Hi, thank's for the tips. When I told that I've started from GstPluginTemplate I mean something like this: GST_BOILERPLATE (GstPluginTemplate, gst_plugin_template, GstBaseSrc,     GST_TYPE_ELEMENT); Is it what did you mean? <div>2007/6/28, René Stadler <<a href="mailto:mail@renestadler.de">mail@renestadler.de</a>>:<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> Am Donnerstag, den 28.06.2007, 13:09 +0200 schrieb Riccardo Corona: > Hi, > I'm writing a source plugin, I'm started from GstPluginTemplate to > make a simple plugin that generate only B&W frames... > The problem is that with this pipeline: > I strongly suggest deriving from GstBaseSrc instead. > mysrc ! ffmpegcolorspace ! directdrawsink > > the pipeline is blocked on PREROLLING and in debug mode I can see that > the last state of my plugin is PAUSED. > Here the snipped of code in which I set the buffer: > > > > /* get_range function >  * makes it a source of a stream >  */ > static gboolean gst_plugin_template_get_range (GstPad *pad, guint64 > offset, guint lenght, GstBuffer **buf) > { >     static  gboolean white=1; > >     GstPluginTemplate *plug= GST_PLUGIN_TEMPLATE (GST_OBJECT_PARENT > (pad) ); > >      GstBuffer *buffer; >       gint size, width, height, bpp; >       width = 320; height = 240; bpp = 16; >       size = width * height * bpp; >       buffer = gst_buffer_new(); >       GST_BUFFER_SIZE (buffer) = size; > >     if (white)GST_BUFFER_MALLOCDATA (buffer) =  g_memdup (0xff,size); >         else GST_BUFFER_MALLOCDATA (buffer) =  g_memdup (0x0,size); > >     white=!white; > >       GST_BUFFER_DATA (buffer) = GST_BUFFER_MALLOCDATA (buffer); > > >     ts = gst_util_uint64_scale_int (frame_num * GST_SECOND, FPS_DEN, > FPS_NUM); >     next_ts = gst_util_uint64_scale_int ((frame_num + 1) * GST_SECOND, > FPS_DEN,  FPS_NUM); > >     GST_BUFFER_TIMESTAMP (buffer) = ts; >     GST_BUFFER_DURATION (buffer) = next_ts-ts; > >     frame_num++; > > >     return gst_pad_push (plug->srcpad, buffer); > > } > This is completely wrong.  In a get_range function, you are supposed to return the buffer to the supplied location!  Take a look at gstreamer/docs/design/part-scheduling.txt [1] and other docs in that directory to get some insight. [1]: <a href="http://webcvs.freedesktop.org/gstreamer/gstreamer/docs/design/part-scheduling.txt?view=markup">http://webcvs.freedesktop.org/gstreamer/gstreamer/docs/design/part-scheduling.txt?view=markup </a> > > I thought that setting the timestamp is enough to have continuosly a > stream of images but it seems that I'm wrong. > Do I must force the state of the plugin in PLAY mode? > Or maybe I'm wrong with the buffer management? > > Any help will be very appreciate becouse I'm new to plugin writing... > > > Best Regards. > > > > -- > Riccardo Corona -- Regards,   René Stadler </blockquote></div> -- Riccardo Corona