rpicamsrc: Add webrtc streaming example

Add an example for testing webrtc streaming from the rpi
camera, based on the code from
https://bugzilla.gnome.org/show_bug.cgi?id=795404

Requires GStreamer 1.14.1 or git master
This commit is contained in:
Jan Schmidt 2018-05-12 21:13:52 +00:00 committed by Tim-Philipp Müller
parent d5cd0c0301
commit 39a026760d

View file

@ -0,0 +1,663 @@
#include <glib.h>
#include <glib-unix.h>
#include <gst/gst.h>
#include <gst/sdp/sdp.h>
#define GST_USE_UNSTABLE_API
#include <gst/webrtc/webrtc.h>
#include <libsoup/soup.h>
#include <json-glib/json-glib.h>
#include <string.h>
#define RTP_PAYLOAD_TYPE "96"
#define SOUP_HTTP_PORT 57778
typedef struct _ReceiverEntry ReceiverEntry;
ReceiverEntry *create_receiver_entry (SoupWebsocketConnection * connection);
void destroy_receiver_entry (gpointer receiver_entry_ptr);
GstPadProbeReturn payloader_caps_event_probe_cb (GstPad * pad,
GstPadProbeInfo * info, gpointer user_data);
void on_offer_created_cb (GstPromise * promise, gpointer user_data);
void on_negotiation_needed_cb (GstElement * webrtcbin, gpointer user_data);
void on_ice_candidate_cb (GstElement * webrtcbin, guint mline_index,
gchar * candidate, gpointer user_data);
void soup_websocket_message_cb (SoupWebsocketConnection * connection,
SoupWebsocketDataType data_type, GBytes * message, gpointer user_data);
void soup_websocket_closed_cb (SoupWebsocketConnection * connection,
gpointer user_data);
void soup_http_handler (SoupServer * soup_server, SoupMessage * message,
const char *path, GHashTable * query, SoupClientContext * client_context,
gpointer user_data);
void soup_websocket_handler (G_GNUC_UNUSED SoupServer * server,
SoupWebsocketConnection * connection, const char *path,
SoupClientContext * client_context, gpointer user_data);
static gchar *get_string_from_json_object (JsonObject * object);
gboolean exit_sighandler (gpointer user_data);
struct _ReceiverEntry
{
SoupWebsocketConnection *connection;
GstElement *pipeline;
GstElement *webrtcbin;
GstElement *payloader;
GCond profile_level_id_cond;
GMutex profile_level_id_mutex;
gchar *profile_level_id;
gboolean shutting_down;
};
const gchar *html_source = " \n \
<html> \n \
<head> \n \
<script type=\"text/javascript\" src=\"https://webrtc.github.io/adapter/adapter-latest.js\"></script> \n \
<script type=\"text/javascript\"> \n \
var html5VideoElement; \n \
var websocketConnection; \n \
var webrtcPeerConnection; \n \
var webrtcConfiguration; \n \
var reportError; \n \
\n \
\n \
function onLocalDescription(desc) { \n \
console.log(\"Local description: \" + JSON.stringify(desc)); \n \
webrtcPeerConnection.setLocalDescription(desc).then(function() { \n \
websocketConnection.send(JSON.stringify({ type: \"sdp\", \"data\": webrtcPeerConnection.localDescription })); \n \
}).catch(reportError); \n \
} \n \
\n \
\n \
function onIncomingSDP(sdp) { \n \
console.log(\"Incoming SDP: \" + JSON.stringify(sdp)); \n \
webrtcPeerConnection.setRemoteDescription(sdp).catch(reportError); \n \
webrtcPeerConnection.createAnswer().then(onLocalDescription).catch(reportError); \n \
} \n \
\n \
\n \
function onIncomingICE(ice) { \n \
var candidate = new RTCIceCandidate(ice); \n \
console.log(\"Incoming ICE: \" + JSON.stringify(ice)); \n \
webrtcPeerConnection.addIceCandidate(candidate).catch(reportError); \n \
} \n \
\n \
\n \
function onAddRemoteStream(event) { \n \
html5VideoElement.srcObject = event.streams[0]; \n \
} \n \
\n \
\n \
function onIceCandidate(event) { \n \
if (event.candidate == null) \n \
return; \n \
\n \
console.log(\"Sending ICE candidate out: \" + JSON.stringify(event.candidate)); \n \
websocketConnection.send(JSON.stringify({ \"type\": \"ice\", \"data\": event.candidate })); \n \
} \n \
\n \
\n \
function onServerMessage(event) { \n \
var msg; \n \
\n \
try { \n \
msg = JSON.parse(event.data); \n \
} catch (e) { \n \
return; \n \
} \n \
\n \
if (!webrtcPeerConnection) { \n \
webrtcPeerConnection = new RTCPeerConnection(webrtcConfiguration); \n \
webrtcPeerConnection.ontrack = onAddRemoteStream; \n \
webrtcPeerConnection.onicecandidate = onIceCandidate; \n \
} \n \
\n \
switch (msg.type) { \n \
case \"sdp\": onIncomingSDP(msg.data); break; \n \
case \"ice\": onIncomingICE(msg.data); break; \n \
default: break; \n \
} \n \
} \n \
\n \
\n \
function playStream(videoElement, hostname, port, path, configuration, reportErrorCB) { \n \
var wsHost = (hostname != undefined) ? hostname : window.location.hostname; \n \
var wsPort = (port != undefined) ? port : 57778; \n \
var wsPath = (path != undefined) ? path : \"ws\"; \n \
var wsUrl = \"ws://\" + wsHost + \":\" + wsPort + \"/\" + wsPath; \n \
\n \
html5VideoElement = videoElement; \n \
webrtcConfiguration = configuration; \n \
reportError = (reportErrorCB != undefined) ? reportErrorCB : function(text) {}; \n \
\n \
websocketConnection = new WebSocket(wsUrl); \n \
websocketConnection.addEventListener(\"message\", onServerMessage); \n \
} \n \
\n \
window.onload = function() { \n \
var vidstream = document.getElementById(\"stream\"); \n \
playStream(vidstream, null, null, null, null, function (errmsg) { console.error(errmsg); }); \n \
}; \n \
\n \
</script> \n \
</head> \n \
\n \
<body> \n \
<div> \n \
<video id=\"stream\" autoplay>Your browser does not support video</video> \n \
</div> \n \
</body> \n \
</html> \n \
";
ReceiverEntry *
create_receiver_entry (SoupWebsocketConnection * connection)
{
GError *error;
ReceiverEntry *receiver_entry;
GstPad *payloader_srcpad;
receiver_entry = g_slice_alloc0 (sizeof (ReceiverEntry));
receiver_entry->connection = connection;
g_cond_init (&receiver_entry->profile_level_id_cond);
g_mutex_init (&receiver_entry->profile_level_id_mutex);
g_object_ref (G_OBJECT (connection));
g_signal_connect (G_OBJECT (connection), "message",
G_CALLBACK (soup_websocket_message_cb), (gpointer) receiver_entry);
error = NULL;
receiver_entry->pipeline = gst_parse_launch ("webrtcbin name=webrtcbin "
"rpicamsrc bitrate=300000 annotation-mode=12 ! video/x-h264,profile=baseline,width=640,height=480 ! queue max-size-time=100000000 ! h264parse ! "
"rtph264pay config-interval=-1 name=payloader ! "
"application/x-rtp,media=video,encoding-name=H264,payload="
RTP_PAYLOAD_TYPE " ! webrtcbin. ", &error);
if (error != NULL) {
g_error ("Could not create WebRTC pipeline: %s\n", error->message);
g_error_free (error);
goto cleanup;
}
receiver_entry->webrtcbin =
gst_bin_get_by_name (GST_BIN (receiver_entry->pipeline), "webrtcbin");
receiver_entry->payloader =
gst_bin_get_by_name (GST_BIN (receiver_entry->pipeline), "payloader");
g_assert (receiver_entry->webrtcbin != NULL);
g_assert (receiver_entry->payloader != NULL);
payloader_srcpad =
gst_element_get_static_pad (receiver_entry->payloader, "src");
gst_pad_add_probe (payloader_srcpad, GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM,
payloader_caps_event_probe_cb, (gpointer) receiver_entry, NULL);
gst_object_unref (GST_OBJECT (payloader_srcpad));
g_signal_connect (receiver_entry->webrtcbin, "on-negotiation-needed",
G_CALLBACK (on_negotiation_needed_cb), (gpointer) receiver_entry);
g_signal_connect (receiver_entry->webrtcbin, "on-ice-candidate",
G_CALLBACK (on_ice_candidate_cb), (gpointer) receiver_entry);
gst_element_set_state (receiver_entry->pipeline, GST_STATE_PLAYING);
return receiver_entry;
cleanup:
destroy_receiver_entry ((gpointer) receiver_entry);
return NULL;
}
void
destroy_receiver_entry (gpointer receiver_entry_ptr)
{
ReceiverEntry *receiver_entry = (ReceiverEntry *) receiver_entry_ptr;
g_assert (receiver_entry != NULL);
g_mutex_lock (&receiver_entry->profile_level_id_mutex);
receiver_entry->shutting_down = TRUE;
g_cond_signal (&receiver_entry->profile_level_id_cond);
g_mutex_unlock (&receiver_entry->profile_level_id_mutex);
if (receiver_entry->pipeline != NULL) {
gst_element_set_state (GST_ELEMENT (receiver_entry->pipeline),
GST_STATE_NULL);
gst_object_unref (GST_OBJECT (receiver_entry->webrtcbin));
gst_object_unref (GST_OBJECT (receiver_entry->payloader));
gst_object_unref (GST_OBJECT (receiver_entry->pipeline));
}
g_cond_clear (&receiver_entry->profile_level_id_cond);
g_mutex_clear (&receiver_entry->profile_level_id_mutex);
g_free (receiver_entry->profile_level_id);
if (receiver_entry->connection != NULL)
g_object_unref (G_OBJECT (receiver_entry->connection));
g_slice_free1 (sizeof (ReceiverEntry), receiver_entry);
}
GstPadProbeReturn
payloader_caps_event_probe_cb (G_GNUC_UNUSED GstPad * pad,
GstPadProbeInfo * info, gpointer user_data)
{
ReceiverEntry *receiver_entry = (ReceiverEntry *) user_data;
GstEvent *event = GST_PAD_PROBE_INFO_EVENT (info);
if (GST_EVENT_TYPE (event) == GST_EVENT_CAPS) {
gchar const *profile_level_id;
GstStructure *s;
GstCaps *caps;
caps = NULL;
gst_event_parse_caps (event, &caps);
s = gst_caps_get_structure (caps, 0);
profile_level_id = gst_structure_get_string (s, "profile-level-id");
g_assert (profile_level_id != NULL);
g_mutex_lock (&receiver_entry->profile_level_id_mutex);
g_free (receiver_entry->profile_level_id);
receiver_entry->profile_level_id = g_strdup (profile_level_id);
g_cond_signal (&receiver_entry->profile_level_id_cond);
g_mutex_unlock (&receiver_entry->profile_level_id_mutex);
}
return GST_PAD_PROBE_OK;
}
void
on_offer_created_cb (GstPromise * promise, gpointer user_data)
{
gchar *fmtp_value;
gchar *sdp_string;
gchar *json_string;
JsonObject *sdp_json;
JsonObject *sdp_data_json;
GstSDPMedia *sdp_media;
GstStructure const *reply;
GstPromise *local_desc_promise;
GstWebRTCSessionDescription *offer = NULL;
ReceiverEntry *receiver_entry = (ReceiverEntry *) user_data;
reply = gst_promise_get_reply (promise);
gst_structure_get (reply, "offer", GST_TYPE_WEBRTC_SESSION_DESCRIPTION,
&offer, NULL);
gst_promise_unref (promise);
fmtp_value = g_strdup_printf (RTP_PAYLOAD_TYPE " profile-level-id=%s",
receiver_entry->profile_level_id);
sdp_media =
(GstSDPMedia *) & g_array_index (offer->sdp->medias, GstSDPMedia, 0);
gst_sdp_media_add_attribute (sdp_media, "fmtp", fmtp_value);
g_free (fmtp_value);
local_desc_promise = gst_promise_new ();
g_signal_emit_by_name (receiver_entry->webrtcbin, "set-local-description",
offer, local_desc_promise);
gst_promise_interrupt (local_desc_promise);
gst_promise_unref (local_desc_promise);
sdp_string = gst_sdp_message_as_text (offer->sdp);
g_print ("Negotiation offer created:\n%s\n", sdp_string);
sdp_json = json_object_new ();
json_object_set_string_member (sdp_json, "type", "sdp");
sdp_data_json = json_object_new ();
json_object_set_string_member (sdp_data_json, "type", "offer");
json_object_set_string_member (sdp_data_json, "sdp", sdp_string);
json_object_set_object_member (sdp_json, "data", sdp_data_json);
json_string = get_string_from_json_object (sdp_json);
json_object_unref (sdp_json);
soup_websocket_connection_send_text (receiver_entry->connection, json_string);
g_free (json_string);
gst_webrtc_session_description_free (offer);
}
void
on_negotiation_needed_cb (GstElement * webrtcbin, gpointer user_data)
{
gboolean exit_early;
GstPromise *promise;
ReceiverEntry *receiver_entry = (ReceiverEntry *) user_data;
g_mutex_lock (&receiver_entry->profile_level_id_mutex);
while ((receiver_entry->profile_level_id == NULL)
&& !receiver_entry->shutting_down)
g_cond_wait (&receiver_entry->profile_level_id_cond,
&receiver_entry->profile_level_id_mutex);
exit_early = receiver_entry->shutting_down;
g_mutex_unlock (&receiver_entry->profile_level_id_mutex);
if (exit_early)
return;
g_print ("Creating negotiation offer\n");
promise = gst_promise_new_with_change_func (on_offer_created_cb,
(gpointer) receiver_entry, NULL);
g_signal_emit_by_name (G_OBJECT (webrtcbin), "create-offer", NULL, promise);
}
void
on_ice_candidate_cb (G_GNUC_UNUSED GstElement * webrtcbin, guint mline_index,
gchar * candidate, gpointer user_data)
{
JsonObject *ice_json;
JsonObject *ice_data_json;
gchar *json_string;
ReceiverEntry *receiver_entry = (ReceiverEntry *) user_data;
ice_json = json_object_new ();
json_object_set_string_member (ice_json, "type", "ice");
ice_data_json = json_object_new ();
json_object_set_int_member (ice_data_json, "sdpMLineIndex", mline_index);
json_object_set_string_member (ice_data_json, "candidate", candidate);
json_object_set_object_member (ice_json, "data", ice_data_json);
json_string = get_string_from_json_object (ice_json);
json_object_unref (ice_json);
soup_websocket_connection_send_text (receiver_entry->connection, json_string);
g_free (json_string);
}
void
soup_websocket_message_cb (G_GNUC_UNUSED SoupWebsocketConnection * connection,
SoupWebsocketDataType data_type, GBytes * message, gpointer user_data)
{
gsize size;
gchar *data;
gchar *data_string;
const gchar *type_string;
JsonNode *root_json;
JsonObject *root_json_object;
JsonObject *data_json_object;
JsonParser *json_parser = NULL;
ReceiverEntry *receiver_entry = (ReceiverEntry *) user_data;
switch (data_type) {
case SOUP_WEBSOCKET_DATA_BINARY:
g_error ("Received unknown binary message, ignoring\n");
g_bytes_unref (message);
return;
case SOUP_WEBSOCKET_DATA_TEXT:
data = g_bytes_unref_to_data (message, &size);
/* Convert to NULL-terminated string */
data_string = g_strndup (data, size);
g_free (data);
break;
default:
g_assert_not_reached ();
}
json_parser = json_parser_new ();
if (!json_parser_load_from_data (json_parser, data_string, -1, NULL))
goto unknown_message;
root_json = json_parser_get_root (json_parser);
if (!JSON_NODE_HOLDS_OBJECT (root_json))
goto unknown_message;
root_json_object = json_node_get_object (root_json);
if (!json_object_has_member (root_json_object, "type")) {
g_error ("Received message without type field\n");
goto cleanup;
}
type_string = json_object_get_string_member (root_json_object, "type");
if (!json_object_has_member (root_json_object, "data")) {
g_error ("Received message without data field\n");
goto cleanup;
}
data_json_object = json_object_get_object_member (root_json_object, "data");
if (g_strcmp0 (type_string, "sdp") == 0) {
const gchar *sdp_type_string;
const gchar *sdp_string;
GstPromise *promise;
GstSDPMessage *sdp;
GstWebRTCSessionDescription *answer;
int ret;
if (!json_object_has_member (data_json_object, "type")) {
g_error ("Received SDP message without type field\n");
goto cleanup;
}
sdp_type_string = json_object_get_string_member (data_json_object, "type");
if (g_strcmp0 (sdp_type_string, "answer") != 0) {
g_error ("Expected SDP message type \"answer\", got \"%s\"\n",
sdp_type_string);
goto cleanup;
}
if (!json_object_has_member (data_json_object, "sdp")) {
g_error ("Received SDP message without SDP string\n");
goto cleanup;
}
sdp_string = json_object_get_string_member (data_json_object, "sdp");
g_print ("Received SDP:\n%s\n", sdp_string);
ret = gst_sdp_message_new (&sdp);
g_assert_cmphex (ret, ==, GST_SDP_OK);
ret =
gst_sdp_message_parse_buffer ((guint8 *) sdp_string,
strlen (sdp_string), sdp);
if (ret != GST_SDP_OK) {
g_error ("Could not parse SDP string\n");
goto cleanup;
}
answer = gst_webrtc_session_description_new (GST_WEBRTC_SDP_TYPE_ANSWER,
sdp);
g_assert_nonnull (answer);
promise = gst_promise_new ();
g_signal_emit_by_name (receiver_entry->webrtcbin, "set-remote-description",
answer, promise);
gst_promise_interrupt (promise);
gst_promise_unref (promise);
} else if (g_strcmp0 (type_string, "ice") == 0) {
guint mline_index;
const gchar *candidate_string;
if (!json_object_has_member (data_json_object, "sdpMLineIndex")) {
g_error ("Received ICE message without mline index\n");
goto cleanup;
}
mline_index =
json_object_get_int_member (data_json_object, "sdpMLineIndex");
if (!json_object_has_member (data_json_object, "candidate")) {
g_error ("Received ICE message without ICE candidate string\n");
goto cleanup;
}
candidate_string = json_object_get_string_member (data_json_object,
"candidate");
g_print ("Received ICE candidate with mline index %u; candidate: %s\n",
mline_index, candidate_string);
g_signal_emit_by_name (receiver_entry->webrtcbin, "add-ice-candidate",
mline_index, candidate_string);
} else
goto unknown_message;
cleanup:
if (json_parser != NULL)
g_object_unref (G_OBJECT (json_parser));
g_free (data_string);
return;
unknown_message:
g_error ("Unknown message \"%s\", ignoring", data_string);
goto cleanup;
}
void
soup_websocket_closed_cb (SoupWebsocketConnection * connection,
gpointer user_data)
{
GHashTable *receiver_entry_table = (GHashTable *) user_data;
g_hash_table_remove (receiver_entry_table, connection);
g_print ("Closed websocket connection %p\n", (gpointer) connection);
}
void
soup_http_handler (G_GNUC_UNUSED SoupServer * soup_server,
SoupMessage * message, const char *path, G_GNUC_UNUSED GHashTable * query,
G_GNUC_UNUSED SoupClientContext * client_context,
G_GNUC_UNUSED gpointer user_data)
{
SoupBuffer *soup_buffer;
if ((g_strcmp0 (path, "/") != 0) && (g_strcmp0 (path, "/index.html") != 0)) {
soup_message_set_status (message, SOUP_STATUS_NOT_FOUND);
return;
}
soup_buffer =
soup_buffer_new (SOUP_MEMORY_STATIC, html_source, strlen (html_source));
soup_message_headers_set_content_type (message->response_headers, "text/html",
NULL);
soup_message_body_append_buffer (message->response_body, soup_buffer);
soup_buffer_free (soup_buffer);
soup_message_set_status (message, SOUP_STATUS_OK);
}
void
soup_websocket_handler (G_GNUC_UNUSED SoupServer * server,
SoupWebsocketConnection * connection, G_GNUC_UNUSED const char *path,
G_GNUC_UNUSED SoupClientContext * client_context, gpointer user_data)
{
ReceiverEntry *receiver_entry;
GHashTable *receiver_entry_table = (GHashTable *) user_data;
g_print ("Processing new websocket connection %p", (gpointer) connection);
g_signal_connect (G_OBJECT (connection), "closed",
G_CALLBACK (soup_websocket_closed_cb), (gpointer) receiver_entry_table);
receiver_entry = create_receiver_entry (connection);
g_hash_table_replace (receiver_entry_table, connection, receiver_entry);
}
static gchar *
get_string_from_json_object (JsonObject * object)
{
JsonNode *root;
JsonGenerator *generator;
gchar *text;
/* Make it the root node */
root = json_node_init_object (json_node_alloc (), object);
generator = json_generator_new ();
json_generator_set_root (generator, root);
text = json_generator_to_data (generator, NULL);
/* Release everything */
g_object_unref (generator);
json_node_free (root);
return text;
}
gboolean
exit_sighandler (gpointer user_data)
{
g_print ("Caught signal, stopping mainloop\n");
GMainLoop *mainloop = (GMainLoop *) user_data;
g_main_loop_quit (mainloop);
return TRUE;
}
int
main (int argc, char *argv[])
{
GMainLoop *mainloop;
SoupServer *soup_server;
GHashTable *receiver_entry_table;
gst_init (&argc, &argv);
receiver_entry_table =
g_hash_table_new_full (g_direct_hash, g_direct_equal, NULL,
destroy_receiver_entry);
mainloop = g_main_loop_new (NULL, FALSE);
g_assert (mainloop != NULL);
g_unix_signal_add (SIGINT, exit_sighandler, mainloop);
g_unix_signal_add (SIGTERM, exit_sighandler, mainloop);
soup_server =
soup_server_new (SOUP_SERVER_SERVER_HEADER, "webrtc-soup-server", NULL);
soup_server_add_handler (soup_server, "/", soup_http_handler, NULL, NULL);
soup_server_add_websocket_handler (soup_server, "/ws", NULL, NULL,
soup_websocket_handler, (gpointer) receiver_entry_table, NULL);
soup_server_listen_all (soup_server, SOUP_HTTP_PORT,
(SoupServerListenOptions) 0, NULL);
g_print ("WebRTC page link: http://127.0.0.1:%d/\n", (gint) SOUP_HTTP_PORT);
g_main_loop_run (mainloop);
g_object_unref (G_OBJECT (soup_server));
g_hash_table_destroy (receiver_entry_table);
g_main_loop_unref (mainloop);
gst_deinit ();
return 0;
}