[gst-devel] various questions about GStreamer elements

[Ronald S. Bultje]

Hi,

On Thu, 2005-01-13 at 19:37 +0530, Thirupathiah Annapureddy wrote:
> 1. how can an application introduce the data into the pipeline with
> minimal latency.
[..]
> our long term plan would be to develop rtpsrc, demultiplexing elements
> in the GStreamer itself. Any comments on this?

If thatś the final purpose, then it´s probably OK. Be prepared for
application-data-introduction being painful. There´s docs on this topic
on http://ronald.bitfreak.net/priv/adm/section-data-spoof.html - this is
supposed to be in the manual on the GStreamer website as well, but for
some reason it does not show up... Hm...

Read the warnings. Seriously, read them.

> 2. Suppose if a pipeline has X1, X2, and X3 elements. what is the
> order of state change notification?

See the implementation. You should not depend on any particular order,
really, that is very bad habit and is not guaranteed to be stable across
versions (in theory) in the 0.8 series.

> 3. Are there any ready made queues in GStreamer so that an element can
> use to queue buffers or etc.?

Yes, queue. :). See
http://gstreamer.freedesktop.org/data/doc/gstreamer/head/manual/html/chapter-threads.html

> 4. In DirectShow, there used to be Pull Source or Push Source.
> Normally live data is transmitted into the filter graph using Push
> Source. In case of GStreamer, a source element can be _get or _loop or
> _chain type. I think _get function can be thought of as Pull Source.
> is that right? what about push kind of source? is calling
> gst_pad_push(xxxsrc->srcpad)makes the source as push?

Yes (so loop-based).

Ronald

-- 
Ronald S. Bultje <rbultje at ronald.bitfreak.net>