CA2841112C

Moving picture coding and decoding using context adaptive binary arithmetic coding with fixed probability for some sample adaptive offset parameters

Abstract

A moving picture coding method includes: performing context adaptive binary arithmetic coding in which a variable probability value is used, on first information among multiple types of sample adaptive offset (SAO) information used for SAO that is a process of assigning an offset value to a pixel value of a pixel included in an image generated by coding the input image (S11); and continuously performing bypass arithmetic coding in which a fixed probability value is used, on second information and third information among the multiple types of the SAO information (S12), wherein the coded second and third information are placed after the coded first information in the bit stream.

CA2841112C, drawing sheet 1
Sheet 1 of 35

Term

6.6 yearsleft in the term

Expires 17 May 2033.

  1. Priority
  2. Filed
  3. Granted
  4. Today
  5. Expires

19 claims: 4 independent, 15 dependent

  1. 1
    The embodiments of the present invention for which an exclusive property or privilege is claimed are defined as follows:1. A moving picture coding method for coding an Input Image to generate a bit stream, the method comprising: performing context adaptive binary arithmetic coding in which a variable probability value is used, on first information among multiple types of sample adaptive offset (SAO) information used for SAO that is a process of assigning an offset value to a pixel value of a pixel included in an image generated by coding the input Image;and continuously performing bypass arithmetic coding in which a fixed probability value Is used, on second information and third information among the multiple types of the SAO Information, wherein the coded second and third information are placed after the coded first information in the bit stream, wherein a variable probability is not used in the bypass arithmetic coding.
  2. 2
    The moving picture coding method according to Claim 1, wherein one of the second information and the third information is sao_band_position indicating a range of pixel values to which the SAO is applied.
  3. 3
    The moving picture coding method according to Claim 2, wherein the other of the second information and the third information is sao_offset_sign indicating whether an offset value Is positive or negative, the offset value being assigned to a pixel value to which the SAO is applied. CA 2841112 2018-01-31
  4. 4
    The moving picture coding method according to Claim 3, wherein in the continuously performing, the sao_band_position is coded after the sao_offset_sign is coded.
  5. 5
    The moving picture coding method according to any one of Claims 1 to 4, wherein a pixel to which the SAO is applied includes components of multiple types, and the first information, the second Information, and the third Information are coded for each of the components.
  6. 6
    The moving picture coding method according to any one of Claims 1 to 5, wherein in the continuously performing, the bypass arithmetic coding is further performed on at least one other information among the multiple types of the SAO information immediately before or immediately after the coding of the second information and the third information.
  7. 7
    The moving picture coding method according to any one of Claims 1 to 6, wherein the first information is part of sao_type_idx indicating that the SAO is not to be performed or a type of the SAO.
  8. 8
    A moving picture decoding method for decoding a coded image included in a bit stream, the method comprising:performing context adaptive binary arithmetic decoding in which a variable probability value is used, on first information among multiple types of SAO information that are included in the bit stream and used for sample CA 2841112 2018-01-31 adaptive offset (SAO) which is a process of assigning an offset value to a pixel value of a pixel included in an image generated by decoding the coded image;and continuously performing bypass arithmetic decoding in which a fixed probability value is used, on second information and third information that are among the multiple types of the SAO information and located after the first information in the bit stream, wherein a variable probability is not used in the bypass arithmetic decoding.
  9. 9
    The moving picture decoding method according to Claim 8, wherein one of the second Information and the third information Is sao_band_position indicating a range of pixel values to which the SAO is applied.
  10. 10
    The moving picture decoding method according to Claim 9, wherein the other of the second information and the third information is sao_offset_sign indicating whether an offset value is positive or negative, the offset value being assigned to a pixel value to which the SAO is applied.
  11. 11
    The moving picture decoding method according to Claim 10, wherein in the continuously performing, the sao_band_position is decoded after the sao_offset_sign is decoded.
  12. 12
    The moving picture decoding method according to any one of Claims 8 to 11, wherein a pixel to which the SAO is applied includes components of multiple types, and the first information, the second information, and the third information are decoded for each of the components. CA 2841112 2018-01-31
  13. 13
    The moving picture decoding method according to any one of Claims 8 to 12, wherein in the continuously performing, the bypass arithmetic decoding is performed on at least one other information among the multiple types of the SAO information Immediately before or immediately after the decoding of the second information and the third Information.
  14. 14
    The moving picture decoding method according to any one of Claims 8 to 13, wherein the first information is part of sao_type_idx indicating that the SAO is not to be performed or a type of the SAO.
  15. 15
    A moving picture coding apparatus which comprises control circuitry and storage accessible from the control circuitry, and codes an input image to generate a bit stream, wherein the control circuitry executes the moving picture coding method according to any one of Claims 1 to 7.
  16. 16
    A moving picture decoding apparatus which comprises control circuitry and storage accessible from the control circuitry, and decodes a coded image included in a bit stream, wherein the control circuitry executes the moving picture decoding method according to any one of Claims 8 to 14.
  17. 17
    A moving picture coding and decoding apparatus comprising:the moving picture coding apparatus according to Claim 15;and the moving picture decoding apparatus according to Claim 16. CA 2841112 2018-01-31
  18. 18
    A computer readable medium having stored thereon a computer program configured to, when executed by a processor of a computing device, control the computing device to perform the moving picture coding method of any one of Claims 1 to 7.
  19. 19
    A computer readable medium having stored thereon a computer program configured to, when executed by a processor of a computing device, control the computing device to perform the moving picture decoding method of any one of Claims 8 to 14.
Independent claims19