DATA SUBSTREAM ENCAPSULATION METHOD, DE-ENCAPSULATION METHOD, AND CORRESPONDING COMPUTER PROGRAMS

• US 20120219066A1
• Filed: 10/14/2010
• Published: 08/30/2012
• Est. Priority Date: 10/23/2009
• Status: Active Grant

• Current Assignee: Orange S.A.
• Original Assignee: Orange S.A.
• Inventors: Amonou, Isabelle, Cammas, Nathalie, Pateux, Stephane, Relier, Stephanie
• Granted Patent: US 9,516,331 B2
• Time in Patent Office: Days
• US Class Current: 375/240.21
• CPC Class Codes: H04N 19/174 the region being a slice, e.g. a line of blocks or a group of blocks
• CPC Class Codes: H04N 19/436 using parallelised computational arrangements
• CPC Class Codes: H04N 19/70 characterised by syntax aspects related to video coding, e.g. related to compression standards

Abstract

A method and apparatus are provided for encapsulating a plurality of data substreams encoded in a bit stream, wherein the encoded data substream is obtained by entropy encoding of a symbol subsequence representing an image or a series of images. The method includes grouping data substreams into substream pairs according to an iterative traversal order predetermined from the plurality of substreams, and on the basis of a pair of the substreams, obtaining a symmetrical pair by reversing a data order making up the second substream of the pair. The obtained pairs are then concatenated within a sequence. The binary stream is created by encapsulating the sequence and information related to a number of substreams and related to the sizes of pairs of symmetrical substreams.

Claims

1. A method for encapsulating a plurality of substreams of data coded in a binary train, a substream of coded data being obtained by entropy coding of a sub-sequence of symbols which is representative of an image or of a series of images, said method comprising:

grouping the substreams of data into pairs of substreams according to an order of predetermined iterative scanning of said plurality of substreams;

on the basis of a pair, obtaining a symmetric pair by reversal of an order of the data making up the second substream of the pair;

concatenation of the pairs obtained into a sequence; and

creating the binary train by encapsulating said sequence and information items relating to a number of substreams and to sizes of the pairs of symmetric substreams.

2. The method for as claimed in claim 1, wherein the method comprises the following steps:

for each pair of symmetric substreams, said pair comprising a first and a second substream;

splitting the first and the second substream into fragments of fixed size;

grouping the fragments obtained in a pair of symmetric substreams into pairs of symmetric fragments by tapping off, for each pair, a first fragment in the first substream of the pair from the start of the data relating to the pair of substreams, according to a usual direction of reading, and a second fragment in the second substream of the pair from the end of the data relating to the pair of substreams, according to a reverse direction of reading; and

and wherein;

the step of concatenating the pairs into a sequence of symmetric pairs is applied to the pairs of fragments obtained and comprises tapping off the pairs of fragments arising from the pairs of substreams according to an order of predetermined iterative scanning of the pairs of substreams;

the step of creating the binary train comprises the addition of an information item relating to the fixed size of the fragments.

3. The method as claimed in claim 1, wherein the information items relating to the sizes of the pairs of symmetric substreams comprise the sizes of pairs of symmetric substreams.

4. The method as claimed in claim 2, wherein the information items relating to the sizes of the pairs of symmetric substreams comprise a number of fragments per substream and the size of the pairs of fragments comprising a last fragment of one of the substreams of a pair of symmetric substreams.

5. The method as claimed in claim 1, wherein the step of creating the binary train comprises the encapsulation of an information item relating to a mode of encapsulation of the plurality of substreams.

6. A device for encapsulating a plurality of substreams of data coded in a binary train, a substream of coded data being obtained by entropy coding of a sub-sequence of symbols which is representative of an image or of a series of images, said device comprising:

a processing device unit to;

group the substreams of data into pairs of substreams according to an order of predetermined iterative scanning of said plurality of substreams;

on the basis of a pair, obtain a symmetric pair by reversal of an order of the data making up the second substream of the pair;

concatenate the pairs obtained into a sequence; and

encapsulate said sequence and of information items relating to a number of substreams and to the sizes of the pairs of symmetric substreams.

7. The encapsulation device as claimed in claim 6, wherein the processing unit is further configured to:

for each pair of symmetric substreams, said pair comprising a first and a second substream;

split the first and of the second substream into fragments of fixed size; and

group the fragments obtained in a pair of symmetric substreams into pairs of symmetric fragments by tapping off, for each pair, a first fragment in the first substream of the pair from the start of the data relating to the pair of substreams, according to a usual direction of reading, and a second fragment in the second substream of the pair from the end of the data relating to the symmetric pair of substreams, according to a reverse direction of reading; and

apply the step of concatenating the pairs into a sequence of symmetric pairs to the pairs of fragments obtained; and

create the binary train by adding an information item relating to the fixed size of the fragments.

8. A method for de-encapsulating a binary train comprising a plurality of substreams of coded data, a substream of data being obtained by entropy coding of a sub-sequence of symbols which is representative of an image or of a series of images, wherein said de-encapsulation method comprises the following steps:

extracting information items from the binary train relating to a number of substreams and to sizes of pairs of substreams;

scanning useful data of the binary train received, in the course of which the following steps are implemented;

as long as the scanning has not finished;

identifying a start position and of an end position of a pair on the basis of said extracted information items; and

dispatching the useful data relating to the pair, said data being situated between said start and end positions, to a decoding device able to make two distinct processors perform a decoding in parallel of the useful data relating to the two elements of said pair, from said positions, the first in a usual direction and the second in a reverse direction of reading of the data.

9. The method for de-encapsulating a binary train as claimed in claim 8, wherein, in said binary train, the first and the second substreams are split into fragments of fixed size and wherein:

the step of extracting furthermore comprises extracting information items relating to the fixed size of a fragment and the identification and dispatching steps are applied to the pairs of symmetric fragments.

10. A device for de-encapsulating a binary train comprising a plurality of substreams of coded data, a substream of data being obtained by entropy coding of a sub-sequence of symbols which is representative of an image or of a series of images, said device comprising:

a processing unit configure to;

extract information items from the binary train relating to a number of substreams and to sizes of pairs of substreams;

scan useful data of the binary train received, in the course of which the following steps are implemented;

as long as the scanning has not finished;

identifying a start position and of an end position of a symmetric pair on the basis of said extracted information items;

dispatching the useful data relating to the pair situated between said start and end positions to a decoding device able to make two distinct processors perform a decoding in parallel of the useful data relating to the two elements of said pair, from said positions, the first in a usual direction and the second in a reverse direction of reading of the data.

11. The device for de-encapsulating a binary train of claim 10, wherein:

in said binary train, the first and the second substreams are split into fragments of fixed size; and

the processing unit is further configured to extract from the binary data train information items relating to the size of a fragment and to identify the start and end positions on the basis of the pairs of symmetric fragments.

12. A device for decoding a plurality of substreams of coded data, a substream of data being obtained by entropy coding of a sub-sequence of symbols which is representative of an image or of a series of images, wherein the device comprises:

first and second distinct decoding processors configured to decode in parallel with one another; and

a de-encapsulating device configured to extract information items from the binary train relating to a number of substreams and to sizes of pairs of substreams and to scan useful data of the binary train received, in the course of which the following steps are implemented as long as the scanning has not finished;

identifying a start position and of an end position of a symmetric pair on the basis of said extracted information items; and

dispatching the useful data relating to the pair situated between said start and end positions to the first and second distinct decoding processors, which are configured to perform a decoding in parallel of the useful data relating to the two elements of said pair, from said positions, the first in a usual direction and the second in a reverse direction of reading of the data.

13. (canceled)

14. A non-transitory computer readable medium comprising a computer program or stored thereon, which comprises program code instructions for performing a method of encapsulating a plurality of substreams of data coded in a binary train, a substream of coded data being obtained by entropy coding of a sub-sequence of symbols which is representative of an image or of a series of images, when said instructions are executed by a processor, wherein the instructions comprise:

instructions configured to group the substreams of data into pairs of substreams according to an order of predetermined iterative scanning of said plurality of substreams;

instructions configured to, on the basis of a pair, obtain a symmetric pair by reversal of an order of the data making up the second substream of the pair;

instructions configured to concatenate the pairs obtained into a sequence; and

instructions configured to create the binary train by encapsulating said sequence and information items relating to a number of substreams and to sizes of the pairs of symmetric substreams.

15. A non-transitory computer readable medium comprising a computer program stored thereon, which comprises program code instructions for performing a method of de-encapsulating a binary train comprising a plurality of substreams of coded data, a substream of data being obtained by entropy coding of a sub-sequence of symbols, which is representative of an image or of a series of images, when said instructions are executed by a processor, wherein the instructions comprise:

instructions configured to extract information items from the binary train relating to a number of substreams and to sizes of pairs of substreams;

instructions configured to scan useful data of the binary train received, in the course of which the following steps are implemented;

as long as the scanning has not finished;

identifying a start position and of an end position of a pair on the basis of said extracted information items; and

dispatching the useful data relating to the pair, said data being situated between said start and end positions, to a decoding device able to make two distinct processors perform a decoding in parallel of the useful data relating to the two elements of said pair, from said positions, the first in a usual direction and the second in a reverse direction of reading of the data.