Add textoverlay element that was previously in the sandbox

Original commit message from CVS:
Add textoverlay element that was previously in the sandbox

3 files changed, 684 insertions, 2 deletions

diff --git a/ext/pango/Makefile.am b/ext/pango/Makefile.am
index ff6c2aba..5304729a 100644
--- a/ext/pango/Makefile.am
+++ b/ext/pango/Makefile.am
@@ -3,12 +3,16 @@ plugindir = $(libdir)/gstreamer-@GST_MAJORMINOR@
 #PANGO_CFLAGS = -I/usr/include/pango-1.0 -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include -I/usr/include/freetype2
 #PANGO_LDFLAGS = -Wl,--export-dynamic -lpangoft2-1.0 -lpango-1.0 -lgobject-2.0 -lgmodule-2.0 -ldl -lglib-2.0
 
-plugin_LTLIBRARIES = libgsttimeoverlay.la
+plugin_LTLIBRARIES = libgsttimeoverlay.la libgsttextoverlay.la
 
-noinst_HEADERS = gsttimeoverlay.h
+noinst_HEADERS = gsttimeoverlay.h gsttextoverlay.h
 
 libgsttimeoverlay_la_SOURCES = gsttimeoverlay.c
 libgsttimeoverlay_la_CFLAGS = $(GST_CFLAGS) $(PANGO_CFLAGS) -I$(top_srcdir)/gst/videofilter
 libgsttimeoverlay_la_LIBADD =
 libgsttimeoverlay_la_LDFLAGS = $(GST_PLUGIN_LDFLAGS) $(PANGO_LIBS) -lm
 
+libgsttextoverlay_la_SOURCES = gsttextoverlay.c
+libgsttextoverlay_la_CFLAGS = $(GST_CFLAGS) $(PANGO_CFLAGS)
+libgsttextoverlay_la_LIBADD =
+libgsttextoverlay_la_LDFLAGS = $(GST_PLUGIN_LDFLAGS) $(PANGO_LIBS)
diff --git a/ext/pango/gsttextoverlay.c b/ext/pango/gsttextoverlay.c
new file mode 100644
index 00000000..2ed90899
--- /dev/null
+++ b/ext/pango/gsttextoverlay.c
@@ -0,0 +1,607 @@
+
+
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+#include <gst/gst.h>
+#include "gsttextoverlay.h"
+//#include "gsttexttestsrc.h"
+//#include "gstsubparse.h"
+//#include "SDL_blit.h"
+
+static GstElementDetails textoverlay_details = {
+    "Text Overlay",
+    "Filter/Video",
+    "LGPL",
+    "Adds text strings on top of a video buffer",
+    VERSION, 
+    "Gustavo J. A. M. Carneiro <gjc@inescporto.pt>",
+    "(C) 2003",
+};
+
+
+
+enum {
+    ARG_0,
+    ARG_TEXT, 
+    ARG_VALIGN, 
+    ARG_HALIGN, 
+    ARG_X0, 
+    ARG_Y0, 
+    ARG_FONT_DESC, 
+};
+
+
+GST_PAD_TEMPLATE_FACTORY(textoverlay_src_template_factory,
+			 "src",
+			 GST_PAD_SRC,
+			 GST_PAD_ALWAYS,
+			 GST_CAPS_NEW(
+			     "textoverlay_src",
+			     "video/raw",
+			     "format",		GST_PROPS_LIST(
+				 GST_PROPS_FOURCC(GST_STR_FOURCC("I420"))
+				 ),
+			     "width", 		GST_PROPS_INT_RANGE(0, G_MAXINT), 
+			     "height",		GST_PROPS_INT_RANGE(0, G_MAXINT)
+			     )
+    )
+
+GST_PAD_TEMPLATE_FACTORY(video_sink_template_factory,
+			 "video_sink",
+			 GST_PAD_SINK,
+			 GST_PAD_ALWAYS,
+			 GST_CAPS_NEW(
+			     "video_sink",
+			     "video/raw",
+			     "format",		GST_PROPS_LIST(
+				 GST_PROPS_FOURCC(GST_STR_FOURCC("I420"))
+				 ),
+			     "width", 		GST_PROPS_INT_RANGE(0, G_MAXINT),
+			     "height",		GST_PROPS_INT_RANGE(0, G_MAXINT)
+			     )
+    )
+
+GST_PAD_TEMPLATE_FACTORY(text_sink_template_factory,
+			 "text_sink",
+			 GST_PAD_SINK,
+			 GST_PAD_ALWAYS,
+			 GST_CAPS_NEW(
+			     "text_sink",
+			     "text/x-pango-markup", 
+			     NULL
+			     )
+    )
+
+static void                  gst_textoverlay_class_init(GstTextOverlayClass *klass);
+static void                  gst_textoverlay_init(GstTextOverlay      *overlay);
+static void                  gst_textoverlay_set_property(GObject             *object, 
+							   guint                prop_id, 
+							   const GValue        *value, 
+							   GParamSpec          *pspec);
+static void                  gst_textoverlay_get_property(GObject             *object, 
+							   guint                prop_id, 
+							   GValue              *value, 
+							   GParamSpec          *pspec);
+static GstElementStateReturn gst_textoverlay_change_state(GstElement          *element);
+static void                  gst_textoverlay_finalize(GObject             *object);
+
+
+static GstElementClass *parent_class = NULL;
+/*static guint gst_textoverlay_signals[LAST_SIGNAL] = { 0 }; */
+
+
+GType
+gst_textoverlay_get_type(void)
+{
+    static GType textoverlay_type = 0;
+
+    if (!textoverlay_type) {
+	static const GTypeInfo textoverlay_info = {
+	    sizeof(GstTextOverlayClass), 
+	    NULL,
+	    NULL,
+	    (GClassInitFunc)gst_textoverlay_class_init,
+	    NULL,
+	    NULL,
+	    sizeof(GstTextOverlay),
+	    0,
+	    (GInstanceInitFunc)gst_textoverlay_init,
+	};
+	textoverlay_type = g_type_register_static(GST_TYPE_ELEMENT, "GstTextOverlay", 
+						  &textoverlay_info, 0);
+    }
+    return textoverlay_type;
+}
+
+
+static void
+gst_textoverlay_class_init(GstTextOverlayClass *klass)
+{
+    GObjectClass *gobject_class;
+    GstElementClass *gstelement_class;
+
+    gobject_class = (GObjectClass*)klass;
+    gstelement_class = (GstElementClass*)klass;
+
+    parent_class = g_type_class_peek_parent(klass);
+
+    gobject_class->finalize = gst_textoverlay_finalize;
+    gobject_class->set_property = gst_textoverlay_set_property;
+    gobject_class->get_property = gst_textoverlay_get_property;
+
+    gstelement_class->change_state = gst_textoverlay_change_state;
+    klass->pango_context = pango_ft2_get_context(72, 72);
+    g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_TEXT, 
+				    g_param_spec_string("text", "text", 
+							"Text to be display,"
+							" in pango markup format.", 
+							"", G_PARAM_WRITABLE));
+    g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_VALIGN, 
+				    g_param_spec_string("valign", "vertical alignment", 
+							"Vertical alignment of the text. "
+							"Can be either 'baseline', 'bottom', or 'top'", 
+							"baseline", G_PARAM_WRITABLE));
+    g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_HALIGN, 
+				    g_param_spec_string("halign", "horizontal alignment", 
+							"Horizontal alignment of the text. "
+							"Can be either 'left', 'right', or 'center'", 
+							"center", G_PARAM_WRITABLE));
+    g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_X0, 
+				    g_param_spec_int("x0", "X position", 
+						     "Initial X position."
+						     " Horizontal aligment takes this point"
+						     " as reference.", 
+						     G_MININT, G_MAXINT, 0, G_PARAM_WRITABLE));
+    g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_Y0, 
+				    g_param_spec_int("y0", "Y position", 
+						     "Initial Y position."
+						     " Vertical aligment takes this point"
+						     " as reference.", 
+						     G_MININT, G_MAXINT, 0, G_PARAM_WRITABLE));
+    g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_FONT_DESC, 
+				    g_param_spec_string("font-desc", "font description", 
+							"Pango font description of font "
+							"to be used for rendering. "
+							"See documentation of "
+							"pango_font_description_from_string"
+							" for syntax.", 
+							"", G_PARAM_WRITABLE));
+}
+
+
+static void
+resize_bitmap(GstTextOverlay *overlay, int width, int height)
+{
+    FT_Bitmap *bitmap = &overlay->bitmap;
+    int        pitch = (width|3) + 1;
+    int        size = pitch*height;
+
+    /* no need to keep reallocating; just keep the maximum size so far */
+    if (size <= overlay->bitmap_buffer_size) {
+	bitmap->rows = height;
+	bitmap->width = width;
+	bitmap->pitch = pitch;
+	memset(bitmap->buffer, 0, overlay->bitmap_buffer_size);
+	return;
+    }
+    if (!bitmap->buffer) {
+	/* initialize */
+	bitmap->pixel_mode = FT_PIXEL_MODE_GRAY;
+	bitmap->num_grays = 256;
+    }
+    if (bitmap->buffer)
+	bitmap->buffer = g_realloc(bitmap->buffer, size);
+    else
+	bitmap->buffer = g_malloc(size);
+    bitmap->rows = height;
+    bitmap->width = width;
+    bitmap->pitch = pitch;
+    memset(bitmap->buffer, 0, size);
+    overlay->bitmap_buffer_size = size;
+}
+
+static void
+render_text(GstTextOverlay *overlay)
+{
+    PangoRectangle ink_rect, logical_rect;
+
+    pango_layout_get_pixel_extents(overlay->layout, &ink_rect, &logical_rect);
+    resize_bitmap(overlay, ink_rect.width, ink_rect.height + ink_rect.y);
+    pango_ft2_render_layout(&overlay->bitmap, overlay->layout, 0, 0);
+    overlay->baseline_y = ink_rect.y;
+}
+
+/* static GstPadLinkReturn */
+/* gst_textoverlay_text_sinkconnect (GstPad *pad, GstCaps *caps) */
+/* { */
+/*     return GST_PAD_LINK_DONE; */
+/* } */
+
+
+static GstPadLinkReturn
+gst_textoverlay_video_sinkconnect(GstPad *pad, GstCaps *caps)
+{
+    GstTextOverlay *overlay;
+
+    overlay = GST_TEXTOVERLAY(gst_pad_get_parent(pad));
+
+    if (!GST_CAPS_IS_FIXED(caps))
+	return GST_PAD_LINK_DELAYED;
+
+    overlay->width = overlay->height = 0;
+    gst_caps_get_int(caps, "width", &overlay->width);
+    gst_caps_get_int(caps, "height", &overlay->height);
+
+    return gst_pad_try_set_caps(overlay->srcpad, caps);
+}
+
+
+static void
+gst_text_overlay_blit_yuv420(GstTextOverlay *overlay, FT_Bitmap *bitmap,
+			     guchar *pixbuf, int x0, int y0)
+{
+    int y;			/* text bitmap coordinates */
+    int x1, y1;			/* video buffer coordinates */
+    int rowinc, bit_rowinc, uv_rowinc;
+    guchar *p, *bitp, *u_p;
+    int video_width = overlay->width, video_height = overlay->height;
+    int bitmap_x0 = x0 < 1? -(x0 - 1) : 1; /* 1 pixel border */
+    int bitmap_y0 = y0 < 1? -(y0 - 1) : 1; /* 1 pixel border */
+    int bitmap_width = bitmap->width - bitmap_x0;
+    int bitmap_height = bitmap->rows - bitmap_y0;
+    int u_plane_size;
+    int skip_y, skip_x;
+    guchar v;
+
+    if (x0 + bitmap_x0 + bitmap_width > video_width - 1) /* 1 pixel border */
+	bitmap_width -= x0 + bitmap_x0 + bitmap_width - video_width + 1;
+    if (y0 + bitmap_y0 + bitmap_height > video_height - 1) /* 1 pixel border */
+	bitmap_height -= y0 + bitmap_y0 + bitmap_height - video_height + 1;
+
+    rowinc = video_width - bitmap_width;
+    uv_rowinc = video_width / 2 - bitmap_width / 2;
+    bit_rowinc = bitmap->pitch - bitmap_width;
+    u_plane_size = (video_width / 2)*(video_height / 2);
+
+    y1 = y0 + bitmap_y0;
+    x1 = x0 + bitmap_x0;
+    p = pixbuf + video_width*y1 + x1;
+    bitp = bitmap->buffer + bitmap->pitch*bitmap_y0 + bitmap_x0;
+    for (y = bitmap_y0; y < bitmap_height; y++){
+      int n;
+      for(n=bitmap_width; n>0; --n){
+	v = *bitp;
+	if (v) {
+	  p[-1] = 0;
+	  p[ 1] = 0;
+	  p[-video_width] = 0;
+	  p[ video_width] = 0;
+	}
+	p++;
+	bitp++;
+      }
+      p += rowinc;
+      bitp += bit_rowinc;
+    }
+
+    y = bitmap_y0;
+    y1 = y0 + bitmap_y0;
+    x1 = x0 + bitmap_x0;
+    bitp = bitmap->buffer + bitmap->pitch*bitmap_y0 + bitmap_x0;
+    p = pixbuf + video_width*y1 + x1;
+    u_p = pixbuf + video_width*video_height + (video_width >> 1)*(y1 >> 1) + (x1 >> 1);
+    skip_y = 0;
+    skip_x = 0;
+
+    for ( ; y < bitmap_height; y++){
+      int n;
+      x1 = x0 + bitmap_x0;
+      skip_x = 0;
+      for(n = bitmap_width; n>0; --n){
+	v = *bitp;
+	if (v) {
+	  *p = v;
+	  if (!skip_y) {
+	    u_p[0] = u_p[u_plane_size] = 0x80;
+	  }
+	}
+	if (!skip_y) {
+	  skip_x = !skip_x;
+	  if (!skip_x) u_p++;
+	}
+	p++;
+	bitp++;
+      }
+      /*if (!skip_x && !skip_y) u_p--; */
+      p += rowinc;
+      bitp += bit_rowinc;
+      skip_y = !skip_y;
+      u_p += skip_y? uv_rowinc : 0;
+    }
+}
+
+
+static void
+gst_textoverlay_video_chain(GstPad *pad, GstBuffer *buf)
+{
+    GstTextOverlay *overlay;
+    guchar         *pixbuf;
+    gint            x0, y0;
+
+    g_return_if_fail(pad != NULL);
+    g_return_if_fail(GST_IS_PAD(pad));
+    g_return_if_fail(buf != NULL);
+    overlay = GST_TEXTOVERLAY(gst_pad_get_parent(pad));
+    g_return_if_fail(overlay != NULL);
+    g_return_if_fail(GST_IS_TEXTOVERLAY(overlay));
+
+    pixbuf = GST_BUFFER_DATA(buf);
+
+    x0 = overlay->x0;
+    y0 = overlay->y0;
+    switch (overlay->valign)
+    {
+    case GST_TEXT_OVERLAY_VALIGN_BOTTOM:
+	y0 += overlay->bitmap.rows;
+	break;
+    case GST_TEXT_OVERLAY_VALIGN_BASELINE:
+	y0 -= (overlay->bitmap.rows - overlay->baseline_y);
+	break;
+    case GST_TEXT_OVERLAY_VALIGN_TOP:
+	break;
+    }
+
+    switch (overlay->halign)
+    {
+    case GST_TEXT_OVERLAY_HALIGN_LEFT:
+	break;
+    case GST_TEXT_OVERLAY_HALIGN_RIGHT:
+	x0 -= overlay->bitmap.width;
+	break;
+    case GST_TEXT_OVERLAY_HALIGN_CENTER:
+	x0 -= overlay->bitmap.width / 2;
+	break;
+    }
+
+    if (overlay->bitmap.buffer)
+	gst_text_overlay_blit_yuv420(overlay, &overlay->bitmap, pixbuf, x0, y0);
+
+    gst_pad_push(overlay->srcpad, buf);
+}
+
+
+static void
+gst_textoverlay_loop(GstElement *element)
+{
+    GstTextOverlay *overlay;
+    GstBuffer      *video_frame;
+    GstBuffer      *new_text;
+    guint64         now;
+
+    g_return_if_fail(element != NULL);
+    g_return_if_fail(GST_IS_TEXTOVERLAY(element));
+    overlay = GST_TEXTOVERLAY(element);
+
+    video_frame = gst_pad_pull(overlay->video_sinkpad);
+    now = GST_BUFFER_TIMESTAMP(video_frame);
+    if (now >= overlay->next_known_text_change) {
+      GST_DEBUG ( "rendering '%s'", overlay->next_known_text->str);
+      pango_layout_set_markup(overlay->layout,
+			      overlay->next_known_text->str,
+			      overlay->next_known_text->len);
+      render_text(overlay);
+      overlay->next_known_text_change = 0;
+    }
+    if (overlay->next_known_text_change == 0) {
+	/* read all text buffers until we get one "in the future" */
+	while (1) {
+	    new_text = gst_pad_pull(overlay->text_sinkpad);
+	    if (!new_text)
+		break;
+	    overlay->next_known_text_change =
+		GST_BUFFER_TIMESTAMP(new_text);
+	    overlay->next_known_text = g_string_truncate
+		(overlay->next_known_text, 0);
+	    overlay->next_known_text = g_string_append_len
+		(overlay->next_known_text,
+		 (gchar *) GST_BUFFER_DATA(new_text),
+		 GST_BUFFER_SIZE(new_text));
+	    gst_buffer_unref(new_text);
+            break;
+	}
+    }
+    gst_textoverlay_video_chain(overlay->srcpad, video_frame);
+}
+
+
+static GstElementStateReturn
+gst_textoverlay_change_state(GstElement *element)
+{
+    GstTextOverlay *overlay;
+
+    overlay = GST_TEXTOVERLAY(element);
+
+    switch (GST_STATE_TRANSITION(element))
+    {
+    case GST_STATE_PAUSED_TO_PLAYING:
+	break;
+    case GST_STATE_PLAYING_TO_PAUSED:
+	break;
+    case GST_STATE_PAUSED_TO_READY:
+	break;
+    }
+
+    parent_class->change_state(element);
+
+    return GST_STATE_SUCCESS;
+}
+
+static void
+gst_textoverlay_finalize(GObject *object)
+{
+    GstTextOverlay *overlay = GST_TEXTOVERLAY(object);
+
+    if (overlay->layout) {
+	g_object_unref(overlay->layout);
+	overlay->layout = NULL;
+    }
+    if (overlay->bitmap.buffer) {
+	g_free(overlay->bitmap.buffer);
+	overlay->bitmap.buffer = NULL;
+    }
+
+    G_OBJECT_CLASS(parent_class)->finalize(object);
+}
+
+static void
+gst_textoverlay_init(GstTextOverlay *overlay)
+{
+    /* video sink */
+    overlay->video_sinkpad = gst_pad_new_from_template(
+	GST_PAD_TEMPLATE_GET(video_sink_template_factory), "video_sink");
+/*     gst_pad_set_chain_function(overlay->video_sinkpad, gst_textoverlay_video_chain); */
+    gst_pad_set_link_function(overlay->video_sinkpad, gst_textoverlay_video_sinkconnect);
+    gst_element_add_pad(GST_ELEMENT(overlay), overlay->video_sinkpad);
+
+    /* text sink */
+    overlay->text_sinkpad = gst_pad_new_from_template(
+	GST_PAD_TEMPLATE_GET(text_sink_template_factory), "text_sink");
+/*     gst_pad_set_link_function(overlay->text_sinkpad, gst_textoverlay_text_sinkconnect); */
+    gst_element_add_pad(GST_ELEMENT(overlay), overlay->text_sinkpad);
+
+    /* (video) source */
+    overlay->srcpad = gst_pad_new_from_template(
+	GST_PAD_TEMPLATE_GET(textoverlay_src_template_factory), "src");
+    gst_element_add_pad(GST_ELEMENT(overlay), overlay->srcpad);
+
+    overlay->layout = pango_layout_new(GST_TEXTOVERLAY_GET_CLASS(overlay)->pango_context);
+    memset(&overlay->bitmap, 0, sizeof(overlay->bitmap));
+
+    overlay->halign = GST_TEXT_OVERLAY_HALIGN_CENTER;
+    overlay->valign = GST_TEXT_OVERLAY_VALIGN_BASELINE;
+    overlay->x0 = overlay->y0 = 0;
+
+    overlay->next_known_text = g_string_new(NULL);
+    overlay->next_known_text_change = 0;
+
+    gst_element_set_loop_function(GST_ELEMENT(overlay), gst_textoverlay_loop);
+}
+
+
+static void
+gst_textoverlay_set_property(GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
+{
+    GstTextOverlay *overlay;
+
+    /* it's not null if we got it, but it might not be ours */
+    g_return_if_fail(GST_IS_TEXTOVERLAY(object));
+    overlay = GST_TEXTOVERLAY(object);
+
+    switch (prop_id)
+    {
+
+    case ARG_TEXT:
+	pango_layout_set_markup(overlay->layout, g_value_get_string(value), -1);
+	render_text(overlay);
+	break;
+
+    case ARG_VALIGN:
+	if (strcasecmp(g_value_get_string(value), "baseline") == 0)
+	    overlay->valign = GST_TEXT_OVERLAY_VALIGN_BASELINE;
+	else if (strcasecmp(g_value_get_string(value), "bottom") == 0)
+	    overlay->valign = GST_TEXT_OVERLAY_VALIGN_BOTTOM;
+	else if (strcasecmp(g_value_get_string(value), "top") == 0)
+	    overlay->valign = GST_TEXT_OVERLAY_VALIGN_TOP;
+	else
+	    g_warning("Invalid 'valign' property value: %s", 
+		      g_value_get_string(value));
+	break;
+
+    case ARG_HALIGN:
+	if (strcasecmp(g_value_get_string(value), "left") == 0)
+	    overlay->halign = GST_TEXT_OVERLAY_HALIGN_LEFT;
+	else if (strcasecmp(g_value_get_string(value), "right") == 0)
+	    overlay->halign = GST_TEXT_OVERLAY_HALIGN_RIGHT;
+	else if (strcasecmp(g_value_get_string(value), "center") == 0)
+	    overlay->halign = GST_TEXT_OVERLAY_HALIGN_CENTER;
+	else
+	    g_warning("Invalid 'halign' property value: %s", 
+		      g_value_get_string(value));
+	break;
+
+    case ARG_X0:
+	overlay->x0 = g_value_get_int(value);
+	break;
+
+    case ARG_Y0:
+	overlay->y0 = g_value_get_int(value);
+	break;
+
+    case ARG_FONT_DESC:
+    {
+	PangoFontDescription *desc;
+	desc = pango_font_description_from_string(g_value_get_string(value));
+	if (desc) {
+	    g_message("font description set: %s", g_value_get_string(value));
+	    pango_layout_set_font_description(overlay->layout, desc);
+	    pango_font_description_free(desc);
+	    render_text(overlay);
+	} else
+	    g_warning("font description parse failed: %s", g_value_get_string(value));
+	break;
+    }
+
+    default:
+	break;
+    }
+}
+
+static void
+gst_textoverlay_get_property(GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
+{
+    GstTextOverlay *overlay;
+
+    /* it's not null if we got it, but it might not be ours */
+    g_return_if_fail(GST_IS_TEXTOVERLAY(object));
+    overlay = GST_TEXTOVERLAY(object);
+
+    switch (prop_id) {
+    default:
+	G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
+	break;
+    }
+}
+
+static gboolean
+plugin_init(GModule *module, GstPlugin *plugin)
+{
+    GstElementFactory *factory;
+
+    factory = gst_element_factory_new("textoverlay", GST_TYPE_TEXTOVERLAY,
+				      &textoverlay_details);
+    g_return_val_if_fail(factory != NULL, FALSE);
+    gst_element_factory_set_rank(factory, GST_ELEMENT_RANK_PRIMARY);
+
+    gst_element_factory_add_pad_template(factory, 
+					 GST_PAD_TEMPLATE_GET(textoverlay_src_template_factory));
+    gst_element_factory_add_pad_template(factory, 
+					 GST_PAD_TEMPLATE_GET(video_sink_template_factory));
+    gst_element_factory_add_pad_template(factory, 
+					 GST_PAD_TEMPLATE_GET(text_sink_template_factory));
+
+    gst_plugin_add_feature(plugin, GST_PLUGIN_FEATURE(factory));
+
+    //texttestsrc_plugin_init(module, plugin);
+    //subparse_plugin_init(module, plugin);
+    return TRUE;
+}
+
+GstPluginDesc plugin_desc = {
+    GST_VERSION_MAJOR,
+    GST_VERSION_MINOR,
+    "textoverlay",
+    plugin_init
+};
+
diff --git a/ext/pango/gsttextoverlay.h b/ext/pango/gsttextoverlay.h
new file mode 100644
index 00000000..ea8f5bf7
--- /dev/null
+++ b/ext/pango/gsttextoverlay.h
@@ -0,0 +1,71 @@
+/* -*- Mode: C; c-file-style: "stroustrup" -*- */
+#ifndef __GST_TEXTOVERLAY_H__
+#define __GST_TEXTOVERLAY_H__
+
+#include <gst/gst.h>
+#include <pango/pangoft2.h>
+
+G_BEGIN_DECLS
+
+#define GST_TYPE_TEXTOVERLAY           (gst_textoverlay_get_type())
+#define GST_TEXTOVERLAY(obj)           (G_TYPE_CHECK_INSTANCE_CAST((obj),\
+                                        GST_TYPE_TEXTOVERLAY, GstTextOverlay))
+#define GST_TEXTOVERLAY_CLASS(klass)   (G_TYPE_CHECK_CLASS_CAST((klass),\
+                                        GST_TYPE_ULAW, GstTextOverlay))
+#define GST_TEXTOVERLAY_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj),\
+                                        GST_TYPE_TEXTOVERLAY, GstTextOverlayClass))
+#define GST_IS_TEXTOVERLAY(obj)        (G_TYPE_CHECK_INSTANCE_TYPE((obj),\
+                                        GST_TYPE_TEXTOVERLAY))
+#define GST_IS_TEXTOVERLAY_CLASS(obj)  (G_TYPE_CHECK_CLASS_TYPE((klass),\
+                                        GST_TYPE_TEXTOVERLAY))
+
+typedef struct _GstTextOverlay      GstTextOverlay;
+typedef struct _GstTextOverlayClass GstTextOverlayClass;
+
+typedef enum _GstTextOverlayVAlign GstTextOverlayVAlign;
+typedef enum _GstTextOverlayHAlign GstTextOverlayHAlign;
+
+enum _GstTextOverlayVAlign {
+    GST_TEXT_OVERLAY_VALIGN_BASELINE,
+    GST_TEXT_OVERLAY_VALIGN_BOTTOM,
+    GST_TEXT_OVERLAY_VALIGN_TOP,
+};
+
+enum _GstTextOverlayHAlign {
+    GST_TEXT_OVERLAY_HALIGN_LEFT,
+    GST_TEXT_OVERLAY_HALIGN_CENTER,
+    GST_TEXT_OVERLAY_HALIGN_RIGHT,
+};
+
+
+struct _GstTextOverlay {
+    GstElement            element;
+
+    GstPad               *video_sinkpad;
+    GstPad               *text_sinkpad;
+    GstPad               *srcpad;
+    gint                  width;
+    gint                  height;
+    PangoLayout          *layout;
+    FT_Bitmap             bitmap;
+    gint                  bitmap_buffer_size;
+    gint                  baseline_y;
+    GstTextOverlayVAlign  valign;
+    GstTextOverlayHAlign  halign;
+    gint                  x0;
+    gint                  y0;
+    guint64               next_known_text_change;
+    GString              *next_known_text;
+};
+
+struct _GstTextOverlayClass {
+    GstElementClass parent_class;
+
+    PangoContext *pango_context;
+};
+
+GType gst_textoverlay_get_type(void) G_GNUC_CONST;
+
+G_END_DECLS
+
+#endif /* __GST_TEXTOVERLAY_H */