[FFmpeg-devel] FW: pts/dts generation and index for mpegts (vob)

Baptiste Coudurier baptiste.coudurier
Wed Jun 17 00:22:16 CEST 2009

Erik Van Grunderbeeck wrote:
>>> 1) Introduce a new reader (with a new namespace in case of DVD) depending
> on
>>> libdvdread (in which I fixed a few things I will forward to them).
>> By reader you mean demuxer or protocol to speak in libavformat terms.
> A protocol. Namespace (right now) is "dvdread". So you open a disk with
> "dvdread:e:/"  or "dvdread:/cdrom3/", etc


> The demuxer is extended by using stream startcode 0x1ff and checking for a
> small header id (like "EXTNAVDATA").
>> 2a) Extend the mpeg ts reader to allow commands to be send to the API
>> through a new stream type. That stream type includes "commands" to be
>> executed.
>> Will PS be supported ?
>> Is STREAM_TYPE_COMMAND needed if you use STREAM_TYPE_DATA and
> I am not sure I understand the question?

I interpreted stream type by another CODEC_TYPE_*

>> 4) Introduce a new seek flag to allow seek on chapter level, and fix the
>> end-generation for duration calculation.
>> We are reworking seeking API currently during GSOC, any ideas are
>> welcome. Maybe an AVSEEK_FLAG_CHAPTER ?
> Yes, that would be the idea. 
> Also there need to be some way's to feed commands back to the protocol. I
> know this has been discussed here before (ege the E_AGAIN thread), but it
> seems to me more devices/protocols (example video camera's, network
> broadcast layered protocol's, server's with channel switching) could benefit
> from a [generic] send command layer.

Well if that's needed, why not, simple, generic and clean but that's

Like read_seek, read_pause ? Maybe this could be made more generic.

>>> I feel using libdvdread is a good way forward. Its rather stable and
> mature,
>>> and works well on all os's. Furthermore, one simply needs a vm parser to
>>> have angle and all other features, including pts/dts discontinuities
>>> working. Rewriting another one is simply silly IMHO.
>> Well, why not, if it's clean and simple.
>> Will you work with current PS demuxer ? I think you can add a dvd
>> special demuxer but it must reuse code in PS demuxer when it can.
> It works 100% with the current demuxer.

Great then.

Baptiste COUDURIER                              GnuPG Key Id: 0x5C1ABAAA
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