rtp: add SMPTE 336M KLV metadata payloader

http://tools.ietf.org/html/rfc6597

gst/rtp/Makefile.am

@@ -50,6 +50,7 @@ libgstrtp_la_SOURCES = \
 	gstrtpj2kpay.c \
 	gstrtpjpegdepay.c \
 	gstrtpjpegpay.c \
+	gstrtpklvpay.c \
 	gstrtpL16depay.c \
 	gstrtpL16pay.c \
 	gstrtpL24depay.c \
@@ -153,6 +154,7 @@ noinst_HEADERS =			\
 	gstrtpj2kpay.h \
 	gstrtpjpegdepay.h \
 	gstrtpjpegpay.h \
+	gstrtpklvpay.h \
 	gstrtpmp1sdepay.h \
 	gstrtpmp2tdepay.h \
 	gstrtpmp2tpay.h \

gst/rtp/gstrtp.c

@@ -68,6 +68,7 @@
 #include "gstrtpj2kpay.h"
 #include "gstrtpjpegdepay.h"
 #include "gstrtpjpegpay.h"
+#include "gstrtpklvpay.h"
 #include "gstrtpL16depay.h"
 #include "gstrtpL16pay.h"
 #include "gstrtpL24depay.h"
@@ -242,6 +243,9 @@ plugin_init (GstPlugin * plugin)
   if (!gst_rtp_jpeg_pay_plugin_init (plugin))
     return FALSE;
 
+  if (!gst_rtp_klv_pay_plugin_init (plugin))
+    return FALSE;
+
   if (!gst_rtp_L16_pay_plugin_init (plugin))
     return FALSE;
 

gst/rtp/gstrtpklvpay.c

@@ -0,0 +1,203 @@
+/* GStreamer RTP KLV Payloader
+ * Copyright (C) 2014-2015 Tim-Philipp Müller <tim@centricular.com>>
+ * Copyright (C) 2014-2015 Centricular Ltd
+ *
+ * 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., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+/**
+ * SECTION:element-rtpklvpay
+ * @see_also: rtpklvdepay
+ *
+ * Payloads KLV metadata into RTP packets according to RFC 6597.
+ * For detailed information see: http://tools.ietf.org/html/rfc6597
+ *
+ * <refsect2>
+ * <title>Example pipeline</title>
+ * |[
+ * gst-launch-1.0 filesrc location=video-with-klv.ts ! tsdemux ! rtpklvpay ! udpsink
+ * ]| This example pipeline will payload an RTP KLV stream extracted from an
+ * MPEG-TS stream and send it via UDP to an RTP receiver.
+ * </refsect2>
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gstrtpklvpay.h"
+
+#include <string.h>
+
+GST_DEBUG_CATEGORY_STATIC (klvpay_debug);
+#define GST_CAT_DEFAULT (klvpay_debug)
+
+static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
+    GST_PAD_SRC,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS ("application/x-rtp, "
+        "media = (string) application, clock-rate = (int) [1, MAX], "
+        "encoding-name = (string) SMPTE336M")
+    );
+
+static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
+    GST_PAD_SINK,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS ("meta/x-klv, parsed = (bool) true"));
+
+#define gst_rtp_klv_pay_parent_class parent_class
+G_DEFINE_TYPE (GstRtpKlvPay, gst_rtp_klv_pay, GST_TYPE_RTP_BASE_PAYLOAD);
+
+static gboolean gst_rtp_klv_pay_setcaps (GstRTPBasePayload * pay,
+    GstCaps * caps);
+static GstFlowReturn gst_rtp_klv_pay_handle_buffer (GstRTPBasePayload * pay,
+    GstBuffer * buf);
+
+static void
+gst_rtp_klv_pay_class_init (GstRtpKlvPayClass * klass)
+{
+  GstElementClass *element_class = (GstElementClass *) klass;
+  GstRTPBasePayloadClass *rtpbasepay_class;
+
+  GST_DEBUG_CATEGORY_INIT (klvpay_debug, "klvpay", 0, "RTP KLV Payloader");
+
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&src_template));
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&sink_template));
+
+  gst_element_class_set_static_metadata (element_class,
+      "RTP KLV Payloader", "Codec/Payloader/Network",
+      "Payloads KLV (SMPTE ST 336) metadata as RTP packets",
+      "Tim-Philipp Müller <tim@centricular.com>");
+
+  rtpbasepay_class = (GstRTPBasePayloadClass *) klass;
+
+  rtpbasepay_class->set_caps = gst_rtp_klv_pay_setcaps;
+  rtpbasepay_class->handle_buffer = gst_rtp_klv_pay_handle_buffer;
+}
+
+static void
+gst_rtp_klv_pay_init (GstRtpKlvPay * klvpay)
+{
+  /* nothing to do here yet */
+}
+
+static gboolean
+gst_rtp_klv_pay_setcaps (GstRTPBasePayload * pay, GstCaps * caps)
+{
+  /* FIXME: allow other clock rates */
+  gst_rtp_base_payload_set_options (pay, "application", TRUE, "SMPTE336M",
+      90000);
+
+  return gst_rtp_base_payload_set_outcaps (pay, NULL);
+}
+
+static GstFlowReturn
+gst_rtp_klv_pay_handle_buffer (GstRTPBasePayload * basepayload, GstBuffer * buf)
+{
+  GstFlowReturn ret = GST_FLOW_OK;
+  GstBufferList *list = NULL;
+  GstRtpKlvPay *pay;
+  GstMapInfo map;
+  GstBuffer *outbuf = NULL;
+  gsize offset;
+  guint mtu, rtp_header_size, max_payload_size;
+
+  pay = GST_RTP_KLV_PAY (basepayload);
+  mtu = GST_RTP_BASE_PAYLOAD_MTU (basepayload);
+
+  rtp_header_size = gst_rtp_buffer_calc_header_len (0);
+  max_payload_size = mtu - rtp_header_size;
+
+  gst_buffer_map (buf, &map, GST_MAP_READ);
+
+  if (map.size == 0)
+    goto done;
+
+  /* KLV coding shall use and only use a fixed 16-byte SMPTE-administered
+   * Universal Label, according to SMPTE 298M as Key (Rec. ITU R-BT.1653-1) */
+  if (map.size < 16 || GST_READ_UINT32_BE (map.data) != 0x060E2B34)
+    goto bad_input;
+
+  if (map.size > max_payload_size)
+    list = gst_buffer_list_new ();
+
+  GST_LOG_OBJECT (pay, "%" G_GSIZE_FORMAT " bytes of data to payload",
+      map.size);
+
+  offset = 0;
+  while (offset < map.size) {
+    GstBuffer *payloadbuf;
+    GstRTPBuffer rtp = { NULL };
+    guint payload_size;
+    guint bytes_left;
+
+    bytes_left = map.size - offset;
+    payload_size = MIN (bytes_left, max_payload_size);
+
+    outbuf = gst_rtp_buffer_new_allocate (0, 0, 0);
+
+    if (payload_size == bytes_left) {
+      GST_LOG_OBJECT (pay, "last packet of KLV unit");
+      gst_rtp_buffer_map (outbuf, GST_MAP_WRITE, &rtp);
+      gst_rtp_buffer_set_marker (&rtp, 1);
+      gst_rtp_buffer_unmap (&rtp);
+    }
+
+    GST_LOG_OBJECT (pay, "packet with payload size %u", payload_size);
+
+    payloadbuf = gst_buffer_copy_region (buf, GST_BUFFER_COPY_MEMORY,
+        offset, payload_size);
+
+    /* join rtp header + payload memory parts */
+    outbuf = gst_buffer_append (outbuf, payloadbuf);
+
+    GST_BUFFER_PTS (outbuf) = GST_BUFFER_PTS (buf);
+    GST_BUFFER_DTS (outbuf) = GST_BUFFER_DTS (buf);
+
+    /* and add to list */
+    if (list != NULL)
+      gst_buffer_list_insert (list, -1, outbuf);
+
+    offset += payload_size;
+  }
+
+done:
+
+  gst_buffer_unmap (buf, &map);
+  gst_buffer_unref (buf);
+
+  if (list != NULL)
+    ret = gst_rtp_base_payload_push_list (basepayload, list);
+  else if (outbuf != NULL)
+    ret = gst_rtp_base_payload_push (basepayload, outbuf);
+
+  return ret;
+
+/* ERRORS */
+bad_input:
+  {
+    GST_ERROR_OBJECT (pay, "Input doesn't look like a KLV packet, ignoring");
+    goto done;
+  }
+}
+
+gboolean
+gst_rtp_klv_pay_plugin_init (GstPlugin * plugin)
+{
+  return gst_element_register (plugin, "rtpklvpay",
+      GST_RANK_SECONDARY, GST_TYPE_RTP_KLV_PAY);
+}

gst/rtp/gstrtpklvpay.h

@@ -0,0 +1,60 @@
+/* GStreamer RTP KLV Payloader
+ * Copyright (C) 2014-2015 Tim-Philipp Müller <tim@centricular.com>>
+ * Copyright (C) 2014-2015 Centricular Ltd
+ *
+ * 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., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __GST_RTP_KLV_PAY_H__
+#define __GST_RTP_KLV_PAY_H__
+
+#include <gst/gst.h>
+#include <gst/base/gstadapter.h>
+#include <gst/rtp/rtp.h>
+
+G_BEGIN_DECLS
+
+#define GST_TYPE_RTP_KLV_PAY \
+  (gst_rtp_klv_pay_get_type())
+#define GST_RTP_KLV_PAY(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_RTP_KLV_PAY,GstRtpKlvPay))
+#define GST_RTP_KLV_PAY_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_RTP_KLV_PAY,GstRtpKlvPayClass))
+#define GST_IS_RTP_KLV_PAY(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_RTP_KLV_PAY))
+#define GST_IS_RTP_KLV_PAY_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_RTP_KLV_PAY))
+
+typedef struct _GstRtpKlvPay GstRtpKlvPay;
+typedef struct _GstRtpKlvPayClass GstRtpKlvPayClass;
+
+struct _GstRtpKlvPay
+{
+  GstRTPBasePayload rtpbasepayload;
+};
+
+struct _GstRtpKlvPayClass
+{
+  GstRTPBasePayloadClass rtpbasepayload_class;
+};
+
+G_GNUC_INTERNAL  GType     gst_rtp_klv_pay_get_type (void);
+
+G_GNUC_INTERNAL  gboolean  gst_rtp_klv_pay_plugin_init (GstPlugin * plugin);
+
+G_END_DECLS
+
+#endif /* __GST_RTP_KLV_PAY_H__ */