1. JCTVC-I0358: Truncated EG0 coding method
Seung-Hwan Kim, Louis Kerofsky,
Andrew Segall 1 1

2. EG0 in HM6.0 EG0 code is employed after Golomb-Rice (G-R) coding
The longest (worst case) codeword length is “29 bins”
Input symbol
(Value)
Prefix
Suffix
Total Length of code words
Number
Of code words
Cumulative Number of code words 1 20
1, 2
21-1 ~ 22-2 x 3 21
22 -1
3 ~ 6
22-1 ~ 23-2 11 xx 5 22
23 -1
7 ~ 14
23-1 ~ 24-2
111
xxx 7 23
24 -1
15 ~ 30
24-1 ~ 25-2
1111
xxxx 9 24
25 -1
31 ~ 62
25-1 ~ 26-2
11111
xxxxx 25
26 -1
63 ~ 126
26-1 ~ 27-2
111111
xxxxxx 13 26
27 -1
127 ~ 254
27-1 ~ 28-2
xxxxxxx 15 27
28 -1
255 ~ 510
28-1 ~ 29-2
xxxxxxxx 17 28
29 -1
511 ~ 1022
29-1 ~
xxxxxxxxx 19 29
210 -1
1023 ~ 2046 ~
xxxxxxxxxx
210
211 -1
2047 ~ 4095 ~
xxxxxxxxxxx
211
212 -1
4095 ~ 8191 ~
xxxxxxxxxxxx
212
213 -1
8191 ~ ~
xxxxxxxxxxxxx
213
214 -1 ~ ~
xxxxxxxxxxxxxx
214
215 -1 2 2

3. Proposed EG0
Invention
Propose to truncate EG0 at a certain point and reduce the worst case code word length
Truncate the EG0 code when input value is greater than 254
The longest (worst case) codeword length is “24 bins” which is shorter than the conventional case (29 bins)
Input symbol
(Value)
Prefix
Suffix
Total Length of
code words
Number
Of code words
Cumulative Number of code words 1 20
1, 2
21-1 ~ 22-2 x 3 21
22 -1
3 ~ 6
22-1 ~ 23-2 11 xx 5 22
23 -1
7 ~ 14
23-1 ~ 24-2
111
xxx 7 23
24 -1
15 ~ 30
24-1 ~ 25-2
1111
xxxx 9 24
25 -1
31 ~ 62
25-1 ~ 26-2
11111
xxxxx 25
26 -1
63 ~ 126
26-1 ~ 27-2
111111
xxxxxx 13 26
27 -1
127 ~ 254
27-1 ~ 28-2
xxxxxxx 15 27
28 -1
255 ~
28-1 ~
xxxxxxxxxxxxxxx
215

4. Implemented the proposed method into HM 6.0
Results
Implemented the proposed method into HM 6.0
Test 1: common test condition (QP=22,27,32,37)
Test 2: low QP test condition (QP=1,5,9,13)
Main
HE10 Y U V
All Intra
0.0% RA LD
Main
HE10 Y U V
All Intra
0.0% RA
0.1% LD 4

5. Reduce the size of worst case codeword from EG0
Conclusion
Reduce the size of worst case codeword from EG0
29 bins  24 bins
Coding performance
No changes in common test condition and high bitrate coding (low QP) condition 5 5