Correspondence between appsrc input and appsink output buffers

[benjamin.hepp at posteo.de]

On 09.11.2016 08:49, Sebastian Dröge wrote:

> That's generally not a good idea and should cause crashes or other
> problems over time. You always have to do the reference counting
> correct.

Of course, after decreasing the ref count to 1 and adding the GstMeta to 
the buffer one has to increase the ref count to the previous value.

> If a buffer is not writable, you need to copy it (the buffer, not the
> actual memory inside it). See gst_buffer_make_writable() for automating
> that task.

I don't see how that can work for the GstMeta transformation function:
***_meta_transform (GstBuffer * transbuf, GstMeta * meta,
     GstBuffer * buffer, GQuark type, gpointer data)

You can very well copy the transbuf buffer and add the GstMeta to the 
copy but then how could you replace transbuf with it?