On Mon, 29 Sep 2014 20:25:47 +0200 Michael Niedermayer <michae...@gmx.at> wrote:
> On Mon, Sep 29, 2014 at 07:41:28PM +0200, wm4 wrote: > > Useful for Bluray and DVD, since the libraries used to read them just > > change the byte stream under your feet on seeking. > > > > Maybe there should be a AVInputFormat callback for this. But the > > mpeg-ps (DVD) and the mpeg-ts (Bluray) demuxers don't change much > > state during seeking - they just try to find a new packet with > > timestamps (in read_timestamp), so I haven't found a need for this > > yet. I don't want to add unused things. > > > > I've also thought about adding a flush callback, and implementing > > them in mpeg.c and mpegts.c by just calling ff_read_frame_flush(). > > Might be slightly better, because you can have avformat_flush() fail > > on formats which don't support this? > > > > Or maybe a flag? > > > > TODO: add entry to APIchanges, bump minor version. > > --- > > libavformat/avformat.h | 13 +++++++++++++ > > libavformat/utils.c | 6 ++++++ > > 2 files changed, 19 insertions(+) > > > > diff --git a/libavformat/avformat.h b/libavformat/avformat.h > > index 78054de..eaa52fa 100644 > > --- a/libavformat/avformat.h > > +++ b/libavformat/avformat.h > > @@ -2173,6 +2173,19 @@ int av_seek_frame(AVFormatContext *s, int > > stream_index, int64_t timestamp, > > int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t > > min_ts, int64_t ts, int64_t max_ts, int flags); > > > > /** > > + * Discard all internally buffered data. This can be useful when dealing > > with > > + * discontinuities in the byte stream. Generally works only with some > > simple > > + * formats. > > id call them stream based or without a central header instead of > simple. I can change that and replace "simple" with "headerless". > > > + * > > + * This does not flush the AVIOContext (s->pb). If necessary, call > > + * avio_flush(s->pb) before calling this function. > > + * > > + * @param s media file handle > > + * @return >=0 on success, error code otherwise > > + */ > > +int avformat_flush(AVFormatContext *s); > > i think this should document what happens with the streams > are they flushed too so that nb_streams could decrease ... > i guess the case where they could decrease doesnt make much sense > as that can already be achived by closing the demuxer and reopening > it ... Removing the AVStreams would be not useful; keeping the streams around is in fact this is the reason why reopening might not work, and avformat_flush() is needed at all. I can add something to the doxygen to explain this. Maybe: "The set of streams, the detected duration, stream parameters and codecs do not change when calling this function." _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
