A function that will be called on sinkpads when chaining buffers.
The function typically processes the data contained in the buffer and
either consumes the data or passes it on to the internally linked pad(s).
The implementer of this function receives a refcount to buffer and should
gst_buffer_unref() when the buffer is no longer needed.
When a chain function detects an error in the data stream, it must post an
error on the bus and return an appropriate #GstFlowReturn value.
A function that will be called on sinkpads when chaining buffers. The function typically processes the data contained in the buffer and either consumes the data or passes it on to the internally linked pad(s). The implementer of this function receives a refcount to
bufferand should gst_buffer_unref() when the buffer is no longer needed. When a chain function detects an error in the data stream, it must post an error on the bus and return an appropriate #GstFlowReturn value.