gstreamer/gst/rtp/gstrtph261depay.c
Sebastian Dröge b1089fb520 rtp: Copy metadata in the (de)payloader, but only the relevant ones
The payloader didn't copy anything so far, the depayloader copied every
possible meta. Let's make it consistent and just copy all metas without
tags or with only the video tag.

https://bugzilla.gnome.org/show_bug.cgi?id=751774
2015-08-11 12:47:23 +02:00

295 lines
8.8 KiB
C

/* GStreamer
*
* Copyright (C) <2014> Stian Selnes <stian@pexip.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:element-rtph261depay
* @see_also: rtph261pay
*
* Extract encoded H.261 video frames from RTP packets according to RFC 4587.
* For detailed information see: https://www.rfc-editor.org/rfc/rfc4587.txt
*
* The depayloader takes an RTP packet and extracts its H.261 stream. It
* aggregates the extracted stream until a complete frame is received before
* it pushes it downstream.
*
* <refsect2>
* <title>Example pipeline</title>
* |[
* gst-launch-1.0 udpsrc caps='application/x-rtp, payload=31' ! rtph261depay ! avdec_h261 ! autovideosink
* ]| This example pipeline will depayload and decode an RTP H.261 video stream.
* Refer to the rtph261pay example to create the RTP stream.
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <string.h>
#include <gst/rtp/gstrtpbuffer.h>
#include <gst/video/video.h>
#include "gstrtph261depay.h"
#include "gstrtph261pay.h" /* GstRtpH261PayHeader */
#include "gstrtputils.h"
GST_DEBUG_CATEGORY_STATIC (rtph261depay_debug);
#define GST_CAT_DEFAULT (rtph261depay_debug)
static const guint8 NO_LEFTOVER = 0xFF;
static GstStaticPadTemplate gst_rtp_h261_depay_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("video/x-h261")
);
static GstStaticPadTemplate gst_rtp_h261_depay_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-rtp, "
"media = (string) \"video\", "
"payload = (int) " GST_RTP_PAYLOAD_H261_STRING ", "
"clock-rate = (int) 90000, " "encoding-name = (string) \"H261\"; "
"application/x-rtp, "
"media = (string) \"video\", "
"payload = (int) " GST_RTP_PAYLOAD_DYNAMIC_STRING ", "
"clock-rate = (int) 90000, " "encoding-name = (string) \"H261\"")
);
G_DEFINE_TYPE (GstRtpH261Depay, gst_rtp_h261_depay,
GST_TYPE_RTP_BASE_DEPAYLOAD);
#define parent_class gst_rtp_h261_depay_parent_class
static GstBuffer *
gst_rtp_h261_depay_process (GstRTPBaseDepayload * depayload, GstRTPBuffer * rtp)
{
GstRtpH261Depay *depay;
GstBuffer *outbuf = NULL;
gint payload_len;
guint8 *payload;
const guint header_len = GST_RTP_H261_PAYLOAD_HEADER_LEN;
gboolean marker;
GstRtpH261PayHeader *header;
depay = GST_RTP_H261_DEPAY (depayload);
if (GST_BUFFER_IS_DISCONT (rtp->buffer)) {
GST_DEBUG_OBJECT (depay, "Discont buffer, flushing adapter");
gst_adapter_clear (depay->adapter);
depay->leftover = NO_LEFTOVER;
depay->start = FALSE;
}
payload_len = gst_rtp_buffer_get_payload_len (rtp);
payload = gst_rtp_buffer_get_payload (rtp);
marker = gst_rtp_buffer_get_marker (rtp);
if (payload_len < 4) {
GST_WARNING_OBJECT (depay,
"Dropping packet with payload length invalid length");
return NULL;
}
header = (GstRtpH261PayHeader *) payload;
GST_DEBUG_OBJECT (depay,
"payload_len: %d, header_len: %d, sbit: %d, ebit: %d, marker %d",
payload_len, header_len, header->sbit, header->ebit, marker);
payload += header_len;
payload_len -= header_len;
if (!depay->start) {
/* Check for picture start code */
guint32 bits = GST_READ_UINT32_BE (payload) << header->sbit;
if (payload_len > 4 && bits >> 12 == 0x10) {
GST_DEBUG_OBJECT (depay, "Found picture start code");
depay->start = TRUE;
} else {
GST_DEBUG_OBJECT (depay, "No picture start code yet, skipping payload");
goto skip;
}
}
if (header->sbit != 0) {
/* Take the leftover from previous packet and merge it at the beginning */
payload[0] &= 0xFF >> header->sbit;
if (depay->leftover != NO_LEFTOVER) {
/* Happens if sbit is set for first packet in frame. Then previous byte
* has already been flushed. */
payload[0] |= depay->leftover;
}
depay->leftover = NO_LEFTOVER;
}
if (header->ebit == 0) {
/* H.261 stream ends on byte boundary, take entire packet */
gst_adapter_push (depay->adapter,
gst_rtp_buffer_get_payload_subbuffer (rtp, header_len, payload_len));
} else {
/* Take the entire buffer except for the last byte, which will be kept to
* merge with next packet */
gst_adapter_push (depay->adapter,
gst_rtp_buffer_get_payload_subbuffer (rtp, header_len,
payload_len - 1));
depay->leftover = payload[payload_len - 1] & (0xFF << header->ebit);
}
skip:
if (marker) {
if (depay->start) {
guint avail;
if (depay->leftover != NO_LEFTOVER) {
GstBuffer *buf = gst_buffer_new_and_alloc (1);
gst_buffer_memset (buf, 0, depay->leftover, 1);
gst_adapter_push (depay->adapter, buf);
depay->leftover = NO_LEFTOVER;
}
avail = gst_adapter_available (depay->adapter);
outbuf = gst_adapter_take_buffer (depay->adapter, avail);
gst_rtp_drop_meta (GST_ELEMENT_CAST (depay), outbuf,
g_quark_from_static_string (GST_META_TAG_VIDEO_STR));
/* Note that the I flag does not mean intra frame, but that the entire
* stream is intra coded. */
if (header->i)
GST_BUFFER_FLAG_UNSET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT);
else
GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT);
GST_DEBUG_OBJECT (depay, "Pushing out a buffer of %u bytes", avail);
depay->start = FALSE;
} else {
depay->start = TRUE;
}
}
return outbuf;
}
static gboolean
gst_rtp_h261_depay_setcaps (GstRTPBaseDepayload * filter, GstCaps * caps)
{
GstCaps *srccaps;
srccaps = gst_caps_new_empty_simple ("video/x-h261");
gst_pad_set_caps (GST_RTP_BASE_DEPAYLOAD_SRCPAD (filter), srccaps);
gst_caps_unref (srccaps);
return TRUE;
}
static GstStateChangeReturn
gst_rtp_h261_depay_change_state (GstElement * element,
GstStateChange transition)
{
GstRtpH261Depay *depay;
GstStateChangeReturn ret;
depay = GST_RTP_H261_DEPAY (element);
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
break;
case GST_STATE_CHANGE_READY_TO_PAUSED:
gst_adapter_clear (depay->adapter);
depay->start = FALSE;
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_READY_TO_NULL:
break;
default:
break;
}
return ret;
}
static void
gst_rtp_h261_depay_dispose (GObject * object)
{
GstRtpH261Depay *depay;
depay = GST_RTP_H261_DEPAY (object);
if (depay->adapter) {
gst_object_unref (depay->adapter);
depay->adapter = NULL;
}
G_OBJECT_CLASS (parent_class)->dispose (object);
}
static void
gst_rtp_h261_depay_class_init (GstRtpH261DepayClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
GstRTPBaseDepayloadClass *gstrtpbasedepayload_class;
gobject_class = G_OBJECT_CLASS (klass);
gstelement_class = GST_ELEMENT_CLASS (klass);
gstrtpbasedepayload_class = GST_RTP_BASE_DEPAYLOAD_CLASS (klass);
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&gst_rtp_h261_depay_src_template));
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&gst_rtp_h261_depay_sink_template));
gst_element_class_set_static_metadata (gstelement_class,
"RTP H261 depayloader", "Codec/Depayloader/Network/RTP",
"Extracts H261 video from RTP packets (RFC 4587)",
"Stian Selnes <stian@pexip.com>");
gstrtpbasedepayload_class->process_rtp_packet = gst_rtp_h261_depay_process;
gstrtpbasedepayload_class->set_caps = gst_rtp_h261_depay_setcaps;
gobject_class->dispose = gst_rtp_h261_depay_dispose;
gstelement_class->change_state = gst_rtp_h261_depay_change_state;
GST_DEBUG_CATEGORY_INIT (rtph261depay_debug, "rtph261depay", 0,
"H261 Video RTP Depayloader");
}
static void
gst_rtp_h261_depay_init (GstRtpH261Depay * depay)
{
depay->adapter = gst_adapter_new ();
depay->leftover = NO_LEFTOVER;
}
gboolean
gst_rtp_h261_depay_plugin_init (GstPlugin * plugin)
{
return gst_element_register (plugin, "rtph261depay",
GST_RANK_SECONDARY, GST_TYPE_RTP_H261_DEPAY);
}