How to encode frames in decoding order?

[jess4]

NV_ENC_PIC_PARAMS picParams{};
  picParams.pictureType = output.picType == 'I'   ? NV_ENC_PIC_TYPE_IDR
                          : output.picType == 'P' ? NV_ENC_PIC_TYPE_P
                                                  : NV_ENC_PIC_TYPE_B;
  picParams.frameIdx = output.decodingOrderIdx;
  picParams.codecPicParams.hevcPicParams.displayPOCSyntax = 2 * output.displayOrderIdx;
  picParams.codecPicParams.hevcPicParams.refPicFlag = output.refPicFlag;

  pEnc->EncodeFrame(vPacket, &picParams);

I tried using this code where I developed my own GOP structure generation algorithm and applied it to NVENC encoding.

However, it didn’t work as expected, and the output exhibited reference picture mismatches.

How can I encode frames in the order of decoding? I intend to use this function for iterative encoding.

Additionally, this is GOP structure what i used. (bframes=7, keyframe Interval=53)

decoding(encoding) order	display order	picture type
0	0	I
1	8	P
2	4	B
3	1	B
4	2	B
5	3	B
6	5	B
7	6	B
8	7	B
9	16	P
10	12	B
11	9	B
12	10	B
13	11	B
14	13	B
15	14	B
16	15	B
17	24	P
18	20	B
19	17	B
20	18	B
21	19	B
22	21	B
23	22	B
24	23	B
25	32	P
26	28	B
27	25	B
28	26	B
29	27	B
30	29	B
31	30	B
32	31	B
33	40	P
34	36	B
35	33	B
36	34	B
37	35	B
38	37	B
39	38	B
40	39	B
41	48	P
42	44	B
43	41	B
44	42	B
45	43	B
46	45	B
47	46	B
48	47	B
49	52	P
50	50	B
51	49	B
52	51	B
53	53	I

[jess4]

I resolved this issues with
replacing
picParams.codecPicParams.hevcPicParams.displayPOCSyntax = 2 * output.displayOrderIdx;
to
picParams.codecPicParams.hevcPicParams.displayPOCSyntax = 2 * (output.displayOrderIdx % keyFrameInterval);