Temporal domain rate distortion optimization considering coding-mode adaptive distortion propagation

Patent metadata

Field	Value
Publication number	US-11330270-B2
Application number	US-202117412292-A
Country	US
Kind code	B2
Filing date	Aug 26, 2021
Priority date	Mar 31, 2020
Publication date	May 10, 2022
Grant date	May 10, 2022

Abstract

A temporal domain rate distortion optimization considering a coding-mode adaptive distortion propagation is provided. A problem of dependency rate distortion optimization based on a temporal domain distortion propagation is induced again according to a temporal domain dependency relationship under an LD structure and a distortion propagation analysis under a skip mode and an inter mode; and an aggregation distortion of a current coding unit and an affected future coding unit are estimated and a propagation factor of a coding unit in a temporal domain distortion propagation model is calculated by constructing a time propagation chain, wherein a Lagrange multiplier is adjusted through an accurate propagation factor to realize a temporal domain dependency rate distortion optimization, and an I frame is subjected to a secondary coding technology to realize the temporal domain dependency rate distortion optimization of the I frame.

First claim

What is claimed is:

1. A temporal domain rate distortion optimization method considering a coding-mode adaptive distortion propagation, comprising the following steps:
S 1 : defining a reconstruction distortion D of a coding unit B i as:
D i =p inter ·D i inter +p skip ·D i skip =d inter +d skip ;

wherein D i inter and D i skip are coding distortions of a current coding unit selecting an inter mode and a skip mode respectively, p inter and p skip are probabilities of the current coding unit selecting the inter mode and the skip mode respectively, d inter is a first partial distortion under the inter mode, d skip is a second partial distortion under the skip mode, p inter +p skip =1;
defining p inter as:

p
inter

=

12
⁢

D
i
OMCP

12
⁢

D
i
OMCP

+

Δ
2

;

(
1
)

wherein D i OMCP =∥F i −F i−1 ∥ 2 is an original motion compensation error obtained by the coding unit B i in an original frame through a motion search, F i and F i−1 represents original pixels of the coding unit B i and a reference unit B i−1 respectively, and Δ is a quantified step size;
S 2 : when coding the coding unit B i evaluating a partial derivative on a B i temporal domain dependency rate distortion optimization problem

min

o
i

⁢

∑

j
=
i

N

⁢

⁢

E
⁡

(

D
j

)

+

λ
g

⁢

R
i

⁡

(

o
i

)

with respect to R i to obtain a global Lagrange multiplier λ g :

λ
g

=

-

∂

∑

j
=
i

N

⁢

E
⁡

(

D
j

)

∂

R
i

;

(
2
)

wherein o i is a coding parameter of the coding unit Bi and R i represents a bit number of the coding unit Bi;
multiplying a ∂R i /∂D i at both ends of formula (2) and making ∂D i /∂R i =−λ i to obtain:

λ
i

=

λ
g

/

(

1
+

∂

∑

j
=

i
+
1

N

⁢

E
⁡

(

D
j

)

Assignees

• Univ Electronic Sci & Tech China

Inventors

• Zhu Ce
• Deng Lingling
• Jiang ni
• Wang Qiuyue
• Ding Keke

Classifications

• H04N19/147 Primary

  according to rate distortion criteria (rate-distortion as a criterion for motion estimation H04N19/567) · CPC title

• H04N19/567 Primary

  Motion estimation based on rate distortion criteria · CPC title

• H04N19/172

  the region being a picture, frame or field · CPC title

• H04N19/109

  among a plurality of temporal predictive coding modes · CPC title

• H04N19/51

  Motion estimation or motion compensation · CPC title