gstreamer/subprojects/gst-plugins-base/gst-libs/gst/rtp
Mathieu Duponchelle 6b6ea3c1a6 rtpbasepayload: always store input buffer meta before negotiation
The decision to store the input buffer depends on whether extensions
are to be added to the output buffer, I assume as an optimization.

This creates an issue for subclasses that call negotiate(), where
header_exts is actually populated, from their handle_buffer()
implementation: at chain time, no header extension has been negotiated
yet, which means that we don't add extensions to the first batch of
buffers that comes out.

Keep track of whether negotiate has been called (this is different
from the negotiated field) and always store the input buffer until
then. This fixes the issue while largely preserving the optimization.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/2321>
2022-04-28 10:58:37 +00:00
..
gstrtcpbuffer.c
gstrtcpbuffer.h
gstrtpbaseaudiopayload.c
gstrtpbaseaudiopayload.h
gstrtpbasedepayload.c
gstrtpbasedepayload.h
gstrtpbasepayload.c rtpbasepayload: always store input buffer meta before negotiation 2022-04-28 10:58:37 +00:00
gstrtpbasepayload.h
gstrtpbuffer.c rtpbuffer: The out args for rtp extension data are optional 2022-03-18 10:22:57 +00:00
gstrtpbuffer.h
gstrtpdefs.h
gstrtphdrext.c rtphdrext: Return non-floating references from gst_rtp_header_extension_create_from_uri() 2022-01-27 14:43:41 +00:00
gstrtphdrext.h rtphdrext: increase GstRTPHeaderExtensionClass padding to LARGE 2022-01-19 05:41:40 +00:00
gstrtpmeta.c
gstrtpmeta.h
gstrtppayloads.c
gstrtppayloads.h
meson.build gst-plugins-base: define G_LOG_DOMAIN for all libraries 2021-10-19 00:12:25 +00:00
README
rtp-prelude.h
rtp.h

The RTP libraries
---------------------

  RTP Buffers
  -----------
  The real time protocol as described in RFC 3550 requires the use of special
  packets containing an additional RTP header of at least 12 bytes. GStreamer
  provides some helper functions for creating and parsing these RTP headers.
  The result is a normal #GstBuffer with an additional RTP header.
 
  RTP buffers are usually created with gst_rtp_buffer_new_allocate() or
  gst_rtp_buffer_new_allocate_len(). These functions create buffers with a
  preallocated space of memory. It will also ensure that enough memory
  is allocated for the RTP header. The first function is used when the payload
  size is known. gst_rtp_buffer_new_allocate_len() should be used when the size
  of the whole RTP buffer (RTP header + payload) is known.
 
  When receiving RTP buffers from a network, gst_rtp_buffer_new_take_data()
  should be used when the user would like to parse that RTP packet. (TODO Ask
  Wim what the real purpose of this function is as it seems to simply create a
  duplicate GstBuffer with the same data as the previous one). The
  function will create a new RTP buffer with the given data as the whole RTP
  packet. Alternatively, gst_rtp_buffer_new_copy_data() can be used if the user
  wishes to make a copy of the data before using it in the new RTP buffer.
 
  It is now possible to use all the gst_rtp_buffer_get_*() or
  gst_rtp_buffer_set_*() functions to read or write the different parts of the
  RTP header such as the payload type, the sequence number or the RTP
  timestamp. The use can also retrieve a pointer to the actual RTP payload data
  using the gst_rtp_buffer_get_payload() function.

  RTP Base Payloader Class (GstBaseRTPPayload)
  --------------------------------------------

  All RTP payloader elements (audio or video) should derive from this class.

  RTP Base Audio Payloader Class (GstBaseRTPAudioPayload)
  -------------------------------------------------------

  This base class can be tested through it's children classes. Here is an
  example using the iLBC payloader (frame based).

  For 20ms mode :

  GST_DEBUG="basertpaudiopayload:5" gst-launch-1.0 fakesrc sizetype=2
  sizemax=114 datarate=1900 ! audio/x-iLBC, mode=20 !  rtpilbcpay
  max-ptime="40000000" ! fakesink

  For 30ms mode :

  GST_DEBUG="basertpaudiopayload:5" gst-launch-1.0 fakesrc sizetype=2
  sizemax=150 datarate=1662 ! audio/x-iLBC, mode=30 !  rtpilbcpay
  max-ptime="60000000" ! fakesink

  Here is an example using the uLaw payloader (sample based).

  GST_DEBUG="basertpaudiopayload:5" gst-launch-1.0 fakesrc sizetype=2
  sizemax=150 datarate=8000 ! audio/x-mulaw ! rtppcmupay max-ptime="6000000" !
  fakesink

  RTP Base Depayloader Class (GstBaseRTPDepayload)
  ------------------------------------------------

  All RTP depayloader elements (audio or video) should derive from this class.