• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /* GStreamer
2  * Copyright (C) 1999 Erik Walthinsen <omega@cse.ogi.edu>
3  * Copyright (C) 2005-2014 Tim-Philipp Müller <tim@centricular.net>
4  *
5  * This library is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Library General Public
7  * License as published by the Free Software Foundation; either
8  * version 2 of the License, or (at your option) any later version.
9  *
10  * This library is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * Library General Public License for more details.
14  *
15  * You should have received a copy of the GNU Library General Public
16  * License along with this library; if not, write to the
17  * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
18  * Boston, MA 02110-1301, USA.
19  */
20 
21 /**
22  * SECTION:element-timeoverlay
23  * @title: timeoverlay
24  * @see_also: #GstBaseTextOverlay, #GstClockOverlay
25  *
26  * This element overlays the buffer time stamps of a video stream on
27  * top of itself. You can position the text and configure the font details
28  * using the properties of the #GstBaseTextOverlay class. By default, the
29  * time stamp is displayed in the top left corner of the picture, with some
30  * padding to the left and to the top.
31  *
32  * |[
33  * gst-launch-1.0 -v videotestsrc ! timeoverlay ! autovideosink
34  * ]|
35  * Display the time stamps in the top left corner of the video picture.
36  * |[
37  * gst-launch-1.0 -v videotestsrc ! timeoverlay halignment=right valignment=bottom text="Stream time:" shaded-background=true font-desc="Sans, 24" ! autovideosink
38  * ]|
39  * Another pipeline that displays the time stamps with some leading
40  * text in the bottom right corner of the video picture, with the background
41  * of the text being shaded in order to make it more legible on top of a
42  * bright video background.
43  *
44  */
45 
46 #ifdef HAVE_CONFIG_H
47 #include "config.h"
48 #endif
49 
50 #include <gst/video/video.h>
51 
52 #include "gsttimeoverlay.h"
53 
54 #define DEFAULT_TIME_LINE GST_TIME_OVERLAY_TIME_LINE_BUFFER_TIME
55 
56 enum
57 {
58   PROP_0,
59   PROP_TIME_LINE
60 };
61 
62 #define gst_time_overlay_parent_class parent_class
63 G_DEFINE_TYPE (GstTimeOverlay, gst_time_overlay, GST_TYPE_BASE_TEXT_OVERLAY);
64 
65 static void gst_time_overlay_set_property (GObject * object, guint prop_id,
66     const GValue * value, GParamSpec * pspec);
67 static void gst_time_overlay_get_property (GObject * object, guint prop_id,
68     GValue * value, GParamSpec * pspec);
69 
70 #define GST_TYPE_TIME_OVERLAY_TIME_LINE (gst_time_overlay_time_line_type())
71 static GType
gst_time_overlay_time_line_type(void)72 gst_time_overlay_time_line_type (void)
73 {
74   static GType time_line_type = 0;
75   static const GEnumValue modes[] = {
76     {GST_TIME_OVERLAY_TIME_LINE_BUFFER_TIME, "buffer-time", "buffer-time"},
77     {GST_TIME_OVERLAY_TIME_LINE_STREAM_TIME, "stream-time", "stream-time"},
78     {GST_TIME_OVERLAY_TIME_LINE_RUNNING_TIME, "running-time", "running-time"},
79     {GST_TIME_OVERLAY_TIME_LINE_TIME_CODE, "time-code", "time-code"},
80     {0, NULL, NULL},
81   };
82 
83   if (!time_line_type) {
84     time_line_type = g_enum_register_static ("GstTimeOverlayTimeLine", modes);
85   }
86   return time_line_type;
87 }
88 
89 static gchar *
gst_time_overlay_render_time(GstTimeOverlay * overlay,GstClockTime time)90 gst_time_overlay_render_time (GstTimeOverlay * overlay, GstClockTime time)
91 {
92   guint hours, mins, secs, msecs;
93 
94   if (!GST_CLOCK_TIME_IS_VALID (time))
95     return g_strdup ("");
96 
97   hours = (guint) (time / (GST_SECOND * 60 * 60));
98   mins = (guint) ((time / (GST_SECOND * 60)) % 60);
99   secs = (guint) ((time / GST_SECOND) % 60);
100   msecs = (guint) ((time % GST_SECOND) / (1000 * 1000));
101 
102   return g_strdup_printf ("%u:%02u:%02u.%03u", hours, mins, secs, msecs);
103 }
104 
105 /* Called with lock held */
106 static gchar *
gst_time_overlay_get_text(GstBaseTextOverlay * overlay,GstBuffer * video_frame)107 gst_time_overlay_get_text (GstBaseTextOverlay * overlay,
108     GstBuffer * video_frame)
109 {
110   GstTimeOverlayTimeLine time_line;
111   gchar *time_str, *txt, *ret;
112 
113   overlay->need_render = TRUE;
114 
115   time_line = g_atomic_int_get (&GST_TIME_OVERLAY_CAST (overlay)->time_line);
116   if (time_line == GST_TIME_OVERLAY_TIME_LINE_TIME_CODE) {
117     GstVideoTimeCodeMeta *tc_meta =
118         gst_buffer_get_video_time_code_meta (video_frame);
119     if (!tc_meta) {
120       GST_DEBUG ("buffer without valid timecode");
121       return g_strdup ("00:00:00:00");
122     }
123     time_str = gst_video_time_code_to_string (&tc_meta->tc);
124     GST_DEBUG ("buffer with timecode %s", time_str);
125   } else {
126     GstClockTime ts, ts_buffer;
127     GstSegment *segment = &overlay->segment;
128 
129     ts_buffer = GST_BUFFER_TIMESTAMP (video_frame);
130 
131     if (!GST_CLOCK_TIME_IS_VALID (ts_buffer)) {
132       GST_DEBUG ("buffer without valid timestamp");
133       return g_strdup ("");
134     }
135 
136     GST_DEBUG ("buffer with timestamp %" GST_TIME_FORMAT,
137         GST_TIME_ARGS (ts_buffer));
138 
139     switch (time_line) {
140       case GST_TIME_OVERLAY_TIME_LINE_STREAM_TIME:
141         ts = gst_segment_to_stream_time (segment, GST_FORMAT_TIME, ts_buffer);
142         break;
143       case GST_TIME_OVERLAY_TIME_LINE_RUNNING_TIME:
144         ts = gst_segment_to_running_time (segment, GST_FORMAT_TIME, ts_buffer);
145         break;
146       case GST_TIME_OVERLAY_TIME_LINE_BUFFER_TIME:
147       default:
148         ts = ts_buffer;
149         break;
150     }
151 
152     time_str = gst_time_overlay_render_time (GST_TIME_OVERLAY (overlay), ts);
153   }
154   txt = g_strdup (overlay->default_text);
155 
156   if (txt != NULL && *txt != '\0') {
157     ret = g_strdup_printf ("%s %s", txt, time_str);
158   } else {
159     ret = time_str;
160     time_str = NULL;
161   }
162 
163   g_free (txt);
164   g_free (time_str);
165 
166   return ret;
167 }
168 
169 static void
gst_time_overlay_class_init(GstTimeOverlayClass * klass)170 gst_time_overlay_class_init (GstTimeOverlayClass * klass)
171 {
172   GstElementClass *gstelement_class;
173   GstBaseTextOverlayClass *gsttextoverlay_class;
174   GObjectClass *gobject_class;
175 
176   gsttextoverlay_class = (GstBaseTextOverlayClass *) klass;
177   gstelement_class = (GstElementClass *) klass;
178   gobject_class = (GObjectClass *) klass;
179 
180   gst_element_class_set_static_metadata (gstelement_class, "Time overlay",
181       "Filter/Editor/Video",
182       "Overlays buffer time stamps on a video stream",
183       "Tim-Philipp Müller <tim@centricular.net>");
184 
185   gsttextoverlay_class->get_text = gst_time_overlay_get_text;
186 
187   gobject_class->set_property = gst_time_overlay_set_property;
188   gobject_class->get_property = gst_time_overlay_get_property;
189 
190   g_object_class_install_property (gobject_class, PROP_TIME_LINE,
191       g_param_spec_enum ("time-mode", "Time Mode", "What time to show",
192           GST_TYPE_TIME_OVERLAY_TIME_LINE, DEFAULT_TIME_LINE,
193           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
194 }
195 
196 static void
gst_time_overlay_init(GstTimeOverlay * overlay)197 gst_time_overlay_init (GstTimeOverlay * overlay)
198 {
199   GstBaseTextOverlay *textoverlay;
200   PangoContext *context;
201   PangoFontDescription *font_description;
202 
203   textoverlay = GST_BASE_TEXT_OVERLAY (overlay);
204 
205   textoverlay->valign = GST_BASE_TEXT_OVERLAY_VALIGN_TOP;
206   textoverlay->halign = GST_BASE_TEXT_OVERLAY_HALIGN_LEFT;
207 
208   overlay->time_line = DEFAULT_TIME_LINE;
209 
210   context = textoverlay->pango_context;
211 
212   pango_context_set_language (context, pango_language_from_string ("en_US"));
213   pango_context_set_base_dir (context, PANGO_DIRECTION_LTR);
214 
215   font_description = pango_font_description_new ();
216   pango_font_description_set_family_static (font_description, "Monospace");
217   pango_font_description_set_style (font_description, PANGO_STYLE_NORMAL);
218   pango_font_description_set_variant (font_description, PANGO_VARIANT_NORMAL);
219   pango_font_description_set_weight (font_description, PANGO_WEIGHT_NORMAL);
220   pango_font_description_set_stretch (font_description, PANGO_STRETCH_NORMAL);
221   pango_font_description_set_size (font_description, 18 * PANGO_SCALE);
222   pango_context_set_font_description (context, font_description);
223   pango_font_description_free (font_description);
224 }
225 
226 static void
gst_time_overlay_set_property(GObject * object,guint prop_id,const GValue * value,GParamSpec * pspec)227 gst_time_overlay_set_property (GObject * object, guint prop_id,
228     const GValue * value, GParamSpec * pspec)
229 {
230   GstTimeOverlay *overlay = GST_TIME_OVERLAY (object);
231 
232   switch (prop_id) {
233     case PROP_TIME_LINE:
234       g_atomic_int_set (&overlay->time_line, g_value_get_enum (value));
235       break;
236     default:
237       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
238       break;
239   }
240 }
241 
242 static void
gst_time_overlay_get_property(GObject * object,guint prop_id,GValue * value,GParamSpec * pspec)243 gst_time_overlay_get_property (GObject * object, guint prop_id,
244     GValue * value, GParamSpec * pspec)
245 {
246   GstTimeOverlay *overlay = GST_TIME_OVERLAY (object);
247 
248   switch (prop_id) {
249     case PROP_TIME_LINE:
250       g_value_set_enum (value, g_atomic_int_get (&overlay->time_line));
251       break;
252     default:
253       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
254       break;
255   }
256 }
257