--- /dev/null
+/* GStreamer RTP KLV Depayloader
+ * 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-rtpklvdepay
+ * @see_also: rtpklvpay
+ *
+ * Extract KLV metadata from 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 udpsrc caps='application/x-rtp, media=(string)application, clock-rate=(int)90000, encoding-name=(string)SMPTE336M' ! rtpklvdepay ! fakesink dump=true
+ * ]| This example pipeline will depayload an RTP KLV stream and display
+ * a hexdump of the KLV data on stdout.
+ * </refsect2>
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gstrtpklvdepay.h"
+
+#include <string.h>
+
+GST_DEBUG_CATEGORY_STATIC (klvdepay_debug);
+#define GST_CAT_DEFAULT (klvdepay_debug)
+
+static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
+ GST_PAD_SRC,
+ GST_PAD_ALWAYS,
+ GST_STATIC_CAPS ("meta/x-klv, parsed = (bool) true"));
+
+static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
+ GST_PAD_SINK,
+ GST_PAD_ALWAYS,
+ GST_STATIC_CAPS ("application/x-rtp, "
+ "media = (string) application, clock-rate = (int) [1, MAX], "
+ "encoding-name = (string) SMPTE336M")
+ );
+
+#define gst_rtp_klv_depay_parent_class parent_class
+G_DEFINE_TYPE (GstRtpKlvDepay, gst_rtp_klv_depay, GST_TYPE_RTP_BASE_DEPAYLOAD);
+
+static void gst_rtp_klv_depay_finalize (GObject * object);
+
+static GstStateChangeReturn gst_rtp_klv_depay_change_state (GstElement *
+ element, GstStateChange transition);
+static gboolean gst_rtp_klv_depay_setcaps (GstRTPBaseDepayload * depayload,
+ GstCaps * caps);
+static GstBuffer *gst_rtp_klv_depay_process (GstRTPBaseDepayload * depayload,
+ GstBuffer * buf);
+
+static void gst_rtp_klv_depay_reset (GstRtpKlvDepay * klvdepay);
+
+static void
+gst_rtp_klv_depay_class_init (GstRtpKlvDepayClass * klass)
+{
+ GstElementClass *element_class = (GstElementClass *) klass;
+ GObjectClass *gobject_class = (GObjectClass *) klass;
+ GstRTPBaseDepayloadClass *rtpbasedepayload_class;
+
+ GST_DEBUG_CATEGORY_INIT (klvdepay_debug, "klvdepay", 0,
+ "RTP KLV Depayloader");
+
+ gobject_class->finalize = gst_rtp_klv_depay_finalize;
+
+ element_class->change_state = gst_rtp_klv_depay_change_state;
+
+ 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 Depayloader", "Codec/Depayloader/Network",
+ "Extracts KLV (SMPTE ST 336) metadata from RTP packets",
+ "Tim-Philipp Müller <tim@centricular.com>");
+
+ rtpbasedepayload_class = (GstRTPBaseDepayloadClass *) klass;
+
+ rtpbasedepayload_class->set_caps = gst_rtp_klv_depay_setcaps;
+ rtpbasedepayload_class->process = gst_rtp_klv_depay_process;
+}
+
+static void
+gst_rtp_klv_depay_init (GstRtpKlvDepay * klvdepay)
+{
+ klvdepay->adapter = gst_adapter_new ();
+}
+
+static void
+gst_rtp_klv_depay_finalize (GObject * object)
+{
+ GstRtpKlvDepay *klvdepay;
+
+ klvdepay = GST_RTP_KLV_DEPAY (object);
+
+ gst_rtp_klv_depay_reset (klvdepay);
+ g_object_unref (klvdepay->adapter);
+
+ G_OBJECT_CLASS (parent_class)->finalize (object);
+}
+
+static void
+gst_rtp_klv_depay_reset (GstRtpKlvDepay * klvdepay)
+{
+ GST_DEBUG_OBJECT (klvdepay, "resetting");
+ gst_adapter_clear (klvdepay->adapter);
+ klvdepay->resync = TRUE;
+ klvdepay->last_rtp_ts = -1;
+}
+
+static gboolean
+gst_rtp_klv_depay_setcaps (GstRTPBaseDepayload * depayload, GstCaps * caps)
+{
+ GstStructure *s;
+ GstCaps *src_caps;
+ gboolean res;
+ gint clock_rate;
+
+ s = gst_caps_get_structure (caps, 0);
+
+ if (!gst_structure_get_int (s, "clock-rate", &clock_rate))
+ return FALSE;
+
+ depayload->clock_rate = clock_rate;
+
+ src_caps = gst_static_pad_template_get_caps (&src_template);
+ res = gst_pad_set_caps (GST_RTP_BASE_DEPAYLOAD_SRCPAD (depayload), src_caps);
+ gst_caps_unref (src_caps);
+
+ return res;
+}
+
+static gboolean
+klv_get_vlen (const guint8 * data, guint data_len, guint64 * v_len,
+ gsize * len_size)
+{
+ guint8 first_byte, len_len;
+ guint64 len;
+
+ g_assert (data_len > 0);
+
+ first_byte = *data++;
+
+ if ((first_byte & 0x80) == 0) {
+ *v_len = first_byte & 0x7f;
+ *len_size = 1;
+ return TRUE;
+ }
+
+ len_len = first_byte & 0x7f;
+
+ if (len_len == 0 || len_len > 8)
+ return FALSE;
+
+ if ((1 + len_len) > data_len)
+ return FALSE;
+
+ *len_size = 1 + len_len;
+
+ len = 0;
+ while (len_len > 0) {
+ len = len << 8 | *data++;
+ --len_len;
+ }
+
+ *v_len = len;
+
+ return TRUE;
+}
+
+static GstBuffer *
+gst_rtp_klv_depay_process_data (GstRtpKlvDepay * klvdepay)
+{
+ gsize avail, data_len, len_size;
+ GstBuffer *outbuf;
+ guint8 data[1 + 8];
+ guint64 v_len;
+
+ avail = gst_adapter_available (klvdepay->adapter);
+
+ if (avail == 0)
+ return NULL;
+
+ /* need at least 16 bytes of UL key plus 1 byte of length */
+ if (avail < 16 + 1)
+ goto bad_klv_packet;
+
+ /* check if the declared KLV unit size matches actual bytes available */
+ data_len = MIN (avail - 16, 1 + 8);
+ gst_adapter_copy (klvdepay->adapter, data, 16, data_len);
+ if (!klv_get_vlen (data, data_len, &v_len, &len_size))
+ goto bad_klv_packet;
+
+ if (avail < 16 + len_size + v_len)
+ goto bad_klv_packet;
+
+ outbuf = gst_adapter_take_buffer (klvdepay->adapter, avail);
+
+ /* Mark buffers as key unit to signal this is the start of a KLV unit
+ * (for now all buffers will be flagged like this, since all buffers are
+ * self-contained KLV units, but in future that might change) */
+ outbuf = gst_buffer_make_writable (outbuf);
+ GST_BUFFER_FLAG_UNSET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT);
+
+ return outbuf;
+
+/* ERRORS */
+bad_klv_packet:
+ {
+ GST_WARNING_OBJECT (klvdepay, "bad KLV packet, dropping");
+ gst_rtp_klv_depay_reset (klvdepay);
+ return NULL;
+ }
+}
+
+static GstBuffer *
+gst_rtp_klv_depay_process (GstRTPBaseDepayload * depayload, GstBuffer * buf)
+{
+ GstRtpKlvDepay *klvdepay = GST_RTP_KLV_DEPAY (depayload);
+ GstRTPBuffer rtp = { NULL };
+ GstBuffer *payload, *outbuf = NULL;
+ gboolean marker, start;
+ guint32 rtp_ts;
+ guint payload_len;
+
+ gst_rtp_buffer_map (buf, GST_MAP_READ, &rtp);
+
+ payload_len = gst_rtp_buffer_get_payload_len (&rtp);
+
+ /* marker bit signals last fragment of a KLV unit */
+ marker = gst_rtp_buffer_get_marker (&rtp);
+
+ /* deduce start of new KLV unit in case sender doesn't set marker bits
+ * (it's not like the spec is ambiguous about that, but what can you do) */
+ rtp_ts = gst_rtp_buffer_get_timestamp (&rtp);
+ start = (klvdepay->last_rtp_ts != -1 && klvdepay->last_rtp_ts != rtp_ts);
+
+ klvdepay->last_rtp_ts = rtp_ts;
+
+ /* yet another fallback to deduce start of new KLV unit */
+ if (!marker && !start && payload_len > 16) {
+ const guint8 *data;
+ guint64 v_len;
+ gsize len_size;
+
+ data = gst_rtp_buffer_get_payload (&rtp);
+ if (GST_READ_UINT32_BE (data) == 0x060e2b34 &&
+ klv_get_vlen (data + 16, payload_len - 16, &v_len, &len_size) &&
+ 16 + len_size + v_len == payload_len) {
+ GST_LOG_OBJECT (klvdepay, "Looks like we got a self-contained KLV unit");
+ marker = TRUE;
+ }
+ }
+
+ GST_LOG_OBJECT (klvdepay, "payload of %u bytes, marker=%d, start=%d",
+ payload_len, marker, start);
+
+ if (GST_BUFFER_IS_DISCONT (buf)) {
+ GST_WARNING_OBJECT (klvdepay, "DISCONT, need to resync");
+ gst_rtp_klv_depay_reset (klvdepay);
+ start = FALSE;
+ }
+
+ if (klvdepay->resync && !start) {
+ GST_DEBUG_OBJECT (klvdepay, "Dropping buffer, waiting to resync");
+
+ if (marker)
+ klvdepay->resync = FALSE;
+
+ goto done;
+ }
+
+ if (start && !marker)
+ outbuf = gst_rtp_klv_depay_process_data (klvdepay);
+
+ payload = gst_rtp_buffer_get_payload_buffer (&rtp);
+ gst_adapter_push (klvdepay->adapter, payload);
+
+ if (marker)
+ outbuf = gst_rtp_klv_depay_process_data (klvdepay);
+
+done:
+
+ gst_rtp_buffer_unmap (&rtp);
+
+ return outbuf;
+}
+
+static GstStateChangeReturn
+gst_rtp_klv_depay_change_state (GstElement * element, GstStateChange transition)
+{
+ GstRtpKlvDepay *klvdepay;
+ GstStateChangeReturn ret;
+
+ klvdepay = GST_RTP_KLV_DEPAY (element);
+
+ switch (transition) {
+ case GST_STATE_CHANGE_READY_TO_PAUSED:
+ gst_rtp_klv_depay_reset (klvdepay);
+ break;
+ default:
+ break;
+ }
+
+ ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
+
+ switch (transition) {
+ case GST_STATE_CHANGE_PAUSED_TO_READY:
+ gst_rtp_klv_depay_reset (klvdepay);
+ break;
+ default:
+ break;
+ }
+ return ret;
+}
+
+gboolean
+gst_rtp_klv_depay_plugin_init (GstPlugin * plugin)
+{
+ return gst_element_register (plugin, "rtpklvdepay",
+ GST_RANK_SECONDARY, GST_TYPE_RTP_KLV_DEPAY);
+}
--- /dev/null
+/* GStreamer RTP KLV Depayloader
+ * 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_DEPAY_H__
+#define __GST_RTP_KLV_DEPAY_H__
+
+#include <gst/gst.h>
+#include <gst/base/gstadapter.h>
+#include <gst/rtp/gstrtpbasedepayload.h>
+
+G_BEGIN_DECLS
+
+#define GST_TYPE_RTP_KLV_DEPAY \
+ (gst_rtp_klv_depay_get_type())
+#define GST_RTP_KLV_DEPAY(obj) \
+ (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_RTP_KLV_DEPAY,GstRtpKlvDepay))
+#define GST_RTP_KLV_DEPAY_CLASS(klass) \
+ (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_RTP_KLV_DEPAY,GstRtpKlvDepayClass))
+#define GST_IS_RTP_KLV_DEPAY(obj) \
+ (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_RTP_KLV_DEPAY))
+#define GST_IS_RTP_KLV_DEPAY_CLASS(klass) \
+ (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_RTP_KLV_DEPAY))
+
+typedef struct _GstRtpKlvDepay GstRtpKlvDepay;
+typedef struct _GstRtpKlvDepayClass GstRtpKlvDepayClass;
+
+struct _GstRtpKlvDepay
+{
+ GstRTPBaseDepayload depayload;
+
+ GstAdapter *adapter;
+ gboolean resync;
+ gint64 last_rtp_ts; /* -1 if unset, otherwise 0-G_MAXUINT32 */
+};
+
+struct _GstRtpKlvDepayClass
+{
+ GstRTPBaseDepayloadClass parent_class;
+};
+
+G_GNUC_INTERNAL GType gst_rtp_klv_depay_get_type (void);
+
+G_GNUC_INTERNAL gboolean gst_rtp_klv_depay_plugin_init (GstPlugin * plugin);
+
+G_END_DECLS
+
+#endif /* __GST_RTP_KLV_DEPAY_H__ */
projects / platform / upstream / gst-plugins-good.git / commitdiff