[FFmpeg-devel] [PATCH] avcodec/bsf/h264_mp4toannexb.c: change extradata to annexb if this is avcc.

[jie jiang]

I resubmitted it according to your suggestion.
please check.
https://patchwork.ffmpeg.org/project/ffmpeg/patch/20250424124250.71553-1-jiangjie618@gmail.com/


So only remove AV_PKT_DATA_NEW_EXTRADATA can fix the issue?
answer:  yes,  but AV_PKT_DATA_NEW_EXTRADATA is used for event
notification, it is usefull.

And the error is from bsf or decoder after h264_mp4toannexb, not
h264_mp4toannexb itself, right?
answer:  yes

i think AV_PKT_DATA_NEW_EXTRADATA and output stream should be the same
format, both avvc or  annexb.




On Thu, Apr 24, 2025 at 8:43 PM jiangjie <jiangjie618 at gmail.com> wrote:

> if get AV_PKT_DATA_NEW_EXTRADATA in AVPacket, this bitstream filter will
> return an error.
> ffmpeg -i rtmp://xxx/live/xxx -bsf:v
> "h264_mp4toannexb,h264_metadata=aud=remove" -c copy -f null -
> ---
>  libavcodec/bsf/h264_mp4toannexb.c             | 26 ++++++++++++++-----
>  tests/fate/h264.mak                           |  3 +++
>  .../fate/h264-bsf-mp4toannexb-h264_metadata   | 12 +++++++++
>  3 files changed, 35 insertions(+), 6 deletions(-)
>  create mode 100644 tests/ref/fate/h264-bsf-mp4toannexb-h264_metadata
>
> diff --git a/libavcodec/bsf/h264_mp4toannexb.c
> b/libavcodec/bsf/h264_mp4toannexb.c
> index dda064287e..42a5a274bf 100644
> --- a/libavcodec/bsf/h264_mp4toannexb.c
> +++ b/libavcodec/bsf/h264_mp4toannexb.c
> @@ -252,14 +252,21 @@ static int h264_mp4toannexb_filter_ps(H264BSFContext
> *s,
>      return 0;
>  }
>
> +static int is_annexb(const uint8_t *extradata, int extra_size) {
> +    if (!extra_size || (extra_size >= 3 && AV_RB24(extradata) == 1) ||
> +        (extra_size >= 4 && AV_RB32(extradata) == 1)) {
> +        return 1;
> +    } else {
> +        return 0;
> +    }
> +}
> +
>  static int h264_mp4toannexb_init(AVBSFContext *ctx)
>  {
>      int extra_size = ctx->par_in->extradata_size;
>
>      /* retrieve sps and pps NAL units from extradata */
> -    if (!extra_size                                               ||
> -        (extra_size >= 3 && AV_RB24(ctx->par_in->extradata) == 1) ||
> -        (extra_size >= 4 && AV_RB32(ctx->par_in->extradata) == 1)) {
> +    if (is_annexb(ctx->par_in->extradata, extra_size)) {
>          av_log(ctx, AV_LOG_VERBOSE,
>                 "The input looks like it is Annex B already\n");
>      } else if (extra_size >= 7) {
> @@ -294,9 +301,16 @@ static int h264_mp4toannexb_filter(AVBSFContext *ctx,
> AVPacket *opkt)
>      extradata = av_packet_get_side_data(in, AV_PKT_DATA_NEW_EXTRADATA,
>                                          &extradata_size);
>      if (extradata) {
> -        ret = h264_extradata_to_annexb(ctx, extradata, extradata_size);
> -        if (ret < 0)
> -            goto fail;
> +        if (!is_annexb(extradata, extradata_size) && extradata_size >= 7)
> {
> +            ret = h264_extradata_to_annexb(ctx, extradata,
> extradata_size);
> +            if (ret < 0)
> +                goto fail;
> +            av_packet_side_data_remove(in->side_data,
> &in->side_data_elems,
> +                                       AV_PKT_DATA_NEW_EXTRADATA);
> +            uint8_t *data = av_packet_new_side_data(
> +                in, AV_PKT_DATA_NEW_EXTRADATA,
> ctx->par_out->extradata_size);
> +            memcpy(data, ctx->par_out->extradata,
> ctx->par_out->extradata_size);
> +        }
>      }
>
>      /* nothing to filter */
> diff --git a/tests/fate/h264.mak b/tests/fate/h264.mak
> index 00b153cc93..7b3e865955 100644
> --- a/tests/fate/h264.mak
> +++ b/tests/fate/h264.mak
> @@ -231,6 +231,7 @@ FATE_H264-$(call DEMMUX, MOV, H264,
> H264_MP4TOANNEXB_BSF) += fate-h264-bsf-mp4to
>
> fate-h264-bsf-mp4toannexb-2 \
>
> fate-h264_mp4toannexb_ticket5927 \
>
> fate-h264_mp4toannexb_ticket5927_2 \
> +
>  fate-h264-bsf-mp4toannexb-h264_metadata \
>
>  FATE_H264-$(call DEMMUX, H264, MOV, DTS2PTS_BSF) += fate-h264-bsf-dts2pts
>
> @@ -441,6 +442,8 @@ fate-h264-bsf-mp4toannexb-2:                      CMD
> = md5 -i $(TARGET_SAMPLES)
>  fate-h264-bsf-mp4toannexb-2:                      CMP = oneline
>  fate-h264-bsf-mp4toannexb-2:                      REF =
> cffcfa6a2d0b58c9de1f5785f099f41d
>  fate-h264-bsf-mp4toannexb-new-extradata:          CMD = stream_remux mov
> $(TARGET_SAMPLES)/h264/extradata-reload-multi-stsd.mov "" h264 "-map 0:v"
> +fate-h264-bsf-mp4toannexb-h264_metadata:          CMD = transcode mov
> $(TARGET_SAMPLES)/h264/extradata-reload-multi-stsd.mov \
> +                                                        h264 "-c:v copy
> -bsf:v h264_mp4toannexb,h264_metadata=aud=remove" "-c:v copy"
>  fate-h264-bsf-dts2pts:                            CMD = transcode "h264"
> $(TARGET_SAMPLES)/h264-conformance/CAPAMA3_Sand_F.264 \
>                                                          mov "-c:v copy
> -bsf:v dts2pts -frames:v 50" "-c:v copy"
>  fate-h264_mp4toannexb_ticket5927:                 CMD = transcode "mp4"
> $(TARGET_SAMPLES)/h264/thezerotheorem-cut.mp4 \
> diff --git a/tests/ref/fate/h264-bsf-mp4toannexb-h264_metadata
> b/tests/ref/fate/h264-bsf-mp4toannexb-h264_metadata
> new file mode 100644
> index 0000000000..d3ba7f1886
> --- /dev/null
> +++ b/tests/ref/fate/h264-bsf-mp4toannexb-h264_metadata
> @@ -0,0 +1,12 @@
> +a48f175bf3458410d1dd1907682b92d3
> *tests/data/fate/h264-bsf-mp4toannexb-h264_metadata.h264
> +4642 tests/data/fate/h264-bsf-mp4toannexb-h264_metadata.h264
> +#extradata 0:       38, 0x84d70914
> +#tb 0: 1/1200000
> +#media_type 0: video
> +#codec_id 0: h264
> +#dimensions 0: 256x128
> +#sar 0: 1/1
> +0,     -96000, -9223372036854775808,    48000,     2331, 0xc97509cb
> +0,     -48000, -9223372036854775808,    48000,       64, 0x6ad91f4e, F=0x0
> +0,          0, -9223372036854775808,    48000,     2203, 0xe376d2a9
> +0,      48000, -9223372036854775808,    48000,       44, 0x687a10ea, F=0x0
> --
> 2.49.0
>
>