VIDEO STREAM TRUST RATING

Claims

1. A device (16) for checking a video data stream (14) in which the video is encoded for the degree of trust, wherein the device is configured to: applying a hash function (31) to a predetermined portion (13) of the video data stream or data extracted therefrom to obtain a hash value (33); extracting a digital signature (43) from a video data stream; and checking (41) whether the hash value (33) matches the digital signature (43) to determine whether the video data stream is trusted, In this case, the video is encoded into a video data stream using: encoding video into a video data stream using block-based predictive coding and transform-based residual coding by: encoding the residual data of the prediction residual block into a video data stream: by using context-adaptive binary arithmetic coding through: encoding a significance map that indicates the positions of non-zero transform coefficients in a transform block representing the residual block by, while traversing, in a forward scan, the transform coefficients of the transform block, encoding a significance flag that indicates whether a non-zero transform coefficient is located at the current position, and if so, and if the current position is not the last one in the forward scan, encoding a last significance flag that indicates whether the non-zero transform coefficient located at the current position is the last non-zero transform coefficient in the forward scan order, and encoding the values ​​of non-zero transform coefficients sequentially in reverse scanning order, reversing the direct scanning order.

2. The device according to paragraph 1, wherein the digital signature is transmitted in a message with additional enhancing information of the video data stream.

3. The device according to claim 1 or 2, configured to, when checking (41) whether the hash value of the digital signature matches, in order to determine whether the video data stream is trusted: decrypting (45) the digital signature to obtain a verification value (47); and checking (49) whether the hash value (33) matches the check value (47).

4. A device according to any one of paragraphs 1-3, configured to, when applying a hash function to a predetermined portion (22) of the video data stream or data extracted therefrom, obtain a hash value: restoring the video relative to a predetermined portion to obtain the restored portion of the video, and applying a hash function to the recovered part.

5. A device according to any one of paragraphs 1-4, wherein the device is a decoder (20) configured to: decoding video from a video data stream, and decoding a digital signature from a video data stream.

6. The device according to claim 5, configured to decode a digital signature from a message with additional enhancing information of a video data stream.

7. The device according to claim 5 or 6, configured to determine the location of a predetermined portion in a video data stream by using one or more SEI messages (21, 25, 27) embedded in the video data stream and defining the predetermined portion as a section of the video data stream extending between or extending from the one or more SEI messages.

8. The device of claim 7, configured to decode a digital signature from one of one or more SEI messages of a video data stream.

9. The device according to claim 5 or 6, configured to determine the location of a predetermined portion (13) in a video data stream by using a prefix SEI message (25) and a suffix SEI message (25) embedded in the video data stream, and defining the predetermined portion as a section of the video data stream extending between or located between the prefix and suffix SEI messages.

10. The device according to claim 5 or 6, configured to determine the location of a predetermined portion (13) in a video data stream by using a prefix SEI message (25) and a suffix SEI message (25) embedded in the video data stream, and determining the predetermined portion as being located between the prefix and suffix SEI messages.

11. The device according to claim 9 or 10, configured to decode a digital signature from a suffix SEI message.

12. The device according to claim 5 or 6, configured to determine the location of a predetermined portion (13) in a video data stream by using a first SEI message (25) and a second SEI message (27) embedded in the video data stream and determining the predetermined portion as a section of the video data stream extending between or located between the first and second SEI messages, or as a section of the video data stream extending between the first SEI message and a point in the data stream that is located downstream of the second SEI message.

13. The device according to claim 5 or 6, configured to determine the location of a predetermined portion (13) in a video data stream by using a first SEI message (25) and a second SEI message (27) embedded in the video data stream and determining the predetermined portion as being located between the first and second SEI messages or located between the first SEI message and a point in the data stream that is located downstream of the second SEI message.

14. The device according to claim 12 or 13, configured to determine a point in the data stream that is located downstream of the second SEI message, based on the length of the section, or as being located at the end of the portion of the video coding layer with the access unit of the video data stream, into which the second SEI message falls.

15. A device according to any one of paragraphs 12-14, configured to decode a digital signature from a second SEI message.

16. The device according to paragraph 5 or 6, configured to: extracting an SEI overview message from a video data stream, wherein the SEI overview message specifies one or more substreams of the video data stream, with respect to each of which verification of the video data stream for a degree of trust is possible based on one or more parts in the corresponding substream; and performing a check of a video data stream for a degree of trust in relation to a subset of one or more substreams of said one or more substreams by means of, for a predetermined substream of this subset: determining the location of a portion of a predetermined substream of a video data stream by using one or more first SEI messages and a second SEI message embedded in the video data stream, and determining the portion of the predetermined substream as a section of the video data stream formed by concatenating subsections of the video data stream following each of the one or more first SEI messages and extending up to the end of the video coding layer of the access unit in which the corresponding first SEI message is contained, and a subsection preceding the second SEI message and extending up to the beginning of the video coding layer of the access unit in which the second SEI message is contained, or following the second SEI message and extending up to the end of the video coding layer of the access unit in which the second SEI message is contained.

17. The device according to paragraph 5 or 6, configured to: extracting an SEI overview message from a video data stream, wherein the SEI overview message specifies one or more substreams of the video data stream, with respect to each of which verification of the video data stream for a degree of trust is possible based on one or more parts in the corresponding substream; and performing a check of a video data stream for a degree of trust in relation to a subset of one or more substreams of said one or more substreams by means of, for a predetermined substream of this subset: determining the location of a portion of a predetermined substream of a video data stream by using one or more first SEI messages embedded in the video data stream, and determining the portion of the predetermined substream as a section of the video data stream formed by concatenating subsections of the video data stream following each of the one or more first SEI messages and extending up to the end of the video coding layer of the access unit in which the corresponding first SEI message is contained.

18. The device according to paragraph 5 or 6, configured to: extracting an SEI overview message from a video data stream, wherein the SEI overview message specifies one or more substreams of the video data stream, with respect to each of which verification of the video data stream for a degree of trust is possible based on one or more parts in the corresponding substream; and performing a check of a video data stream for a degree of trust in relation to a subset of one or more substreams of said one or more substreams by determining the corresponding portions of the video data stream for the one or more substreams by: checking, for a picture unit of a video data stream, whether the video data stream includes a substream selection SEI message for the picture unit, and assigning payload packets of the encoded video layer of the image unit to a first substream of one or more substreams if the video data stream does not include a substream selection SEI message for the image unit, and if the video data stream includes a sub-stream selection SEI message for a picture unit, assigning payload packets of the encoded video layer of the picture unit to a sub-stream of one or more sub-streams, which sub-stream is indicated by the sub-stream selection SEI message.

19. The device according to any one of paragraphs 16-18, configured to check the video data stream for a degree of trust in relation to a subset of one or more substreams further by applying a hash function to portions determined for one or more substreams from the subset of one or more substreams in order to obtain corresponding hash values.

20. The apparatus of any one of claims 16-19, further configured to determine corresponding portions for substreams from the subset of one or more substreams by using a first SEI message (25) and a second SEI message (27) embedded in the video data stream, and determining the portions as being located between the first and second SEI messages or located between the first SEI message and a point in the data stream that is located downstream of the second SEI message.

21. The apparatus of any one of claims 16-20, further configured to determine corresponding portions for substreams from the subset of one or more substreams as terminating at or before the end of the encoded video sequence.

22. The device according to any one of paragraphs 17-21, wherein the one or more sub-streams have an order defined between them, and the device is configured to determine a predetermined portion as a portion of a predetermined sub-stream from a subset of the one or more sub-streams, and is configured to: performing a trust check of the video data stream sequentially with respect to the corresponding parts of the video data stream extracted for one or more substreams by: checks that: whether the hash value and the additional hash value obtained by applying the hash function to the preceding portion of the predetermined portion or additional data extracted therefrom correspond to the digital signature, or whether the combined hash value obtained by hashing the predetermined portion and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted from it corresponds to the digital signature, where the previous part precedes the previously determined part in the sequential order specified between the parts.

23. A device according to any one of paragraphs 1-21, configured to: performing a verification of the video data stream for the degree of trust sequentially with respect to a plurality of parts of the video data stream, and additionally by: checks that: whether the hash value and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted from it correspond to the digital signature, or whether the combined hash value obtained by hashing the predetermined portion and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom corresponds to the digital signature.

24. The device according to item 22 or 23, configured to be subjected to: the hash value and the additional hash value are combined to produce a combined hash value, and the combined hash value is verified to match the digital signature, or a predetermined portion and an additional hash value obtained by applying a hash function to the previous portion of the video data stream or additional data extracted therefrom, combining to obtain a combined hash value, and checking whether the combined hash value matches the digital signature.

25. The device of claim 24, wherein said combination is a concatenation.

26. The device according to paragraphs 22, 23, 24 or 25, configured to further check whether the parameter or identifier corresponds to the hash function of the digital signature in order to determine whether the video data stream is trusted.

27. The device according to any one of paragraphs 1-26, wherein two different digital signatures are transmitted in the video data stream for a predetermined portion, and the device is configured to: performing a trust check of a video data stream sequentially with respect to a plurality of parts of the video data stream, and by: if the video data stream contains a previous part relative to a predefined part: checks that: whether the hash value and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted from it correspond to the first of two different digital signatures, or whether the combined hash value obtained by hashing the predetermined portion and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom, matches the first of two different digital signatures, and if the video data stream does not contain a previous part relative to the predefined part: checking whether the hash value of the second of two different digital signatures matches to determine whether the video data stream is trusted.

28. A device according to any one of paragraphs 1-26, wherein the device is configured to: performing a trust check of a video data stream sequentially with respect to a plurality of parts of the video data stream, and by: if the video data stream contains a previous part relative to a predefined part: checks that: whether the hash value and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom correspond to the digital signature, or whether the hash value and the additional hash value transmitted in the video data stream for a predetermined portion correspond to the digital signature, wherein the additional hash value mentioned is equal to the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom, and whether the combined hash value obtained by hashing the predetermined portion, on the one hand, and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom, on the other hand, corresponds to the first of two different digital signatures, or whether the combined hash value obtained by hashing the hash value and an additional hash value transmitted in the video data stream for the predetermined portion corresponds to the digital signature, wherein the said additional hash value is equal to the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom, and if the video data stream does not contain a previous part relative to the predefined part: checking whether the hash value matches the digital signature to determine whether the video data stream is trusted.

29. The device according to paragraph 28, wherein the device is configured to: if the video data stream does not contain a previous part relative to the predefined part: checking whether the hash value matches the digital signature to determine whether the video data stream is trusted by checking whether the hash value and an additional hash value carried in the video data stream for a predetermined portion match the digital signature.

30. A device according to any one of paragraphs 1-29, in which the compliance of the digital signature with a predetermined value is ensured in the event of: equality of the predetermined value with a check value obtained by decrypting the digital signature or a predetermined portion of the check value associated with the predetermined value, or equality with a check value in an additional hashed region, achieved by means of an additional hash function applied to a predefined value or to a concatenation of a value that includes the predefined value.

31. A device according to any one of paragraphs 1-30, configured to perform verification by using an asymmetric decryption scheme using a public key.

32. The device of claim 31, configured to obtain an asymmetric decryption scheme using first information extracted from the data stream.

33. The device of claim 32, wherein the first information comprises an indicator of a decryption scheme or a first pointer to a first location from which an asymmetric decryption scheme can be determined, or an identifier of the entity that encoded the video into the video data stream.

34. The device according to any one of paragraphs 31-33, configured to obtain a public key using second information extracted from the data stream.

35. The apparatus of claim 34, wherein the second information comprises a second pointer to a second location from which a public key or an identifier of the subject who encoded the video into the video data stream can be retrieved.

36. The device according to any one of paragraphs 31-35, configured to obtain a public key by extracting a first syntax element and a second syntax element from a video data stream, wherein the second syntax element indicates a pointer to a location from which the public key can be extracted, and the device is configured to: if the first syntax element has the first state, infer that the location identifies exactly one public key, and extract exactly one public key from the location; and if the first syntax element has a second state, infer that the location specifies a list of keys, extract a third syntax element from the video data stream, wherein the third syntax element specifies a pointer to an entry in the list of keys, and extract a public key from the entry in the list of keys specified by the pointer.

37. A device according to any one of paragraphs 1-36, configured to obtain a hash function using third information extracted from the data stream.

38. The device of claim 37, wherein the third information comprises a hash function indicator or a third pointer to a third location from which the hash function can be determined, or an identifier of the entity that encoded the video into the video data stream.

39. The device according to any one of paragraphs 1-38, wherein the hash value depends on each bit of a predetermined portion of the video data stream.

40. The apparatus of any one of paragraphs 1-39, wherein the hash value depends on each bit of a predetermined portion of the video data stream in the entropy encoded region.

41. The apparatus of any one of claims 1-40, wherein the predetermined portion of the video data stream is extended over more than one access unit of the video data stream, such that the hash value depends on bits of more than one access unit.

42. The device according to any one of paragraphs 1-41, configured to check the video data stream for a degree of trust additionally by checking that the hash function is correct by checking whether the parameterization or identifier of the hash function corresponds to the digital signature.

43. The device according to any one of claims 1-42, wherein the predetermined portion consists of one or more portions of a video coding layer of a video data stream, into which motion vectors and intra-prediction modes for prediction blocks and transform coefficients for residual blocks are encoded.

44. A device according to any of the preceding claims, adapted to provide a hash value for subjecting, along with an additional hash value obtained by applying a hash function or another hash function to a portion of a media stream accompanying a video data stream, or additional data extracted therefrom, to a verification of the degree of trust of the video data stream combined with the media stream.

45. A decoder (20) for decoding video from a video data stream (14), wherein the decoder is configured to: decoding (63) a digital signature (43) from a video data stream; subjecting the digital signature of the video data stream to verification of its trust level by means of: applying a hash function (31) to a predetermined portion (13) of the video data stream or data (62) extracted therefrom to obtain a hash value (33), and checking (41) whether the hash value matches the digital signature to determine whether the video data stream is trusted, wherein the decoder is configured to decode video from a video data stream by means of block-based predictive decoding and transform-based residual decoding by means of: decoding the residual data of the prediction residual block from the video data stream: by using context-adaptive binary arithmetic decoding through decoding a significance map that indicates the positions of non-zero transform coefficients in a transform block representing the residual block by, while traversing, with a forward scan, the transform coefficients of the transform block, decoding a significance flag that indicates whether a non-zero transform coefficient is located at the current position, and if so, and if the current position is not the last one in the forward scan, decoding a last significance flag that indicates whether the non-zero transform coefficient located at the current position is the last non-zero transform coefficient in the forward scan order, and decoding the values ​​of non-zero transformation coefficients sequentially in reverse scanning order, changing the direct scanning order to the opposite.

46. ​​The decoder according to claim 45, wherein the digital signature is transmitted in a message with additional enhancing information of the video data stream.

47. The decoder according to claim 45 or 46, wherein checking the video data stream for a degree of trust includes: decrypting the digital signature to obtain the verification value; and checking whether the hash value matches the check value.

48. A decoder according to any one of paragraphs 45-47, in which applying a hash function to a predetermined portion of the video data stream or data extracted therefrom to obtain a hash value includes: restoring the video relative to a predetermined portion to obtain a restored portion of the video, and applying a hash function to the recovered portion.

49. A decoder according to any one of paragraphs 45-48, configured to decode a digital signature from a message with additional enhancing information of a video data stream.

50. The decoder of any one of paragraphs 45-49, wherein checking the video data stream for a degree of trust includes determining the location of a predetermined portion in the video data stream by using one or more SEI messages embedded in the video data stream, and determining the predetermined portion as a section of the video data stream extending between or extending from the one or more SEI messages.

51. The decoder of claim 50, configured to decode a digital signature from one of one or more SEI messages of a video data stream.

52. The decoder of any one of paragraphs 45-49, wherein checking the video data stream for a degree of trust includes determining the location of a predetermined portion in the video data stream by using a prefix SEI message and a suffix SEI message embedded in the video data stream, and determining the predetermined portion as a section of the video data stream extending between or located between the prefix and suffix SEI messages.

53. A decoder according to any one of claims 45-49, wherein checking the video data stream for a degree of trust includes determining the location of a predetermined portion (13) in the video data stream by using a prefix SEI message (25) and a suffix SEI message (25) embedded in the video data stream, and determining the predetermined portion as being located between the prefix and suffix SEI messages.

54. A decoder according to claim 52 or 53, configured to decode a digital signature from a suffix SEI message.

55. The decoder of claim 51 or 52, configured to determine the location of a predetermined portion in a video data stream by using a first SEI message and a second SEI message embedded in the video data stream and determining the predetermined portion as a section of the video data stream extending between or located between the first and second SEI messages, or as a section of the video data stream extending between the first SEI message and a point in the data stream that is located downstream of the second SEI message.

56. The decoder according to claim 51 or 52, configured to determine the location of a predetermined portion (13) in a video data stream by using a first SEI message (25) and a second SEI message (27) embedded in the video data stream, and determining the predetermined portion as being located between the first and second SEI messages or located between the first SEI message and a point in the data stream that is located downstream of the second SEI message.

57. The decoder according to claim 55 or 56, wherein the point in the data stream that is located downstream of the second SEI message is determined based on the length of the section, or as being located at the end of the portion of the video coding layer with the access unit of the video data stream into which the second SEI message falls.

58. A decoder according to any one of paragraphs 55-57, configured to decode a digital signature from a second SEI message.

59. A decoder according to any one of paragraphs 45-52, configured to: extracting an SEI overview message from a video data stream, wherein the SEI overview message specifies one or more substreams of the video data stream, with respect to each of which verification of the video data stream for a degree of trust is possible based on one or more parts in the corresponding substream; and wherein checking the video data stream for a degree of trust includes performing a check of the video data stream for a degree of trust with respect to a subset of one or more substreams from said one or more substreams by means of, for a predetermined substream from this subset: determining the location of one or more portions in a predetermined substream of a video data stream by using one or more first SEI messages and a second SEI message embedded in the video data stream, and determining the predetermined portion as a section of the video data stream formed by concatenating subsections of the video data stream following each of the one or more first SEI messages and extending up to the end of the video coding layer of the access unit in which the corresponding first SEI message is contained, and a subsection preceding the second SEI message and extending up to the beginning of the video coding layer of the access unit in which the second SEI message is contained, or following the second SEI message and extending up to the end of the video coding layer of the access unit in which the second SEI message is contained.

60. A decoder according to any one of paragraphs 45-52, configured to: extracting an SEI overview message from a video data stream, wherein the SEI overview message specifies one or more substreams of the video data stream, with respect to each of which verification of the video data stream for a degree of trust is possible based on one or more parts in the corresponding substream; and wherein checking the video data stream for a degree of trust includes performing a check of the video data stream for a degree of trust with respect to a subset of one or more substreams from said one or more substreams by means of, for a predetermined substream from this subset: determining the location of a portion of a predetermined substream of a video data stream by using one or more first SEI messages embedded in the video data stream, and determining the portion of the predetermined substream as a section of the video data stream formed by concatenating subsections of the video data stream following each of the one or more first SEI messages and extending up to the end of the video coding layer of the access unit in which the corresponding first SEI message is contained.

61. A decoder according to any one of paragraphs 45-52, configured to: extracting an SEI overview message from a video data stream, wherein the SEI overview message specifies one or more substreams of the video data stream, with respect to each of which verification of the video data stream for a degree of trust is possible based on one or more parts in the corresponding substream; and wherein checking the video data stream for a degree of trust includes performing a check of the video data stream for a degree of trust with respect to a subset of one or more substreams of said one or more substreams by determining the corresponding portions of the video data stream for the one or more substreams by: checking, for a picture unit of a video data stream, whether the video data stream includes a substream selection SEI message for the picture unit, and assigning payload packets of the encoded video layer of the image unit to a first substream of one or more substreams if the video data stream does not include a substream selection SEI message for the image unit, and if the video data stream includes a sub-stream selection SEI message for a picture unit, assigning payload packets of the encoded video layer of the picture unit to a sub-stream of one or more sub-streams, which sub-stream is indicated by the sub-stream selection SEI message.

62. A decoder according to any one of paragraphs 59-61, in which checking the video data stream for a degree of trust includes performing the checking of the video data stream for a degree of trust with respect to a subset of one or more substreams further by applying a hash function to portions determined for one or more substreams from the subset of one or more substreams to obtain corresponding hash values.

63. The decoder of any one of claims 59-62, further configured to determine corresponding portions for substreams from the subset of one or more substreams by using a first SEI message (25) and a second SEI message (27) embedded in the video data stream, and determining the portions as being located between the first and second SEI messages or located between the first SEI message and a point in the data stream that is located downstream of the second SEI message.

64. The decoder of any one of paragraphs 59-63, further configured to determine corresponding portions for substreams from the subset of one or more substreams as terminating at or before the end of the encoded video sequence.

65. A decoder according to any one of paragraphs 60-63, wherein the one or more substreams have an order defined between them, and the decoder is configured to determine a predetermined portion as a portion of a predetermined substream from a subset of the one or more substreams, and wherein checking the video data stream for a degree of trust includes performing the checking of the video data stream for a degree of trust sequentially with respect to corresponding parts of the video data stream extracted for one or more substreams by: checks that: whether the hash value and the additional hash value obtained by applying the hash function to the preceding portion of the predetermined portion or additional data extracted therefrom correspond to the digital signature, or whether the combined hash value obtained by hashing the predetermined portion and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted from it corresponds to the digital signature, where the previous part precedes the previously determined part in the sequential order specified between the parts.

66. A decoder according to any one of paragraphs 45-64, in which checking the video data stream for a degree of trust includes: performing a trustworthiness check of a video data stream sequentially with respect to a plurality of parts of the video data stream and additionally by: checks that: whether the hash value and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted from it correspond to the digital signature, or whether the combined hash value obtained by hashing the predetermined portion and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom corresponds to the digital signature.

67. The decoder of claim 65 or 66, wherein checking the video data stream for a degree of trust comprises subjecting it to: the hash value and the additional hash value are combined to produce a combined hash value, and the combined hash value is verified to match the digital signature, or a predetermined portion and an additional hash value obtained by applying a hash function to the previous portion of the video data stream or additional data extracted therefrom, combining to obtain a combined hash value, and checking whether the combined hash value matches the digital signature.

68. The decoder of claim 67, wherein said combination is a concatenation.

69. A decoder according to any one of paragraphs 65-68, in which checking the video data stream for a degree of trust includes further checking whether the identifier matches the hash function of the digital signature to determine whether the video data stream is trusted.

70. A decoder according to any one of paragraphs 45-69, wherein two different digital signatures are transmitted in the video data stream for a predetermined portion, and wherein checking the video data stream for a degree of trust comprises: performing a trustworthiness check on a video data stream sequentially with respect to a plurality of parts of the video data stream, and by: if the video data stream contains a previous part relative to a predefined part: checking that: whether the hash value and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted from it correspond to the first of two different digital signatures, or whether the combined hash value obtained by hashing the predetermined portion and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom, matches the first of two different digital signatures, and if the video data stream does not contain a previous part relative to the predefined part: checking whether the hash value of the second of two different digital signatures matches to determine whether the video data stream is trusted.

71. A decoder according to any one of paragraphs 45-69, wherein checking the video data stream for a degree of trust includes: performing a trustworthiness check on a video data stream sequentially with respect to a plurality of parts of the video data stream, and by: if the video data stream contains a previous part relative to a predefined part: checking that: whether the hash value and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom correspond to the digital signature, or whether the hash value and the additional hash value transmitted in the video data stream for a predetermined portion correspond to the digital signature, wherein the additional hash value mentioned is equal to the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom, and whether the combined hash value obtained by hashing the predetermined portion, on the one hand, and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom, on the other hand, corresponds to the first of two different digital signatures, or whether the combined hash value obtained by hashing the hash value and an additional hash value transmitted in the video data stream for the predetermined portion corresponds to the digital signature, wherein the said additional hash value is equal to the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom, and if the video data stream does not contain a previous part relative to the predefined part: checking whether the hash value matches the digital signature to determine whether the video data stream is trusted.

72. The decoder of claim 71, wherein checking the video data stream for a degree of trust includes: if the video data stream does not contain a previous part relative to the predefined part: checking whether the hash value matches the digital signature to determine whether the video data stream is trusted by checking whether the hash value and an additional hash value transmitted in the video data stream for a predetermined portion match the digital signature.

73. A decoder according to any one of paragraphs 45-72, in which the compliance of the digital signature with a predetermined value is ensured in the event of: equality of the predetermined value with a check value obtained by decrypting the digital signature or a predetermined portion of the check value associated with the predetermined value, or equality with a check value in an additional hashed region, achieved by means of an additional hash function applied to a predefined value or to a concatenation of a value that includes the predefined value.

74. A decoder according to any one of paragraphs 45-73, in which checking the video data stream for a degree of trust includes using an asymmetric decryption scheme using a public key.

75. The decoder of claim 74, configured to obtain an asymmetric decryption scheme using the first information extracted from the data stream.

76. The decoder of claim 75, wherein the first information comprises an indicator of a decryption scheme or a first pointer to a first location from which an asymmetric decryption scheme can be determined, or an identifier of the entity that encoded the video into the video data stream.

77. A decoder according to any one of paragraphs 45-76, configured to obtain a public key using second information extracted from the data stream.

78. The decoder of claim 77, wherein the second information comprises a second pointer to a second location from which a public key or an identifier of the entity that encoded the video into the video data stream can be retrieved.

79. A decoder according to any one of paragraphs 74-78, configured to obtain a public key by extracting a first syntax element and a second syntax element from a video data stream, wherein the second syntax element indicates a pointer to a location from which the public key can be extracted, and the decoder is configured to: if the first syntax element has the first state, infer that the location identifies exactly one public key, and extract exactly one public key from the location; and if the first syntax element has the second state, infer that the location specifies a key list and extract a third syntax element from the video data stream, wherein the third syntax element specifies a pointer to an entry in the key list.

80. A decoder according to any one of paragraphs 45-79, configured to obtain a hash function using third information extracted from the data stream.

81. The decoder of claim 80, wherein the third information comprises a hash function indicator or a third pointer to a third location from which the hash function can be determined, or an identifier of the entity that encoded the video into the video data stream.

82. A decoder according to any one of paragraphs 45-81, wherein the hash value depends on each bit of a predetermined portion of the video data stream.

83. A decoder according to any one of paragraphs 45-82, wherein the hash value depends on each bit of a predetermined portion of the video data stream in the entropy coded region.

84. A decoder according to any one of paragraphs 45-83, wherein the predetermined portion of the video data stream is extended over more than one access unit of the video data stream, such that the hash value depends on bits of more than one access unit.

85. A decoder according to any one of paragraphs 45-84, in which checking the video data stream for a degree of trust includes checking that the hash function is correct by checking whether the parameterization or identifier of the hash function matches the digital signature.

86. A decoder according to any one of claims 45-85, wherein the predetermined portion consists of one or more portions of a video coding layer of a video data stream, into which motion vectors and intra-prediction modes for prediction blocks and transform coefficients for residual blocks are encoded.

87. A decoder according to any one of paragraphs 45-86, adapted to provide a hash value for subjecting, along with an additional hash value obtained by applying a hash function or another hash function to a portion of the media stream accompanying the video data stream, or additional data extracted therefrom, to a check of the degree of trust of the video data stream combined with the media stream.

88. A device (15) for generating a stream (14) of video data into which video is encoded, being checked for the degree of trust, wherein the device is configured to: applying a hash function (31) to a predetermined portion (13) of the video data stream or data extracted therefrom to obtain a hash value (33); calculating a digital signature (43) based on the hash value (33) to digitally sign the hash value (33), and inserting (77) a digital signature (43) into a video data stream (14), thereby making it possible to determine whether the video data stream is trusted by checking whether the hash value (33) matches the digital signature (43), In this case, the video is encoded into a video data stream using: encoding video into a video data stream using block-based predictive coding and transform-based residual coding by: encoding the residual data of the prediction residual block into a video data stream: by using context-adaptive binary arithmetic coding through: encoding a significance map that indicates the positions of non-zero transform coefficients in a transform block representing the residual block by, while traversing, in a forward scan, the transform coefficients of the transform block, encoding a significance flag that indicates whether a non-zero transform coefficient is located at the current position, and if so, and if the current position is not the last one in the forward scan, encoding a last significance flag that indicates whether the non-zero transform coefficient located at the current position is the last non-zero transform coefficient in the forward scan order, and encoding the values ​​of non-zero transform coefficients sequentially in reverse scanning order, reversing the direct scanning order.

89. The device according to claim 88, configured to insert a digital signature into a message with additional enhancing information of the video data stream.

90. The device according to item 88 or 89, configured to calculate a digital signature based on a hash value by means of: generating a check value based on the hash value, encryption of the verification value to obtain a digital signature.

91. The device of any one of paragraphs 88-90, wherein applying a hash function to a predetermined portion of the video data stream or data extracted therefrom to obtain a hash value comprises: restoring the video relative to a predetermined portion to obtain a restored portion of the video, and applying a hash function to the recovered portion.

92. The device according to any one of paragraphs 88-91, wherein the device is an encoder configured to: encoding video into a video data stream, and encoding a digital signature into a video data stream.

93. The device according to claim 92, configured to encode a digital signature into a message with additional enhancing information of the video data stream.

94. The apparatus of claim 92 or 93, wherein the location of the predetermined portion is to be determined in the video data stream by using one or more SEI messages embedded in the video data stream and defining the predetermined portion as a section of the video data stream extending between or extending from the one or more SEI messages.

95. The device of claim 94, configured to encode a digital signature into one of one or more SEI messages of a video data stream.

96. The apparatus of claim 92 or 93, wherein the location of the predetermined portion is to be determined in the video data stream by using a prefix SEI message and a suffix SEI message embedded in the video data stream, and defining the predetermined portion as a section of the video data stream extending between or located between the prefix and suffix SEI messages.

97. The apparatus of claim 92 or 93, wherein the location of the predetermined portion is to be determined in the video data stream by using a prefix SEI message (25) and a suffix SEI message (25) embedded in the video data stream, and defining the predetermined portion as being located between the prefix and suffix SEI messages.

98. The device according to item 96 or 97, configured to encode a digital signature into a suffix SEI message.

99. The apparatus of claim 92 or 93, wherein the location of the predetermined portion is to be determined in the video data stream by using a first SEI message and a second SEI message embedded in the video data stream and defining the predetermined portion as a section of the video data stream extending between or located between the first and second SEI messages, or as a section of the video data stream extending between the first SEI message and a point in the data stream that is located downstream of the second SEI message.

100. The apparatus of claim 92 or 93, wherein the location of the predetermined portion is to be determined in the video data stream by using a first SEI message (25) and a second SEI message (27) embedded in the video data stream and defining the predetermined portion as being located between the first and second SEI messages or being located between the first SEI message and a point in the data stream that is located downstream of the second SEI message.

101. The device of claim 100, wherein the point in the data stream that is located downstream of the second SEI message must be determined based on the length of the section, or as being located at the end of the portion of the video coding layer with the access unit of the video data stream into which the second SEI message falls.

102. The device according to claim 100 or 101, configured to encode a digital signature into a second SEI message.

103. The device according to item 92 or 93, configured to inserting a summary SEI message into a video data stream, wherein the summary SEI message specifies one or more substreams of the video data stream, with respect to each of which verification of the video data stream for a degree of trust is possible based on one or more parts in the corresponding substream; and in this case, for a pre-defined substream from the subset: the location of a portion of the predetermined substream must be determined by using one or more first SEI messages and a second SEI message embedded in the video data stream, and by defining the portion of the predetermined substream as a section of the video data stream formed by concatenating subsections of the video data stream following each of the one or more first SEI messages and extending up to the end of the video coding layer of the access unit that contains the corresponding first SEI message, and a subsection preceding the second SEI message and extending up to the beginning of the video coding layer of the access unit that contains the second SEI message, or following the second SEI message and extending up to the end of the video coding layer of the access unit that contains the second SEI message, and inserting a digital signature into the second SEI message.

104. The device according to item 92 or 93, configured to inserting a summary SEI message into a video data stream, wherein the summary SEI message specifies one or more substreams of the video data stream, with respect to each of which verification of the video data stream for a degree of trust is possible based on one or more parts in the corresponding substream; and in this case, for a pre-defined substream from the subset: the location of a portion of the predetermined substream must be determined by using one or more first SEI messages embedded in the video data stream, and by defining the portion of the predetermined substream as a section of the video data stream formed by concatenating subsections of the video data stream following each of the one or more first SEI messages and extending up to the end of the video coding layer of the access unit in which the corresponding first SEI message is contained.

105. The device according to any one of paragraphs 88-104, in which the checking of the video data stream for the degree of trust can be performed sequentially with respect to a plurality of parts of the video data stream and additionally by: digital signing using and calculating a digital signature based on a hash value and an additional hash value obtained by applying a hash function to the previous portion of the video data stream or additional data extracted from it, or digital signing using and calculating a digital signature based on a combined hash value obtained by hashing a predetermined portion and an additional hash value obtained by applying a hash function to the previous portion of the video data stream or additional data extracted from it.

106. The device according to item 105, configured to be subjected to: the hash value and the additional hash value are combined to obtain a combined hash value, and a digital signature is calculated to digitally sign the combined hash value, or a predetermined value and an additional hash value obtained by applying a hash function to the previous portion of the video data stream or additional data extracted therefrom, combining to obtain a combined hash value, and calculating a digital signature for digitally signing the combined hash value.

107. The device of claim 106, wherein said combination is a concatenation.

108. A device according to any one of paragraphs 105-107, configured with the possibility of additional digital signing using and calculating a digital signature based on a hash function identifier.

109. The device according to any one of paragraphs 88-108, configured to insert two different digital signatures in a video data stream for a predetermined portion by calculating the first of them based on a hash value and an additional hash value obtained by applying a hash function to the previous portion of the video data stream or additional data extracted from it, or a combined hash value obtained by hashing the predetermined portion and the additional hash value, for digitally signing the combination of the hash value and the additional hash value and the first of them by calculating the second of them based on the hash value, for digitally signing the hash value, so that the verification of the video data stream for the degree of trust is ensured by: if the video data stream contains a previous part relative to a predefined part: checks that: whether the hash value and the additional hash value match the first of two different digital signatures, or whether the combined hash value obtained by hashing the predetermined portion and the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom, matches the first of two different digital signatures, and if the video data stream does not contain a previous part relative to the predefined part: checking whether the hash value of the second of two different digital signatures matches to determine whether the video data stream is trusted.

110. The device according to any one of paragraphs 88-108, configured to calculate a digital signature based on a hash value and an additional hash value obtained by applying a hash function to a previous portion of the video data stream or additional data extracted therefrom, or a combined hash value obtained by hashing a predetermined portion and the additional hash value, to digitally sign the combination of the hash value and the additional hash value, and insert the digital signature into the video data stream for the predetermined portion along with an additional hash value equal to the additional hash value, So: Verification of the video data stream for the degree of trust is ensured by: if the video data stream contains a previous part relative to a predefined part: checks that: whether the hash value and the additional hash value correspond to the digital signature, or whether the hash value and an additional hash value transmitted in the video data stream for a predetermined portion correspond to the digital signature, wherein said additional hash value is equal to the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom, and whether the combined hash value obtained by hashing the predetermined portion, on the one hand, and the additional hash value, on the other hand, corresponds to the first of two different digital signatures, or whether the combined hash value obtained by hashing the hash value and the additional hash value transmitted in the video data stream for the predetermined portion corresponds to the digital signature, and the said additional hash value is equal to the additional hash value obtained by applying the hash function to the previous portion of the video data stream or additional data extracted therefrom, and if the video data stream does not contain a previous part relative to the predefined part: checking whether the hash value matches the digital signature in order to determine whether the video data stream is trusted.

111. The device of claim 110, wherein if the video data stream does not contain a previous portion relative to the predetermined portion, the hash value must be checked to see if it matches the digital signature to determine whether the video data stream is trusted by checking whether the hash value and an additional hash value transmitted in the video data stream for the predetermined portion match the digital signature.

112. A device according to any one of paragraphs 88-111, configured to calculate a digital signature based on a hash value by means of: generating a verification value based on the hash value such that the hash value matches a predetermined portion of the verification value, and encrypting the verification value to obtain a digital signature, or generating a verification value based on the hash value by further hashing a predetermined value or concatenating values ​​including the predetermined value and encrypting the verification value to obtain a digital signature.

113. A device according to any one of paragraphs 88-112, configured to calculate a digital signature based on a hash value by using an asymmetric encryption scheme using a private key or a public key and a private key.

114. The device of claim 113, configured to insert extractable first information into a data stream from which an asymmetric encryption scheme can be obtained.

115. The device of claim 114, wherein the first information comprises an indicator of an encryption scheme or a first pointer to a first location from which an asymmetric encryption scheme can be determined, or a device identifier.

116. A device according to any one of paragraphs 88-115, configured to insert extractable second information into the video data stream, from which an extraction of the public key can be obtained.

117. The device of claim 116, wherein the second information comprises a second pointer to a second location from which the public key or device identifier can be retrieved.

118. The apparatus of any one of paragraphs 113-117, configured to insert a first syntax element and a second syntax element into a video data stream, wherein the second syntax element indicates a pointer to a location from which a public key can be retrieved, wherein the first syntax element has a first state and a second state, wherein the first state indicates that the location identifies exactly one public key, wherein the second state indicates that the location indicates a list of keys, wherein the apparatus is configured to, when the first syntax element is set to the second state, insert a third syntax element into the video data stream, wherein the third syntax element indicates a pointer to an entry in the list of keys.

119. A device according to any one of paragraphs 88-118, configured to insert into the data stream third information from which a hash function can be obtained.

120. The device of claim 119, wherein the third information comprises a hash function indicator or a third pointer to a third location from which the hash function can be determined, or a device identifier.

121. The device of any one of paragraphs 88-120, wherein the hash value depends on each bit of a predetermined portion of the video data stream.

122. The device according to any one of paragraphs 88-121, wherein the hash value depends on each bit of a predetermined portion of the video data stream in the entropy encoded region.

123. The apparatus of any one of paragraphs 88-122, wherein the predetermined portion of the video data stream is extended over more than one access unit of the video data stream, such that the hash value depends on bits of more than one access unit.

124. A device according to any one of paragraphs 88-123, configured to calculate a digital signature additionally based on, and due to this, a digital signature, parameterization, or identifier of the hash function.

125. The apparatus according to any one of paragraphs 88-124, wherein the predetermined portion consists of one or more portions of a video coding layer of a video data stream in which motion vectors and intra-prediction modes for prediction blocks and transform coefficients for residual blocks are encoded.

126. A method (160) for checking a video data stream (14) in which a video is encoded for a degree of trust, wherein the method comprises the steps of: apply (131) a hash function (31) to a predetermined portion of the video data stream or data extracted therefrom to obtain a hash value (33); extract (161) a digital signature (43) from the video data stream; and checking (141) whether the hash value (33) matches the digital signature (43) to determine whether the video data stream is trusted, In this case, the video is encoded into a video data stream using: encoding video into a video data stream using block-based predictive coding and transform-based residual coding by: encoding the residual data of the prediction residual block into a video data stream: by using context-adaptive binary arithmetic coding through: encoding a significance map that indicates the positions of non-zero transform coefficients in a transform block representing the residual block by, when traversing, with a forward scan, the transform coefficients of the transform block, encoding a significance flag that indicates whether a non-zero transform coefficient is located at the current position, and if so, and if the current position is not the last one in the forward scan, encoding a last significance flag that indicates whether the non-zero transform coefficient located at the current position is the last non-zero transform coefficient in the forward scan order, and encoding the values ​​of non-zero transform coefficients sequentially in reverse scanning order, reversing the direct scanning order.

127. A method (200) for decoding video from a video data stream (14), wherein the method comprises the steps of: decode (163) the digital signature (43) from the video data stream; subject the digital signature of the video data stream to verification of its trust level by: applying (131) a hash function (31) to a predetermined portion (13) of the video data stream or data (62) extracted therefrom to obtain a hash value (33), and checking (141) whether the hash value matches the digital signature to determine whether the video data stream is trusted, wherein the method comprises a step of decoding video from a video data stream by means of block-based predictive decoding and transform-based residual decoding by means of: decoding the residual data of the prediction residual block from the video data stream: by using context-adaptive binary arithmetic decoding through: decoding a significance map that indicates the positions of non-zero transform coefficients in a transform block representing the residual block by, while traversing, with a forward scan, the transform coefficients of the transform block, decoding a significance flag that indicates whether a non-zero transform coefficient is located at the current position, and if so, and if the current position is not the last one in the forward scan, decoding a last significance flag that indicates whether the non-zero transform coefficient located at the current position is the last non-zero transform coefficient in the forward scan order, and decoding the values ​​of non-zero transformation coefficients sequentially in reverse scanning order, changing the direct scanning order to the opposite.

128. A method (15) for generating a stream (14) of video data into which a video is encoded that is checked for a degree of trust, wherein the method comprises the steps of: apply (131) a hash function (31) to a predetermined portion (13) of the video data stream or data extracted therefrom to obtain a hash value (33); calculate (171) a digital signature (43) based on the hash value (33) for digitally signing the hash value (33), and insert (177) a digital signature (43) into the video data stream (14), thereby making it possible to determine whether the video data stream is trusted by checking whether the hash value (33) matches the digital signature (43), In this case, the video is encoded into a video data stream using: encoding video into a video data stream using block-based predictive coding and transform-based residual coding by: encoding the residual data of the prediction residual block into a video data stream: by using context-adaptive binary arithmetic coding through: encoding a significance map that indicates the positions of non-zero transform coefficients in a transform block representing the residual block by, when traversing, with a forward scan, the transform coefficients of the transform block, encoding a significance flag that indicates whether a non-zero transform coefficient is located at the current position, and if so, and if the current position is not the last one in the forward scan, encoding a last significance flag that indicates whether the non-zero transform coefficient located at the current position is the last non-zero transform coefficient in the forward scan order, and encoding the values ​​of non-zero transform coefficients sequentially in reverse scanning order, reversing the direct scanning order.

129. A video data stream generated by the method according to paragraph 128.