[FFmpeg-devel] [PATCH 3/3] avformat/movenc: Add support for AVIF muxing

Andreas Rheinhardt andreas.rheinhardt at outlook.com
Thu Mar 10 18:01:02 EET 2022


Vignesh Venkatasubramanian:
> Add an AVIF muxer by re-using the existing the mov/mp4 muxer.
> 
> AVIF Specifiation: https://aomediacodec.github.io/av1-avif
> 
> Sample usage for still image:
> ffmpeg -i image.png -c:v libaom-av1 -avif-image 1 image.avif
> 
> Sample usage for animated AVIF image:
> ffmpeg -i video.mp4 animated.avif
> 
> We can re-use any of the AV1 encoding options that will make
> sense for image encoding (like bitrate, tiles, encoding speed,
> etc).
> 
> The files generated by this muxer has been verified to be valid
> AVIF files by the following:
> 1) Displays on Chrome (both still and animated images).
> 2) Displays on Firefox (only still images, firefox does not support
>    animated AVIF yet).
> 3) Verfied to be valid by Compliance Warden:
>    https://github.com/gpac/ComplianceWarden
> 
> Fixes the encoder/muxer part of Trac Ticket #7621
> 
> Signed-off-by: Vignesh Venkatasubramanian <vigneshv at google.com>
> ---
>  configure                |   1 +
>  libavformat/allformats.c |   1 +
>  libavformat/movenc.c     | 323 ++++++++++++++++++++++++++++++++++++---
>  libavformat/movenc.h     |   5 +
>  4 files changed, 305 insertions(+), 25 deletions(-)
> 
> diff --git a/configure b/configure
> index 8c69ab0c86..6d7020e96b 100755
> --- a/configure
> +++ b/configure
> @@ -3390,6 +3390,7 @@ asf_stream_muxer_select="asf_muxer"
>  av1_demuxer_select="av1_frame_merge_bsf av1_parser"
>  avi_demuxer_select="riffdec exif"
>  avi_muxer_select="riffenc"
> +avif_muxer_select="mov_muxer"
>  caf_demuxer_select="iso_media"
>  caf_muxer_select="iso_media"
>  dash_muxer_select="mp4_muxer"
> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
> index d066a7745b..400c17afbd 100644
> --- a/libavformat/allformats.c
> +++ b/libavformat/allformats.c
> @@ -81,6 +81,7 @@ extern const AVOutputFormat ff_au_muxer;
>  extern const AVInputFormat  ff_av1_demuxer;
>  extern const AVInputFormat  ff_avi_demuxer;
>  extern const AVOutputFormat ff_avi_muxer;
> +extern const AVOutputFormat ff_avif_muxer;
>  extern const AVInputFormat  ff_avisynth_demuxer;
>  extern const AVOutputFormat ff_avm2_muxer;
>  extern const AVInputFormat  ff_avr_demuxer;
> diff --git a/libavformat/movenc.c b/libavformat/movenc.c
> index 1a746a67fd..504403ab0b 100644
> --- a/libavformat/movenc.c
> +++ b/libavformat/movenc.c
> @@ -1303,7 +1303,7 @@ static int mov_write_av1c_tag(AVIOContext *pb, MOVTrack *track)
>  
>      avio_wb32(pb, 0);
>      ffio_wfourcc(pb, "av1C");
> -    ff_isom_write_av1c(pb, track->vos_data, track->vos_len, 1);
> +    ff_isom_write_av1c(pb, track->vos_data, track->vos_len, track->mode != MODE_AVIF);
>      return update_size(pb, pos);
>  }
>  
> @@ -2004,12 +2004,13 @@ static int mov_write_colr_tag(AVIOContext *pb, MOVTrack *track, int prefer_icc)
>          }
>      }
>  
> -    /* We should only ever be called by MOV or MP4. */
> -    av_assert0(track->mode == MODE_MOV || track->mode == MODE_MP4);
> +    /* We should only ever be called for MOV, MP4 and AVIF. */
> +    av_assert0(track->mode == MODE_MOV || track->mode == MODE_MP4 ||
> +               track->mode == MODE_AVIF);
>  
>      avio_wb32(pb, 0); /* size */
>      ffio_wfourcc(pb, "colr");
> -    if (track->mode == MODE_MP4)
> +    if (track->mode == MODE_MP4 || track->mode == MODE_AVIF)
>          ffio_wfourcc(pb, "nclx");
>      else
>          ffio_wfourcc(pb, "nclc");
> @@ -2019,7 +2020,7 @@ static int mov_write_colr_tag(AVIOContext *pb, MOVTrack *track, int prefer_icc)
>      avio_wb16(pb, track->par->color_primaries);
>      avio_wb16(pb, track->par->color_trc);
>      avio_wb16(pb, track->par->color_space);
> -    if (track->mode == MODE_MP4) {
> +    if (track->mode == MODE_MP4 || track->mode == MODE_AVIF) {
>          int full_range = track->par->color_range == AVCOL_RANGE_JPEG;
>          avio_w8(pb, full_range << 7);
>      }
> @@ -2085,7 +2086,7 @@ static void find_compressor(char * compressor_name, int len, MOVTrack *track)
>                    || (track->par->width == 1440 && track->par->height == 1080)
>                    || (track->par->width == 1920 && track->par->height == 1080);
>  
> -    if (track->mode == MODE_MOV &&
> +    if ((track->mode == MODE_AVIF || track->mode == MODE_MOV) &&
>          (encoder = av_dict_get(track->st->metadata, "encoder", NULL, 0))) {
>          av_strlcpy(compressor_name, encoder->value, 32);
>      } else if (track->par->codec_id == AV_CODEC_ID_MPEG2VIDEO && xdcam_res) {
> @@ -2106,6 +2107,25 @@ static void find_compressor(char * compressor_name, int len, MOVTrack *track)
>      }
>  }
>  
> +static int mov_write_ccst_tag(AVIOContext *pb)
> +{
> +    int64_t pos = avio_tell(pb);
> +    // Write sane defaults:
> +    // all_ref_pics_intra = 0 : all samples can use any type of reference.
> +    // intra_pred_used = 1 : intra prediction may or may not be used.
> +    // max_ref_per_pic = 15 : reserved value to indicate that any number of
> +    //                        reference images can be used.
> +    uint8_t ccstValue = (0 << 7) |  /* all_ref_pics_intra */
> +                        (1 << 6) |  /* intra_pred_used */
> +                        (15 << 2);  /* max_ref_per_pic */
> +    avio_wb32(pb, 0); /* size */
> +    ffio_wfourcc(pb, "ccst");
> +    avio_wb32(pb, 0); /* Version & flags */
> +    avio_w8(pb, ccstValue);
> +    avio_wb24(pb, 0);  /* reserved */
> +    return update_size(pb, pos);
> +}
> +
>  static int mov_write_video_tag(AVFormatContext *s, AVIOContext *pb, MOVMuxContext *mov, MOVTrack *track)
>  {
>      int ret = AVERROR_BUG;
> @@ -2123,6 +2143,8 @@ static int mov_write_video_tag(AVFormatContext *s, AVIOContext *pb, MOVMuxContex
>      avio_wb32(pb, 0); /* size */
>      if (mov->encryption_scheme != MOV_ENC_NONE) {
>          ffio_wfourcc(pb, "encv");
> +    } else if (track->mode == MODE_AVIF) {
> +        ffio_wfourcc(pb, "av01");
>      } else {
>          avio_wl32(pb, track->tag); // store it byteswapped
>      }
> @@ -2239,7 +2261,7 @@ static int mov_write_video_tag(AVFormatContext *s, AVIOContext *pb, MOVMuxContex
>          else
>              av_log(mov->fc, AV_LOG_WARNING, "Not writing 'gama' atom. Format is not MOV.\n");
>      }
> -    if (track->mode == MODE_MOV || track->mode == MODE_MP4) {
> +    if (track->mode == MODE_MOV || track->mode == MODE_MP4 || track->mode == MODE_AVIF) {
>          int has_color_info = track->par->color_primaries != AVCOL_PRI_UNSPECIFIED &&
>                               track->par->color_trc != AVCOL_TRC_UNSPECIFIED &&
>                               track->par->color_space != AVCOL_SPC_UNSPECIFIED;
> @@ -2291,6 +2313,9 @@ static int mov_write_video_tag(AVFormatContext *s, AVIOContext *pb, MOVMuxContex
>      if (avid)
>          avio_wb32(pb, 0);
>  
> +    if (track->mode == MODE_AVIF)
> +        mov_write_ccst_tag(pb);
> +
>      return update_size(pb, pos);
>  }
>  
> @@ -2792,7 +2817,10 @@ static int mov_write_hdlr_tag(AVFormatContext *s, AVIOContext *pb, MOVTrack *tra
>  
>      if (track) {
>          hdlr = (track->mode == MODE_MOV) ? "mhlr" : "\0\0\0\0";
> -        if (track->par->codec_type == AVMEDIA_TYPE_VIDEO) {
> +        if (track->mode == MODE_AVIF) {
> +            hdlr_type = "pict";
> +            descr = "ffmpeg";
> +        } else if (track->par->codec_type == AVMEDIA_TYPE_VIDEO) {
>              hdlr_type = "vide";
>              descr     = "VideoHandler";
>          } else if (track->par->codec_type == AVMEDIA_TYPE_AUDIO) {
> @@ -2859,6 +2887,131 @@ static int mov_write_hdlr_tag(AVFormatContext *s, AVIOContext *pb, MOVTrack *tra
>      return update_size(pb, pos);
>  }
>  
> +static int mov_write_pitm_tag(AVIOContext *pb, int item_id)
> +{
> +    int64_t pos = avio_tell(pb);
> +    avio_wb32(pb, 0); /* size */
> +    ffio_wfourcc(pb, "pitm");
> +    avio_wb32(pb, 0); /* Version & flags */
> +    avio_wb16(pb, item_id); /* item_id */
> +    return update_size(pb, pos);
> +}
> +
> +static int mov_write_iloc_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s)
> +{
> +    int64_t pos = avio_tell(pb);
> +    avio_wb32(pb, 0); /* size */
> +    ffio_wfourcc(pb, "iloc");
> +    avio_wb32(pb, 0); /* Version & flags */
> +    avio_w8(pb, (4 << 4) + 4); /* offset_size(4) and length_size(4) */
> +    avio_w8(pb, 0); /* base_offset_size(4) and reserved(4) */
> +    avio_wb16(pb, 1); /* item_count */
> +
> +    avio_wb16(pb, 1); /* item_id */
> +    avio_wb16(pb, 0); /* data_reference_index */
> +    avio_wb16(pb, 1); /* extent_count */
> +    mov->avif_extent_pos = avio_tell(pb);
> +    avio_wb32(pb, 0); /* extent_offset (written later) */
> +    // For animated AVIF, we simply write the first packet's size.
> +    avio_wb32(pb, mov->avif_extent_length); /* extent_length */
> +
> +    return update_size(pb, pos);
> +}
> +
> +static int mov_write_iinf_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s)
> +{
> +    int64_t infe_pos;
> +    int64_t iinf_pos = avio_tell(pb);
> +    avio_wb32(pb, 0); /* size */
> +    ffio_wfourcc(pb, "iinf");
> +    avio_wb32(pb, 0); /* Version & flags */
> +    avio_wb16(pb, 1); /* entry_count */
> +
> +    infe_pos = avio_tell(pb);
> +    avio_wb32(pb, 0); /* size */
> +    ffio_wfourcc(pb, "infe");
> +    avio_w8(pb, 0x2); /* Version */
> +    avio_wb24(pb, 0); /* flags */
> +    avio_wb16(pb, 1); /* item_id */
> +    avio_wb16(pb, 0); /* item_protection_index */
> +    avio_write(pb, "av01", 4); /* item_type */
> +    avio_write(pb, "Color\0", 6); /* item_name */
> +    update_size(pb, infe_pos);
> +
> +    return update_size(pb, iinf_pos);
> +}
> +
> +static int mov_write_ispe_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s)
> +{
> +    int64_t pos = avio_tell(pb);
> +    avio_wb32(pb, 0); /* size */
> +    ffio_wfourcc(pb, "ispe");
> +    avio_wb32(pb, 0); /* Version & flags */
> +    avio_wb32(pb, s->streams[0]->codecpar->width); /* image_width */
> +    avio_wb32(pb, s->streams[0]->codecpar->height); /* image_height */
> +    return update_size(pb, pos);
> +}
> +
> +
> +static int mov_write_pixi_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s)
> +{
> +    int64_t pos = avio_tell(pb);
> +    int num_channels = av_pix_fmt_count_planes(s->streams[0]->codecpar->format);
> +    const AVPixFmtDescriptor *pixdesc = av_pix_fmt_desc_get(s->streams[0]->codecpar->format);
> +    int i;
> +    avio_wb32(pb, 0); /* size */
> +    ffio_wfourcc(pb, "pixi");
> +    avio_wb32(pb, 0); /* Version & flags */
> +    avio_w8(pb, num_channels); /* num_channels */
> +    for (i = 0; i < num_channels; ++i) {
> +      avio_w8(pb, pixdesc->comp[i].depth); /* bits_per_channel */
> +    }
> +    return update_size(pb, pos);
> +}
> +
> +static int mov_write_ipco_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s)
> +{
> +    int64_t pos = avio_tell(pb);
> +    avio_wb32(pb, 0); /* size */
> +    ffio_wfourcc(pb, "ipco");
> +    mov_write_ispe_tag(pb, mov, s);
> +    mov_write_pixi_tag(pb, mov, s);
> +    mov_write_av1c_tag(pb, &mov->tracks[0]);
> +    mov_write_colr_tag(pb, &mov->tracks[0], 0);
> +    return update_size(pb, pos);
> +}
> +
> +static int mov_write_ipma_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s)
> +{
> +    int64_t pos = avio_tell(pb);
> +    avio_wb32(pb, 0); /* size */
> +    ffio_wfourcc(pb, "ipma");
> +    avio_wb32(pb, 0); /* Version & flags */
> +    avio_wb32(pb, 1); /* entry_count */
> +    avio_wb16(pb, 1); /* item_ID */
> +    avio_w8(pb, 4); /* association_count */
> +
> +    // ispe association.
> +    avio_w8(pb, 1); /* essential and property_index */
> +    // pixi association.
> +    avio_w8(pb, 2); /* essential and property_index */
> +    // av1C association.
> +    avio_w8(pb, 0x80 | 3); /* essential and property_index */
> +    // colr association.
> +    avio_w8(pb, 4); /* essential and property_index */
> +    return update_size(pb, pos);
> +}
> +
> +static int mov_write_iprp_tag(AVIOContext *pb, MOVMuxContext *mov, AVFormatContext *s)
> +{
> +    int64_t pos = avio_tell(pb);
> +    avio_wb32(pb, 0); /* size */
> +    ffio_wfourcc(pb, "iprp");
> +    mov_write_ipco_tag(pb, mov, s);
> +    mov_write_ipma_tag(pb, mov, s);
> +    return update_size(pb, pos);
> +}
> +
>  static int mov_write_hmhd_tag(AVIOContext *pb)
>  {
>      /* This atom must be present, but leaving the values at zero
> @@ -3056,7 +3209,7 @@ static int mov_write_tkhd_tag(AVIOContext *pb, MOVMuxContext *mov,
>              display_matrix = NULL;
>      }
>  
> -    if (track->flags & MOV_TRACK_ENABLED)
> +    if (track->flags & MOV_TRACK_ENABLED || track->mode == MODE_AVIF)
>          flags |= MOV_TKHD_FLAG_ENABLED;
>  
>      if (track->mode == MODE_ISM)
> @@ -3104,7 +3257,7 @@ static int mov_write_tkhd_tag(AVIOContext *pb, MOVMuxContext *mov,
>      if (st && (track->par->codec_type == AVMEDIA_TYPE_VIDEO ||
>                 track->par->codec_type == AVMEDIA_TYPE_SUBTITLE)) {
>          int64_t track_width_1616;
> -        if (track->mode == MODE_MOV) {
> +        if (track->mode == MODE_MOV || track->mode == MODE_AVIF) {
>              track_width_1616 = track->par->width * 0x10000ULL;
>          } else {
>              track_width_1616 = av_rescale(st->sample_aspect_ratio.num,
> @@ -3439,7 +3592,8 @@ static int mov_write_trak_tag(AVFormatContext *s, AVIOContext *pb, MOVMuxContext
>              mov_write_tapt_tag(pb, track);
>          }
>      }
> -    mov_write_track_udta_tag(pb, mov, st);
> +    if (track->mode != MODE_AVIF)
> +        mov_write_track_udta_tag(pb, mov, st);
>      track->entry = entry_backup;
>      track->chunkCount = chunk_backup;
>      return update_size(pb, pos);
> @@ -3914,8 +4068,15 @@ static int mov_write_meta_tag(AVIOContext *pb, MOVMuxContext *mov,
>          mov_write_mdta_hdlr_tag(pb, mov, s);
>          mov_write_mdta_keys_tag(pb, mov, s);
>          mov_write_mdta_ilst_tag(pb, mov, s);
> -    }
> -    else {
> +    } else if (mov->mode == MODE_AVIF) {
> +        mov_write_hdlr_tag(s, pb, &mov->tracks[0]);
> +        // We always write the primary item id as 1 since only one track is
> +        // supported for AVIF.

Various parts of this patch seem to presume this (they always use the
first stream), yet I fail to see what ensures this.

> +        mov_write_pitm_tag(pb, 1);
> +        mov_write_iloc_tag(pb, mov, s);
> +        mov_write_iinf_tag(pb, mov, s);
> +        mov_write_iprp_tag(pb, mov, s);
> +    } else {
>          /* iTunes metadata tag */
>          mov_write_itunes_hdlr_tag(pb, mov, s);
>          mov_write_ilst_tag(pb, mov, s);
> @@ -4245,10 +4406,11 @@ static int mov_write_moov_tag(AVIOContext *pb, MOVMuxContext *mov,
>      }
>  
>      mov_write_mvhd_tag(pb, mov);
> -    if (mov->mode != MODE_MOV && !mov->iods_skip)
> +    if (mov->mode != MODE_MOV && mov->mode != MODE_AVIF && !mov->iods_skip)
>          mov_write_iods_tag(pb, mov);
>      for (i = 0; i < mov->nb_streams; i++) {
> -        if (mov->tracks[i].entry > 0 || mov->flags & FF_MOV_FLAG_FRAGMENT) {
> +        if (mov->tracks[i].entry > 0 || mov->flags & FF_MOV_FLAG_FRAGMENT ||
> +            mov->mode == MODE_AVIF) {
>              int ret = mov_write_trak_tag(s, pb, mov, &(mov->tracks[i]), i < s->nb_streams ? s->streams[i] : NULL);
>              if (ret < 0)
>                  return ret;
> @@ -4259,7 +4421,7 @@ static int mov_write_moov_tag(AVIOContext *pb, MOVMuxContext *mov,
>  
>      if (mov->mode == MODE_PSP)
>          mov_write_uuidusmt_tag(pb, s);
> -    else
> +    else if (mov->mode != MODE_AVIF)
>          mov_write_udta_tag(pb, mov, s);
>  
>      return update_size(pb, pos);
> @@ -5002,6 +5164,9 @@ static void mov_write_ftyp_tag_internal(AVIOContext *pb, AVFormatContext *s,
>      else if (mov->mode == MODE_3GP) {
>          ffio_wfourcc(pb, has_h264 ? "3gp6"  : "3gp4");
>          minor =     has_h264 ?   0x100 :   0x200;
> +    } else if (mov->mode == MODE_AVIF) {
> +        ffio_wfourcc(pb, mov->is_animated_avif ? "avis" : "avif");
> +        minor = 0;
>      } else if (mov->mode & MODE_3G2) {
>          ffio_wfourcc(pb, has_h264 ? "3g2b"  : "3g2a");
>          minor =     has_h264 ? 0x20000 : 0x10000;
> @@ -5065,6 +5230,31 @@ static int mov_write_ftyp_tag(AVIOContext *pb, AVFormatContext *s)
>      // compatible brand a second time.
>      if (mov->mode == MODE_ISM) {
>          ffio_wfourcc(pb, "piff");
> +    } else if (mov->mode == MODE_AVIF) {
> +        const AVPixFmtDescriptor *pix_fmt_desc =
> +            av_pix_fmt_desc_get(s->streams[0]->codecpar->format);
> +        const int depth = pix_fmt_desc->comp[0].depth;
> +        if (mov->is_animated_avif) {
> +            // For animated AVIF, major brand is "avis". Add "avif" as a
> +            // compatible brand.
> +            ffio_wfourcc(pb, "avif");
> +            ffio_wfourcc(pb, "msf1");
> +            ffio_wfourcc(pb, "iso8");
> +        }
> +        ffio_wfourcc(pb, "mif1");
> +        ffio_wfourcc(pb, "miaf");
> +        if (depth == 8 || depth == 10) {
> +            // MA1B and MA1A brands are based on AV1 profile. Short hand for
> +            // computing that is based on chroma subsampling type. 420 chroma
> +            // subsampling is MA1B.  444 chroma subsampling is MA1A.
> +            if (pix_fmt_desc->log2_chroma_w == 0 && pix_fmt_desc->log2_chroma_h == 0) {
> +                // 444 chroma subsampling.
> +                ffio_wfourcc(pb, "MA1A");
> +            } else {
> +                // 420 chroma subsampling.
> +                ffio_wfourcc(pb, "MA1B");
> +            }
> +        }
>      } else if (mov->mode != MODE_MOV) {
>          // We add tfdt atoms when fragmenting, signal this with the iso6 compatible
>          // brand, if not already the major brand. This is compatible with users that
> @@ -5669,7 +5859,7 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt)
>      if (ret < 0)
>          return ret;
>  
> -    if (mov->flags & FF_MOV_FLAG_FRAGMENT) {
> +    if (mov->flags & FF_MOV_FLAG_FRAGMENT || mov->mode == MODE_AVIF) {
>          int ret;
>          if (mov->moov_written || mov->flags & FF_MOV_FLAG_EMPTY_MOOV) {
>              if (mov->frag_interleave && mov->fragments > 0) {
> @@ -5802,7 +5992,9 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt)
>              }
>          }
>      } else if (par->codec_id == AV_CODEC_ID_AV1) {
> -        if (trk->hint_track >= 0 && trk->hint_track < mov->nb_streams) {
> +        if (trk->mode == MODE_AVIF) {
> +            avio_write(pb, pkt->data, pkt->size);
> +        } else if (trk->hint_track >= 0 && trk->hint_track < mov->nb_streams) {
>              ret = ff_av1_filter_obus_buf(pkt->data, &reformatted_data,
>                                           &size, &offset);
>              if (ret < 0)
> @@ -6230,6 +6422,10 @@ fail:
>              }
>          }
>  
> +        if (trk->mode == MODE_AVIF && !mov->avif_extent_length) {
> +            mov->avif_extent_length = pkt->size;
> +        }
> +
>          return mov_write_single_packet(s, pkt);
>      }
>  }
> @@ -6569,11 +6765,15 @@ static int mov_init(AVFormatContext *s)
>      else if (IS_MODE(ipod, IPOD)) mov->mode = MODE_IPOD;
>      else if (IS_MODE(ismv, ISMV)) mov->mode = MODE_ISM;
>      else if (IS_MODE(f4v,   F4V)) mov->mode = MODE_F4V;
> +    else if (IS_MODE(avif, AVIF)) mov->mode = MODE_AVIF;
>  #undef IS_MODE
>  
>      if (mov->flags & FF_MOV_FLAG_DELAY_MOOV)
>          mov->flags |= FF_MOV_FLAG_EMPTY_MOOV;
>  
> +    if (mov->mode == MODE_AVIF)
> +        mov->flags |= FF_MOV_FLAG_DELAY_MOOV;
> +
>      /* Set the FRAGMENT flag if any of the fragmentation methods are
>       * enabled. */
>      if (mov->max_fragment_duration || mov->max_fragment_size ||
> @@ -6797,12 +6997,13 @@ static int mov_init(AVFormatContext *s)
>                          pix_fmt == AV_PIX_FMT_MONOWHITE ||
>                          pix_fmt == AV_PIX_FMT_MONOBLACK;
>              }
> -            if (track->par->codec_id == AV_CODEC_ID_VP9 ||
> -                track->par->codec_id == AV_CODEC_ID_AV1) {
> -                if (track->mode != MODE_MP4) {
> -                    av_log(s, AV_LOG_ERROR, "%s only supported in MP4.\n", avcodec_get_name(track->par->codec_id));
> -                    return AVERROR(EINVAL);
> -                }
> +            if (track->par->codec_id == AV_CODEC_ID_VP9 && track->mode != MODE_MP4) {
> +                av_log(s, AV_LOG_ERROR, "%s only supported in MP4.\n", avcodec_get_name(track->par->codec_id));
> +		return AVERROR(EINVAL);
> +            } else if (track->par->codec_id == AV_CODEC_ID_AV1 &&
> +                       track->mode != MODE_MP4 && track->mode != MODE_AVIF) {
> +                av_log(s, AV_LOG_ERROR, "%s only supported in MP4 and AVIF.\n", avcodec_get_name(track->par->codec_id));
> +                return AVERROR(EINVAL);
>              } else if (track->par->codec_id == AV_CODEC_ID_VP8) {
>                  /* altref frames handling is not defined in the spec as of version v1.0,
>                   * so just forbid muxing VP8 streams altogether until a new version does */
> @@ -7003,7 +7204,7 @@ static int mov_write_header(AVFormatContext *s)
>                              FF_MOV_FLAG_FRAG_EVERY_FRAME)) &&
>              !mov->max_fragment_duration && !mov->max_fragment_size)
>              mov->flags |= FF_MOV_FLAG_FRAG_KEYFRAME;
> -    } else {
> +    } else if (mov->mode != MODE_AVIF) {
>          if (mov->flags & FF_MOV_FLAG_FASTSTART)
>              mov->reserved_header_pos = avio_tell(pb);
>          mov_write_mdat_tag(pb, mov);
> @@ -7291,6 +7492,54 @@ static int mov_check_bitstream(AVFormatContext *s, AVStream *st,
>      return ret;
>  }
>  
> +static int avif_write_trailer(AVFormatContext *s)
> +{
> +    AVIOContext *pb = s->pb;
> +    MOVMuxContext *mov = s->priv_data;
> +    int64_t pos_backup, mdat_pos;
> +    uint8_t *buf;
> +    int buf_size, moov_size;
> +    int i;
> +
> +    if (mov->moov_written) return 0;
> +
> +    mov->is_animated_avif = s->streams[0]->nb_frames > 1;
> +    mov_write_identification(pb, s);
> +    mov_write_meta_tag(pb, mov, s);
> +
> +    moov_size = get_moov_size(s);
> +    for (i = 0; i < mov->nb_streams; i++)
> +        mov->tracks[i].data_offset = avio_tell(pb) + moov_size + 8;
> +
> +    if (mov->is_animated_avif) {
> +        int ret;
> +        if ((ret = mov_write_moov_tag(pb, mov, s)) < 0)
> +            return ret;
> +    }
> +
> +    buf_size = avio_get_dyn_buf(mov->mdat_buf, &buf);
> +    avio_wb32(pb, buf_size + 8);
> +    ffio_wfourcc(pb, "mdat");
> +    mdat_pos = avio_tell(pb);
> +
> +    avio_write(pb, buf, buf_size);
> +    ffio_free_dyn_buf(&mov->mdat_buf);
> +
> +    // write extent offset.
> +    pos_backup = avio_tell(pb);
> +    avio_seek(pb, mov->avif_extent_pos, SEEK_SET);
> +    avio_wb32(pb, mdat_pos); /* rewrite offset */
> +    avio_seek(pb, pos_backup, SEEK_SET);
> +
> +    mov->moov_written = 1;
> +    mov->mdat_size = 0;
> +    for (i = 0; i < mov->nb_streams; i++) {
> +        mov->tracks[i].entry = 0;
> +        mov->tracks[i].end_reliable = 0;
> +    }

Why this? write_trailer is only called once.

> +    return 0;
> +}> +
>  #if CONFIG_TGP_MUXER || CONFIG_TG2_MUXER
>  static const AVCodecTag codec_3gp_tags[] = {
>      { AV_CODEC_ID_H263,     MKTAG('s','2','6','3') },
> @@ -7373,6 +7622,12 @@ static const AVCodecTag codec_f4v_tags[] = {
>      { AV_CODEC_ID_NONE, 0 },
>  };
>  
> +static const AVCodecTag codec_avif_tags[] = {
> +    { AV_CODEC_ID_AV1,     MKTAG('a','v','0','1') },
> +    { AV_CODEC_ID_NONE, 0 },
> +};
> +static const AVCodecTag *const codec_avif_tags_list[] = { codec_avif_tags, NULL };

Why is this not under #if CONFIG_AVIF_MUXER (or part of the other #if
CONFIG_AVIF_MUXER below)?

> +
>  #if CONFIG_MOV_MUXER
>  const AVOutputFormat ff_mov_muxer = {
>      .name              = "mov",
> @@ -7535,3 +7790,21 @@ const AVOutputFormat ff_f4v_muxer = {
>      .priv_class        = &mov_isobmff_muxer_class,
>  };
>  #endif
> +#if CONFIG_AVIF_MUXER
> +const AVOutputFormat ff_avif_muxer = {
> +    .name              = "avif",
> +    .long_name         = NULL_IF_CONFIG_SMALL("AVIF"),
> +    .mime_type         = "image/avif",
> +    .extensions        = "avif",
> +    .priv_data_size    = sizeof(MOVMuxContext),
> +    .video_codec       = AV_CODEC_ID_AV1,
> +    .init              = mov_init,
> +    .write_header      = mov_write_header,
> +    .write_packet      = mov_write_packet,
> +    .write_trailer     = avif_write_trailer,
> +    .deinit            = mov_free,
> +    .flags             = AVFMT_GLOBALHEADER | AVFMT_ALLOW_FLUSH,
> +    .codec_tag         = codec_avif_tags_list,
> +    .priv_class        = &mov_isobmff_muxer_class,

This gives this muxer all the options of the other muxers; yet which one
of these are actually supported? E.g. is faststart supported? The code
for it is in mov_write_trailer() and that is not called.

> +};
> +#endif
> diff --git a/libavformat/movenc.h b/libavformat/movenc.h
> index 2ac84ed070..55b8469f68 100644
> --- a/libavformat/movenc.h
> +++ b/libavformat/movenc.h
> @@ -43,6 +43,7 @@
>  #define MODE_IPOD 0x20
>  #define MODE_ISM  0x40
>  #define MODE_F4V  0x80
> +#define MODE_AVIF 0x100
>  
>  typedef struct MOVIentry {
>      uint64_t     pos;
> @@ -242,6 +243,10 @@ typedef struct MOVMuxContext {
>      MOVPrftBox write_prft;
>      int empty_hdlr_name;
>      int movie_timescale;
> +
> +    int64_t avif_extent_pos;
> +    int avif_extent_length;
> +    int is_animated_avif;
>  } MOVMuxContext;
>  
>  #define FF_MOV_FLAG_RTP_HINT              (1 <<  0)



More information about the ffmpeg-devel mailing list