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/* GStreamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
* Copyright (C) <2005> Tim-Philipp Müller <tim@centricular.net>
*
* 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:element-timeoverlay
* @see_also: #GstTextOverlay, #GstClockOverlay
*
* This element overlays the buffer time stamps of a video stream on
* top of itself. You can position the text and configure the font details
* using the properties of the #GstTextOverlay class. By default, the
* time stamp is displayed in the top left corner of the picture, with some
* padding to the left and to the top.
*
* <refsect2>
* |[
* gst-launch -v videotestsrc ! timeoverlay ! xvimagesink
* ]| Display the time stamps in the top left
* corner of the video picture.
* |[
* gst-launch -v videotestsrc ! timeoverlay halign=right valign=bottom text="Stream time:" shaded-background=true ! xvimagesink
* ]| Another pipeline that displays the time stamps with some leading
* text in the bottom right corner of the video picture, with the background
* of the text being shaded in order to make it more legible on top of a
* bright video background.
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/video/video.h>
#include <gsttimeoverlay.h>
GST_BOILERPLATE (GstTimeOverlay, gst_time_overlay, GstTextOverlay,
GST_TYPE_TEXT_OVERLAY);
static void
gst_time_overlay_base_init (gpointer g_class)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
gst_element_class_set_details_simple (element_class, "Time overlay",
"Filter/Editor/Video",
"Overlays buffer time stamps on a video stream",
"Tim-Philipp Müller <tim@centricular.net>");
}
static gchar *
gst_time_overlay_render_time (GstTimeOverlay * overlay, GstClockTime time)
{
guint hours, mins, secs, msecs;
if (!GST_CLOCK_TIME_IS_VALID (time))
return g_strdup ("");
hours = (guint) (time / (GST_SECOND * 60 * 60));
mins = (guint) ((time / (GST_SECOND * 60)) % 60);
secs = (guint) ((time / GST_SECOND) % 60);
msecs = (guint) ((time % GST_SECOND) / (1000 * 1000));
return g_strdup_printf ("%u:%02u:%02u.%03u", hours, mins, secs, msecs);
}
/* Called with lock held */
static gchar *
gst_time_overlay_get_text (GstTextOverlay * overlay, GstBuffer * video_frame)
{
GstClockTime time = GST_BUFFER_TIMESTAMP (video_frame);
gchar *time_str, *txt, *ret;
overlay->need_render = TRUE;
if (!GST_CLOCK_TIME_IS_VALID (time)) {
GST_DEBUG ("buffer without valid timestamp");
return g_strdup ("");
}
GST_DEBUG ("buffer with timestamp %" GST_TIME_FORMAT, GST_TIME_ARGS (time));
txt = g_strdup (overlay->default_text);
time_str = gst_time_overlay_render_time (GST_TIME_OVERLAY (overlay), time);
if (txt != NULL && *txt != '\0') {
ret = g_strdup_printf ("%s %s", txt, time_str);
} else {
ret = time_str;
time_str = NULL;
}
g_free (txt);
g_free (time_str);
return ret;
}
static void
gst_time_overlay_class_init (GstTimeOverlayClass * klass)
{
GstTextOverlayClass *gsttextoverlay_class;
gsttextoverlay_class = (GstTextOverlayClass *) klass;
gsttextoverlay_class->get_text = gst_time_overlay_get_text;
}
static void
gst_time_overlay_init (GstTimeOverlay * overlay, GstTimeOverlayClass * klass)
{
PangoFontDescription *font_description;
GstTextOverlay *textoverlay;
PangoContext *context;
textoverlay = GST_TEXT_OVERLAY (overlay);
context = GST_TEXT_OVERLAY_CLASS (klass)->pango_context;
pango_context_set_language (context, pango_language_from_string ("en_US"));
pango_context_set_base_dir (context, PANGO_DIRECTION_LTR);
font_description = pango_font_description_new ();
pango_font_description_set_family_static (font_description, "Monospace");
pango_font_description_set_style (font_description, PANGO_STYLE_NORMAL);
pango_font_description_set_variant (font_description, PANGO_VARIANT_NORMAL);
pango_font_description_set_weight (font_description, PANGO_WEIGHT_NORMAL);
pango_font_description_set_stretch (font_description, PANGO_STRETCH_NORMAL);
pango_font_description_set_size (font_description, 18 * PANGO_SCALE);
pango_context_set_font_description (context, font_description);
pango_font_description_free (font_description);
textoverlay->valign = GST_TEXT_OVERLAY_VALIGN_TOP;
textoverlay->halign = GST_TEXT_OVERLAY_HALIGN_LEFT;
}
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