From 1d8cbaf214199c55ba9c7210fa900001d59cc24c Mon Sep 17 00:00:00 2001 From: Nicolas Dufresne Date: Mon, 20 Jan 2020 16:52:14 -0500 Subject: gst: libcamerasrc: Add a task for the streaming thread Use a GstTask as our internal streaming thread. Unlike GstBaseSrc, we will be running a streaming thread at the element level rather than per pad. This is needed to combine buffer request for multiple pads. Signed-off-by: Nicolas Dufresne Reviewed-by: Laurent Pinchart Signed-off-by: Laurent Pinchart --- src/gstreamer/gstlibcamerasrc.cpp | 51 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) (limited to 'src/gstreamer') diff --git a/src/gstreamer/gstlibcamerasrc.cpp b/src/gstreamer/gstlibcamerasrc.cpp index fd0eaf5a..35f75124 100644 --- a/src/gstreamer/gstlibcamerasrc.cpp +++ b/src/gstreamer/gstlibcamerasrc.cpp @@ -27,7 +27,11 @@ struct GstLibcameraSrcState { struct _GstLibcameraSrc { GstElement parent; + + GRecMutex stream_lock; + GstTask *task; GstPad *srcpad; + gchar *camera_name; GstLibcameraSrcState *state; @@ -113,6 +117,30 @@ gst_libcamera_src_open(GstLibcameraSrc *self) return true; } +static void +gst_libcamera_src_task_run(gpointer user_data) +{ + GstLibcameraSrc *self = GST_LIBCAMERA_SRC(user_data); + + GST_DEBUG_OBJECT(self, "Streaming thread is now capturing"); +} + +static void +gst_libcamera_src_task_enter(GstTask *task, GThread *thread, gpointer user_data) +{ + GstLibcameraSrc *self = GST_LIBCAMERA_SRC(user_data); + + GST_DEBUG_OBJECT(self, "Streaming thread has started"); +} + +static void +gst_libcamera_src_task_leave(GstTask *task, GThread *thread, gpointer user_data) +{ + GstLibcameraSrc *self = GST_LIBCAMERA_SRC(user_data); + + GST_DEBUG_OBJECT(self, "Streaming thread is about to stop"); +} + static void gst_libcamera_src_close(GstLibcameraSrc *self) { @@ -183,9 +211,24 @@ gst_libcamera_src_change_state(GstElement *element, GstStateChange transition) return GST_STATE_CHANGE_FAILURE; break; case GST_STATE_CHANGE_READY_TO_PAUSED: + /* This needs to be called after pads activation.*/ + if (!gst_task_pause(self->task)) + return GST_STATE_CHANGE_FAILURE; + ret = GST_STATE_CHANGE_NO_PREROLL; + break; case GST_STATE_CHANGE_PLAYING_TO_PAUSED: ret = GST_STATE_CHANGE_NO_PREROLL; break; + case GST_STATE_CHANGE_PAUSED_TO_READY: + /* + * \todo this might require some thread unblocking in the future + * if the streaming thread starts doing any kind of blocking + * operations. If this was the case, we would need to do so + * before pad deactivation, so before chaining to the parent + * change_state function. + */ + gst_task_join(self->task); + break; case GST_STATE_CHANGE_READY_TO_NULL: gst_libcamera_src_close(self); break; @@ -202,6 +245,8 @@ gst_libcamera_src_finalize(GObject *object) GObjectClass *klass = G_OBJECT_CLASS(gst_libcamera_src_parent_class); GstLibcameraSrc *self = GST_LIBCAMERA_SRC(object); + g_rec_mutex_clear(&self->stream_lock); + g_clear_object(&self->task); g_free(self->camera_name); delete self->state; @@ -214,6 +259,12 @@ gst_libcamera_src_init(GstLibcameraSrc *self) GstLibcameraSrcState *state = new GstLibcameraSrcState(); GstPadTemplate *templ = gst_element_get_pad_template(GST_ELEMENT(self), "src"); + g_rec_mutex_init(&self->stream_lock); + self->task = gst_task_new(gst_libcamera_src_task_run, self, nullptr); + gst_task_set_enter_callback(self->task, gst_libcamera_src_task_enter, self, nullptr); + gst_task_set_leave_callback(self->task, gst_libcamera_src_task_leave, self, nullptr); + gst_task_set_lock(self->task, &self->stream_lock); + self->srcpad = gst_pad_new_from_template(templ, "src"); gst_element_add_pad(GST_ELEMENT(self), self->srcpad); self->state = state; -- cgit v1.2.1