diff -r 000000000000 -r 0e761a78d257 gst_plugins_base/ext/pango/gsttimeoverlay.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/gst_plugins_base/ext/pango/gsttimeoverlay.c Thu Dec 17 08:53:32 2009 +0200 @@ -0,0 +1,160 @@ +/* GStreamer + * Copyright (C) <1999> Erik Walthinsen + * Copyright (C) <2005> Tim-Philipp Müller + * + * 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. + * + * + * Here is a simple pipeline that displays the time stamps in the top left + * corner of the video picture: + * + * gst-launch -v videotestsrc ! timeoverlay ! xvimagesink + * + * + * + * Here is 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: + * + * gst-launch -v videotestsrc ! timeoverlay halign=right valign=bottom text="Stream time:" shaded-background=true ! xvimagesink + * + * + * + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include + +#include + +static const GstElementDetails time_overlay_details = +GST_ELEMENT_DETAILS ("Time overlay", + "Filter/Editor/Video", + "Overlays buffer time stamps on a video stream", + "Tim-Philipp Müller "); + +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 (element_class, &time_overlay_details); +} + +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; +}