avformat/mp4: add muxer support for H266/VVC

Add muxer for vvcc byte stream format.
Add AV_CODEC_ID_VVC to ff_mp4_obj_type.
Add AV_CODEC_ID_VVC to ISO Media codec (VvcConfigurationBox vvi1,
vvc1 defined in ISO/IEC 14496-15:2021).
Add VvcConfigurationBox vvcC which extends FullBox type in
ISO/IEC 14496-15:2021.

Tested with:
    ffmpeg -i NovosobornayaSquare_1920x1080.mp4 -c:v libvvenc test.mp4 && ffmpeg -i test.mp4 -f null -
    ffmpeg -i NovosobornayaSquare_1920x1080.mp4 -c:v copy test.mp4     && ffmpeg -i test.mp4 -f md5 -

Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Thomas Siedel <thomas.ff@spin-digital.com>
Co-Authored-By: Nuo Mi <nuomi2021@gmail.com>

7 files changed, 1122 insertions, 4 deletions

diff --git a/libavformat/Makefile b/libavformat/Makefile
index dcc99eeac4..05b9b8a115 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -343,7 +343,7 @@ OBJS-$(CONFIG_MATROSKA_DEMUXER)          += matroskadec.o matroska.o  \
                                             oggparsevorbis.o vorbiscomment.o \
                                             qtpalette.o replaygain.o dovi_isom.o
 OBJS-$(CONFIG_MATROSKA_MUXER)            += matroskaenc.o matroska.o \
-                                            av1.o avc.o hevc.o \
+                                            av1.o avc.o hevc.o vvc.o\
                                             flacenc_header.o avlanguage.o \
                                             vorbiscomment.o wv.o dovi_isom.o
 OBJS-$(CONFIG_MCA_DEMUXER)               += mca.o
@@ -365,7 +365,7 @@ OBJS-$(CONFIG_MODS_DEMUXER)              += mods.o
 OBJS-$(CONFIG_MOFLEX_DEMUXER)            += moflex.o
 OBJS-$(CONFIG_MOV_DEMUXER)               += mov.o mov_chan.o mov_esds.o \
                                             qtpalette.o replaygain.o dovi_isom.o
-OBJS-$(CONFIG_MOV_MUXER)                 += movenc.o av1.o avc.o hevc.o vpcc.o \
+OBJS-$(CONFIG_MOV_MUXER)                 += movenc.o av1.o avc.o hevc.o vvc.o vpcc.o \
                                             movenchint.o mov_chan.o rtp.o \
                                             movenccenc.o movenc_ttml.o rawutils.o \
                                             dovi_isom.o evc.o
@@ -520,7 +520,7 @@ OBJS-$(CONFIG_RTP_MUXER)                 += rtp.o         \
                                             rtpenc_vp8.o  \
                                             rtpenc_vp9.o                \
                                             rtpenc_xiph.o \
-                                            avc.o hevc.o
+                                            avc.o hevc.o vvc.o
 OBJS-$(CONFIG_RTSP_DEMUXER)              += rtsp.o rtspdec.o httpauth.o \
                                             urldecode.o
 OBJS-$(CONFIG_RTSP_MUXER)                += rtsp.o rtspenc.o httpauth.o \
diff --git a/libavformat/isom.c b/libavformat/isom.c
index 6d019881e5..9fbccd4437 100644
--- a/libavformat/isom.c
+++ b/libavformat/isom.c
@@ -36,6 +36,7 @@ const AVCodecTag ff_mp4_obj_type[] = {
     { AV_CODEC_ID_MPEG4       , 0x20 },
     { AV_CODEC_ID_H264        , 0x21 },
     { AV_CODEC_ID_HEVC        , 0x23 },
+    { AV_CODEC_ID_VVC         , 0x33 },
     { AV_CODEC_ID_AAC         , 0x40 },
     { AV_CODEC_ID_MP4ALS      , 0x40 }, /* 14496-3 ALS */
     { AV_CODEC_ID_MPEG2VIDEO  , 0x61 }, /* MPEG-2 Main */
diff --git a/libavformat/isom_tags.c b/libavformat/isom_tags.c
index a575b7c160..058f0f2a59 100644
--- a/libavformat/isom_tags.c
+++ b/libavformat/isom_tags.c
@@ -118,6 +118,9 @@ const AVCodecTag ff_codec_movvideo_tags[] = {
 
     { AV_CODEC_ID_RAWVIDEO, MKTAG('W', 'R', 'A', 'W') },
 
+    { AV_CODEC_ID_VVC,  MKTAG('v', 'v', 'c', '1') },
+    { AV_CODEC_ID_VVC,  MKTAG('v', 'v', 'i', '1') },
+
     { AV_CODEC_ID_HEVC, MKTAG('h', 'e', 'v', '1') }, /* HEVC/H.265 which indicates parameter sets may be in ES */
     { AV_CODEC_ID_HEVC, MKTAG('h', 'v', 'c', '1') }, /* HEVC/H.265 which indicates parameter sets shall not be in ES */
     { AV_CODEC_ID_HEVC, MKTAG('d', 'v', 'h', 'e') }, /* HEVC-based Dolby Vision derived from hev1 */
diff --git a/libavformat/mov.c b/libavformat/mov.c
index 4cffd6c7db..cf931d4594 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -2123,6 +2123,11 @@ static int mov_read_glbl(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     if ((uint64_t)atom.size > (1<<30))
         return AVERROR_INVALIDDATA;
 
+    if (atom.type == MKTAG('v','v','c','C')) {
+        avio_skip(pb, 4);
+        atom.size -= 4;
+    }
+
     if (atom.size >= 10) {
         // Broken files created by legacy versions of libavformat will
         // wrap a whole fiel atom inside of a glbl atom.
@@ -8129,6 +8134,7 @@ static const MOVParseTableEntry mov_default_parse_table[] = {
 { MKTAG('s','g','p','d'), mov_read_sgpd },
 { MKTAG('s','b','g','p'), mov_read_sbgp },
 { MKTAG('h','v','c','C'), mov_read_glbl },
+{ MKTAG('v','v','c','C'), mov_read_glbl },
 { MKTAG('u','u','i','d'), mov_read_uuid },
 { MKTAG('C','i','n', 0x8e), mov_read_targa_y216 },
 { MKTAG('f','r','e','e'), mov_read_free },
diff --git a/libavformat/movenc.c b/libavformat/movenc.c
index 8a27afbc57..b724bd5ebc 100644
--- a/libavformat/movenc.c
+++ b/libavformat/movenc.c
@@ -68,6 +68,7 @@
 #include "ttmlenc.h"
 #include "version.h"
 #include "vpcc.h"
+#include "vvc.h"
 
 static const AVOption options[] = {
     { "brand",    "Override major brand", offsetof(MOVMuxContext, major_brand),   AV_OPT_TYPE_STRING, {.str = NULL}, .flags = AV_OPT_FLAG_ENCODING_PARAM },
@@ -1473,6 +1474,23 @@ static int mov_write_evcc_tag(AVIOContext *pb, MOVTrack *track)
     return update_size(pb, pos);
 }
 
+static int mov_write_vvcc_tag(AVIOContext *pb, MOVTrack *track)
+{
+    int64_t pos = avio_tell(pb);
+
+    avio_wb32(pb, 0);
+    ffio_wfourcc(pb, "vvcC");
+
+    avio_w8  (pb, 0); /* version */
+    avio_wb24(pb, 0); /* flags */
+
+    if (track->tag == MKTAG('v','v','c','1'))
+        ff_isom_write_vvcc(pb, track->vos_data, track->vos_len, 1);
+    else
+        ff_isom_write_vvcc(pb, track->vos_data, track->vos_len, 0);
+    return update_size(pb, pos);
+}
+
 /* also used by all avid codecs (dv, imx, meridien) and their variants */
 static int mov_write_avid_tag(AVIOContext *pb, MOVTrack *track)
 {
@@ -2382,6 +2400,8 @@ static int mov_write_video_tag(AVFormatContext *s, AVIOContext *pb, MOVMuxContex
         avid = 1;
     } else if (track->par->codec_id == AV_CODEC_ID_HEVC)
         mov_write_hvcc_tag(pb, track);
+    else if (track->par->codec_id == AV_CODEC_ID_VVC)
+        mov_write_vvcc_tag(pb, track);
     else if (track->par->codec_id == AV_CODEC_ID_H264 && !TAG_IS_AVCI(track->tag)) {
         mov_write_avcc_tag(pb, track);
         if (track->mode == MODE_IPOD)
@@ -6170,6 +6190,7 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt)
     if ((par->codec_id == AV_CODEC_ID_DNXHD ||
          par->codec_id == AV_CODEC_ID_H264 ||
          par->codec_id == AV_CODEC_ID_HEVC ||
+         par->codec_id == AV_CODEC_ID_VVC ||
          par->codec_id == AV_CODEC_ID_VP9 ||
          par->codec_id == AV_CODEC_ID_EVC ||
          par->codec_id == AV_CODEC_ID_TRUEHD) && !trk->vos_len &&
@@ -6235,6 +6256,18 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt)
                 size = ff_hevc_annexb2mp4(pb, pkt->data, pkt->size, 0, NULL);
             }
         }
+    } else if (par->codec_id == AV_CODEC_ID_VVC && trk->vos_len > 6 &&
+             (AV_RB24(trk->vos_data) == 1 || AV_RB32(trk->vos_data) == 1)) {
+        /* extradata is Annex B, assume the bitstream is too and convert it */
+        if (trk->hint_track >= 0 && trk->hint_track < mov->nb_tracks) {
+            ret = ff_vvc_annexb2mp4_buf(pkt->data, &reformatted_data,
+                                        &size, 0, NULL);
+            if (ret < 0)
+                return ret;
+            avio_write(pb, reformatted_data, size);
+        } else {
+            size = ff_vvc_annexb2mp4(pb, pkt->data, pkt->size, 0, NULL);
+        }
     } else if (par->codec_id == AV_CODEC_ID_AV1) {
         if (trk->hint_track >= 0 && trk->hint_track < mov->nb_tracks) {
             ret = ff_av1_filter_obus_buf(pkt->data, &reformatted_data,
@@ -6281,6 +6314,8 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt)
             } else if(par->codec_id == AV_CODEC_ID_HEVC && par->extradata_size > 21) {
                 int nal_size_length = (par->extradata[21] & 0x3) + 1;
                 ret = ff_mov_cenc_avc_write_nal_units(s, &trk->cenc, nal_size_length, pb, pkt->data, size);
+            } else if(par->codec_id == AV_CODEC_ID_VVC) {
+                ret = AVERROR_PATCHWELCOME;
             } else {
                 ret = ff_mov_cenc_write_packet(&trk->cenc, pb, pkt->data, size);
             }
@@ -7363,7 +7398,8 @@ static int mov_init(AVFormatContext *s)
 
         if (mov->encryption_scheme == MOV_ENC_CENC_AES_CTR) {
             ret = ff_mov_cenc_init(&track->cenc, mov->encryption_key,
-                (track->par->codec_id == AV_CODEC_ID_H264 || track->par->codec_id == AV_CODEC_ID_HEVC),
+                (track->par->codec_id == AV_CODEC_ID_H264 || track->par->codec_id == AV_CODEC_ID_HEVC ||
+                 track->par->codec_id == AV_CODEC_ID_VVC),
                 s->flags & AVFMT_FLAG_BITEXACT);
             if (ret)
                 return ret;
@@ -7832,6 +7868,8 @@ static const AVCodecTag codec_mp4_tags[] = {
     { AV_CODEC_ID_HEVC,            MKTAG('h', 'e', 'v', '1') },
     { AV_CODEC_ID_HEVC,            MKTAG('h', 'v', 'c', '1') },
     { AV_CODEC_ID_HEVC,            MKTAG('d', 'v', 'h', '1') },
+    { AV_CODEC_ID_VVC,             MKTAG('v', 'v', 'c', '1') },
+    { AV_CODEC_ID_VVC,             MKTAG('v', 'v', 'i', '1') },
     { AV_CODEC_ID_EVC,             MKTAG('e', 'v', 'c', '1') },
     { AV_CODEC_ID_MPEG2VIDEO,      MKTAG('m', 'p', '4', 'v') },
     { AV_CODEC_ID_MPEG1VIDEO,      MKTAG('m', 'p', '4', 'v') },
diff --git a/libavformat/vvc.c b/libavformat/vvc.c
new file mode 100644
index 0000000000..14a4c0a2f3
--- /dev/null
+++ b/libavformat/vvc.c
@@ -0,0 +1,971 @@
+/*
+ * H.266/VVC helper functions for muxers
+ *
+ * Copyright (C) 2022, Thomas Siedel
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavcodec/get_bits.h"
+#include "libavcodec/golomb.h"
+#include "libavcodec/vvc.h"
+#include "libavutil/intreadwrite.h"
+#include "avc.h"
+#include "avio.h"
+#include "avio_internal.h"
+#include "vvc.h"
+
+typedef struct VVCCNALUnitArray {
+    uint8_t array_completeness;
+    uint8_t NAL_unit_type;
+    uint16_t num_nalus;
+    uint16_t *nal_unit_length;
+    uint8_t **nal_unit;
+} VVCCNALUnitArray;
+
+typedef struct VVCPTLRecord {
+    uint8_t num_bytes_constraint_info;
+    uint8_t general_profile_idc;
+    uint8_t general_tier_flag;
+    uint8_t general_level_idc;
+    uint8_t ptl_frame_only_constraint_flag;
+    uint8_t ptl_multilayer_enabled_flag;
+    uint8_t general_constraint_info[9];
+    uint8_t ptl_sublayer_level_present_flag[VVC_MAX_SUBLAYERS - 1];
+    uint8_t sublayer_level_idc[VVC_MAX_SUBLAYERS - 1];
+    uint8_t ptl_num_sub_profiles;
+    uint32_t general_sub_profile_idc[VVC_MAX_SUB_PROFILES];
+} VVCPTLRecord;
+
+typedef struct VVCDecoderConfigurationRecord {
+    uint8_t lengthSizeMinusOne;
+    uint8_t ptl_present_flag;
+    uint16_t ols_idx;
+    uint8_t num_sublayers;
+    uint8_t constant_frame_rate;
+    uint8_t chroma_format_idc;
+    uint8_t bit_depth_minus8;
+    VVCPTLRecord ptl;
+    uint16_t max_picture_width;
+    uint16_t max_picture_height;
+    uint16_t avg_frame_rate;
+    uint8_t num_of_arrays;
+    VVCCNALUnitArray *array;
+} VVCDecoderConfigurationRecord;
+
+typedef struct VVCCProfileTierLevel {
+    uint8_t profile_idc;
+    uint8_t tier_flag;
+    uint8_t general_level_idc;
+    uint8_t ptl_frame_only_constraint_flag;
+    uint8_t ptl_multilayer_enabled_flag;
+// general_constraint_info
+    uint8_t gci_present_flag;
+    uint8_t gci_general_constraints[9];
+    uint8_t gci_num_reserved_bits;
+// end general_constraint_info
+    uint8_t ptl_sublayer_level_present_flag[VVC_MAX_SUBLAYERS - 1];
+    uint8_t sublayer_level_idc[VVC_MAX_SUBLAYERS - 1];
+    uint8_t ptl_num_sub_profiles;
+    uint32_t general_sub_profile_idc[VVC_MAX_SUB_PROFILES];
+} VVCCProfileTierLevel;
+
+static void vvcc_update_ptl(VVCDecoderConfigurationRecord *vvcc,
+                            VVCCProfileTierLevel *ptl)
+{
+    /*
+     * The level indication general_level_idc must indicate a level of
+     * capability equal to or greater than the highest level indicated for the
+     * highest tier in all the parameter sets.
+     */
+    if (vvcc->ptl.general_tier_flag < ptl->tier_flag)
+        vvcc->ptl.general_level_idc = ptl->general_level_idc;
+    else
+        vvcc->ptl.general_level_idc =
+            FFMAX(vvcc->ptl.general_level_idc, ptl->general_level_idc);
+
+    /*
+     * The tier indication general_tier_flag must indicate a tier equal to or
+     * greater than the highest tier indicated in all the parameter sets.
+     */
+    vvcc->ptl.general_tier_flag =
+        FFMAX(vvcc->ptl.general_tier_flag, ptl->tier_flag);
+
+    /*
+     * The profile indication general_profile_idc must indicate a profile to
+     * which the stream associated with this configuration record conforms.
+     *
+     * If the sequence parameter sets are marked with different profiles, then
+     * the stream may need examination to determine which profile, if any, the
+     * entire stream conforms to. If the entire stream is not examined, or the
+     * examination reveals that there is no profile to which the entire stream
+     * conforms, then the entire stream must be split into two or more
+     * sub-streams with separate configuration records in which these rules can
+     * be met.
+     *
+     * Note: set the profile to the highest value for the sake of simplicity.
+     */
+    vvcc->ptl.general_profile_idc =
+        FFMAX(vvcc->ptl.general_profile_idc, ptl->profile_idc);
+
+    /*
+     * Each bit in flags may only be set if all
+     * the parameter sets set that bit.
+     */
+    vvcc->ptl.ptl_frame_only_constraint_flag &=
+        ptl->ptl_frame_only_constraint_flag;
+    vvcc->ptl.ptl_multilayer_enabled_flag &= ptl->ptl_multilayer_enabled_flag;
+
+    /*
+     * Constraints Info
+     */
+    if (ptl->gci_present_flag) {
+        vvcc->ptl.num_bytes_constraint_info = 9;
+        memcpy(&vvcc->ptl.general_constraint_info[0],
+               &ptl->gci_general_constraints[0], sizeof(uint8_t) * 9);
+
+    } else {
+        vvcc->ptl.num_bytes_constraint_info = 1;
+        memset(&vvcc->ptl.general_constraint_info[0], 0, sizeof(uint8_t) * 9);
+    }
+
+    /*
+     * Each bit in flags may only be set if one of
+     * the parameter sets set that bit.
+     */
+    memset(vvcc->ptl.ptl_sublayer_level_present_flag, 0,
+           sizeof(uint8_t) * vvcc->num_sublayers - 1);
+    memset(vvcc->ptl.sublayer_level_idc, 0,
+           sizeof(uint8_t) * vvcc->num_sublayers - 1);
+
+    for (int i = vvcc->num_sublayers - 2; i >= 0; i--) {
+        vvcc->ptl.ptl_sublayer_level_present_flag[i] |=
+            ptl->ptl_sublayer_level_present_flag[i];
+        if (vvcc->ptl.ptl_sublayer_level_present_flag[i]) {
+            vvcc->ptl.sublayer_level_idc[i] =
+                FFMAX(vvcc->ptl.sublayer_level_idc[i],
+                      ptl->sublayer_level_idc[i]);
+        } else {
+            if (i == vvcc->num_sublayers - 1) {
+                vvcc->ptl.sublayer_level_idc[i] = vvcc->ptl.general_level_idc;
+            } else {
+                vvcc->ptl.sublayer_level_idc[i] =
+                    vvcc->ptl.sublayer_level_idc[i + 1];
+            }
+        }
+    }
+
+    vvcc->ptl.ptl_num_sub_profiles =
+        FFMAX(vvcc->ptl.ptl_num_sub_profiles, ptl->ptl_num_sub_profiles);
+    if (vvcc->ptl.ptl_num_sub_profiles) {
+        for (int i = 0; i < vvcc->ptl.ptl_num_sub_profiles; i++) {
+            vvcc->ptl.general_sub_profile_idc[i] =
+                ptl->general_sub_profile_idc[i];
+        }
+    }
+}
+
+static void vvcc_parse_ptl(GetBitContext *gb,
+                           VVCDecoderConfigurationRecord *vvcc,
+                           unsigned int profileTierPresentFlag,
+                           unsigned int max_sub_layers_minus1)
+{
+    VVCCProfileTierLevel general_ptl;
+    int j;
+
+    if (profileTierPresentFlag) {
+        general_ptl.profile_idc = get_bits(gb, 7);
+        general_ptl.tier_flag = get_bits1(gb);
+    }
+    general_ptl.general_level_idc = get_bits(gb, 8);
+
+    general_ptl.ptl_frame_only_constraint_flag = get_bits1(gb);
+    general_ptl.ptl_multilayer_enabled_flag = get_bits1(gb);
+    if (profileTierPresentFlag) {       // parse constraint info
+        general_ptl.gci_present_flag = get_bits1(gb);
+        if (general_ptl.gci_present_flag) {
+            for (j = 0; j < 8; j++)
+                general_ptl.gci_general_constraints[j] = get_bits(gb, 8);
+            general_ptl.gci_general_constraints[8] = get_bits(gb, 7);
+
+            general_ptl.gci_num_reserved_bits = get_bits(gb, 8);
+            skip_bits(gb, general_ptl.gci_num_reserved_bits);
+        }
+        while (gb->index % 8 != 0)
+            skip_bits1(gb);
+    }
+
+    for (int i = max_sub_layers_minus1 - 1; i >= 0; i--)
+        general_ptl.ptl_sublayer_level_present_flag[i] = get_bits1(gb);
+
+    while (gb->index % 8 != 0)
+        skip_bits1(gb);
+
+    for (int i = max_sub_layers_minus1 - 1; i >= 0; i--) {
+        if (general_ptl.ptl_sublayer_level_present_flag[i])
+            general_ptl.sublayer_level_idc[i] = get_bits(gb, 8);
+    }
+
+    if (profileTierPresentFlag) {
+        general_ptl.ptl_num_sub_profiles = get_bits(gb, 8);
+        if (general_ptl.ptl_num_sub_profiles) {
+            for (int i = 0; i < general_ptl.ptl_num_sub_profiles; i++)
+                general_ptl.general_sub_profile_idc[i] = get_bits_long(gb, 32);
+        }
+    }
+
+    vvcc_update_ptl(vvcc, &general_ptl);
+}
+
+static int vvcc_parse_vps(GetBitContext *gb,
+                          VVCDecoderConfigurationRecord *vvcc)
+{
+    unsigned int vps_max_layers_minus1;
+    unsigned int vps_max_sublayers_minus1;
+    unsigned int vps_default_ptl_dpb_hrd_max_tid_flag;
+    unsigned int vps_all_independent_layers_flag;
+    unsigned int vps_each_layer_is_an_ols_flag;
+    unsigned int vps_ols_mode_idc;
+
+    unsigned int vps_pt_present_flag[VVC_MAX_PTLS];
+    unsigned int vps_ptl_max_tid[VVC_MAX_PTLS];
+    unsigned int vps_num_ptls_minus1 = 0;
+
+    /*
+     * vps_video_parameter_set_id u(4)
+     */
+    skip_bits(gb, 4);
+
+    vps_max_layers_minus1 = get_bits(gb, 6);
+    vps_max_sublayers_minus1 = get_bits(gb, 3);
+
+    /*
+     * numTemporalLayers greater than 1 indicates that the stream to which this
+     * configuration record applies is temporally scalable and the contained
+     * number of temporal layers (also referred to as temporal sub-layer or
+     * sub-layer in ISO/IEC 23008-2) is equal to numTemporalLayers. Value 1
+     * indicates that the stream is not temporally scalable. Value 0 indicates
+     * that it is unknown whether the stream is temporally scalable.
+     */
+    vvcc->num_sublayers = FFMAX(vvcc->num_sublayers,
+                                vps_max_sublayers_minus1 + 1);
+
+    if (vps_max_layers_minus1 > 0 && vps_max_sublayers_minus1 > 0)
+        vps_default_ptl_dpb_hrd_max_tid_flag = get_bits1(gb);
+    if (vps_max_layers_minus1 > 0)
+        vps_all_independent_layers_flag = get_bits1(gb);
+    else
+        vps_all_independent_layers_flag = 1;
+
+    for (int i = 0; i <= vps_max_layers_minus1; i++) {
+        skip_bits(gb, 6);    //vps_layer_id[i]
+        if (i > 0 && !vps_all_independent_layers_flag) {
+            if (get_bits1(gb)) {    // vps_independent_layer_flag[i]
+                unsigned int vps_max_tid_ref_present_flag = get_bits1(gb);
+                for (int j = 0; j < i; j++) {
+                    if (vps_max_tid_ref_present_flag && get_bits1(gb))  // vps_direct_ref_layer_flag[i][j]
+                        skip_bits(gb, 3);                               // vps_max_tid_il_ref_pics_plus1
+                }
+            }
+        }
+    }
+
+    if (vps_max_layers_minus1 > 0) {
+        if (vps_all_independent_layers_flag)
+            vps_each_layer_is_an_ols_flag = get_bits1(gb);
+        else
+            vps_each_layer_is_an_ols_flag = 0;
+        if (!vps_each_layer_is_an_ols_flag) {
+            if (!vps_all_independent_layers_flag)
+                vps_ols_mode_idc = get_bits(gb, 2);
+            else
+                vps_ols_mode_idc = 2;
+            if (vps_ols_mode_idc == 2) {
+                unsigned int vps_num_output_layer_sets_minus2 = get_bits(gb, 8);
+                for (int i = 1; i <= vps_num_output_layer_sets_minus2 + 1; i++) {
+                    for (int j = 0; j <= vps_max_layers_minus1; j++) {
+                        skip_bits1(gb); // vps_ols_output_layer_flag[i][j]
+                    }
+                }
+            }
+        }
+        vps_num_ptls_minus1 = get_bits(gb, 8);
+    } else {
+        vps_each_layer_is_an_ols_flag = 0;
+    }
+
+    for (int i = 0; i <= vps_num_ptls_minus1; i++) {
+        if (i > 0)
+            vps_pt_present_flag[i] = get_bits1(gb);
+        else
+            vps_pt_present_flag[i] = 1;
+
+        if (!vps_default_ptl_dpb_hrd_max_tid_flag)
+            vps_ptl_max_tid[i] = get_bits(gb, 3);
+        else
+            vps_ptl_max_tid[i] = vps_max_sublayers_minus1;
+    }
+
+    while (gb->index % 8 != 0)
+        skip_bits1(gb);
+
+    for (int i = 0; i <= vps_num_ptls_minus1; i++)
+        vvcc_parse_ptl(gb, vvcc, vps_pt_present_flag[i], vps_ptl_max_tid[i]);
+
+    /* nothing useful for vvcc past this point */
+    return 0;
+}
+
+static int vvcc_parse_sps(GetBitContext *gb,
+                          VVCDecoderConfigurationRecord *vvcc)
+{
+    unsigned int sps_max_sublayers_minus1, sps_log2_ctu_size_minus5;
+    unsigned int sps_subpic_same_size_flag, sps_pic_height_max_in_luma_samples,
+        sps_pic_width_max_in_luma_samples;
+    unsigned int sps_independent_subpics_flag;
+
+    skip_bits(gb, 8);  // sps_seq_parameter_set_id && sps_video_parameter_set_id
+    sps_max_sublayers_minus1 = get_bits(gb, 3);
+
+    /*
+     * numTemporalLayers greater than 1 indicates that the stream to which this
+     * configuration record applies is temporally scalable and the contained
+     * number of temporal layers (also referred to as temporal sub-layer or
+     * sub-layer in ISO/IEC 23008-2) is equal to numTemporalLayers. Value 1
+     * indicates that the stream is not temporally scalable. Value 0 indicates
+     * that it is unknown whether the stream is temporally scalable.
+     */
+    vvcc->num_sublayers = FFMAX(vvcc->num_sublayers,
+                                sps_max_sublayers_minus1 + 1);
+
+    vvcc->chroma_format_idc = get_bits(gb, 2);
+    sps_log2_ctu_size_minus5 = get_bits(gb, 2);
+
+    if (get_bits1(gb))          // sps_ptl_dpb_hrd_params_present_flag
+        vvcc_parse_ptl(gb, vvcc, 1, sps_max_sublayers_minus1);
+
+    skip_bits1(gb);             // sps_gdr_enabled_flag
+    if (get_bits(gb, 1))        // sps_ref_pic_resampling_enabled_flag
+        skip_bits1(gb);         // sps_res_change_in_clvs_allowed_flag
+
+    sps_pic_width_max_in_luma_samples = get_ue_golomb_long(gb);
+    vvcc->max_picture_width =
+        FFMAX(vvcc->max_picture_width, sps_pic_width_max_in_luma_samples);
+    sps_pic_height_max_in_luma_samples = get_ue_golomb_long(gb);
+    vvcc->max_picture_height =
+        FFMAX(vvcc->max_picture_height, sps_pic_height_max_in_luma_samples);
+
+    if (get_bits1(gb)) {
+        get_ue_golomb_long(gb); // sps_conf_win_left_offset
+        get_ue_golomb_long(gb); // sps_conf_win_right_offset
+        get_ue_golomb_long(gb); // sps_conf_win_top_offset
+        get_ue_golomb_long(gb); // sps_conf_win_bottom_offset
+    }
+
+    if (get_bits1(gb)) {        // sps_subpic_info_present_flag
+        const unsigned int sps_num_subpics_minus1 = get_ue_golomb_long(gb);
+        const int ctb_log2_size_y = sps_log2_ctu_size_minus5 + 5;
+        const int ctb_size_y      = 1 << ctb_log2_size_y;
+        const int tmp_width_val   = AV_CEIL_RSHIFT(sps_pic_width_max_in_luma_samples,  ctb_log2_size_y);
+        const int tmp_height_val  = AV_CEIL_RSHIFT(sps_pic_height_max_in_luma_samples, ctb_log2_size_y);
+        const int wlen            = av_ceil_log2(tmp_width_val);
+        const int hlen            = av_ceil_log2(tmp_height_val);
+        if (sps_num_subpics_minus1 > 0) {       // sps_num_subpics_minus1
+            sps_independent_subpics_flag = get_bits1(gb);
+            sps_subpic_same_size_flag = get_bits1(gb);
+        }
+        for (int i = 0; sps_num_subpics_minus1 > 0 && i <= sps_num_subpics_minus1; i++) {
+            if (!sps_subpic_same_size_flag || i == 0) {
+                if (i > 0 && sps_pic_width_max_in_luma_samples > ctb_size_y)
+                    skip_bits(gb, wlen);
+                if (i > 0 && sps_pic_height_max_in_luma_samples > ctb_size_y)
+                    skip_bits(gb, hlen);
+                if (i < sps_num_subpics_minus1 && sps_pic_width_max_in_luma_samples > ctb_size_y)
+                    skip_bits(gb, wlen);
+                if (i < sps_num_subpics_minus1 && sps_pic_height_max_in_luma_samples > ctb_size_y)
+                    skip_bits(gb, hlen);
+            }
+            if (!sps_independent_subpics_flag) {
+                skip_bits(gb, 2);       // sps_subpic_treated_as_pic_flag && sps_loop_filter_across_subpic_enabled_flag
+            }
+        }
+        get_ue_golomb_long(gb); // sps_subpic_id_len_minus1
+        if (get_bits1(gb)) {    // sps_subpic_id_mapping_explicitly_signalled_flag
+            if (get_bits1(gb))  // sps_subpic_id_mapping_present_flag
+                for (int i = 0; i <= sps_num_subpics_minus1; i++) {
+                    skip_bits1(gb);     // sps_subpic_id[i]
+                }
+        }
+    }
+    vvcc->bit_depth_minus8 = get_ue_golomb_long(gb);
+
+    /* nothing useful for vvcc past this point */
+    return 0;
+}
+
+static int vvcc_parse_pps(GetBitContext *gb,
+                          VVCDecoderConfigurationRecord *vvcc)
+{
+
+    // Nothing of importance to parse in PPS
+    /* nothing useful for vvcc past this point */
+    return 0;
+}
+
+static void nal_unit_parse_header(GetBitContext *gb, uint8_t *nal_type)
+{
+    /*
+     * forbidden_zero_bit    u(1)
+     * nuh_reserved_zero_bit u(1)
+     * nuh_layer_id          u(6)
+     */
+    skip_bits(gb, 8);
+    *nal_type = get_bits(gb, 5);
+
+    /*
+     * nuh_temporal_id_plus1 u(3)
+     */
+    skip_bits(gb, 3);
+}
+
+static int vvcc_array_add_nal_unit(uint8_t *nal_buf, uint32_t nal_size,
+                                   uint8_t nal_type, int ps_array_completeness,
+                                   VVCDecoderConfigurationRecord *vvcc)
+{
+    int ret;
+    uint8_t index;
+    uint16_t num_nalus;
+    VVCCNALUnitArray *array;
+
+    for (index = 0; index < vvcc->num_of_arrays; index++)
+        if (vvcc->array[index].NAL_unit_type == nal_type)
+            break;
+
+    if (index >= vvcc->num_of_arrays) {
+        uint8_t i;
+
+        ret =
+            av_reallocp_array(&vvcc->array, index + 1,
+                              sizeof(VVCCNALUnitArray));
+        if (ret < 0)
+            return ret;
+
+        for (i = vvcc->num_of_arrays; i <= index; i++)
+            memset(&vvcc->array[i], 0, sizeof(VVCCNALUnitArray));
+        vvcc->num_of_arrays = index + 1;
+    }
+
+    array = &vvcc->array[index];
+    num_nalus = array->num_nalus;
+
+    ret = av_reallocp_array(&array->nal_unit, num_nalus + 1, sizeof(uint8_t *));
+    if (ret < 0)
+        return ret;
+
+    ret =
+        av_reallocp_array(&array->nal_unit_length, num_nalus + 1,
+                          sizeof(uint16_t));
+    if (ret < 0)
+        return ret;
+
+    array->nal_unit[num_nalus] = nal_buf;
+    array->nal_unit_length[num_nalus] = nal_size;
+    array->NAL_unit_type = nal_type;
+    array->num_nalus++;
+
+    /*
+    * When the sample entry name is 'vvc1', the following applies:
+    * • The value of array_completeness shall be equal to 1 for arrays of SPS,
+    *   and PPS NAL units.
+    * • If a VVC bitstream includes DCI NAL unit(s), the value of
+    *   array_completeness shall be equal to 1 for the array of DCI units.
+    *   Otherwise, NAL_unit_type shall not indicate DCI NAL units.
+    * • If a VVC bitstream includes VPS NAL unit(s), the value of
+    *   array_completeness shall be equal to 1 for the array of VPS NAL units.
+    *   Otherwise, NAL_unit_type shall not indicate VPS NAL units.
+    * When the value of array_completeness is equal to 1 for an array of a
+    * particular NAL_unit_type value, NAL units of that NAL_unit_type value
+    * cannot be updated without causing a different sample entry to be used.
+    * When the sample entry name is 'vvi1', the value of array_completeness
+    * of at least one of the following arrays shall be equal to 0:
+      • The array of DCI NAL units, if present.
+      • The array of VPS NAL units, if present.
+      • The array of SPS NAL units
+      • The array of PPS NAL units.
+    */
+    if (nal_type == VVC_VPS_NUT || nal_type == VVC_SPS_NUT ||
+        nal_type == VVC_PPS_NUT || nal_type == VVC_DCI_NUT )
+        array->array_completeness = ps_array_completeness;
+
+    return 0;
+}
+
+static int vvcc_add_nal_unit(uint8_t *nal_buf, uint32_t nal_size,
+                             int ps_array_completeness,
+                             VVCDecoderConfigurationRecord *vvcc)
+{
+    int ret = 0;
+    GetBitContext gbc;
+    uint8_t nal_type;
+    uint8_t *rbsp_buf;
+    uint32_t rbsp_size;
+
+    rbsp_buf = ff_nal_unit_extract_rbsp(nal_buf, nal_size, &rbsp_size, 2);
+    if (!rbsp_buf) {
+        ret = AVERROR(ENOMEM);
+        goto end;
+    }
+
+    ret = init_get_bits8(&gbc, rbsp_buf, rbsp_size);
+    if (ret < 0)
+        goto end;
+
+    nal_unit_parse_header(&gbc, &nal_type);
+
+    /*
+     * Note: only 'declarative' SEI messages are allowed in
+     * vvcc. Perhaps the SEI playload type should be checked
+     * and non-declarative SEI messages discarded?
+     */
+    switch (nal_type) {
+    case VVC_OPI_NUT:
+    case VVC_VPS_NUT:
+    case VVC_SPS_NUT:
+    case VVC_PPS_NUT:
+    case VVC_PREFIX_SEI_NUT:
+    case VVC_SUFFIX_SEI_NUT:
+        ret = vvcc_array_add_nal_unit(nal_buf, nal_size, nal_type,
+                                      ps_array_completeness, vvcc);
+        if (ret < 0)
+            goto end;
+        else if (nal_type == VVC_VPS_NUT)
+            ret = vvcc_parse_vps(&gbc, vvcc);
+        else if (nal_type == VVC_SPS_NUT)
+            ret = vvcc_parse_sps(&gbc, vvcc);
+        else if (nal_type == VVC_PPS_NUT)
+            ret = vvcc_parse_pps(&gbc, vvcc);
+        else if (nal_type == VVC_OPI_NUT) {
+            // not yet supported
+        }
+        if (ret < 0)
+            goto end;
+        break;
+    default:
+        ret = AVERROR_INVALIDDATA;
+        goto end;
+    }
+
+  end:
+    av_free(rbsp_buf);
+    return ret;
+}
+
+static void vvcc_init(VVCDecoderConfigurationRecord *vvcc)
+{
+    memset(vvcc, 0, sizeof(VVCDecoderConfigurationRecord));
+    vvcc->lengthSizeMinusOne = 3;       // 4 bytes
+
+    vvcc->ptl.num_bytes_constraint_info = 1;
+
+    vvcc->ptl_present_flag = 1;
+}
+
+static void vvcc_close(VVCDecoderConfigurationRecord *vvcc)
+{
+    uint8_t i;
+
+    for (i = 0; i < vvcc->num_of_arrays; i++) {
+        vvcc->array[i].num_nalus = 0;
+        av_freep(&vvcc->array[i].nal_unit);
+        av_freep(&vvcc->array[i].nal_unit_length);
+    }
+
+    vvcc->num_of_arrays = 0;
+    av_freep(&vvcc->array);
+}
+
+static int vvcc_write(AVIOContext *pb, VVCDecoderConfigurationRecord *vvcc)
+{
+    uint8_t i;
+    uint16_t j, vps_count = 0, sps_count = 0, pps_count = 0;
+    unsigned char *buf = NULL;
+    /*
+     * It's unclear how to properly compute these fields, so
+     * let's always set them to values meaning 'unspecified'.
+     */
+    vvcc->avg_frame_rate = 0;
+    vvcc->constant_frame_rate = 1;
+
+    av_log(NULL, AV_LOG_TRACE,
+           "lengthSizeMinusOne:                  %" PRIu8 "\n",
+           vvcc->lengthSizeMinusOne);
+    av_log(NULL, AV_LOG_TRACE,
+           "ptl_present_flag:                    %" PRIu8 "\n",
+           vvcc->ptl_present_flag);
+    av_log(NULL, AV_LOG_TRACE,
+           "ols_idx:                             %" PRIu16 "\n", vvcc->ols_idx);
+    av_log(NULL, AV_LOG_TRACE,
+           "num_sublayers:                       %" PRIu8 "\n",
+           vvcc->num_sublayers);
+    av_log(NULL, AV_LOG_TRACE,
+           "constant_frame_rate:                 %" PRIu8 "\n",
+           vvcc->constant_frame_rate);
+    av_log(NULL, AV_LOG_TRACE,
+           "chroma_format_idc:                   %" PRIu8 "\n",
+           vvcc->chroma_format_idc);
+
+    av_log(NULL, AV_LOG_TRACE,
+           "bit_depth_minus8:                    %" PRIu8 "\n",
+           vvcc->bit_depth_minus8);
+    av_log(NULL, AV_LOG_TRACE,
+           "num_bytes_constraint_info:           %" PRIu8 "\n",
+           vvcc->ptl.num_bytes_constraint_info);
+    av_log(NULL, AV_LOG_TRACE,
+           "general_profile_idc:                 %" PRIu8 "\n",
+           vvcc->ptl.general_profile_idc);
+    av_log(NULL, AV_LOG_TRACE,
+           "general_tier_flag:                   %" PRIu8 "\n",
+           vvcc->ptl.general_tier_flag);
+    av_log(NULL, AV_LOG_TRACE,
+           "general_level_idc:                   %" PRIu8 "\n",
+           vvcc->ptl.general_level_idc);
+    av_log(NULL, AV_LOG_TRACE,
+           "ptl_frame_only_constraint_flag:      %" PRIu8 "\n",
+           vvcc->ptl.ptl_frame_only_constraint_flag);
+    av_log(NULL, AV_LOG_TRACE,
+           "ptl_multilayer_enabled_flag:         %" PRIu8 "\n",
+           vvcc->ptl.ptl_multilayer_enabled_flag);
+    for (i = 0; i < vvcc->ptl.num_bytes_constraint_info; i++) {
+        av_log(NULL, AV_LOG_TRACE,
+               "general_constraint_info[%d]:          %" PRIu8 "\n", i,
+               vvcc->ptl.general_constraint_info[i]);
+    }
+
+    for (i = 0; i < vvcc->num_sublayers - 1; i++) {
+        av_log(NULL, AV_LOG_TRACE,
+               "ptl_sublayer_level_present_flag[%" PRIu8 "]:  %" PRIu8 "\n", i,
+               vvcc->ptl.ptl_sublayer_level_present_flag[i]);
+        av_log(NULL, AV_LOG_TRACE,
+               "sublayer_level_idc[%" PRIu8 "]: %" PRIu8 "\n", i,
+               vvcc->ptl.sublayer_level_idc[i]);
+    }
+
+    av_log(NULL, AV_LOG_TRACE,
+           "num_sub_profiles:                    %" PRIu8 "\n",
+           vvcc->ptl.ptl_num_sub_profiles);
+
+    for (i = 0; i < vvcc->ptl.ptl_num_sub_profiles; i++) {
+        av_log(NULL, AV_LOG_TRACE,
+               "general_sub_profile_idc[%" PRIu8 "]:         %" PRIx32 "\n", i,
+               vvcc->ptl.general_sub_profile_idc[i]);
+    }
+
+    av_log(NULL, AV_LOG_TRACE,
+           "max_picture_width:                   %" PRIu16 "\n",
+           vvcc->max_picture_width);
+    av_log(NULL, AV_LOG_TRACE,
+           "max_picture_height:                  %" PRIu16 "\n",
+           vvcc->max_picture_height);
+    av_log(NULL, AV_LOG_TRACE,
+           "avg_frame_rate:                      %" PRIu16 "\n",
+           vvcc->avg_frame_rate);
+
+    av_log(NULL, AV_LOG_TRACE,
+           "num_of_arrays:                       %" PRIu8 "\n",
+           vvcc->num_of_arrays);
+    for (i = 0; i < vvcc->num_of_arrays; i++) {
+        av_log(NULL, AV_LOG_TRACE,
+               "array_completeness[%" PRIu8 "]:               %" PRIu8 "\n", i,
+               vvcc->array[i].array_completeness);
+        av_log(NULL, AV_LOG_TRACE,
+               "NAL_unit_type[%" PRIu8 "]:                    %" PRIu8 "\n", i,
+               vvcc->array[i].NAL_unit_type);
+        av_log(NULL, AV_LOG_TRACE,
+               "num_nalus[%" PRIu8 "]:                        %" PRIu16 "\n", i,
+               vvcc->array[i].num_nalus);
+        for (j = 0; j < vvcc->array[i].num_nalus; j++)
+            av_log(NULL, AV_LOG_TRACE,
+                   "nal_unit_length[%" PRIu8 "][%" PRIu16 "]:               %"
+                   PRIu16 "\n", i, j, vvcc->array[i].nal_unit_length[j]);
+    }
+
+    /*
+     * We need at least one of each: VPS and SPS.
+     */
+    for (i = 0; i < vvcc->num_of_arrays; i++)
+        switch (vvcc->array[i].NAL_unit_type) {
+        case VVC_VPS_NUT:
+            vps_count += vvcc->array[i].num_nalus;
+            break;
+        case VVC_SPS_NUT:
+            sps_count += vvcc->array[i].num_nalus;
+            break;
+        case VVC_PPS_NUT:
+            pps_count += vvcc->array[i].num_nalus;
+            break;
+        default:
+            break;
+        }
+
+    if (vps_count > VVC_MAX_VPS_COUNT)
+        return AVERROR_INVALIDDATA;
+    if (!sps_count || sps_count > VVC_MAX_SPS_COUNT)
+        return AVERROR_INVALIDDATA;
+    if (!pps_count || pps_count > VVC_MAX_PPS_COUNT)
+        return AVERROR_INVALIDDATA;
+
+    /* bit(5) reserved = ‘11111’b;
+       unsigned int (2) LengthSizeMinusOne
+       unsigned int (1) ptl_present_flag */
+    avio_w8(pb, vvcc->lengthSizeMinusOne << 1 | vvcc->ptl_present_flag | 0xf8);
+
+    if (vvcc->ptl_present_flag) {
+        /*
+         * unsigned int(9) ols_idx;
+         * unsigned int(3) num_sublayers;
+         * unsigned int(2) constant_frame_rate;
+         * unsigned int(2) chroma_format_idc;     */
+        avio_wb16(pb,
+                  vvcc->ols_idx << 7 | vvcc->num_sublayers << 4 | vvcc->
+                  constant_frame_rate << 2 | vvcc->chroma_format_idc);
+
+        /* unsigned int(3) bit_depth_minus8;
+           bit(5) reserved = ‘11111’b; */
+        avio_w8(pb, vvcc->bit_depth_minus8 << 5 | 0x1f);
+
+        //VVCPTLRecord
+
+        /* bit(2) reserved = ‘00’b;
+           unsigned int (6) num_bytes_constraint_info */
+        avio_w8(pb, vvcc->ptl.num_bytes_constraint_info & 0x3f);
+
+        /* unsigned int (7) general_profile_idc
+           unsigned int (1) general_tier_flag */
+        avio_w8(pb,
+                vvcc->ptl.general_profile_idc << 1 | vvcc->ptl.general_tier_flag);
+
+        /* unsigned int (8) general_level_idc */
+        avio_w8(pb, vvcc->ptl.general_level_idc);
+
+        /*
+         * unsigned int (1) ptl_frame_only_constraint_flag
+         * unsigned int (1) ptl_multilayer_enabled_flag
+         * unsigned int (8*num_bytes_constraint_info -2) general_constraint_info */
+        buf =
+            (unsigned char *) malloc(sizeof(unsigned char) *
+                                     vvcc->ptl.num_bytes_constraint_info);
+        *buf = vvcc->ptl.ptl_frame_only_constraint_flag << vvcc->ptl.
+            num_bytes_constraint_info * 8 - 1 | vvcc->ptl.
+            ptl_multilayer_enabled_flag << vvcc->ptl.num_bytes_constraint_info *
+            8 - 2 | *vvcc->ptl.general_constraint_info >> 2;
+        avio_write(pb, buf, vvcc->ptl.num_bytes_constraint_info);
+        free(buf);
+
+        if (vvcc->num_sublayers > 1) {
+            uint8_t ptl_sublayer_level_present_flags = 0;
+            for (int i = vvcc->num_sublayers - 2; i >= 0; i--) {
+                ptl_sublayer_level_present_flags =
+                    (ptl_sublayer_level_present_flags << 1 | vvcc->ptl.
+                     ptl_sublayer_level_present_flag[i]);
+            }
+            avio_w8(pb, ptl_sublayer_level_present_flags);
+        }
+
+        for (int i = vvcc->num_sublayers - 2; i >= 0; i--) {
+            if (vvcc->ptl.ptl_sublayer_level_present_flag[i])
+                avio_w8(pb, vvcc->ptl.sublayer_level_idc[i]);
+        }
+
+        /* unsigned int(8) num_sub_profiles; */
+        avio_w8(pb, vvcc->ptl.ptl_num_sub_profiles);
+
+        for (int j = 0; j < vvcc->ptl.ptl_num_sub_profiles; j++) {
+            /* unsigned int(32) general_sub_profile_idc[j]; */
+            avio_wb32(pb, vvcc->ptl.general_sub_profile_idc[j]);
+        }
+
+        //End of VvcPTLRecord
+
+        /*
+         * unsigned int(16) max_picture_width;*/
+        avio_wb16(pb, vvcc->max_picture_width);
+
+        /*
+         * unsigned int(16) max_picture_height;*/
+        avio_wb16(pb, vvcc->max_picture_height);
+
+        /*
+         * unsigned int(16) avg_frame_rate; */
+        avio_wb16(pb, vvcc->avg_frame_rate);
+    }
+
+    /* unsigned int(8) num_of_arrays; */
+    avio_w8(pb, vvcc->num_of_arrays);
+
+    for (i = 0; i < vvcc->num_of_arrays; i++) {
+        /*
+         * bit(1) array_completeness;
+         * unsigned int(2) reserved = 0;
+         * unsigned int(5) NAL_unit_type;
+         */
+        avio_w8(pb, vvcc->array[i].array_completeness << 7 |
+                vvcc->array[i].NAL_unit_type & 0x1f);
+        /* unsigned int(16) num_nalus; */
+        if (vvcc->array[i].NAL_unit_type != VVC_DCI_NUT &&
+            vvcc->array[i].NAL_unit_type != VVC_OPI_NUT)
+            avio_wb16(pb, vvcc->array[i].num_nalus);
+        for (j = 0; j < vvcc->array[i].num_nalus; j++) {
+            /* unsigned int(16) nal_unit_length; */
+            avio_wb16(pb, vvcc->array[i].nal_unit_length[j]);
+
+            /* bit(8*nal_unit_length) nal_unit; */
+            avio_write(pb, vvcc->array[i].nal_unit[j],
+                       vvcc->array[i].nal_unit_length[j]);
+        }
+    }
+
+    return 0;
+}
+
+int ff_vvc_annexb2mp4(AVIOContext *pb, const uint8_t *buf_in,
+                      int size, int filter_ps, int *ps_count)
+{
+    int num_ps = 0, ret = 0;
+    uint8_t *buf, *end, *start = NULL;
+
+    if (!filter_ps) {
+        ret = ff_avc_parse_nal_units(pb, buf_in, size);
+        goto end;
+    }
+
+    ret = ff_avc_parse_nal_units_buf(buf_in, &start, &size);
+    if (ret < 0)
+        goto end;
+
+    ret = 0;
+    buf = start;
+    end = start + size;
+
+    while (end - buf > 4) {
+        uint32_t len = FFMIN(AV_RB32(buf), end - buf - 4);
+        uint8_t type = (buf[5] >> 3);
+
+        buf += 4;
+
+        switch (type) {
+        case VVC_VPS_NUT:
+        case VVC_SPS_NUT:
+        case VVC_PPS_NUT:
+            num_ps++;
+            break;
+        default:
+            ret += 4 + len;
+            avio_wb32(pb, len);
+            avio_write(pb, buf, len);
+            break;
+        }
+
+        buf += len;
+    }
+
+  end:
+    av_free(start);
+    if (ps_count)
+        *ps_count = num_ps;
+    return ret;
+}
+
+int ff_vvc_annexb2mp4_buf(const uint8_t *buf_in, uint8_t **buf_out,
+                          int *size, int filter_ps, int *ps_count)
+{
+    AVIOContext *pb;
+    int ret;
+
+    ret = avio_open_dyn_buf(&pb);
+    if (ret < 0)
+        return ret;
+
+    ret = ff_vvc_annexb2mp4(pb, buf_in, *size, filter_ps, ps_count);
+    if (ret < 0) {
+        ffio_free_dyn_buf(&pb);
+        return ret;
+    }
+
+    *size = avio_close_dyn_buf(pb, buf_out);
+
+    return 0;
+}
+
+int ff_isom_write_vvcc(AVIOContext *pb, const uint8_t *data,
+                       int size, int ps_array_completeness)
+{
+    VVCDecoderConfigurationRecord vvcc;
+    uint8_t *buf, *end, *start;
+    int ret;
+
+    if (size < 6) {
+        /* We can't write a valid vvcc from the provided data */
+        return AVERROR_INVALIDDATA;
+    } else if ((*data & 0xf8) == 0xf8) {
+        /* Data is already vvcc-formatted */
+        avio_write(pb, data, size);
+        return 0;
+    } else if (!(AV_RB24(data) == 1 || AV_RB32(data) == 1)) {
+        /* Not a valid Annex B start code prefix */
+        return AVERROR_INVALIDDATA;
+    }
+
+    ret = ff_avc_parse_nal_units_buf(data, &start, &size);
+    if (ret < 0)
+        return ret;
+
+    vvcc_init(&vvcc);
+
+    buf = start;
+    end = start + size;
+
+    while (end - buf > 4) {
+        uint32_t len = FFMIN(AV_RB32(buf), end - buf - 4);
+        uint8_t type = (buf[5] >> 3);
+
+        buf += 4;
+
+        switch (type) {
+        case VVC_OPI_NUT:
+        case VVC_VPS_NUT:
+        case VVC_SPS_NUT:
+        case VVC_PPS_NUT:
+        case VVC_PREFIX_SEI_NUT:
+        case VVC_SUFFIX_SEI_NUT:
+            ret = vvcc_add_nal_unit(buf, len, ps_array_completeness, &vvcc);
+            if (ret < 0)
+                goto end;
+            break;
+        default:
+            break;
+        }
+
+        buf += len;
+    }
+
+    ret = vvcc_write(pb, &vvcc);
+
+  end:
+    vvcc_close(&vvcc);
+    av_free(start);
+    return ret;
+}
diff --git a/libavformat/vvc.h b/libavformat/vvc.h
new file mode 100644
index 0000000000..11c700540f
--- /dev/null
+++ b/libavformat/vvc.h
@@ -0,0 +1,99 @@
+/*
+ * H.266 / VVC helper functions for muxers
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * internal header for H.266/VVC (de)muxer utilities
+ */
+
+#ifndef AVFORMAT_VVC_H
+#define AVFORMAT_VVC_H
+
+#include <stdint.h>
+#include "avio.h"
+
+/**
+ * Writes Annex B formatted H.266/VVC NAL units to the provided AVIOContext.
+ *
+ * The NAL units are converted to an MP4-compatible format (start code prefixes
+ * are replaced by 4-byte size fields, as per ISO/IEC 14496-15).
+ *
+ * If filter_ps is non-zero, any VVC parameter sets found in the input will be
+ * discarded, and *ps_count will be set to the number of discarded PS NAL units.
+ *
+ * @param pb address of the AVIOContext where the data shall be written
+ * @param buf_in address of the buffer holding the input data
+ * @param size size (in bytes) of the input buffer
+ * @param filter_ps whether to write parameter set NAL units to the output (0)
+ *        or to discard them (non-zero)
+ * @param ps_count address of the variable where the number of discarded
+ *        parameter set NAL units shall be written, may be NULL
+ * @return the amount (in bytes) of data written in case of success, a negative
+ *         value corresponding to an AVERROR code in case of failure
+ */
+int ff_vvc_annexb2mp4(AVIOContext *pb, const uint8_t *buf_in,
+                      int size, int filter_ps, int *ps_count);
+
+/**
+ * Writes Annex B formatted H.266/VVC NAL units to a data buffer.
+ *
+ * The NAL units are converted to an MP4-compatible format (start code prefixes
+ * are replaced by 4-byte size fields, as per ISO/IEC 14496-15).
+ *
+ * If filter_ps is non-zero, any VVC parameter sets found in the input will be
+ * discarded, and *ps_count will be set to the number of discarded PS NAL units.
+ *
+ * On success, *size holds the size (in bytes) of the output data buffer.
+ *
+ * @param buf_in address of the buffer holding the input data
+ * @param size address of the variable holding the size (in bytes) of the input
+ *        buffer (on input) and of the output buffer (on success)
+ * @param buf_out on success, address of the variable holding the address of
+ *        the output buffer
+ * @param filter_ps whether to write parameter set NAL units to the output (0)
+ *        or to discard them (non-zero)
+ * @param ps_count address of the variable where the number of discarded
+ *        parameter set NAL units shall be written, may be NULL
+ * @return 0 in case of success, a negative value corresponding to an AVERROR
+ *         code in case of failure
+ * @note *buf_out will be treated as uninitialized on input and won't be freed.
+ */
+int ff_vvc_annexb2mp4_buf(const uint8_t *buf_in, uint8_t **buf_out,
+                          int *size, int filter_ps, int *ps_count);
+
+/**
+ * Writes H.266/VVC extradata (parameter sets, declarative SEI NAL units) to
+ * the provided AVIOContext.
+ *
+ * If the extradata is Annex B format, it gets converted to vvcC format before
+ * writing.
+ *
+ * @param pb address of the AVIOContext where the vvcC shall be written
+ * @param data address of the buffer holding the data needed to write the vvcC
+ * @param size size (in bytes) of the data buffer
+ * @param ps_array_completeness whether all parameter sets are in the vvcC (1)
+ *        or there may be additional parameter sets in the bitstream (0)
+ * @return >=0 in case of success, a negative value corresponding to an AVERROR
+ *         code in case of failure
+ */
+int ff_isom_write_vvcc(AVIOContext *pb, const uint8_t *data,
+                       int size, int ps_array_completeness);
+
+#endif /* AVFORMAT_VVC_H */