application, 31 ... Input media 1, 32 ... Input media n, 33 ... Encryption buffer, 34 ... Output media, 34A ... Media key, 35 ... Multiplexing processing unit, 36 ... Local encryption unit, 37 ... Local decryption unit, 38 ... metadata generation unit, 39 ... encryption output unit, 40 ... media encryption unit, 41 ... data storage unit.

Claims (6)

Multiplexing means for generating multiplexed media data obtained by multiplexing a plurality of media data for each data of a predetermined processing unit;
Metadata generation means for generating metadata corresponding to the multiplexed media data for each data of the predetermined processing unit;
Local encryption means for generating first encrypted media data obtained by encrypting data of the predetermined processing unit using first key data;
Buffering means for storing the first encrypted media data in a storage device;
In response to the generation of all the metadata corresponding to the multiplexed media data, decryption means for reading the first encrypted media data from the storage device and decrypting the first encrypted media data;
Media encryption means for generating second encrypted media data obtained by encrypting the decrypted first encrypted metadata using second key data;
An information processing apparatus comprising: data storage means for storing the metadata and the second encrypted media data in an external storage medium. The first key data is a local key stored in the information processing apparatus;
The information processing apparatus according to claim 1, wherein the second key data is a title key created using a media key stored in the external storage medium. The first key data is a media key stored in the external storage medium;
The information processing apparatus according to claim 1, wherein the second key data is a title key created using a media key stored in the external storage medium. The first key data is a title key created using a media key stored in the external storage medium,
The data storage means reads the first encrypted media data from the storage device in response to the generation of all the metadata corresponding to the multiplexed media data, and the metadata and the read first The information processing apparatus according to claim 1, wherein encrypted media data is stored in the external storage medium.   The information processing apparatus according to claim 1, wherein the buffering unit stores the first encrypted media data in the external storage medium. A multiplexing step for generating multiplexed media data obtained by multiplexing a plurality of media data for each data in a predetermined processing unit;
A metadata generation step of generating metadata corresponding to the multiplexed media data for each data of the predetermined processing unit;
A local encryption step of generating first encrypted media data obtained by encrypting the data of the predetermined processing unit using first key data;
A buffering step of storing the first encrypted media data in a storage device;
A decrypting step of reading the first encrypted media data from the storage device and decrypting the first encrypted media data in response to all the metadata corresponding to the multiplexed media data being generated;
A media encryption step for generating second encrypted media data obtained by encrypting the decrypted first encrypted metadata using second key data;
A video processing method comprising: a data storage step of storing the metadata and the second encrypted media data in an external storage medium.

Images