video: Update for subclassing API changes

22 files changed, 479 insertions, 230 deletions

diff --git a/video/closedcaption/src/caption_frame.rs b/video/closedcaption/src/caption_frame.rs
index ac5aad5df..724757500 100644
--- a/video/closedcaption/src/caption_frame.rs
+++ b/video/closedcaption/src/caption_frame.rs
@@ -6,7 +6,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use super::cea608tott_ffi as ffi;
+use super::ffi;
 use std::mem;
 
 #[derive(Copy, Clone, Debug)]
diff --git a/video/closedcaption/src/ccdetect.rs b/video/closedcaption/src/ccdetect/imp.rs
index 6c51c538d..488c1b16e 100644
--- a/video/closedcaption/src/ccdetect.rs
+++ b/video/closedcaption/src/ccdetect/imp.rs
@@ -69,7 +69,7 @@ struct State {
     last_cc708_change: gst::ClockTime,
 }
 
-struct CCDetect {
+pub struct CCDetect {
     settings: Mutex<Settings>,
     state: Mutex<Option<State>>,
 }
@@ -321,7 +321,7 @@ impl CCDetect {
 
     fn maybe_update_properties(
         &self,
-        element: &gst_base::BaseTransform,
+        element: &super::CCDetect,
         ts: gst::ClockTime,
         cc_packet: CCPacketContents,
     ) -> Result<(), gst::FlowError> {
@@ -382,6 +382,7 @@ impl CCDetect {
 
 impl ObjectSubclass for CCDetect {
     const NAME: &'static str = "CCDetect";
+    type Type = super::CCDetect;
     type ParentType = gst_base::BaseTransform;
     type Instance = gst::subclass::ElementInstanceStruct<Self>;
     type Class = subclass::simple::ClassStruct<Self>;
@@ -395,7 +396,7 @@ impl ObjectSubclass for CCDetect {
         }
     }
 
-    fn class_init(klass: &mut subclass::simple::ClassStruct<Self>) {
+    fn class_init(klass: &mut Self::Class) {
         klass.set_metadata(
             "Closed Caption Detect",
             "Filter/Video/ClosedCaption/Detect",
@@ -441,7 +442,7 @@ impl ObjectSubclass for CCDetect {
 }
 
 impl ObjectImpl for CCDetect {
-    fn set_property(&self, _obj: &glib::Object, id: usize, value: &glib::Value) {
+    fn set_property(&self, _obj: &Self::Type, id: usize, value: &glib::Value) {
         let prop = &PROPERTIES[id];
 
         match *prop {
@@ -453,7 +454,7 @@ impl ObjectImpl for CCDetect {
         }
     }
 
-    fn get_property(&self, _obj: &glib::Object, id: usize) -> Result<glib::Value, ()> {
+    fn get_property(&self, _obj: &Self::Type, id: usize) -> Result<glib::Value, ()> {
         let prop = &PROPERTIES[id];
 
         match *prop {
@@ -479,7 +480,7 @@ impl ElementImpl for CCDetect {}
 impl BaseTransformImpl for CCDetect {
     fn transform_ip_passthrough(
         &self,
-        element: &gst_base::BaseTransform,
+        element: &Self::Type,
         buf: &gst::Buffer,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
         let map = buf.map_readable().map_err(|_| gst::FlowError::Error)?;
@@ -517,7 +518,7 @@ impl BaseTransformImpl for CCDetect {
         Ok(gst::FlowSuccess::Ok)
     }
 
-    fn sink_event(&self, element: &gst_base::BaseTransform, event: gst::Event) -> bool {
+    fn sink_event(&self, element: &Self::Type, event: gst::Event) -> bool {
         match event.view() {
             gst::event::EventView::Gap(gap) => {
                 let _ = self.maybe_update_properties(
@@ -536,7 +537,7 @@ impl BaseTransformImpl for CCDetect {
 
     fn set_caps(
         &self,
-        _element: &gst_base::BaseTransform,
+        _element: &Self::Type,
         incaps: &gst::Caps,
         outcaps: &gst::Caps,
     ) -> Result<(), gst::LoggableError> {
@@ -569,19 +570,10 @@ impl BaseTransformImpl for CCDetect {
         Ok(())
     }
 
-    fn stop(&self, _element: &gst_base::BaseTransform) -> Result<(), gst::ErrorMessage> {
+    fn stop(&self, _element: &Self::Type) -> Result<(), gst::ErrorMessage> {
         // Drop state
         let _ = self.state.lock().unwrap().take();
 
         Ok(())
     }
 }
-
-pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
-    gst::Element::register(
-        Some(plugin),
-        "ccdetect",
-        gst::Rank::None,
-        CCDetect::get_type(),
-    )
-}
diff --git a/video/closedcaption/src/ccdetect/mod.rs b/video/closedcaption/src/ccdetect/mod.rs
new file mode 100644
index 000000000..11a82b86b
--- /dev/null
+++ b/video/closedcaption/src/ccdetect/mod.rs
@@ -0,0 +1,38 @@
+// Copyright (C) 2020 Matthew Waters <matthew@centricular.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 Street, Suite 500,
+// Boston, MA 02110-1335, USA.
+
+use glib::prelude::*;
+
+mod imp;
+
+glib_wrapper! {
+    pub struct CCDetect(ObjectSubclass<imp::CCDetect>) @extends gst_base::BaseTransform, gst::Element, gst::Object;
+}
+
+// GStreamer elements need to be thread-safe. For the private implementation this is automatically
+// enforced but for the public wrapper type we need to specify this manually.
+unsafe impl Send for CCDetect {}
+unsafe impl Sync for CCDetect {}
+
+pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
+    gst::Element::register(
+        Some(plugin),
+        "ccdetect",
+        gst::Rank::None,
+        CCDetect::static_type(),
+    )
+}
diff --git a/video/closedcaption/src/cea608overlay.rs b/video/closedcaption/src/cea608overlay/imp.rs
index 0df857c78..e55c16c8c 100644
--- a/video/closedcaption/src/cea608overlay.rs
+++ b/video/closedcaption/src/cea608overlay/imp.rs
@@ -15,13 +15,6 @@
 // Free Software Foundation, Inc., 51 Franklin Street, Suite 500,
 // Boston, MA 02110-1335, USA.
 
-// Example command-line:
-//
-// gst-launch-1.0 cccombiner name=ccc ! cea608overlay ! autovideosink \
-//   videotestsrc ! video/x-raw, width=1280, height=720 ! queue ! ccc.sink \
-//   filesrc location=input.srt ! subparse ! tttocea608 ! queue ! ccc.caption
-
-use glib::prelude::*;
 use glib::subclass;
 use glib::subclass::prelude::*;
 use gst::prelude::*;
@@ -68,7 +61,7 @@ impl Default for State {
 
 unsafe impl Send for State {}
 
-struct Cea608Overlay {
+pub struct Cea608Overlay {
     srcpad: gst::Pad,
     sinkpad: gst::Pad,
     state: Mutex<State>,
@@ -86,7 +79,7 @@ impl Cea608Overlay {
     // TODO: switch to the API presented in this post once it's been exposed
     fn recalculate_layout(
         &self,
-        element: &gst::Element,
+        element: &super::Cea608Overlay,
         state: &mut State,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
         let video_info = state.video_info.as_ref().unwrap();
@@ -242,7 +235,7 @@ impl Cea608Overlay {
 
     fn negotiate(
         &self,
-        element: &gst::Element,
+        element: &super::Cea608Overlay,
         state: &mut State,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
         let video_info = match state.video_info.as_ref() {
@@ -294,7 +287,7 @@ impl Cea608Overlay {
     fn sink_chain(
         &self,
         pad: &gst::Pad,
-        element: &gst::Element,
+        element: &super::Cea608Overlay,
         mut buffer: gst::Buffer,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
         gst_log!(CAT, obj: pad, "Handling buffer {:?}", buffer);
@@ -358,7 +351,12 @@ impl Cea608Overlay {
         self.srcpad.push(buffer)
     }
 
-    fn sink_event(&self, pad: &gst::Pad, element: &gst::Element, event: gst::Event) -> bool {
+    fn sink_event(
+        &self,
+        pad: &gst::Pad,
+        element: &super::Cea608Overlay,
+        event: gst::Event,
+    ) -> bool {
         use gst::EventView;
 
         gst_log!(CAT, obj: pad, "Handling event {:?}", event);
@@ -388,13 +386,14 @@ impl Cea608Overlay {
 
 impl ObjectSubclass for Cea608Overlay {
     const NAME: &'static str = "RsCea608Overlay";
+    type Type = super::Cea608Overlay;
     type ParentType = gst::Element;
     type Instance = gst::subclass::ElementInstanceStruct<Self>;
     type Class = subclass::simple::ClassStruct<Self>;
 
     glib_object_subclass!();
 
-    fn with_class(klass: &subclass::simple::ClassStruct<Self>) -> Self {
+    fn with_class(klass: &Self::Class) -> Self {
         let templ = klass.get_pad_template("sink").unwrap();
         let sinkpad = gst::Pad::builder_with_template(&templ, Some("sink"))
             .chain_function(|pad, parent, buffer| {
@@ -426,7 +425,7 @@ impl ObjectSubclass for Cea608Overlay {
         }
     }
 
-    fn class_init(klass: &mut subclass::simple::ClassStruct<Self>) {
+    fn class_init(klass: &mut Self::Class) {
         klass.set_metadata(
             "Cea 608 overlay",
             "Video/Overlay/Subtitle",
@@ -460,19 +459,18 @@ impl ObjectSubclass for Cea608Overlay {
 }
 
 impl ObjectImpl for Cea608Overlay {
-    fn constructed(&self, obj: &glib::Object) {
+    fn constructed(&self, obj: &Self::Type) {
         self.parent_constructed(obj);
 
-        let element = obj.downcast_ref::<gst::Element>().unwrap();
-        element.add_pad(&self.sinkpad).unwrap();
-        element.add_pad(&self.srcpad).unwrap();
+        obj.add_pad(&self.sinkpad).unwrap();
+        obj.add_pad(&self.srcpad).unwrap();
     }
 }
 
 impl ElementImpl for Cea608Overlay {
     fn change_state(
         &self,
-        element: &gst::Element,
+        element: &Self::Type,
         transition: gst::StateChange,
     ) -> Result<gst::StateChangeSuccess, gst::StateChangeError> {
         gst_trace!(CAT, obj: element, "Changing state {:?}", transition);
@@ -489,12 +487,3 @@ impl ElementImpl for Cea608Overlay {
         self.parent_change_state(element, transition)
     }
 }
-
-pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
-    gst::Element::register(
-        Some(plugin),
-        "cea608overlay",
-        gst::Rank::Primary,
-        Cea608Overlay::get_type(),
-    )
-}
diff --git a/video/closedcaption/src/cea608overlay/mod.rs b/video/closedcaption/src/cea608overlay/mod.rs
new file mode 100644
index 000000000..54669bf3e
--- /dev/null
+++ b/video/closedcaption/src/cea608overlay/mod.rs
@@ -0,0 +1,44 @@
+// Copyright (C) 2020 Mathieu Duponchelle <mathieu@centricular.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 Street, Suite 500,
+// Boston, MA 02110-1335, USA.
+
+// Example command-line:
+//
+// gst-launch-1.0 cccombiner name=ccc ! cea608overlay ! autovideosink \
+//   videotestsrc ! video/x-raw, width=1280, height=720 ! queue ! ccc.sink \
+//   filesrc location=input.srt ! subparse ! tttocea608 ! queue ! ccc.caption
+
+use glib::prelude::*;
+
+mod imp;
+
+glib_wrapper! {
+    pub struct Cea608Overlay(ObjectSubclass<imp::Cea608Overlay>) @extends gst::Element, gst::Object;
+}
+
+// GStreamer elements need to be thread-safe. For the private implementation this is automatically
+// enforced but for the public wrapper type we need to specify this manually.
+unsafe impl Send for Cea608Overlay {}
+unsafe impl Sync for Cea608Overlay {}
+
+pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
+    gst::Element::register(
+        Some(plugin),
+        "cea608overlay",
+        gst::Rank::Primary,
+        Cea608Overlay::static_type(),
+    )
+}
diff --git a/video/closedcaption/src/cea608tott.rs b/video/closedcaption/src/cea608tott/imp.rs
index edcb8002f..6dbc36ace 100644
--- a/video/closedcaption/src/cea608tott.rs
+++ b/video/closedcaption/src/cea608tott/imp.rs
@@ -6,7 +6,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use glib::prelude::*;
 use glib::subclass;
 use glib::subclass::prelude::*;
 use gst::prelude::*;
@@ -42,7 +41,7 @@ impl Default for State {
     }
 }
 
-struct Cea608ToTt {
+pub struct Cea608ToTt {
     srcpad: gst::Pad,
     sinkpad: gst::Pad,
 
@@ -61,7 +60,7 @@ impl Cea608ToTt {
     fn sink_chain(
         &self,
         pad: &gst::Pad,
-        _element: &gst::Element,
+        _element: &super::Cea608ToTt,
         buffer: gst::Buffer,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
         gst_log!(CAT, obj: pad, "Handling buffer {:?}", buffer);
@@ -271,7 +270,7 @@ impl Cea608ToTt {
         buffer
     }
 
-    fn sink_event(&self, pad: &gst::Pad, element: &gst::Element, event: gst::Event) -> bool {
+    fn sink_event(&self, pad: &gst::Pad, element: &super::Cea608ToTt, event: gst::Event) -> bool {
         use gst::EventView;
 
         gst_log!(CAT, obj: pad, "Handling event {:?}", event);
@@ -371,13 +370,14 @@ impl Cea608ToTt {
 
 impl ObjectSubclass for Cea608ToTt {
     const NAME: &'static str = "Cea608ToTt";
+    type Type = super::Cea608ToTt;
     type ParentType = gst::Element;
     type Instance = gst::subclass::ElementInstanceStruct<Self>;
     type Class = subclass::simple::ClassStruct<Self>;
 
     glib_object_subclass!();
 
-    fn with_class(klass: &subclass::simple::ClassStruct<Self>) -> Self {
+    fn with_class(klass: &Self::Class) -> Self {
         let templ = klass.get_pad_template("sink").unwrap();
         let sinkpad = gst::Pad::builder_with_template(&templ, Some("sink"))
             .chain_function(|pad, parent, buffer| {
@@ -409,7 +409,7 @@ impl ObjectSubclass for Cea608ToTt {
         }
     }
 
-    fn class_init(klass: &mut subclass::simple::ClassStruct<Self>) {
+    fn class_init(klass: &mut Self::Class) {
         klass.set_metadata(
             "CEA-608 to TT",
             "Generic",
@@ -461,19 +461,18 @@ impl ObjectSubclass for Cea608ToTt {
 }
 
 impl ObjectImpl for Cea608ToTt {
-    fn constructed(&self, obj: &glib::Object) {
+    fn constructed(&self, obj: &Self::Type) {
         self.parent_constructed(obj);
 
-        let element = obj.downcast_ref::<gst::Element>().unwrap();
-        element.add_pad(&self.sinkpad).unwrap();
-        element.add_pad(&self.srcpad).unwrap();
+        obj.add_pad(&self.sinkpad).unwrap();
+        obj.add_pad(&self.srcpad).unwrap();
     }
 }
 
 impl ElementImpl for Cea608ToTt {
     fn change_state(
         &self,
-        element: &gst::Element,
+        element: &Self::Type,
         transition: gst::StateChange,
     ) -> Result<gst::StateChangeSuccess, gst::StateChangeError> {
         gst_trace!(CAT, obj: element, "Changing state {:?}", transition);
@@ -499,12 +498,3 @@ impl ElementImpl for Cea608ToTt {
         Ok(ret)
     }
 }
-
-pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
-    gst::Element::register(
-        Some(plugin),
-        "cea608tott",
-        gst::Rank::None,
-        Cea608ToTt::get_type(),
-    )
-}
diff --git a/video/closedcaption/src/cea608tott/mod.rs b/video/closedcaption/src/cea608tott/mod.rs
new file mode 100644
index 000000000..51b23dc8a
--- /dev/null
+++ b/video/closedcaption/src/cea608tott/mod.rs
@@ -0,0 +1,29 @@
+// Copyright (C) 2020 Sebastian Dröge <sebastian@centricular.com>
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use glib::prelude::*;
+
+mod imp;
+
+glib_wrapper! {
+    pub struct Cea608ToTt(ObjectSubclass<imp::Cea608ToTt>) @extends gst::Element, gst::Object;
+}
+
+// GStreamer elements need to be thread-safe. For the private implementation this is automatically
+// enforced but for the public wrapper type we need to specify this manually.
+unsafe impl Send for Cea608ToTt {}
+unsafe impl Sync for Cea608ToTt {}
+
+pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
+    gst::Element::register(
+        Some(plugin),
+        "cea608tott",
+        gst::Rank::None,
+        Cea608ToTt::static_type(),
+    )
+}
diff --git a/video/closedcaption/src/cea608tott_ffi.rs b/video/closedcaption/src/ffi.rs
index a59e87fca..a59e87fca 100644
--- a/video/closedcaption/src/cea608tott_ffi.rs
+++ b/video/closedcaption/src/ffi.rs
diff --git a/video/closedcaption/src/lib.rs b/video/closedcaption/src/lib.rs
index 9ba22abf8..65690d40c 100644
--- a/video/closedcaption/src/lib.rs
+++ b/video/closedcaption/src/lib.rs
@@ -17,11 +17,6 @@
 
 #![recursion_limit = "128"]
 
-// These macros are in weird paths currently,
-// and extern crate is used to avoid the explicit imports
-// should not be needed ideally in the upcoming releases.
-// https://github.com/gtk-rs/glib/issues/420
-// https://gitlab.freedesktop.org/gstreamer/gstreamer-rs/issues/170
 #[macro_use]
 extern crate glib;
 #[macro_use]
@@ -33,21 +28,20 @@ extern crate lazy_static;
 #[macro_use]
 extern crate pretty_assertions;
 
+#[allow(non_camel_case_types, non_upper_case_globals, unused)]
+#[allow(clippy::redundant_static_lifetimes, clippy::unreadable_literal)]
+#[allow(clippy::useless_transmute, clippy::trivially_copy_pass_by_ref)]
+mod ffi;
+
 mod caption_frame;
 mod ccdetect;
 mod cea608overlay;
 mod cea608tott;
-#[allow(non_camel_case_types, non_upper_case_globals)]
-#[allow(clippy::redundant_static_lifetimes, clippy::unreadable_literal)]
-#[allow(clippy::useless_transmute, clippy::trivially_copy_pass_by_ref)]
-pub mod cea608tott_ffi;
 mod line_reader;
 mod mcc_enc;
 mod mcc_parse;
-mod mcc_parser;
 mod scc_enc;
 mod scc_parse;
-mod scc_parser;
 mod tttocea608;
 
 fn plugin_init(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
diff --git a/video/closedcaption/src/mcc_enc_headers.rs b/video/closedcaption/src/mcc_enc/headers.rs
index 6995c99c3..6995c99c3 100644
--- a/video/closedcaption/src/mcc_enc_headers.rs
+++ b/video/closedcaption/src/mcc_enc/headers.rs
diff --git a/video/closedcaption/src/mcc_enc.rs b/video/closedcaption/src/mcc_enc/imp.rs
index 6acfb3aab..9dac0fe28 100644
--- a/video/closedcaption/src/mcc_enc.rs
+++ b/video/closedcaption/src/mcc_enc/imp.rs
@@ -28,9 +28,7 @@ use uuid::Uuid;
 use std::io::Write;
 use std::sync::Mutex;
 
-#[path = "mcc_enc_headers.rs"]
-mod mcc_enc_headers;
-use self::mcc_enc_headers::*;
+use super::headers::*;
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 enum Format {
@@ -89,7 +87,7 @@ static PROPERTIES: [subclass::Property; 2] = [
     }),
 ];
 
-struct MccEnc {
+pub struct MccEnc {
     srcpad: gst::Pad,
     sinkpad: gst::Pad,
     state: Mutex<State>,
@@ -291,7 +289,7 @@ impl MccEnc {
 
     fn generate_caption(
         &self,
-        element: &gst::Element,
+        element: &super::MccEnc,
         state: &State,
         buffer: &gst::Buffer,
         outbuf: &mut Vec<u8>,
@@ -359,7 +357,7 @@ impl MccEnc {
     fn sink_chain(
         &self,
         pad: &gst::Pad,
-        element: &gst::Element,
+        element: &super::MccEnc,
         buffer: gst::Buffer,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
         gst_log!(CAT, obj: pad, "Handling buffer {:?}", buffer);
@@ -383,7 +381,7 @@ impl MccEnc {
         self.srcpad.push(buf)
     }
 
-    fn sink_event(&self, pad: &gst::Pad, element: &gst::Element, event: gst::Event) -> bool {
+    fn sink_event(&self, pad: &gst::Pad, element: &super::MccEnc, event: gst::Event) -> bool {
         use gst::EventView;
 
         gst_log!(CAT, obj: pad, "Handling event {:?}", event);
@@ -426,7 +424,7 @@ impl MccEnc {
         }
     }
 
-    fn src_event(&self, pad: &gst::Pad, element: &gst::Element, event: gst::Event) -> bool {
+    fn src_event(&self, pad: &gst::Pad, element: &super::MccEnc, event: gst::Event) -> bool {
         use gst::EventView;
 
         gst_log!(CAT, obj: pad, "Handling event {:?}", event);
@@ -439,7 +437,12 @@ impl MccEnc {
         }
     }
 
-    fn src_query(&self, pad: &gst::Pad, element: &gst::Element, query: &mut gst::QueryRef) -> bool {
+    fn src_query(
+        &self,
+        pad: &gst::Pad,
+        element: &super::MccEnc,
+        query: &mut gst::QueryRef,
+    ) -> bool {
         use gst::QueryView;
 
         gst_log!(CAT, obj: pad, "Handling query {:?}", query);
@@ -462,13 +465,14 @@ impl MccEnc {
 
 impl ObjectSubclass for MccEnc {
     const NAME: &'static str = "RsMccEnc";
+    type Type = super::MccEnc;
     type ParentType = gst::Element;
     type Instance = gst::subclass::ElementInstanceStruct<Self>;
     type Class = subclass::simple::ClassStruct<Self>;
 
     glib_object_subclass!();
 
-    fn with_class(klass: &subclass::simple::ClassStruct<Self>) -> Self {
+    fn with_class(klass: &Self::Class) -> Self {
         let templ = klass.get_pad_template("sink").unwrap();
         let sinkpad = gst::Pad::builder_with_template(&templ, Some("sink"))
             .chain_function(|pad, parent, buffer| {
@@ -513,7 +517,7 @@ impl ObjectSubclass for MccEnc {
         }
     }
 
-    fn class_init(klass: &mut subclass::simple::ClassStruct<Self>) {
+    fn class_init(klass: &mut Self::Class) {
         klass.set_metadata(
             "Mcc Encoder",
             "Encoder/ClosedCaption",
@@ -571,7 +575,7 @@ impl ObjectSubclass for MccEnc {
 }
 
 impl ObjectImpl for MccEnc {
-    fn set_property(&self, _obj: &glib::Object, id: usize, value: &glib::Value) {
+    fn set_property(&self, _obj: &Self::Type, id: usize, value: &glib::Value) {
         let prop = &PROPERTIES[id];
 
         match *prop {
@@ -587,7 +591,7 @@ impl ObjectImpl for MccEnc {
         }
     }
 
-    fn get_property(&self, _obj: &glib::Object, id: usize) -> Result<glib::Value, ()> {
+    fn get_property(&self, _obj: &Self::Type, id: usize) -> Result<glib::Value, ()> {
         let prop = &PROPERTIES[id];
 
         match *prop {
@@ -603,19 +607,18 @@ impl ObjectImpl for MccEnc {
         }
     }
 
-    fn constructed(&self, obj: &glib::Object) {
+    fn constructed(&self, obj: &Self::Type) {
         self.parent_constructed(obj);
 
-        let element = obj.downcast_ref::<gst::Element>().unwrap();
-        element.add_pad(&self.sinkpad).unwrap();
-        element.add_pad(&self.srcpad).unwrap();
+        obj.add_pad(&self.sinkpad).unwrap();
+        obj.add_pad(&self.srcpad).unwrap();
     }
 }
 
 impl ElementImpl for MccEnc {
     fn change_state(
         &self,
-        element: &gst::Element,
+        element: &Self::Type,
         transition: gst::StateChange,
     ) -> Result<gst::StateChangeSuccess, gst::StateChangeError> {
         gst_trace!(CAT, obj: element, "Changing state {:?}", transition);
@@ -632,12 +635,3 @@ impl ElementImpl for MccEnc {
         self.parent_change_state(element, transition)
     }
 }
-
-pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
-    gst::Element::register(
-        Some(plugin),
-        "mccenc",
-        gst::Rank::Primary,
-        MccEnc::get_type(),
-    )
-}
diff --git a/video/closedcaption/src/mcc_enc/mod.rs b/video/closedcaption/src/mcc_enc/mod.rs
new file mode 100644
index 000000000..f3c1f0d30
--- /dev/null
+++ b/video/closedcaption/src/mcc_enc/mod.rs
@@ -0,0 +1,39 @@
+// Copyright (C) 2018 Sebastian Dröge <sebastian@centricular.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 Street, Suite 500,
+// Boston, MA 02110-1335, USA.
+
+use glib::prelude::*;
+
+mod headers;
+mod imp;
+
+glib_wrapper! {
+    pub struct MccEnc(ObjectSubclass<imp::MccEnc>) @extends gst::Element, gst::Object;
+}
+
+// GStreamer elements need to be thread-safe. For the private implementation this is automatically
+// enforced but for the public wrapper type we need to specify this manually.
+unsafe impl Send for MccEnc {}
+unsafe impl Sync for MccEnc {}
+
+pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
+    gst::Element::register(
+        Some(plugin),
+        "mccenc",
+        gst::Rank::Primary,
+        MccEnc::static_type(),
+    )
+}
diff --git a/video/closedcaption/src/mcc_parse.rs b/video/closedcaption/src/mcc_parse/imp.rs
index 90304b2f7..1f93db5e8 100644
--- a/video/closedcaption/src/mcc_parse.rs
+++ b/video/closedcaption/src/mcc_parse/imp.rs
@@ -26,8 +26,8 @@ use std::cmp;
 use std::convert::TryInto;
 use std::sync::{Mutex, MutexGuard};
 
+use super::parser::{MccLine, MccParser, TimeCode};
 use crate::line_reader::LineReader;
-use crate::mcc_parser::{MccLine, MccParser, TimeCode};
 
 lazy_static! {
     static ref CAT: gst::DebugCategory = {
@@ -54,7 +54,7 @@ struct PullState {
 }
 
 impl PullState {
-    fn new(element: &gst::Element, pad: &gst::Pad) -> Self {
+    fn new(element: &super::MccParse, pad: &gst::Pad) -> Self {
         Self {
             need_stream_start: true,
             stream_id: pad
@@ -180,7 +180,7 @@ impl State {
 
     fn handle_timecode(
         &mut self,
-        element: &gst::Element,
+        element: &super::MccParse,
         framerate: gst::Fraction,
         drop_frame: bool,
         tc: TimeCode,
@@ -219,7 +219,7 @@ impl State {
     /// not produce timestamps jumping backwards
     fn update_timestamp(
         &mut self,
-        element: &gst::Element,
+        element: &super::MccParse,
         timecode: &gst_video::ValidVideoTimeCode,
     ) {
         let nsecs = gst::ClockTime::from(timecode.nsec_since_daily_jam());
@@ -255,7 +255,7 @@ impl State {
 
     fn add_buffer_metadata(
         &mut self,
-        element: &gst::Element,
+        element: &super::MccParse,
         buffer: &mut gst::buffer::Buffer,
         timecode: &gst_video::ValidVideoTimeCode,
         framerate: gst::Fraction,
@@ -281,7 +281,7 @@ impl State {
 
     fn create_events(
         &mut self,
-        element: &gst::Element,
+        element: &super::MccParse,
         format: Option<Format>,
         framerate: gst::Fraction,
     ) -> Vec<gst::Event> {
@@ -341,7 +341,7 @@ impl State {
     }
 }
 
-struct MccParse {
+pub struct MccParse {
     srcpad: gst::Pad,
     sinkpad: gst::Pad,
     state: Mutex<State>,
@@ -369,7 +369,7 @@ impl AsMut<[u8]> for OffsetVec {
 impl MccParse {
     fn handle_buffer(
         &self,
-        element: &gst::Element,
+        element: &super::MccParse,
         buffer: Option<gst::Buffer>,
         scan_tc_rate: bool,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
@@ -513,7 +513,7 @@ impl MccParse {
 
     fn handle_skipped_line(
         &self,
-        element: &gst::Element,
+        element: &super::MccParse,
         tc: TimeCode,
         mut state: MutexGuard<State>,
     ) -> Result<MutexGuard<State>, gst::FlowError> {
@@ -537,7 +537,7 @@ impl MccParse {
 
     fn handle_line(
         &self,
-        element: &gst::Element,
+        element: &super::MccParse,
         tc: TimeCode,
         data: Vec<u8>,
         format: Format,
@@ -587,7 +587,7 @@ impl MccParse {
     fn sink_activate(
         &self,
         pad: &gst::Pad,
-        element: &gst::Element,
+        element: &super::MccParse,
     ) -> Result<(), gst::LoggableError> {
         let mode = {
             let mut query = gst::query::Scheduling::new();
@@ -616,7 +616,7 @@ impl MccParse {
         Ok(())
     }
 
-    fn start_task(&self, element: &gst::Element) -> Result<(), gst::LoggableError> {
+    fn start_task(&self, element: &super::MccParse) -> Result<(), gst::LoggableError> {
         let element_weak = element.downgrade();
         let pad_weak = self.sinkpad.downgrade();
         let res = self.sinkpad.start_task(move || {
@@ -642,7 +642,7 @@ impl MccParse {
     fn sink_activatemode(
         &self,
         _pad: &gst::Pad,
-        element: &gst::Element,
+        element: &super::MccParse,
         mode: gst::PadMode,
         active: bool,
     ) -> Result<(), gst::LoggableError> {
@@ -659,7 +659,7 @@ impl MccParse {
 
     fn scan_duration(
         &self,
-        element: &gst::Element,
+        element: &super::MccParse,
     ) -> Result<Option<ValidVideoTimeCode>, gst::LoggableError> {
         gst_debug!(CAT, obj: element, "Scanning duration");
 
@@ -748,7 +748,7 @@ impl MccParse {
         }
     }
 
-    fn push_eos(&self, element: &gst::Element) {
+    fn push_eos(&self, element: &super::MccParse) {
         let mut state = self.state.lock().unwrap();
 
         if state.seeking {
@@ -784,7 +784,7 @@ impl MccParse {
         }
     }
 
-    fn loop_fn(&self, element: &gst::Element) {
+    fn loop_fn(&self, element: &super::MccParse) {
         let mut state = self.state.lock().unwrap();
         let State {
             timecode_rate: ref tc_rate,
@@ -882,7 +882,7 @@ impl MccParse {
     fn sink_chain(
         &self,
         pad: &gst::Pad,
-        element: &gst::Element,
+        element: &super::MccParse,
         buffer: gst::Buffer,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
         gst_log!(CAT, obj: pad, "Handling buffer {:?}", buffer);
@@ -910,7 +910,7 @@ impl MccParse {
         self.state.lock().unwrap()
     }
 
-    fn sink_event(&self, pad: &gst::Pad, element: &gst::Element, event: gst::Event) -> bool {
+    fn sink_event(&self, pad: &gst::Pad, element: &super::MccParse, event: gst::Event) -> bool {
         use gst::EventView;
 
         gst_log!(CAT, obj: pad, "Handling event {:?}", event);
@@ -956,7 +956,7 @@ impl MccParse {
         }
     }
 
-    fn perform_seek(&self, event: &gst::event::Seek, element: &gst::Element) -> bool {
+    fn perform_seek(&self, event: &gst::event::Seek, element: &super::MccParse) -> bool {
         let mut state = self.state.lock().unwrap();
 
         if state.pull.is_none() {
@@ -1049,7 +1049,7 @@ impl MccParse {
         }
     }
 
-    fn src_event(&self, pad: &gst::Pad, element: &gst::Element, event: gst::Event) -> bool {
+    fn src_event(&self, pad: &gst::Pad, element: &super::MccParse, event: gst::Event) -> bool {
         use gst::EventView;
 
         gst_log!(CAT, obj: pad, "Handling event {:?}", event);
@@ -1059,7 +1059,12 @@ impl MccParse {
         }
     }
 
-    fn src_query(&self, pad: &gst::Pad, element: &gst::Element, query: &mut gst::QueryRef) -> bool {
+    fn src_query(
+        &self,
+        pad: &gst::Pad,
+        element: &super::MccParse,
+        query: &mut gst::QueryRef,
+    ) -> bool {
         use gst::QueryView;
 
         gst_log!(CAT, obj: pad, "Handling query {:?}", query);
@@ -1120,13 +1125,14 @@ impl MccParse {
 
 impl ObjectSubclass for MccParse {
     const NAME: &'static str = "RsMccParse";
+    type Type = super::MccParse;
     type ParentType = gst::Element;
     type Instance = gst::subclass::ElementInstanceStruct<Self>;
     type Class = subclass::simple::ClassStruct<Self>;
 
     glib_object_subclass!();
 
-    fn with_class(klass: &subclass::simple::ClassStruct<Self>) -> Self {
+    fn with_class(klass: &Self::Class) -> Self {
         let templ = klass.get_pad_template("sink").unwrap();
         let sinkpad = gst::Pad::builder_with_template(&templ, Some("sink"))
             .activate_function(|pad, parent| {
@@ -1189,7 +1195,7 @@ impl ObjectSubclass for MccParse {
         }
     }
 
-    fn class_init(klass: &mut subclass::simple::ClassStruct<Self>) {
+    fn class_init(klass: &mut Self::Class) {
         klass.set_metadata(
             "Mcc Parse",
             "Parser/ClosedCaption",
@@ -1241,19 +1247,18 @@ impl ObjectSubclass for MccParse {
 }
 
 impl ObjectImpl for MccParse {
-    fn constructed(&self, obj: &glib::Object) {
+    fn constructed(&self, obj: &Self::Type) {
         self.parent_constructed(obj);
 
-        let element = obj.downcast_ref::<gst::Element>().unwrap();
-        element.add_pad(&self.sinkpad).unwrap();
-        element.add_pad(&self.srcpad).unwrap();
+        obj.add_pad(&self.sinkpad).unwrap();
+        obj.add_pad(&self.srcpad).unwrap();
     }
 }
 
 impl ElementImpl for MccParse {
     fn change_state(
         &self,
-        element: &gst::Element,
+        element: &Self::Type,
         transition: gst::StateChange,
     ) -> Result<gst::StateChangeSuccess, gst::StateChangeError> {
         gst_trace!(CAT, obj: element, "Changing state {:?}", transition);
@@ -1270,12 +1275,3 @@ impl ElementImpl for MccParse {
         self.parent_change_state(element, transition)
     }
 }
-
-pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
-    gst::Element::register(
-        Some(plugin),
-        "mccparse",
-        gst::Rank::Primary,
-        MccParse::get_type(),
-    )
-}
diff --git a/video/closedcaption/src/mcc_parse/mod.rs b/video/closedcaption/src/mcc_parse/mod.rs
new file mode 100644
index 000000000..d3ee283e0
--- /dev/null
+++ b/video/closedcaption/src/mcc_parse/mod.rs
@@ -0,0 +1,39 @@
+// Copyright (C) 2018 Sebastian Dröge <sebastian@centricular.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 Street, Suite 500,
+// Boston, MA 02110-1335, USA.
+
+use glib::prelude::*;
+
+mod imp;
+mod parser;
+
+glib_wrapper! {
+    pub struct MccParse(ObjectSubclass<imp::MccParse>) @extends gst::Element, gst::Object;
+}
+
+// GStreamer elements need to be thread-safe. For the private implementation this is automatically
+// enforced but for the public wrapper type we need to specify this manually.
+unsafe impl Send for MccParse {}
+unsafe impl Sync for MccParse {}
+
+pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
+    gst::Element::register(
+        Some(plugin),
+        "mccparse",
+        gst::Rank::Primary,
+        MccParse::static_type(),
+    )
+}
diff --git a/video/closedcaption/src/mcc_parser.rs b/video/closedcaption/src/mcc_parse/parser.rs
index c2ec97069..b57e95e44 100644
--- a/video/closedcaption/src/mcc_parser.rs
+++ b/video/closedcaption/src/mcc_parse/parser.rs
@@ -752,7 +752,7 @@ mod tests {
 
     #[test]
     fn test_parser() {
-        let mcc_file = include_bytes!("../tests/captions-test_708.mcc");
+        let mcc_file = include_bytes!("../../tests/captions-test_708.mcc");
         let mut reader = crate::line_reader::LineReader::new();
         let mut parser = MccParser::new();
         let mut line_cnt = 0;
diff --git a/video/closedcaption/src/scc_enc.rs b/video/closedcaption/src/scc_enc/imp.rs
index 00b3bf85e..c9c473931 100644
--- a/video/closedcaption/src/scc_enc.rs
+++ b/video/closedcaption/src/scc_enc/imp.rs
@@ -16,7 +16,6 @@
 // Free Software Foundation, Inc., 51 Franklin Street, Suite 500,
 // Boston, MA 02110-1335, USA.
 
-use glib::prelude::*;
 use glib::subclass;
 use glib::subclass::prelude::*;
 use gst::prelude::*;
@@ -70,7 +69,7 @@ impl State {
 
     fn generate_caption(
         &mut self,
-        element: &gst::Element,
+        element: &super::SccEnc,
         buffer: gst::Buffer,
     ) -> Result<Option<gst::Buffer>, gst::FlowError> {
         // Arbitrary number that was chosen to keep in order
@@ -141,7 +140,7 @@ impl State {
     // Flush the internal buffers into a line
     fn write_line(
         &mut self,
-        element: &gst::Element,
+        element: &super::SccEnc,
     ) -> Result<Option<gst::Buffer>, gst::FlowError> {
         let mut outbuf = Vec::new();
         let mut line_start = true;
@@ -218,7 +217,7 @@ impl State {
     }
 }
 
-struct SccEnc {
+pub struct SccEnc {
     srcpad: gst::Pad,
     sinkpad: gst::Pad,
     state: Mutex<State>,
@@ -228,7 +227,7 @@ impl SccEnc {
     fn sink_chain(
         &self,
         pad: &gst::Pad,
-        element: &gst::Element,
+        element: &super::SccEnc,
         buffer: gst::Buffer,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
         gst_log!(CAT, obj: pad, "Handling buffer {:?}", buffer);
@@ -246,7 +245,7 @@ impl SccEnc {
         Ok(gst::FlowSuccess::Ok)
     }
 
-    fn sink_event(&self, pad: &gst::Pad, element: &gst::Element, event: gst::Event) -> bool {
+    fn sink_event(&self, pad: &gst::Pad, element: &super::SccEnc, event: gst::Event) -> bool {
         use gst::EventView;
 
         gst_log!(CAT, obj: pad, "Handling event {:?}", event);
@@ -294,7 +293,7 @@ impl SccEnc {
         }
     }
 
-    fn src_event(&self, pad: &gst::Pad, element: &gst::Element, event: gst::Event) -> bool {
+    fn src_event(&self, pad: &gst::Pad, element: &super::SccEnc, event: gst::Event) -> bool {
         use gst::EventView;
 
         gst_log!(CAT, obj: pad, "Handling event {:?}", event);
@@ -307,7 +306,12 @@ impl SccEnc {
         }
     }
 
-    fn src_query(&self, pad: &gst::Pad, element: &gst::Element, query: &mut gst::QueryRef) -> bool {
+    fn src_query(
+        &self,
+        pad: &gst::Pad,
+        element: &super::SccEnc,
+        query: &mut gst::QueryRef,
+    ) -> bool {
         use gst::QueryView;
 
         gst_log!(CAT, obj: pad, "Handling query {:?}", query);
@@ -330,13 +334,14 @@ impl SccEnc {
 
 impl ObjectSubclass for SccEnc {
     const NAME: &'static str = "RsSccEnc";
+    type Type = super::SccEnc;
     type ParentType = gst::Element;
     type Instance = gst::subclass::ElementInstanceStruct<Self>;
     type Class = subclass::simple::ClassStruct<Self>;
 
     glib_object_subclass!();
 
-    fn with_class(klass: &subclass::simple::ClassStruct<Self>) -> Self {
+    fn with_class(klass: &Self::Class) -> Self {
         let templ = klass.get_pad_template("sink").unwrap();
         let sinkpad = gst::Pad::builder_with_template(&templ, Some("sink"))
             .chain_function(|pad, parent, buffer| {
@@ -380,7 +385,7 @@ impl ObjectSubclass for SccEnc {
         }
     }
 
-    fn class_init(klass: &mut subclass::simple::ClassStruct<Self>) {
+    fn class_init(klass: &mut Self::Class) {
         klass.set_metadata(
             "Scc Encoder",
             "Encoder/ClosedCaption",
@@ -416,19 +421,18 @@ impl ObjectSubclass for SccEnc {
 }
 
 impl ObjectImpl for SccEnc {
-    fn constructed(&self, obj: &glib::Object) {
+    fn constructed(&self, obj: &Self::Type) {
         self.parent_constructed(obj);
 
-        let element = obj.downcast_ref::<gst::Element>().unwrap();
-        element.add_pad(&self.sinkpad).unwrap();
-        element.add_pad(&self.srcpad).unwrap();
+        obj.add_pad(&self.sinkpad).unwrap();
+        obj.add_pad(&self.srcpad).unwrap();
     }
 }
 
 impl ElementImpl for SccEnc {
     fn change_state(
         &self,
-        element: &gst::Element,
+        element: &Self::Type,
         transition: gst::StateChange,
     ) -> Result<gst::StateChangeSuccess, gst::StateChangeError> {
         gst_trace!(CAT, obj: element, "Changing state {:?}", transition);
@@ -445,12 +449,3 @@ impl ElementImpl for SccEnc {
         self.parent_change_state(element, transition)
     }
 }
-
-pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
-    gst::Element::register(
-        Some(plugin),
-        "sccenc",
-        gst::Rank::Primary,
-        SccEnc::get_type(),
-    )
-}
diff --git a/video/closedcaption/src/scc_enc/mod.rs b/video/closedcaption/src/scc_enc/mod.rs
new file mode 100644
index 000000000..46998d753
--- /dev/null
+++ b/video/closedcaption/src/scc_enc/mod.rs
@@ -0,0 +1,39 @@
+// Copyright (C) 2019 Sebastian Dröge <sebastian@centricular.com>
+// Copyright (C) 2019 Jordan Petridis <jordan@centricular.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 Street, Suite 500,
+// Boston, MA 02110-1335, USA.
+
+use glib::prelude::*;
+
+mod imp;
+
+glib_wrapper! {
+    pub struct SccEnc(ObjectSubclass<imp::SccEnc>) @extends gst::Element, gst::Object;
+}
+
+// GStreamer elements need to be thread-safe. For the private implementation this is automatically
+// enforced but for the public wrapper type we need to specify this manually.
+unsafe impl Send for SccEnc {}
+unsafe impl Sync for SccEnc {}
+
+pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
+    gst::Element::register(
+        Some(plugin),
+        "sccenc",
+        gst::Rank::Primary,
+        SccEnc::static_type(),
+    )
+}
diff --git a/video/closedcaption/src/scc_parse.rs b/video/closedcaption/src/scc_parse/imp.rs
index 1b70bc015..5e2781ec3 100644
--- a/video/closedcaption/src/scc_parse.rs
+++ b/video/closedcaption/src/scc_parse/imp.rs
@@ -16,7 +16,6 @@
 // Free Software Foundation, Inc., 51 Franklin Street, Suite 500,
 // Boston, MA 02110-1335, USA.
 
-use glib::prelude::*;
 use glib::subclass;
 use glib::subclass::prelude::*;
 use gst::prelude::*;
@@ -24,8 +23,8 @@ use gst::subclass::prelude::*;
 
 use std::sync::{Mutex, MutexGuard};
 
+use super::parser::{SccLine, SccParser, TimeCode};
 use crate::line_reader::LineReader;
-use crate::scc_parser::{SccLine, SccParser, TimeCode};
 
 lazy_static! {
     static ref CAT: gst::DebugCategory = {
@@ -83,7 +82,7 @@ impl State {
         &mut self,
         tc: TimeCode,
         framerate: gst::Fraction,
-        element: &gst::Element,
+        element: &super::SccParse,
     ) -> Result<gst_video::ValidVideoTimeCode, gst::FlowError> {
         use std::convert::TryInto;
 
@@ -137,7 +136,7 @@ impl State {
     fn update_timestamp(
         &mut self,
         timecode: &gst_video::ValidVideoTimeCode,
-        element: &gst::Element,
+        element: &super::SccParse,
     ) {
         let nsecs = gst::ClockTime::from(timecode.nsec_since_daily_jam());
 
@@ -159,7 +158,7 @@ impl State {
         buffer: &mut gst::buffer::Buffer,
         timecode: &gst_video::ValidVideoTimeCode,
         framerate: gst::Fraction,
-        element: &gst::Element,
+        element: &super::SccParse,
     ) {
         let buffer = buffer.get_mut().unwrap();
         gst_video::VideoTimeCodeMeta::add(buffer, &timecode);
@@ -175,7 +174,7 @@ impl State {
     }
 }
 
-struct SccParse {
+pub struct SccParse {
     srcpad: gst::Pad,
     sinkpad: gst::Pad,
     state: Mutex<State>,
@@ -184,7 +183,7 @@ struct SccParse {
 impl SccParse {
     fn handle_buffer(
         &self,
-        element: &gst::Element,
+        element: &super::SccParse,
         buffer: Option<gst::Buffer>,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
         let mut state = self.state.lock().unwrap();
@@ -234,7 +233,7 @@ impl SccParse {
         &self,
         tc: TimeCode,
         data: Vec<u8>,
-        element: &gst::Element,
+        element: &super::SccParse,
         mut state: MutexGuard<State>,
     ) -> Result<MutexGuard<State>, gst::FlowError> {
         gst_trace!(
@@ -309,7 +308,7 @@ impl SccParse {
     fn sink_chain(
         &self,
         pad: &gst::Pad,
-        element: &gst::Element,
+        element: &super::SccParse,
         buffer: gst::Buffer,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
         gst_log!(CAT, obj: pad, "Handling buffer {:?}", buffer);
@@ -317,7 +316,7 @@ impl SccParse {
         self.handle_buffer(element, Some(buffer))
     }
 
-    fn sink_event(&self, pad: &gst::Pad, element: &gst::Element, event: gst::Event) -> bool {
+    fn sink_event(&self, pad: &gst::Pad, element: &super::SccParse, event: gst::Event) -> bool {
         use gst::EventView;
 
         gst_log!(CAT, obj: pad, "Handling event {:?}", event);
@@ -367,7 +366,7 @@ impl SccParse {
         }
     }
 
-    fn src_event(&self, pad: &gst::Pad, element: &gst::Element, event: gst::Event) -> bool {
+    fn src_event(&self, pad: &gst::Pad, element: &super::SccParse, event: gst::Event) -> bool {
         use gst::EventView;
 
         gst_log!(CAT, obj: pad, "Handling event {:?}", event);
@@ -380,7 +379,12 @@ impl SccParse {
         }
     }
 
-    fn src_query(&self, pad: &gst::Pad, element: &gst::Element, query: &mut gst::QueryRef) -> bool {
+    fn src_query(
+        &self,
+        pad: &gst::Pad,
+        element: &super::SccParse,
+        query: &mut gst::QueryRef,
+    ) -> bool {
         use gst::QueryView;
 
         gst_log!(CAT, obj: pad, "Handling query {:?}", query);
@@ -413,13 +417,14 @@ impl SccParse {
 
 impl ObjectSubclass for SccParse {
     const NAME: &'static str = "RsSccParse";
+    type Type = super::SccParse;
     type ParentType = gst::Element;
     type Instance = gst::subclass::ElementInstanceStruct<Self>;
     type Class = subclass::simple::ClassStruct<Self>;
 
     glib_object_subclass!();
 
-    fn with_class(klass: &subclass::simple::ClassStruct<Self>) -> Self {
+    fn with_class(klass: &Self::Class) -> Self {
         let templ = klass.get_pad_template("sink").unwrap();
         let sinkpad = gst::Pad::builder_with_template(&templ, Some("sink"))
             .chain_function(|pad, parent, buffer| {
@@ -463,7 +468,7 @@ impl ObjectSubclass for SccParse {
         }
     }
 
-    fn class_init(klass: &mut subclass::simple::ClassStruct<Self>) {
+    fn class_init(klass: &mut Self::Class) {
         klass.set_metadata(
             "Scc Parse",
             "Parser/ClosedCaption",
@@ -500,19 +505,18 @@ impl ObjectSubclass for SccParse {
 }
 
 impl ObjectImpl for SccParse {
-    fn constructed(&self, obj: &glib::Object) {
+    fn constructed(&self, obj: &Self::Type) {
         self.parent_constructed(obj);
 
-        let element = obj.downcast_ref::<gst::Element>().unwrap();
-        element.add_pad(&self.sinkpad).unwrap();
-        element.add_pad(&self.srcpad).unwrap();
+        obj.add_pad(&self.sinkpad).unwrap();
+        obj.add_pad(&self.srcpad).unwrap();
     }
 }
 
 impl ElementImpl for SccParse {
     fn change_state(
         &self,
-        element: &gst::Element,
+        element: &Self::Type,
         transition: gst::StateChange,
     ) -> Result<gst::StateChangeSuccess, gst::StateChangeError> {
         gst_trace!(CAT, obj: element, "Changing state {:?}", transition);
@@ -529,12 +533,3 @@ impl ElementImpl for SccParse {
         self.parent_change_state(element, transition)
     }
 }
-
-pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
-    gst::Element::register(
-        Some(plugin),
-        "sccparse",
-        gst::Rank::Primary,
-        SccParse::get_type(),
-    )
-}
diff --git a/video/closedcaption/src/scc_parse/mod.rs b/video/closedcaption/src/scc_parse/mod.rs
new file mode 100644
index 000000000..19cf93f87
--- /dev/null
+++ b/video/closedcaption/src/scc_parse/mod.rs
@@ -0,0 +1,40 @@
+// Copyright (C) 2019 Sebastian Dröge <sebastian@centricular.com>
+// Copyright (C) 2019 Jordan Petridis <jordan@centricular.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 Street, Suite 500,
+// Boston, MA 02110-1335, USA.
+
+use glib::prelude::*;
+
+mod imp;
+mod parser;
+
+glib_wrapper! {
+    pub struct SccParse(ObjectSubclass<imp::SccParse>) @extends gst::Element, gst::Object;
+}
+
+// GStreamer elements need to be thread-safe. For the private implementation this is automatically
+// enforced but for the public wrapper type we need to specify this manually.
+unsafe impl Send for SccParse {}
+unsafe impl Sync for SccParse {}
+
+pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
+    gst::Element::register(
+        Some(plugin),
+        "sccparse",
+        gst::Rank::Primary,
+        SccParse::static_type(),
+    )
+}
diff --git a/video/closedcaption/src/scc_parser.rs b/video/closedcaption/src/scc_parse/parser.rs
index bd02f3e94..7aff8848a 100644
--- a/video/closedcaption/src/scc_parser.rs
+++ b/video/closedcaption/src/scc_parse/parser.rs
@@ -455,7 +455,7 @@ mod tests {
 
     #[test]
     fn test_parser() {
-        let scc_file = include_bytes!("../tests/dn2018-1217.scc");
+        let scc_file = include_bytes!("../../tests/dn2018-1217.scc");
         let mut reader = crate::line_reader::LineReader::new();
         let mut parser = SccParser::new();
         let mut line_cnt = 0;
diff --git a/video/closedcaption/src/tttocea608.rs b/video/closedcaption/src/tttocea608/imp.rs
index 935f04ea6..beb05e82a 100644
--- a/video/closedcaption/src/tttocea608.rs
+++ b/video/closedcaption/src/tttocea608/imp.rs
@@ -18,13 +18,14 @@
 use glib::prelude::*;
 use glib::subclass;
 use glib::subclass::prelude::*;
-use glib::GEnum;
 use gst::prelude::*;
 use gst::subclass::prelude::*;
 
-use super::cea608tott_ffi as ffi;
+use crate::ffi;
 use std::sync::Mutex;
 
+use super::Mode;
+
 fn decrement_pts(
     min_frame_no: u64,
     frame_no: &mut u64,
@@ -208,16 +209,6 @@ const DEFAULT_FPS_D: i32 = 1;
  */
 const LATENCY_BUFFERS: u64 = 74;
 
-#[derive(Debug, Eq, PartialEq, Ord, PartialOrd, Hash, Clone, Copy, GEnum)]
-#[repr(u32)]
-#[genum(type_name = "GstTtToCea608Mode")]
-enum Mode {
-    PopOn,
-    RollUp2,
-    RollUp3,
-    RollUp4,
-}
-
 const DEFAULT_MODE: Mode = Mode::RollUp2;
 
 static PROPERTIES: [subclass::Property; 1] = [subclass::Property("mode", |name| {
@@ -264,7 +255,7 @@ impl Default for State {
     }
 }
 
-struct TtToCea608 {
+pub struct TtToCea608 {
     srcpad: gst::Pad,
     sinkpad: gst::Pad,
 
@@ -346,7 +337,7 @@ impl TtToCea608 {
     fn sink_chain(
         &self,
         pad: &gst::Pad,
-        element: &gst::Element,
+        element: &super::TtToCea608,
         buffer: gst::Buffer,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
         let pts = match buffer.get_pts() {
@@ -628,7 +619,12 @@ impl TtToCea608 {
         }
     }
 
-    fn src_query(&self, pad: &gst::Pad, element: &gst::Element, query: &mut gst::QueryRef) -> bool {
+    fn src_query(
+        &self,
+        pad: &gst::Pad,
+        element: &super::TtToCea608,
+        query: &mut gst::QueryRef,
+    ) -> bool {
         use gst::QueryView;
 
         gst_log!(CAT, obj: pad, "Handling query {:?}", query);
@@ -671,7 +667,7 @@ impl TtToCea608 {
         }
     }
 
-    fn sink_event(&self, pad: &gst::Pad, element: &gst::Element, event: gst::Event) -> bool {
+    fn sink_event(&self, pad: &gst::Pad, element: &super::TtToCea608, event: gst::Event) -> bool {
         gst_log!(CAT, obj: pad, "Handling event {:?}", event);
 
         use gst::EventView;
@@ -785,13 +781,14 @@ impl TtToCea608 {
 
 impl ObjectSubclass for TtToCea608 {
     const NAME: &'static str = "TtToCea608";
+    type Type = super::TtToCea608;
     type ParentType = gst::Element;
     type Instance = gst::subclass::ElementInstanceStruct<Self>;
     type Class = subclass::simple::ClassStruct<Self>;
 
     glib_object_subclass!();
 
-    fn with_class(klass: &subclass::simple::ClassStruct<Self>) -> Self {
+    fn with_class(klass: &Self::Class) -> Self {
         let templ = klass.get_pad_template("sink").unwrap();
         let sinkpad = gst::Pad::builder_with_template(&templ, Some("sink"))
             .chain_function(|pad, parent, buffer| {
@@ -831,7 +828,7 @@ impl ObjectSubclass for TtToCea608 {
         }
     }
 
-    fn class_init(klass: &mut subclass::simple::ClassStruct<Self>) {
+    fn class_init(klass: &mut Self::Class) {
         klass.set_metadata(
             "TT to CEA-608",
             "Generic",
@@ -874,15 +871,14 @@ impl ObjectSubclass for TtToCea608 {
 }
 
 impl ObjectImpl for TtToCea608 {
-    fn constructed(&self, obj: &glib::Object) {
+    fn constructed(&self, obj: &Self::Type) {
         self.parent_constructed(obj);
 
-        let element = obj.downcast_ref::<gst::Element>().unwrap();
-        element.add_pad(&self.sinkpad).unwrap();
-        element.add_pad(&self.srcpad).unwrap();
+        obj.add_pad(&self.sinkpad).unwrap();
+        obj.add_pad(&self.srcpad).unwrap();
     }
 
-    fn set_property(&self, _obj: &glib::Object, id: usize, value: &glib::Value) {
+    fn set_property(&self, _obj: &Self::Type, id: usize, value: &glib::Value) {
         let prop = &PROPERTIES[id];
 
         match *prop {
@@ -894,7 +890,7 @@ impl ObjectImpl for TtToCea608 {
         }
     }
 
-    fn get_property(&self, _obj: &glib::Object, id: usize) -> Result<glib::Value, ()> {
+    fn get_property(&self, _obj: &Self::Type, id: usize) -> Result<glib::Value, ()> {
         let prop = &PROPERTIES[id];
 
         match *prop {
@@ -910,7 +906,7 @@ impl ObjectImpl for TtToCea608 {
 impl ElementImpl for TtToCea608 {
     fn change_state(
         &self,
-        element: &gst::Element,
+        element: &Self::Type,
         transition: gst::StateChange,
     ) -> Result<gst::StateChangeSuccess, gst::StateChangeError> {
         gst_trace!(CAT, obj: element, "Changing state {:?}", transition);
@@ -941,12 +937,3 @@ impl ElementImpl for TtToCea608 {
         Ok(ret)
     }
 }
-
-pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
-    gst::Element::register(
-        Some(plugin),
-        "tttocea608",
-        gst::Rank::None,
-        TtToCea608::get_type(),
-    )
-}
diff --git a/video/closedcaption/src/tttocea608/mod.rs b/video/closedcaption/src/tttocea608/mod.rs
new file mode 100644
index 000000000..790e71511
--- /dev/null
+++ b/video/closedcaption/src/tttocea608/mod.rs
@@ -0,0 +1,49 @@
+// Copyright (C) 2020 Mathieu Duponchelle <mathieu@centricular.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 Street, Suite 500,
+// Boston, MA 02110-1335, USA.
+
+use glib::prelude::*;
+use glib::GEnum;
+
+mod imp;
+
+#[derive(Debug, Eq, PartialEq, Ord, PartialOrd, Hash, Clone, Copy, GEnum)]
+#[repr(u32)]
+#[genum(type_name = "GstTtToCea608Mode")]
+enum Mode {
+    PopOn,
+    RollUp2,
+    RollUp3,
+    RollUp4,
+}
+
+glib_wrapper! {
+    pub struct TtToCea608(ObjectSubclass<imp::TtToCea608>) @extends gst::Element, gst::Object;
+}
+
+// GStreamer elements need to be thread-safe. For the private implementation this is automatically
+// enforced but for the public wrapper type we need to specify this manually.
+unsafe impl Send for TtToCea608 {}
+unsafe impl Sync for TtToCea608 {}
+
+pub fn register(plugin: &gst::Plugin) -> Result<(), glib::BoolError> {
+    gst::Element::register(
+        Some(plugin),
+        "tttocea608",
+        gst::Rank::None,
+        TtToCea608::static_type(),
+    )
+}