Transmitting apparatus, receiving apparatus, and data transmission system
Video data exploitation by alteration of data is prevented. An extractor 111 extracts valid video data in data 110 and predetermined data in the data. An inserter 114 inserts an arithmetic operation result of the predetermined data by an arithmetic operation unit 113 into the valid video data encrypted by an encryptor 112 . An output of the inserter 114 is supplied to an extractor 144 through a transmission path 120 . The encrypted valid video data and arithmetic operation resultant data of the arithmetic operation unit 113 are extracted. An arithmetic operation unit 143 executes the same arithmetic operation as that of the arithmetic operation unit 113 to data corresponding to the data used in the arithmetic operation unit 113 from the valid video data decrypted by a decryptor 141 and extracted by an extractor 144 . A comparator 145 compares an output of the arithmetic operation unit 143 with an arithmetic operation result extracted from data 140 . When both of them do not coincide, it is determined that there is a possibility that the transmission data has been altered. An output of an another-output generator 146 is outputted as output data 148.
1. A transmitting apparatus comprising:
a data extracting device configured to extract predetermined data from input data, the data extracting device also configured to extract apart or all of the input data;
a first encrypting device configured to encrypt the part or all of the input data in accordance with a predetermined rule and outputting encrypted data;
an arithmetic operating device configured to execute a predetermined arithmetic operation to said predetermined data extracted by said data extracting device and outputting arithmetic operation resultant data;
a second encrypting device configured to encrypt the arithmetic operation resultant data and output encrypted arithmetic operation resultant data; and
a data inserting device configured to insert said encrypted arithmetic operation resultant data as metadata at a predetermined position of the encrypted data and transmitting the resultant data to a transmission path.
2. A transmitting apparatus according to claim 1 , wherein said data is video data.
3. A transmitting apparatus according to claim 2 , wherein said data extracting device is configured to extract pixel data at one or a plurality of predetermined positions as said predetermined data.
4. A transmitting apparatus according to claim 2 , wherein said data inserting device is configured to insert the data in a format according to regulations of an HD-SDI.
5. A transmitting apparatus according to claim 4 , wherein said data inserting device is configured to insert said arithmetic operation resultant data into an auxiliary data area according to said HD-SDI format.
6. A transmitting apparatus according to claim 1 , wherein said data extracting device is configured to extract said predetermined data from the data to be encrypted by said encrypting device in said data.
7. A transmitting method comprising:
extracting predetermined data from input data;
extracting a part or all of the input data;
encrypting by a first encryptor device the part or all of the input data in accordance with a predetermined rule and outputting encrypted data;
executing a predetermined arithmetic operation by an arithmetic operation unit to said predetermined data extracted in said data extracting step and outputting arithmetic operation resultant data;
encrypting by a second encryptor device the arithmetic operation resultant data into encrypted arithmetic resultant data; and
inserting said encrypted arithmetic operation resultant data by a data inserter as metadata at a predetermined position of the encrypted data and transmitting the resultant data to a transmission path.
8. A transmitting apparatus comprising:
a data extracting device configured to extract predetermined data from input data on the basis of random numbers generated in accordance with a predetermined rule in accordance with random number control information, the data extracting device also configured to extract a part or all of the input data;
a first encrypting device configured to encrypt the part or all of the input data by using a first key and outputting encrypted data;
an arithmetic operating device configured to execute a predetermined arithmetic operation to said predetermined data extracted by said data extracting means and outputting arithmetic operation resultant data;
a second encrypting device configured to encrypt said arithmetic operation resultant data by using a second key and outputting encrypted arithmetic operation resultant data; and
a data inserting device configured to insert the encrypted arithmetic operation resultant data as metadata at a predetermined position of the encrypted data and transmitting the resultant data to a transmission path.
9. A transmitting apparatus according to claim 8 , wherein said data is video data.
10. A transmitting apparatus according to claim 9 , wherein said data extracting is configured to extract pixel data at one or a plurality of predetermined positions as said predetermined data.
11. A transmitting apparatus according to claim 9 , wherein said data inserting device is configured to transmit the data in a format according to regulations of an HD-SDI.
12. A transmitting apparatus according to claim 11 , wherein said data inserting device is configured to insert said arithmetic operation resultant data into an auxiliary data area according to said HD-SDI format.
13. A transmitting apparatus according to claim 8 , wherein said data extracting device is configured to extract said predetermined data from the data to be encrypted by said first encrypting device in said data.
14. A transmitting apparatus according to claim 8 , wherein said first and second keys have a same value.
15. A transmitting apparatus according to claim 8 , wherein said random number control information and said first and second keys have a same value.
16. A transmitting method comprising:
extracting predetermined data from input data on the basis of random numbers generated in accordance with a predetermined rule in accordance with random number control information;
extracting a part or all of the input data;
encrypting by first encryptor device a part or all of input data by using a first key and outputting the encrypted data;
encrypting by a first encryptor device the part or all of the input data in accordance with a predetermined rule and outputting encrypted data;
executing a predetermined arithmetic operation by an arithmetic operation unit to said predetermined data and outputting arithmetic operation resultant data;
encrypting by a second encryptor device said arithmetic operation resultant data in accordance with a predetermined rule by using a second key and outputting encrypted arithmetic operation resultant data; and
inserting said encrypted arithmetic operation resultant data by a data inserter as metadata at a predetermined position of the encrypted data and transmitting the resultant data to a transmission path.