GB2456486A - Regenerating lost or corrupted primary frames based on further primary and secondary frames - Google Patents
Regenerating lost or corrupted primary frames based on further primary and secondary frames Download PDFInfo
- Publication number
- GB2456486A GB2456486A GB0622979A GB0622979A GB2456486A GB 2456486 A GB2456486 A GB 2456486A GB 0622979 A GB0622979 A GB 0622979A GB 0622979 A GB0622979 A GB 0622979A GB 2456486 A GB2456486 A GB 2456486A
- Authority
- GB
- United Kingdom
- Prior art keywords
- frame
- primary
- frames
- data rate
- picture
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
- H04N19/85—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using pre-processing or post-processing specially adapted for video compression
- H04N19/89—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using pre-processing or post-processing specially adapted for video compression involving methods or arrangements for detection of transmission errors at the decoder
- H04N19/895—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using pre-processing or post-processing specially adapted for video compression involving methods or arrangements for detection of transmission errors at the decoder in combination with error concealment
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
- H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
- H04N19/102—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or selection affected or controlled by the adaptive coding
- H04N19/103—Selection of coding mode or of prediction mode
- H04N19/107—Selection of coding mode or of prediction mode between spatial and temporal predictive coding, e.g. picture refresh
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
- H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
- H04N19/169—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding
- H04N19/17—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object
- H04N19/172—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object the region being a picture, frame or field
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
- H04N19/50—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding
- H04N19/503—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding involving temporal prediction
- H04N19/51—Motion estimation or motion compensation
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
- H04N19/50—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding
- H04N19/503—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding involving temporal prediction
- H04N19/51—Motion estimation or motion compensation
- H04N19/513—Processing of motion vectors
- H04N19/517—Processing of motion vectors by encoding
- H04N19/52—Processing of motion vectors by encoding by predictive encoding
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
- H04N19/50—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding
- H04N19/503—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding involving temporal prediction
- H04N19/51—Motion estimation or motion compensation
- H04N19/53—Multi-resolution motion estimation; Hierarchical motion estimation
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
- H04N19/60—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using transform coding
- H04N19/61—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using transform coding in combination with predictive coding
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
- H04N19/85—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using pre-processing or post-processing specially adapted for video compression
- H04N19/89—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using pre-processing or post-processing specially adapted for video compression involving methods or arrangements for detection of transmission errors at the decoder
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
- H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
- H04N19/134—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or criterion affecting or controlling the adaptive coding
- H04N19/136—Incoming video signal characteristics or properties
- H04N19/137—Motion inside a coding unit, e.g. average field, frame or block difference
Abstract
A method of generating a robust archive digital video copy representing a picture sequence comprises: generating a primary encoded frame for each picture at a first, higher data rate, the primary frame capable of being decoded without reference to any other primary frame; and generating, for each primary frame, a secondary frame at a second, lower data rate, representing difference information between that primary frame and one or more other primary frames. On loss of or error in any primary frame, a picture representation associated with that primary frame can be decoded from the associated secondary frame and one or more other primary frames. A corresponding apparatus is also independently claimed, as is a method and apparatus for extracting digital video from an archive copy in which such primary frames are monitored 22 for loss or error and, where necessary, regenerated based on the secondary frame and another primary frame(s). Difference information may be motion vectors and differences from motion compensated prediction.
Description
2456486
ARCHIVING OF DIGITAL VIDEO
The invention relates to the archiving of digital video.
There is a clear need for archive storage techniques which optimise the often competing demands of quality of reproduction, robustness against error and 5 efficiency in digital bit rate.
Data compression techniques for digital video are well established. Typically, a combination of techniques will be employed, depending on the degree of compression required. A moderate degree of compression can be achieved for example with a carefully chosen transformation and run-length coding. Exploiting 10 temporal redundancies and coding differences between successive pictures can achieve higher levels of compression. Typically, a motion compensated prediction from one or more reference frames (or in the case of interlaced video, one or more reference fields) is formed, with errors in the prediction, together with the motion vectors employed in the prediction, being transmitted in place of the 15 pictu.r9 its®!?. Th®S® t®Chn!C]'j®? ?r® C* CO' ,r<?p p*pmnlifi«rl in the wirielv emDloved MPEG compression standards. So called "l-frames" or, in the case of interlaced video, "l-fields" are intra- encoded, that is to say without reference to any other frame or field. P-frames/fields and B-frames/fields are prediction encoded,, with P- frames/fields predicted from one or more temporally prior reference 20 frames/fields, and B- frames/fields from both earlier and later reference frames/fields.
For ease of understanding, in the remainder of this document the term "frames" will be used to mean either frames or fields, as appropriate.
Error-correcting codes are similarly well established in the general area of data 25 compression. Work has been done in combining appropriate error correcting techniques with video compression to meet the competing demands outlined above. However, complex processing is often involved in either or both of the encoding and decoding operations.
It would be an advantage if robustness in digital video archiving could be 30 achieved without the complex processing that is normally involved in efficient error correction.
-2-
Accordingly, the present invention consists in one aspect in a method of generating a robust archive copy of digital video representing a sequence of pictures, the method comprising the steps of generating a primary encoded frame for each picture at a first, higher data rate, which primary frame is capable of 5 being decoded without reference to any other encoded frame to provide a high quality representation of the associated picture, and generating for each primary frame a secondary frame at a second, lower data rate, which secondary frame represents difference information between that primary frame and one or more other primary frames, such that on loss of or error in any primary frame, a 10 representation of the picture associated with that primary frame can be decoded from the associated secondary frame and said one or more other primary frames.
Advantageously, said difference information comprises motion vectors and differences from a motion compensated prediction.
The second data rate may be between 5% and 50%; between 10% and 30% or 15 around 20% of the first data rate.
In another aspect, the present invention consists in apparatus for generating a robust archive copy of digital video representing a sequence of pictures, comprising an intra-frame encoder for generating a primary encoded frame for each picture at a first, higher data rate, which primary frame is capable of being 20 decoded without reference to any other encoded frame to provide a high quality representation of the associated picture; means for generating for each primary frame a secondary frame at a second, lower data rate, which secondary frame represents difference information between that primary frame and one or more other primary frames, such that on loss of or error in any primary frame, a 25 representation of the picture associated with that primary frame can be decoded from the associated secondary frame and said one or more other primary frames and means for associating each secondary frame with the primary frame in storage.
In yet another aspect, the present invention consists in a method for extracting 30 digital video from an archive copy in storage, the archive copy comprising a primary encoded frame for each picture at a first, higher data rate, which primary frame is capable of being decoded without reference to any other encoded frame to provide a high quality representation of the associated picture and for each
-3-
primary frame a secondary frame at a second, lower data rate, which secondary frame represents difference information between that primary frame and one or more other primary frames, such that on loss of or error in any primary frame, a representation of the picture associated with that primary frame can be decoded 5 from the associated secondary frame and said one or more other primary frames, the method comprising the steps of monitoring primary frames for loss or error; where necessary, regenerating a primary frame from the associated secondary frame and said one or more other primary frames.
In still yet another aspect, the present invention consists in apparatus for 10 extracting digital video from an archive copy in storage, the archive copy comprising a primary encoded frame for each picture at a first, higher data rate, which primary frame is capable of being decoded without reference to any other encoded frame to provide a high quality representation of the associated picture and for each primary frame a secondary frame at a second, lower data rate, 15 which secondary frame represents difference information between that primary frHrv, * one or < > »ere other p> ■■ nur^ numoo, uiai un iu?o Ot oi cfi Oi m oiiy primary frame, a representation of the picture associated with that primary frame can be decoded from the associated secondary frame and said one or more other primary frames, the apparatus comprising means for monitoring primary frames 20 for loss or error; and means for regenerating a primary frame from the associated secondary frame and said one or more other primary frames.
Examples of the present invention may make use of existing, well-understood video compression technologies to provide a robust archive copy. Lost or damaged primary frames can be regenerated from the secondary and associated 25 primary frames in a manner analogous to the decoding of prediction-coded video. Complexities arising from the interplay of different compression and error-correction technologies are avoided.
The secondary frames can be interleaved with the primary frames in a single file. In one alternative, the secondary files form a separate file. Means may be 30 provided for associating each secondary file with the appropriate primary files.
This may take the form of metadata.
The secondary frame for one primary frame may contain difference information relating to two other primary frames, in particular using both earlier and later
-4-
frames tor bi-directional prediction in the manner of a B-trame in conventional MPEG. In one alternative, each secondary frame may contain difference information relating to only one other primary frame, in the manner of a P-frame in conventional MPEG. In another alternative, a secondary frame may contain 5 difference information relating to two or more other primary frames, lying temporally to the same side of the associate primary frame.
Loss or error to secondary frame data may also occur, causing the secondary frames to be unsuitable for protecting primary frame data. In such circumstances, the secondary frame data may be re-generated from the primary frame data.
10 The invention will now be described by way of example with reference to the accompanying drawings in which:
Figure 1 is a block diagram of apparatus for generating an archive copy of digital video, according to one embodiment.
Figure 2 is a block diagram of apparatus for extracting digital video from IS on ai'ci'iivo Cufjy in siuiiiyti, according to one emoooiment.
Referring to Figure 1, digital video is compression encoded in intra-frame encoder 10. This may be a generally conventional encoder - utilising for example MPEG-2; MPEG AVC/H.264; motion JPEG; H.261 or H.263 - operating at a high data rate to ensure high quality. Typical data rates may be between 50 and 80 Mb/s 20 for standard definition video. The output of the intra frame encoder will be a sequence of primary encoded frames (in this example referred to as l-frames), one for each picture, which primary frame is capable of being decoded without reference to any other encoded frame to provide a high quality representation of the associated picture.
25 Motion compensated predictor 12 serves to produce for each primary frame (I-frame), a secondary frame that represents difference information between that primary frame and one or more other primary frames. In this example, such secondary frames will be referred to as E-frames. If the series of l-frames is designated l0 li l2---li, the E-frame Ej associated with l-frame li may represent 30 difference information between lj and Im and/or difference information between I, and Li. The coding approach taken in the production of these E-frames may resemble that of MPEG B-frames, in which forward or backward motion compensated prediction is employed. The data rate for the E-frames will be
-5-
chosen as a design compromise between the bit rate overhead and the quality required in any regenerated l-frame. The data rate for standard definition may be between 10 and 16 Mb/s.
l-frames and E-frames are taken to frame combiner 14, which controls the writing 5 of the l-frame and E-frame sequences to storage 18. RAID technology will typically be employed to improve robustness. The l-frames and E-frames may be treated as separate files, with appropriate metadata or other means for associating the respective I- and E-frames. In an alternative, the l-frames and E-frames may be interleaved in a single file. In the writing strategy, care may be 10 taken to reduce the probability of simultaneous loss of an l-frame and its associated E-frame.
Turning to Figure 2, when reading from storage 18, the frame de-combiner 20 operates to form separate sequences of l-frames and E-frames. The l-frames are checked for data integrity in unit 22 and in the normal course pass to the intra-15 frame decoder 24. This intra-frame decoder 24 may be of conventional form.
In the cvcni oi ioss ui ut damage to an i-Trame ijf unit 26 will act to reconstruct the l-frame, taking information from E,and, as appropriate, In and/or li+1. That is to say, motion vectors in Ei will be employed to form a motion compensated prediction from In or li+1 with differences again taken from Ei being combined with 20 prediction to form an output.
Whilst the elements 22, 24 and 26 have been depicted separately in the diagram, it will be understood that an appropriately configured decoder may provide all their functions.
It will often be convenient to employ the same compression technologies and file 25 formats for both the l-frames and the E-frames. In an arrangement in which I-frames and E-frames are interleaved, it may sometimes be convenient to configure the resulting I E I E sequence as a compliant stream in the protocol concerned, with the E-frames flagged as not for display.
Whilst, the example has been given of E-frames coded as forward and backward 30 predictions from neighbouring l-frames, it should be understood that numerous alternatives exist. Single sided prediction can be employed, from one or multiple reference frames. If a number of adjacent frames of the original data were lost, this would allow for regeneration by successive reconstruction from one side.
-6-
Where frame data is not at a constant bit rate per frame, there may be an advantage in predicting from prior frames only and maintaining a buffer of previously decoded data representing a number of previous frames.
The described principle of prediction could apply to predicting blocks in a given 5 frame, either from spatially adjacent blocks in the same frame or from blocks, particularly co-located blocks, in adjacent frames.
-7-
Claims (12)
1. A method of generating a robust archive copy of digital video representing a sequence of pictures, the method comprising the steps of generating a primary encoded frame for each picture at a first, higher data rate, which primary frame is capable of being decoded without reference to any other encoded frame to provide a high quality representation of the associated picture and generating for each primary frame a secondary frame at a second, lower data rate, which secondary frame represents difference information between that primary frame and one or more other primary frames, such that on loss of or error in any primary frame, a representation of the picture associated with that primary frame can be decoded from the associated secondary frame and said one or more other primary frames.
2. A method according to Claim 1, wherein said difference information comprises moiion vectors ana differences from a motion compensated prediction.
3. A method according to Claim 1 or Claim 2, wherein the second data rate is between 5% and 50% of the first data rate.
4. A method according to Claim 3, wherein the second data rate is between 10% and 30% and preferably around 20% of the first data rate.
5. Apparatus for generating a robust archive copy of digital video representing a sequence of pictures, comprising an intra-frame encoder for generating a primary encoded frame for each picture at a first, higher data rate, which primary frame is capable of being decoded without reference to any other encoded frame to provide a high quality representation of the associated picture; means for generating for each primary frame a secondary frame at a second, lower data rate, which secondary frame represents difference information between that primary frame and one or more other primary frames, such that on loss of or error in any primary frame, a representation of the picture associated with that primary frame can be decoded from the associated secondary frame and
-8-
said one or more other primary frames and means for associating each secondary frame with the primary frame in storage.
6. Apparatus according to Claim 5, further comprising means for distributing primary and secondary frames with redundancy across multiple storage elements.
7. Apparatus according to Claim 5 or Claim 6, further comprising means for distributing primary and secondary frames in storage so as to reduce the likelihood of simultaneous loss of both a primary frame and its associated secondary frame.
8. Apparatus according to any one of Claims 5 to 7, wherein said difference information comprises motion vectors and differences from a motion compensated prediction.
9. Apparatus according to any one of Claims 5 to 8, wherein the second data rate is between 5% and 50% of the first data rate
10. Apparatus according to Claim 9, wherein the second data rate is between 10% and 30% and preferably around 20% of the first data rate.
11. A method for extracting digital video from an archive copy in storage, the archive copy comprising a primary encoded frame for each picture at a first, higher data rate, which primary frame is capable of being decoded without reference to any other encoded frame to provide a high quality representation of the associated picture and for each primary frame a secondary frame at a second, lower data rate, which secondary frame represents difference information between that primary frame and one or more other primary frames, such that on loss of or error in any primary frame, a representation of the picture associated with that primary frame can be decoded from the associated secondary frame and said one or more other primary frames, the method comprising the steps of monitoring primary frames for loss or error; where necessary,
regenerating a primary frame from the associated secondary frame and said one or more other primary frames.
-9-
12. Apparatus for extracting digital video from an archive copy in storage, the archive copy comprising a primary encoded frame for each picture at a first, higher data rate, which primary frame is capable of being decoded without reference to any other encoded frame to provide a high quality representation of the associated picture and for each primary frame a secondary frame at a second, lower data rate, which secondary frame represents difference information between that primary frame and one or more other primary frames, such that on loss of or error in any primary frame, a representation of the picture associated with that primary frame can be decoded from the associated secondary frame and said one or more other primary frames, the apparatus comprising means for monitoring primary frames for loss or error; and means for regenerating a primary frame from the associated secondary frame and said one or more other primary frames.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB0622979A GB2456486B (en) | 2006-11-17 | 2006-11-17 | Archiving of digital video |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB0622979A GB2456486B (en) | 2006-11-17 | 2006-11-17 | Archiving of digital video |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB0622979D0 GB0622979D0 (en) | 2006-12-27 |
| GB2456486A true GB2456486A (en) | 2009-07-22 |
| GB2456486B GB2456486B (en) | 2011-01-26 |
Family
ID=37605494
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB0622979A Expired - Fee Related GB2456486B (en) | 2006-11-17 | 2006-11-17 | Archiving of digital video |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2456486B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104954807A (en) * | 2015-06-25 | 2015-09-30 | 西安理工大学 | Video copy tamper detection method resisting geometric attacks |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5384598A (en) * | 1992-10-20 | 1995-01-24 | International Business Machines Corporation | System and method for frame differencing video compression and decompression with frame rate scalability |
| GB2353654A (en) * | 1999-08-26 | 2001-02-28 | Sony Uk Ltd | Processing GOPs to be stored as all I-frames |
-
2006
- 2006-11-17 GB GB0622979A patent/GB2456486B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5384598A (en) * | 1992-10-20 | 1995-01-24 | International Business Machines Corporation | System and method for frame differencing video compression and decompression with frame rate scalability |
| GB2353654A (en) * | 1999-08-26 | 2001-02-28 | Sony Uk Ltd | Processing GOPs to be stored as all I-frames |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104954807A (en) * | 2015-06-25 | 2015-09-30 | 西安理工大学 | Video copy tamper detection method resisting geometric attacks |
| CN104954807B (en) * | 2015-06-25 | 2018-02-23 | 西安理工大学 | The video dubbing altering detecting method of resist geometric attackses |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2456486B (en) | 2011-01-26 |
| GB0622979D0 (en) | 2006-12-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3923898B2 (en) | Image coding method and apparatus | |
| KR101425602B1 (en) | Method and apparatus for encoding/decoding image | |
| JP5722943B2 (en) | Redundant video encoding method and apparatus | |
| EP1867176A1 (en) | Method for decoding video signal encoded using inter-layer prediction | |
| Baccichet et al. | Systematic lossy error protection based on H. 264/AVC redundant slices and flexible macroblock ordering | |
| TWI737217B (en) | Dynamic image prediction and decoding method | |
| US8335252B2 (en) | Method and apparatus for encoding groups of pictures of a video sequence, each of said groups including an intra encoded picture and more than two encoded pictures | |
| GB2456486A (en) | Regenerating lost or corrupted primary frames based on further primary and secondary frames | |
| Liu et al. | Low-delay distributed multiple description coding for error-resilient video transmission | |
| US20220078457A1 (en) | Systems, methods, and articles for adaptive lossy decoding | |
| JP4555186B2 (en) | Digital video decoding apparatus and digital video decoding method | |
| Kumar et al. | Key frame quantisation error reduction in distributed video coding | |
| JP2007151163A (en) | Image decoding method and apparatus | |
| JP2006141045A (en) | Moving picture decoding apparatus and method | |
| JP2006141044A (en) | Moving picture coding apparatus and method | |
| JPH0746604A (en) | Error concealing device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20141117 |