Playing RTSP with python-gstreamer

[lonkaji]

Hi,

I use gstreamer for playing RTSP stream from IP cameras like Axis. I use a command line like this:

gst-launch-0.10 rtspsrc location=rtsp://192.168.0.127/axis-media/media.amp latency=0 ! decodebin ! autovideosink

and it work fine.

I want to control it with a gui in pygtk so I use the gstreamer python bindings. I've wrote this piece of code:

[...]
self.player = gst.Pipeline("player")
source = gst.element_factory_make("rtspsrc", "source")
source.set_property("location", "rtsp://192.168.0.127/axis-media/media.amp")
decoder = gst.element_factory_make("decodebin", "decoder")
sink = gst.element_factory_make("autovideosink", "sink")

self.player.add(source, decoder, sink)
gst.element_link_many(source, decoder, sink)

bus = self.player.get_bus()
bus.add_signal_watch()
bus.enable_sync_message_emission()
bus.connect("message", self.on_message)
bus.connect("sync-message::element", self.on_sync_message)
[...]

But it doesn't work and quit with this message:

gst.element_link_many(source, decoder,sink)
gst.LinkError: failed to link source with decoder


I've also try to improve my CLI with this as I only use h264:

gst-launch-0.10 -v rtspsrc location=rtsp://192.168.0.127/axis-media/media.amp ! rtph264depay !  ffdec_h264 ! xvimagesink

And implement it in my python code like that:

[...]
self.player = gst.Pipeline("player")
source = gst.element_factory_make("rtspsrc", "source")
depay = gst.element_factory_make("rtph264depay", "depay")
decoder = gst.element_factory_make("ffdec_h264", "decoder")
sink = gst.element_factory_make("xvimagesink", "output")

self.player.add(source, depay, decoder, sink)
gst.element_link_many(source, depay, decoder, sink)
[...]

But I got the same error :(
gst.LinkError: failed to link source with depay
There is something wrong between my source (rtspsrc), as it work with decodebin with a filesrc (don't work of course with rtph264depay)

I don't understand why it doesn't work because it work in cli. Any experts of gstreamer who can help me ?

Thanks in advance.

Regards,

------------------------------------------------------------------------------
Beautiful is writing same markup. Internet Explorer 9 supports
standards for HTML5, CSS3, SVG 1.1,  ECMAScript5, and DOM L2 & L3.
Spend less time writing and  rewriting code and more time creating great
experiences on the web. Be a part of the beta today
http://p.sf.net/sfu/msIE9-sfdev2dev
_______________________________________________
gstreamer-devel mailing list
[hidden email]
https://lists.sourceforge.net/lists/listinfo/gstreamer-devel

[Sandino Flores Moreno]

Some pads are created on demand, that's why you cannot connect some
elements in advance.

An easier approach is to use gst.parse_launch(pipeline_desc_string)

###<<
pipeline = gst.parse_launch("rtspsrc name=source latency=0 ! decodebin
! autovideosink")
source = pipeline.get_by_name("source")
source.props.location =  "rtsp://192.168.0.127/axis-media/media.amp"
###>>

On Tue, Nov 16, 2010 at 5:28 AM, lonkaji <[hidden email]> wrote:

> Hi,
>
> I use gstreamer for playing RTSP stream from IP cameras like Axis. I use a
> command line like this:
>
> gst-launch-0.10 rtspsrc location=rtsp://192.168.0.127/axis-media/media.amp
> latency=0 ! decodebin ! autovideosink
>
> and it work fine.
>
> I want to control it with a gui in pygtk so I use the gstreamer python
> bindings. I've wrote this piece of code:
>
> [...]
> self.player = gst.Pipeline("player")
> source = gst.element_factory_make("rtspsrc", "source")
> source.set_property("location", "rtsp://192.168.0.127/axis-media/media.amp")
> decoder = gst.element_factory_make("decodebin", "decoder")
> sink = gst.element_factory_make("autovideosink", "sink")
>
> self.player.add(source, decoder, sink)
> gst.element_link_many(source, decoder, sink)
>
> bus = self.player.get_bus()
> bus.add_signal_watch()
> bus.enable_sync_message_emission()
> bus.connect("message", self.on_message)
> bus.connect("sync-message::element", self.on_sync_message)
> [...]
>
> But it doesn't work and quit with this message:
>
> gst.element_link_many(source, decoder,sink)
> gst.LinkError: failed to link source with decoder
>
>
> I've also try to improve my CLI with this as I only use h264:
>
> gst-launch-0.10 -v rtspsrc
> location=rtsp://192.168.0.127/axis-media/media.amp ! rtph264depay !
> ffdec_h264 ! xvimagesink
>
> And implement it in my python code like that:
>
> [...]
> self.player = gst.Pipeline("player")
> source = gst.element_factory_make("rtspsrc", "source")
> depay = gst.element_factory_make("rtph264depay", "depay")
> decoder = gst.element_factory_make("ffdec_h264", "decoder")
> sink = gst.element_factory_make("xvimagesink", "output")
>
> self.player.add(source, depay, decoder, sink)
> gst.element_link_many(source, depay, decoder, sink)
> [...]
>
> But I got the same error :(
> gst.LinkError: failed to link source with depay
> There is something wrong between my source (rtspsrc), as it work with
> decodebin with a filesrc (don't work of course with rtph264depay)
>
> I don't understand why it doesn't work because it work in cli. Any experts
> of gstreamer who can help me ?
>
> Thanks in advance.
>
> Regards,
>
> ------------------------------------------------------------------------------
> Beautiful is writing same markup. Internet Explorer 9 supports
> standards for HTML5, CSS3, SVG 1.1,  ECMAScript5, and DOM L2 & L3.
> Spend less time writing and  rewriting code and more time creating great
> experiences on the web. Be a part of the beta today
> http://p.sf.net/sfu/msIE9-sfdev2dev
> _______________________________________________
> gstreamer-devel mailing list
> [hidden email]
> https://lists.sourceforge.net/lists/listinfo/gstreamer-devel
>
>

------------------------------------------------------------------------------
Beautiful is writing same markup. Internet Explorer 9 supports
standards for HTML5, CSS3, SVG 1.1,  ECMAScript5, and DOM L2 & L3.
Spend less time writing and  rewriting code and more time creating great
experiences on the web. Be a part of the beta today
http://p.sf.net/sfu/msIE9-sfdev2dev
_______________________________________________
gstreamer-devel mailing list
[hidden email]
https://lists.sourceforge.net/lists/listinfo/gstreamer-devel