Skipping NAL unit 63

[jriker1]

I am trying to re-encode a 4k HDR10/Dolby Vision show.

This is the info from mediainfo:

colour_description_present               : Yes
colour_description_present_Source        : Stream
Color range                              : Limited
colour_range_Source                      : Stream
Color primaries                          : BT.2020
colour_primaries_Source                  : Stream
Transfer characteristics                 : PQ
transfer_characteristics_Source          : Stream
Matrix coefficients                      : BT.2020 non-constant
matrix_coefficients_Source               : Stream
Mastering display color primaries        : Display P3
MasteringDisplay_ColorPrimaries_Source   : Stream
Mastering display luminance              : min: 0.0001 cd/m2, max: 1000 cd/m2
MasteringDisplay_Luminance_Source        : Stream
Maximum Content Light Level              : 1000 cd/m2
MaxCLL_Source                            : Stream
Maximum Frame-Average Light Level        : 719 cd/m2
MaxFALL_Source                           : Stream
Original source medium                   : Blu-ray

This is the info from ffprobe:

    "frames": [
        {
            "media_type": "video",
            "stream_index": 0,
            "key_frame": 1,
            "pts": 0,
            "pts_time": "0.000000",
            "best_effort_timestamp": 0,
            "best_effort_timestamp_time": "0.000000",
            "pkt_duration": 41,
            "pkt_duration_time": "0.041000",
            "duration": 41,
            "duration_time": "0.041000",
            "pkt_pos": "8497",
            "pkt_size": "3325",
            "width": 3840,
            "height": 2160,
            "crop_top": 0,
            "crop_bottom": 0,
            "crop_left": 0,
            "crop_right": 0,
            "pix_fmt": "yuv420p10le",
            "sample_aspect_ratio": "1:1",
            "pict_type": "I",
            "coded_picture_number": 0,
            "display_picture_number": 0,
            "interlaced_frame": 0,
            "top_field_first": 0,
            "repeat_pict": 0,
            "color_range": "tv",
            "color_space": "bt2020nc",
            "color_primaries": "bt2020",
            "color_transfer": "smpte2084",
            "chroma_location": "topleft",
            "tags": {
                "timecode": "00:59:58:08"
            },
            "side_data_list": [
                {
                    "side_data_type": "Mastering display metadata",
                    "red_x": "34000/50000",
                    "red_y": "16000/50000",
                    "green_x": "13250/50000",
                    "green_y": "34500/50000",
                    "blue_x": "7500/50000",
                    "blue_y": "3000/50000",
                    "white_point_x": "15635/50000",
                    "white_point_y": "16450/50000",
                    "min_luminance": "1/10000",
                    "max_luminance": "10000000/10000"
                },
                {
                    "side_data_type": "Content light level metadata",
                    "max_content": 1000,
                    "max_average": 719
                },
                {
                    "side_data_type": "SMPTE 12-1 timecode",
                    "timecodes": [
                        {
                            "value": "00:59:58:08"
                        }
                    ]
                },
                {
                    "side_data_type": "Dolby Vision RPU Data"
                },
                {
                    "side_data_type": "Dolby Vision Metadata",
                    "rpu_type": 2,
                    "rpu_format": 18,
                    "vdr_rpu_profile": 1,
                    "vdr_rpu_level": 0,
                    "chroma_resampling_explicit_filter_flag": 0,
                    "coef_data_type": 0,
                    "coef_log2_denom": 23,
                    "vdr_rpu_normalized_idc": 1,
                    "bl_video_full_range_flag": 0,
                    "bl_bit_depth": 10,
                    "el_bit_depth": 10,
                    "vdr_bit_depth": 12,
                    "spatial_resampling_filter_flag": 0,
                    "el_spatial_resampling_filter_flag": 1,
                    "disable_residual_flag": 0,
                    "vdr_rpu_id": 0,
                    "mapping_color_space": 0,
                    "mapping_chroma_format_idc": 0,
                    "nlq_method_idc": 0,
                    "nlq_method_idc_name": "linear_dz",
                    "num_x_partitions": 2047,
                    "num_y_partitions": 1,
                    "components": [
                        {
                            "pivots": "0 128 256 384 512 640 768 896 1023",
                            "pieces": [
                                {
                                    "mapping_idc": 0,
                                    "mapping_idc_name": "polynomial",
                                    "poly_order": 1,
                                    "poly_coef": "0 8388608"
                                },
                                {
                                    "mapping_idc": 0,
                                    "mapping_idc_name": "polynomial",
                                    "poly_order": 1,
                                    "poly_coef": "0 8388608"
                                },
                                {
                                    "mapping_idc": 0,
                                    "mapping_idc_name": "polynomial",
                                    "poly_order": 1,
                                    "poly_coef": "0 8388608"
                                },
                                {
                                    "mapping_idc": 0,
                                    "mapping_idc_name": "polynomial",
                                    "poly_order": 1,
                                    "poly_coef": "0 8388608"
                                },
                                {
                                    "mapping_idc": 0,
                                    "mapping_idc_name": "polynomial",
                                    "poly_order": 1,
                                    "poly_coef": "0 8388608"
                                },
                                {
                                    "mapping_idc": 0,
                                    "mapping_idc_name": "polynomial",
                                    "poly_order": 1,
                                    "poly_coef": "0 8388608"
                                },
                                {
                                    "mapping_idc": 0,
                                    "mapping_idc_name": "polynomial",
                                    "poly_order": 1,
                                    "poly_coef": "0 8388608"
                                },
                                {
                                    "mapping_idc": 0,
                                    "mapping_idc_name": "polynomial",
                                    "poly_order": 1,
                                    "poly_coef": "0 8388608"
                                }
                            ],
                            "nlq_offset": 512,
                            "vdr_in_max": 1048576,
                            "linear_deadzone_slope": 2048,
                            "linear_deadzone_threshold": 0
                        },
                        {
                            "pivots": "0 1023",
                            "pieces": [
                                {
                                    "mapping_idc": 1,
                                    "mapping_idc_name": "mmr",
                                    "mmr_order": 3,
                                    "mmr_constant": 0,
                                    "mmr_coef": "0 6391320 0 0 0 0 0 0 3195660 0 0 0 0 0 0 1597830 0 0 0 0 0"
                                }
                            ],
                            "nlq_offset": 512,
                            "vdr_in_max": 1048576,
                            "linear_deadzone_slope": 2048,
                            "linear_deadzone_threshold": 0
                        },
                        {
                            "pivots": "0 1023",
                            "pieces": [
                                {
                                    "mapping_idc": 1,
                                    "mapping_idc_name": "mmr",
                                    "mmr_order": 3,
                                    "mmr_constant": 0,
                                    "mmr_coef": "0 0 6391320 0 0 0 0 0 0 3195660 0 0 0 0 0 0 1597830 0 0 0 0"
                                }
                            ],
                            "nlq_offset": 512,
                            "vdr_in_max": 1048576,
                            "linear_deadzone_slope": 2048,
                            "linear_deadzone_threshold": 0
                        }
                    ],
                    "dm_metadata_id": 0,
                    "scene_refresh_flag": 1,
                    "ycc_to_rgb_matrix": "9574/8192 0/8192 13802/8192 9574/8192 -1540/8192 -5348/8192 9574/8192 17610/8192 0/8192",
                    "ycc_to_rgb_offset": "16777216/268435456 134217728/268435456 134217728/268435456",
                    "rgb_to_lms_matrix": "7222/16384 8771/16384 390/16384 2654/16384 12430/16384 1300/16384 0/16384 422/16384 15962/16384",
                    "signal_eotf": 65535,
                    "signal_eotf_param0": 0,
                    "signal_eotf_param1": 0,
                    "signal_eotf_param2": 0,
                    "signal_bit_depth": 12,
                    "signal_color_space": 0,
                    "signal_chroma_format": 0,
                    "signal_full_range_flag": 1,
                    "source_min_pq": 62,
                    "source_max_pq": 3696,
                    "source_diagonal": 42
                }

I ran dovi_tool with -m 2 against the HEVC source. When I ran the ffmpeg encode with:

ffmpeg -i Minions.The.Rise.of.Gru.2022.2160p.BluRay.REMUX.HEVC.DTS-HD.MA.TrueHD.7.1.Atmos-FGT.mkv -sn -an -f yuv4mpegpipe -strict -1 -pix_fmt yuv420p10le - | x265-10b - --input-depth 10 --output-depth 10 --y4m --preset slow --hdr10 --hdr10-opt --high-tier --repeat-headers --crf 20 --master-display "G(13250,34500)B(7500,3000)R(34000,16000)WP(15635,16450)L(10000000,1)" --max-cll "1000,719" --chromaloc 2 --no-sao --range limited --keyint 24 --colormatrix bt2020nc --colorprim bt2020 --transfer smpte2084 --dolby-vision-rpu RPU.bin --dolby-vision-profile 8.1 --vbv-bufsize 160000 --vbv-maxrate 160000 Minions.The.Rise.of.Gru.2022-converted.hevc

It started screaming constantly with

[hevc @ 0000027f5cdb7380] Skipping NAL unit 63
    Last message repeated 9 times
[hevc @ 0000027f5cdb3780] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb5780] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb5f80] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb3380] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb9f80] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb7780] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb8f80] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb9780] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb4f80] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb3b80] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb6380] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb4b80] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb5b80] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb8380] Skipping NAL unit 63
    Last message repeated 2 times
[hevc @ 0000027f5cdb7b80] Skipping NAL unit 63
    Last message repeated 2 times

Was hoping as the creator of this super helpful tool you would know what is happening here.

[quietvoid]

FFmpeg doesn't support the NAL unit 63. It's just being ignored as expected.
It's the Dolby Vision enhancement layer in profile 7, here embedded in a single video.

[jriker1]

So what I'm doing is OK and even though that message is constantly displaying during encode should ignore it?

[quietvoid]

Probably.

[jriker1]

Would it make more sense to encode without the Dolby Vision content and then inject it with dovi_tool into the hevc after? Would that be more effective?

[quietvoid]

Would it make more sense to encode without the Dolby Vision content and then inject it with dovi_tool into the hevc after? Would that be more effective?

No, it's not more efficient since you're reprocessing the video afterwards when it's not necessary.

If you don't want to see the log spam, remove the EL from the input file.

[jriker1]

OK sounds good. I thought it would inject that additional metadata thru the dovi_tool if I injected it separate but if it's going to cause a re-encode I'd want to skip that. Wondering if nvencc would support this fully. Sent an inquiry that way to check.

[quietvoid]

It's not going to re-encode, there's just no point in injecting after encoding when you can do it while encoding with x265.

[jriker1]

This is weird. Maybe not your problem but thought I'd run it by you as the DolbyVision person. :)

When I encode a video x265 with DolbyVision that doesn't give those NAL unit 63 messages it encodes "fine". When it does display that, I still get video output but it's SUPER small. Like a 80gb source video ends up 4GB. Running it thru FFMetrics if relevant I get:

PSNR: 41.5829
SSIM: 0.9932
VMAF: 93.0939