Parameter set for picture segmentation

• US 10,244,239 B2
• Filed: 12/23/2011
• Issued: 03/26/2019
• Est. Priority Date: 12/28/2010
• Status: Active Grant

• Current Assignee: Dolby Laboratories Licensing Corporation (Dolby Laboratories Incorporated)
• Original Assignee: Dolby Laboratories Licensing Corporation (Dolby Laboratories Incorporated)
• Inventors: Horowitz, Michael
• Primary Examiner(s): Kir, Albert
• Application Number:
  US13/336,675
• Publication Number:
  US 20120163453A1
• Time in Patent Office: 2,650 Days
• Field of Search: 37524024, 37524015, 37524002, 37524012, 37524008, 37524001-24009, 382243, 382240
• CPC Class Codes: C12N 9/0071 acting on paired donors with incorporation of molecular oxygen (1.14)
• CPC Class Codes: C12P 17/14 Nitrogen or oxygen as hetero atom and at least one other diverse hetero ring atom in the same ring
• CPC Class Codes: C12P 7/14 Multiple stages of fermentation; Multiple types of microorganisms or re-use of microorganisms
• CPC Class Codes: C12Y 114/00 Oxidoreductases acting on paired donors, with incorporation or reduction of molecular oxygen (1.14)
• CPC Class Codes: H04N 19/103 Selection of coding mode or of prediction mode
• CPC Class Codes: H04N 19/105 Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction
• CPC Class Codes: H04N 19/117 Filters, e.g. for pre-processing or post-processing sub-band filter banks H04N19/635
• CPC Class Codes: H04N 19/137 Motion inside a coding unit, e.g. average field, frame or block difference
• CPC Class Codes: H04N 19/139 Analysis of motion vectors, e.g. their magnitude, direction, variance or reliability
• CPC Class Codes: H04N 19/159 Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction
• CPC Class Codes: H04N 19/172 the region being a picture, frame or field
• 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 19/196 being specially adapted for the computation of encoding parameters, e.g. by averaging previously computed encoding parameters processing of motion vectors H04N19/513
• CPC Class Codes: H04N 19/436 using parallelised computational arrangements
• CPC Class Codes: H04N 19/44 Decoders specially adapted therefor, e.g. video decoders which are asymmetric with respect to the encoder
• CPC Class Codes: H04N 19/46 Embedding additional information in the video signal during the compression process H04N19/517, H04N19/68, H04N19/70 take precedence
• CPC Class Codes: H04N 19/50 using predictive coding H04N19/61 takes precedence
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/70 characterised by syntax aspects related to video coding, e.g. related to compression standards
• CPC Class Codes: H04N 19/80 Details of filtering operations specially adapted for video compression, e.g. for pixel interpolation H04N19/635, H04N19/86 take precedence
• CPC Class Codes: H04N 19/82 : involving filtering within a prediction loop
• CPC Class Codes: H04N 19/91 : Entropy coding, e.g. variable length coding [VLC] or arithmetic coding

Abstract

Systems and methods for picture segmentation through columns and slices in video encoding and decoding. A video picture is divided into a plurality of columns, each column covering only a part of the video picture in a horizontal dimension. All coded tree blocks (“CTBs”) belonging to a slice may belong to one or more columns. The columns may be used to break the same or different prediction or in-loop filtering mechanisms of the video coding, and the CTB scan order used for encoding and/or decoding may be local to a column. Column widths may be indicated in a parameter set and/or may be adjusted at the slice level. At the decoder, column width may be parsed from the bitstream, and slice decoding may occur in one or more columns.

Claims

1. A method for encoding in an encoder a bitstream of coded pictures, the method comprising:

receiving an uncoded picture;

encoding, by one or more processors, the uncoded picture into the bitstream as a first coded picture,

wherein the first coded picture comprises a plurality of coded tree blocks (CTBs),

wherein the first coded picture is segmented into at least two columns and at least two slices,

wherein each CTB belongs to both a respective column and a respective slice,

wherein a slice boundary in the first coded picture is not equal to a column boundary in the first coded picture and wherein a first slice of the at least two slices spans multiple columns, and

wherein encoding the uncoded picture is performed using both columns and slices, and wherein encoding the uncoded picture comprises;

for each of the plurality of slices, encoding the CTBs in the slice in an order that is based on the respective columns to which the CTBs in the slice belong, comprising during encoding of the first slice, breaking in-loop filtering within the first slice at each column boundary between adjacent columns of the multiple columns spanned by the first splice, wherein the CTBs in the first slice are decoded in an ordered sequence, first by CTB from left to right and top to bottom across all CTBs within a first column of the respective columns, and second by column from left to right across all the columns in the slice;

encoding, by the one or more processors and in a first picture parameter set in the bitstream, a value for a number of columns N minus one for the first coded picture of the bitstream;

encoding, by the one or more processors and in the first picture parameter set in the bitstream, column width parameters pertaining to a leftmost N−

1 columns of the first coded picture, the column width parameters being measured in units of CTBs having a first size;

encoding, by the one or more processors and in the first picture parameter set in the bitsream, a width of the first coded picture measured in units of the CTBs;

wherein the column width parameters pertaining to the leftmost N−

1 columns determine a width of a rightmost column of the first coded picture, and wherein the width of the rightmost column of the first coded picture is calculated using the width of the first coded picture in units of CTBS having the first size and the column width parameters pertaining to the N−

1 leftmost columns in units of CTBs for the first coded picture; and

transmitting, by the one or more processors, the bitstream including the first coded picture and the first picture parameter set to a decoder for reconstruction of the coded pictures in the bitstream.

2. The method of claim 1, wherein the corresponding column width of at least one column is variable between at least two rows of CTBs in the first coded picture.

3. The method of claim 2, wherein the variability is controlled by coding the corresponding column width in a slice header.

4. The method of claim 1, wherein encoding the CTBs in the slice in an order that is based on the respective columns to which the CTBs in the slice belong comprises encoding the plurality of CTBs following a scan order of CTBs, according to which the plurality of CTBs are encoded sequentially by column from left-to-right across a plurality of columns, and sequentially by CTB from left-to-right and top-to-bottom within each of the plurality of columns.

20. The method of claim 1 wherein the CTBs in the first coded picture are unevenly sized.

5. A method for decoding in a decoder a bitstream of coded pictures, the method comprising:

receiving the bitstream of coded pictures from an encoder;

obtaining, by one or more processors and from a first picture parameter set encoded in the bitstream, a value for a number of columns N minus one for a first coded picture of the bitstream,

wherein the first coded picture comprises a plurality of coded tree blocks (CTBs),

wherein the first coded picture is segmented into at least two columns and at least two slices,

wherein each CTB belongs to both a respective column and a respective slice, and

wherein a slice boundary in the first coded picture is not equal to a column boundary in the first coded picture and wherein a first slice of the two or more slices spans multiple columns;

obtaining, by the one or more processors and from the first picture parameter set encoded in the bitstream, column width parameters pertaining to a leftmost N−

1 columns of the first coded picture, the column width parameters being measured in units having a first CTB size;

determining, by the one or more processors, a width of the first coded picture in units of the first CTB size;

calculating, by the one or more processors, a width of a rightmost column of the first coded picture using the width of the first coded picture and the column width parameters pertaining to the leftmost N−

1 columns of the first coded picture; and

decoding, by the one or more processors, the first coded picture using both columns and slices, the calculated width of the rightmost column of the first coded picture, and the obtained column width for the leftmost N−

1 columns of the first coded picture to reconstruct a decoded image, comprising;

determining, for each of the CTBs in the first coded picture, a respective column to which the MB belongs using (i) the column width parameters obtained from the first picture parameter set encoded in the bitstream and (ii) the calculated width, and

for each slice in the first coded picture, decoding the CTBs in the slice in an order that is based on the respective columns to which the CTBs in the slice belong, comprising during decoding of the first slice, breaking in-loop filtering within the first slice at each column boundary between adjacent columns of the multiple columns spanned by the first slice, wherein the CTBs in the slice are decoded in an ordered sequence, first by CTB from left to right and top to bottom across all CTBs within a first column of the respective columns, and second by column from left to right across all the columns in the slice; and

outputting, by the one or more processors, the reconstructed image.

6. The method of claim 5 further comprising:

determining, from a second picture parameter set, column widths parameters pertaining to leftmost columns measured in units of a second CTB size for a second coded picture of the bitstream, the second CTB size differing from the first CTB size.

7. The method of claim 5, wherein each of the slices resides entirely within a respective column.

8. The method of claim 5, wherein sizes of the CTBs include 32×

32, 16×

16, and 8×

8 samples.

9. The method of claim 5, wherein the rightmost column for the first coded picture spans the entire vertical height of the first coded picture.

21. The method of claim 5 wherein the CTBs in the first coded picture are unevenly sized.

10. A decoder for decoding a bitstream of coded pictures, the decoder comprising:

one or more computers and one or more storage devices storing instructions that are operable, when executed by the one or more computers, to cause the one or more computers to perform operations comprising;

receiving the bitstream of coded pictures from an encoder;

obtaining, from a first picture parameter set encoded in the bitstream, a value for a number of columns N minus one for a first coded picture of the bitstream,

wherein the first coded picture comprises a plurality of coded tree blocks (CTBs),

wherein the first coded picture is segmented into at least two columns and at least two slices,

wherein each CTB belongs to both a respective column and a respective slice, and

wherein a slice boundary in the first coded picture is not equal to a column boundary in the first coded picture and wherein a first slice of the two or more slices spans multiple columns;

obtaining, from the first picture parameter set encoded in the bitstream, column width parameters pertaining to a leftmost N−

1 columns of the first coded picture, the column width parameters being measured in units having a first CTB size;

determining a width of the first coded picture in units of the first CTB size;

calculating a width of a rightmost column of the first coded picture using the width of the first coded picture and the column width parameters pertaining to the leftmost N−

1 columns of the first coded picture; and

decoding the first coded picture using both columns and slices, the calculated width of the rightmost column of the first coded picture, and the obtained column width for the leftmost N−

1 columns of the first coded picture to reconstruct a decoded image, comprising;

determining, for each of the CTBs in the first coded picture, a respective column to which the MB belongs using (i) the column width parameters obtained from the first picture parameter set encoded in the bitstream and (ii) the calculated width, and

for each slice in the first coded picture, decoding the CTBs in the slice in an order that is based on the respective columns to which the CTBs in the slice belong, comprising during decoding of the first slice, breaking in-loop filtering within the first slice at each column boundary between adjacent columns of the multiple columns spanned by the first slice, wherein the CTBs in the slice are decoded in an ordered sequence, first by CTB from left to right and top to bottom across all CTBs within a first column of the respective columns, and second by column from left to right across all the columns in the slice; and

outputting the reconstructed image.

11. The decoder of claim 10, the operations further comprising:

determining, from a second picture parameter set, column widths parameters pertaining to leftmost columns measured in units of a second CTB size for a second coded picture of the bitstream, the second CTB size differing from the first CTB size.

12. The decoder of claim 10, wherein each of the slices resides entirely within a respective column.

13. The decoder of claim 10, wherein sizes of the CTBs include 32×

32, 16×

16, and 8×

8 samples.

14. The decoder of claim 10, wherein the rightmost column for the first coded picture spans the entire vertical height of the first coded picture.

22. The decoder of claim 10 wherein the CTBs in the first coded picture are unevenly sized.

15. A non-transitory computer-readable medium storing software comprising instructions executable by one or more computers which, upon such execution, cause the one or more computers to perform operations comprising:

receiving the bitstream of coded pictures from an encoder;

obtaining, by one or more processors and from a first picture parameter set encoded in the bitstream, a value for a number of columns N minus one for a first coded picture of the bitstream,

wherein the first coded picture comprises a plurality of coded tree blocks (CTBs),

wherein the first coded picture is segmented into at least two columns and at least two slices,

wherein each CTB belongs to both a respective column and a respective slice, and

wherein a slice boundary in the first coded picture is not equal to a column boundary in the first coded picture and wherein a first slice of the two or more slices spans multiple columns;

obtaining, by the one or more processors and from the first picture parameter set encoded in the bitstream, column width parameters pertaining to a leftmost N−

1 columns of the first coded picture, the column width parameters being measured in units having a first CTB size;

determining, by the one or more processors, a width of the first coded picture in units of the first CTB size;

calculating, by the one or more processors, a width of a rightmost column of the first coded picture using the width of the first coded picture and the column width parameters pertaining to the leftmost N−

1 columns of the first coded picture; and

decoding, by the one or more processors, the first coded picture using both columns and slices, the calculated width of the rightmost column of the first coded picture, and the obtained column width for the leftmost N−

1 columns of the first coded picture to reconstruct a decoded image, comprising;

determining, for each of the CTBs in the first coded picture, a respective column to which the MB belongs using (i) the column width parameters obtained from the first picture parameter set encoded in the bitstream and (ii) the calculated width, and

for each slice in the first coded picture, decoding the CTBs in the slice in an order that is based on the respective columns to which the CTBs in the slice belong, comprising during decoding of the first slice, breaking in-loop filtering within the first slice at each column boundary between adjacent columns of the multiple columns spanned by the first slice, wherein the CTBs in the slice are decoded in an ordered sequence, first by CTB from left to right and top to bottom across all CTBs within a first column of the respective columns, and second by column from left to right across all the columns in the slice; and

outputting, by the one or more processors, the reconstructed image.

16. The computer-readable medium of claim 15 the operations further comprising:

determining, from a second picture parameter set, column widths parameters pertaining to leftmost columns measured in units of a second CTB size for a second coded picture of the bitstream, the second CTB size differing from the first CTB size.

17. The computer-readable medium of claim 15, wherein each of the slices resides entirely within a respective column.

18. The computer-readable medium of claim 15, wherein sizes of the CTBs include 32×

32, 16×

16, and 8×

8 samples.

19. The computer-readable medium of claim 15, wherein the rightmost column for the first coded picture spans the entire vertical height of the first coded picture.

23. The computer-readable medium of claim 15 wherein the CTBs in the first coded picture are unevenly sized.