<div dir="ltr">Thanks Nirbheek. Your answer is exactly what I am looking for. Really appreciate it. <div> </div><div>Jake</div></div><div class="gmail_extra"> <div class="gmail_quote">On Mon, Sep 5, 2016 at 11:25 PM, Nirbheek Chauhan <<a href="mailto:nirbheek.chauhan@gmail.com" target="_blank">nirbheek.chauhan@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On Tue, Sep 6, 2016 at 5:21 AM, Jake Zhang <<a href="mailto:zjpseudo@gmail.com">zjpseudo@gmail.com</a>> wrote: > I am implementing a fairly complicate custom plugin and this plugin > sometimes will hold on some input buffers by pushing them into a queue if > some timestamp condition does not meet yet, and sometimes it might push more > than one buffer to srcpads if certain condition is met. Do you guys see any > issue of doing this? I just want to make sure I will not have a big issue > with this unconventional chain function. > > I have went through the gstpad.c source code, and if my understanding is > correctly the pad chain function will be called once every time each time > there is a input buffer. And I do not see any issue with my above > implementation. > > Please correct me if I am wrong. Any input is appropriated. > Yes, it is a very common use-case to not always push a single buffer when chaining a buffer. All you have to do is make sure that you return GST_FLOW_OK when everything is fine. You can either push nothing, a single buffer, or multiple buffers, or a buffer list. There's roughly three things you can do here, depending on what your data looks like. If your data is meant to be concatenated/merged, then you can merge the contents of buffers and push them as a single buffer as needed. One way to do this is with GstAdapter[1]. This is commonly done in, for instance, payloaders and depayloaders. 1. <a href="https://developer.gnome.org/gstreamer-libs/stable/GstAdapter.html" rel="noreferrer" target="_blank">https://developer.gnome.org/gstreamer-libs/stable/GstAdapter.html</a> If you want to keep GstBuffers as they are, you can maintain a GList or GPtrArray of them and push multiple ones individually (gst_pad_push) in a single chain function invocation (be careful to do error checking for each push!). The third option is to both store and push them as a single GstBufferList[2] (gst_pad_push_list). 2. <a href="https://developer.gnome.org/gstreamer/stable/gstreamer-GstBufferList.html" rel="noreferrer" target="_blank">https://developer.gnome.org/gstreamer/stable/gstreamer-GstBufferList.html</a> The first and third options have the least overhead, if that matters for your use-case. Cheers, Nirbheek -- ~Nirbheek Chauhan _______________________________________________ gstreamer-devel mailing list <a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a> <a href="https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" rel="noreferrer" target="_blank">https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a> </blockquote></div> </div>