| /* GStreamer Interleaved RTSP parser |
| * Copyright (C) 2011 Mark Nauwelaerts <mark.nauwelaerts@collabora.co.uk> |
| * Copyright (C) 2011 Nokia Corporation. All rights reserved. |
| * Contact: Stefan Kost <stefan.kost@nokia.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., 51 Franklin St, Fifth Floor, |
| * Boston, MA 02110-1301, USA. |
| */ |
| /** |
| * SECTION:element-irtspparse |
| * @short_description: Interleaved RTSP parser |
| * @see_also: #GstPcapParse |
| * |
| * This is an interleaved RTSP parser that allows extracting specific |
| * so-called "channels" from received interleaved (TCP) RTSP data |
| * (typically extracted from some network capture). |
| * |
| * <refsect2> |
| * <title>Example launch line</title> |
| * |[ |
| * gst-launch-1.0 filesrc location=h264crasher.pcap ! pcapparse ! irtspparse |
| * ! rtph264depay ! ffdec_h264 ! fakesink |
| * ]| Read from a pcap dump file using filesrc, extract the raw TCP packets, |
| * depayload and decode them. |
| * </refsect2> |
| */ |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #include <string.h> |
| |
| #include "gstirtspparse.h" |
| #include <gst/base/gstbytereader.h> |
| |
| GST_DEBUG_CATEGORY_STATIC (irtsp_parse_debug); |
| #define GST_CAT_DEFAULT irtsp_parse_debug |
| |
| enum |
| { |
| PROP_0, |
| PROP_CHANNEL_ID |
| }; |
| |
| |
| static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src", |
| GST_PAD_SRC, |
| GST_PAD_ALWAYS, |
| GST_STATIC_CAPS ("application/x-rtp ; application/x-rtcp")); |
| |
| static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink", |
| GST_PAD_SINK, |
| GST_PAD_ALWAYS, |
| GST_STATIC_CAPS_ANY); |
| |
| static void gst_irtsp_parse_finalize (GObject * object); |
| |
| static gboolean gst_irtsp_parse_start (GstBaseParse * parse); |
| static gboolean gst_irtsp_parse_stop (GstBaseParse * parse); |
| static GstFlowReturn gst_irtsp_parse_handle_frame (GstBaseParse * parse, |
| GstBaseParseFrame * frame, gint * skipsize); |
| |
| static void gst_irtsp_parse_set_property (GObject * object, |
| guint prop_id, const GValue * value, GParamSpec * pspec); |
| static void gst_irtsp_parse_get_property (GObject * object, |
| guint prop_id, GValue * value, GParamSpec * pspec); |
| |
| #define parent_class gst_irtsp_parse_parent_class |
| G_DEFINE_TYPE (GstIRTSPParse, gst_irtsp_parse, GST_TYPE_BASE_PARSE); |
| |
| static void |
| gst_irtsp_parse_class_init (GstIRTSPParseClass * klass) |
| { |
| GstBaseParseClass *parse_class = GST_BASE_PARSE_CLASS (klass); |
| GstElementClass *element_class = GST_ELEMENT_CLASS (klass); |
| GObjectClass *object_class = G_OBJECT_CLASS (klass); |
| |
| GST_DEBUG_CATEGORY_INIT (irtsp_parse_debug, "irtspparse", 0, |
| "Interleaved RTSP stream parser"); |
| |
| object_class->finalize = gst_irtsp_parse_finalize; |
| |
| object_class->set_property = gst_irtsp_parse_set_property; |
| object_class->get_property = gst_irtsp_parse_get_property; |
| |
| g_object_class_install_property (object_class, PROP_CHANNEL_ID, |
| g_param_spec_int ("channel-id", "channel-id", |
| "Channel Identifier", 0, 255, |
| 0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)); |
| |
| parse_class->start = GST_DEBUG_FUNCPTR (gst_irtsp_parse_start); |
| parse_class->stop = GST_DEBUG_FUNCPTR (gst_irtsp_parse_stop); |
| parse_class->handle_frame = GST_DEBUG_FUNCPTR (gst_irtsp_parse_handle_frame); |
| |
| gst_element_class_add_static_pad_template (element_class, &sink_template); |
| gst_element_class_add_static_pad_template (element_class, &src_template); |
| |
| gst_element_class_set_static_metadata (element_class, "IRTSPParse", |
| "Raw/Parser", |
| "Parses a raw interleaved RTSP stream", |
| "Mark Nauwelaerts <mark.nauwelaerts@collabora.co.uk>"); |
| } |
| |
| static void |
| gst_irtsp_parse_reset (GstIRTSPParse * IRTSPParse) |
| { |
| } |
| |
| static void |
| gst_irtsp_parse_init (GstIRTSPParse * IRTSPParse) |
| { |
| gst_base_parse_set_min_frame_size (GST_BASE_PARSE (IRTSPParse), 4); |
| gst_irtsp_parse_reset (IRTSPParse); |
| } |
| |
| static void |
| gst_irtsp_parse_finalize (GObject * object) |
| { |
| G_OBJECT_CLASS (parent_class)->finalize (object); |
| } |
| |
| static gboolean |
| gst_irtsp_parse_start (GstBaseParse * parse) |
| { |
| GstIRTSPParse *IRTSPParse = GST_IRTSP_PARSE (parse); |
| |
| GST_DEBUG_OBJECT (parse, "starting"); |
| |
| gst_irtsp_parse_reset (IRTSPParse); |
| |
| return TRUE; |
| } |
| |
| static gboolean |
| gst_irtsp_parse_stop (GstBaseParse * parse) |
| { |
| GST_DEBUG_OBJECT (parse, "stopping"); |
| |
| return TRUE; |
| } |
| |
| static GstFlowReturn |
| gst_irtsp_parse_handle_frame (GstBaseParse * parse, |
| GstBaseParseFrame * frame, gint * skipsize) |
| { |
| GstIRTSPParse *IRTSPParse = GST_IRTSP_PARSE (parse); |
| GstBuffer *buf = frame->buffer; |
| GstByteReader reader; |
| gint off; |
| GstMapInfo map; |
| guint framesize; |
| |
| gst_buffer_map (buf, &map, GST_MAP_READ); |
| if (G_UNLIKELY (map.size < 4)) |
| goto exit; |
| |
| gst_byte_reader_init (&reader, map.data, map.size); |
| |
| off = gst_byte_reader_masked_scan_uint32 (&reader, 0xffff0000, |
| 0x24000000 + (IRTSPParse->channel_id << 16), 0, map.size); |
| |
| GST_LOG_OBJECT (parse, "possible sync at buffer offset %d", off); |
| |
| /* didn't find anything that looks like a sync word, skip */ |
| if (off < 0) { |
| *skipsize = map.size - 3; |
| goto exit; |
| } |
| |
| /* possible frame header, but not at offset 0? skip bytes before sync */ |
| if (off > 0) { |
| *skipsize = off; |
| goto exit; |
| } |
| |
| framesize = GST_READ_UINT16_BE (map.data + 2) + 4; |
| GST_LOG_OBJECT (parse, "got frame size %d", framesize); |
| |
| if (!gst_pad_has_current_caps (GST_BASE_PARSE_SRC_PAD (parse))) { |
| GstCaps *caps; |
| |
| caps = gst_caps_new_empty_simple ("application/x-rtp"); |
| gst_pad_set_caps (GST_BASE_PARSE_SRC_PAD (parse), caps); |
| gst_caps_unref (caps); |
| } |
| |
| if (framesize <= map.size) { |
| gst_buffer_unmap (buf, &map); |
| /* HACK HACK skip header. |
| * could also ask baseparse to skip this, |
| * but that would give us a discontinuity for free |
| * which is a bit too much to have on all our packets */ |
| frame->out_buffer = gst_buffer_copy (frame->buffer); |
| gst_buffer_resize (frame->out_buffer, 4, -1); |
| GST_BUFFER_FLAG_UNSET (frame->out_buffer, GST_BUFFER_FLAG_DISCONT); |
| return gst_base_parse_finish_frame (parse, frame, framesize); |
| } |
| |
| exit: |
| gst_buffer_unmap (buf, &map); |
| return GST_FLOW_OK; |
| } |
| |
| static void |
| gst_irtsp_parse_set_property (GObject * object, |
| guint prop_id, const GValue * value, GParamSpec * pspec) |
| { |
| GstIRTSPParse *IRTSPParse = GST_IRTSP_PARSE (object); |
| |
| switch (prop_id) { |
| case PROP_CHANNEL_ID: |
| IRTSPParse->channel_id = g_value_get_int (value); |
| break; |
| default: |
| G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); |
| break; |
| } |
| } |
| |
| static void |
| gst_irtsp_parse_get_property (GObject * object, |
| guint prop_id, GValue * value, GParamSpec * pspec) |
| { |
| GstIRTSPParse *IRTSPParse = GST_IRTSP_PARSE (object); |
| |
| switch (prop_id) { |
| case PROP_CHANNEL_ID: |
| g_value_set_int (value, IRTSPParse->channel_id); |
| break; |
| default: |
| G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); |
| break; |
| } |
| } |