[FFmpeg-devel] [PATCH] avformat/mov: fix buffering issue on playing HTTP(s)/mp4.

["zhilizhao(赵志立)"]

> On Dec 19, 2022, at 12:24, Chen, Jinkai <chenjinkai at agora.io> wrote:
> 
> Using separated HTTP connection for each stream,
> prevent from reading audio and video in long distance,
> which cause seeking(http request) repeatedly.
> Storing the user options when open input,
> and make sure that can be passed to demuxer context.

The patch is harmful for normal files, and the implementation isn’t clean, so NAK.

> 
> Some source can reproducing the issue:
> https://ali-sprite-video.yyouwang.com/video/works/202211/1667997073624_73.mp4
> https://images.voghion.com/productImages/04_01_C_30011_2020220106GiuseppeFanara0012.mp4
> 
> Signed-off-by: CJK <chenjinkai at agora.io<mailto:chenjinkai at agora.io>>
> ---
> libavformat/avformat.c |  1 +
> libavformat/demux.c    |  5 ++++-
> libavformat/internal.h |  5 +++++
> libavformat/mov.c      | 16 ++++++++++++++++
> 4 files changed, 26 insertions(+), 1 deletion(-)
> 
> diff --git a/libavformat/avformat.c b/libavformat/avformat.c
> index 19c7219471..4453727f34 100644
> --- a/libavformat/avformat.c
> +++ b/libavformat/avformat.c
> @@ -129,6 +129,7 @@ void avformat_free_context(AVFormatContext *s)
>    av_freep(&s->chapters);
>    av_dict_free(&s->metadata);
>    av_dict_free(&si->id3v2_meta);
> +    av_dict_free(&si->options);
>    av_packet_free(&si->pkt);
>    av_packet_free(&si->parse_pkt);
>    av_freep(&s->streams);
> diff --git a/libavformat/demux.c b/libavformat/demux.c
> index 2dfd82a63c..2377bfdab0 100644
> --- a/libavformat/demux.c
> +++ b/libavformat/demux.c
> @@ -237,8 +237,11 @@ int avformat_open_input(AVFormatContext **ps, const char *filename,
>    if (fmt)
>        s->iformat = fmt;
> 
> -    if (options)
> +    if (options) {
>        av_dict_copy(&tmp, *options, 0);
> +        si->options = NULL;
> +        av_dict_copy(&si->options, *options, 0);
> +    }
> 
>    if (s->pb) // must be before any goto fail
>        s->flags |= AVFMT_FLAG_CUSTOM_IO;
> diff --git a/libavformat/internal.h b/libavformat/internal.h
> index ce837fefc7..7caae8b93e 100644
> --- a/libavformat/internal.h
> +++ b/libavformat/internal.h
> @@ -186,6 +186,11 @@ typedef struct FFFormatContext {
>     * Contexts and child contexts do not contain a metadata option
>     */
>    int metafree;
> +
> +    /**
> +     * options from avformat_open_input
> +     */
> +    AVDictionary *options;
> } FFFormatContext;
> 
> static av_always_inline FFFormatContext *ffformatcontext(AVFormatContext *s)
> diff --git a/libavformat/mov.c b/libavformat/mov.c
> index 29bd3103e3..1e1a7c2f7f 100644
> --- a/libavformat/mov.c
> +++ b/libavformat/mov.c
> @@ -4456,6 +4456,7 @@ static int mov_read_trak(MOVContext *c, AVIOContext *pb, MOVAtom atom)
> {
>    AVStream *st;
>    MOVStreamContext *sc;
> +    URLContext *url_context;
>    int ret;
> 
>    st = avformat_new_stream(c->fc, NULL);
> @@ -4501,6 +4502,8 @@ static int mov_read_trak(MOVContext *c, AVIOContext *pb, MOVAtom atom)
> 
>    mov_build_index(c, st);
> 
> +    url_context = ffio_geturlcontext(c->fc->pb);
> +    av_assert0(url_context);
>    if (sc->dref_id-1 < sc->drefs_count && sc->drefs[sc->dref_id-1].path) {
>        MOVDref *dref = &sc->drefs[sc->dref_id - 1];
>        if (c->enable_drefs) {
> @@ -4510,6 +4513,19 @@ static int mov_read_trak(MOVContext *c, AVIOContext *pb, MOVAtom atom)
>                       "filename='%s', volume='%s', nlvl_from=%d, nlvl_to=%d\n",
>                       st->index, dref->path, dref->dir, dref->filename,
>                       dref->volume, dref->nlvl_from, dref->nlvl_to);
> +        } else if (strcmp(url_context->prot->name, "http") == 0 ||
> +                   strcmp(url_context->prot->name, "https") == 0) {
> +            FFFormatContext *const si = ffformatcontext(c->fc);
> +            AVDictionary *opts = NULL;
> +            av_dict_copy(&opts, si->options, 0);
> +            ret = c->fc->io_open(c->fc, &sc->pb, c->fc->url, AVIO_FLAG_READ, &opts);
> +            av_dict_free(&opts);
> +            if (ret < 0) {
> +                av_log(c->fc, AV_LOG_ERROR,
> +                    "mov/http(s) stream %d, error opening url %s.\n",
> +                    st->index, c->fc->url);
> +                return ret;
> +            }
>        } else {
>            av_log(c->fc, AV_LOG_WARNING,
>                   "Skipped opening external track: "
> --
> 2.24.3 (Apple Git-128)
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> 
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".