1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
|
/* GStreamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
* Copyright (C) <2003> David Schleef <ds@schleef.org>
* Copyright (C) <2006> Julien Moutte <julien@moutte.net>
* Copyright (C) <2006> Zeeshan Ali <zeeshan.ali@nokia.com>
* Copyright (C) <2006-2008> Tim-Philipp Müller <tim centricular net>
* Copyright (C) <2009> Young-Ho Cha <ganadist@gmail.com>
* Copyright (C) <2011> Sebastian Dröge <sebastian.droege@collabora.co.uk>
*
* 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-textoverlay
* @see_also: #GstTextRender, #GstTextOverlay, #GstTimeOverlay, #GstSubParse
*
* This plugin renders text on top of a video stream. This can be either
* static text or text from buffers received on the text sink pad, e.g.
* as produced by the subparse element. If the text sink pad is not linked,
* the text set via the "text" property will be rendered. If the text sink
* pad is linked, text will be rendered as it is received on that pad,
* honouring and matching the buffer timestamps of both input streams.
*
* The text can contain newline characters and text wrapping is enabled by
* default.
*
* <refsect2>
* <title>Example launch lines</title>
* |[
* gst-launch -v videotestsrc ! textoverlay text="Room A" valign=top halign=left ! xvimagesink
* ]| Here is a simple pipeline that displays a static text in the top left
* corner of the video picture
* |[
* gst-launch -v filesrc location=subtitles.srt ! subparse ! txt. videotestsrc ! timeoverlay ! textoverlay name=txt shaded-background=yes ! xvimagesink
* ]| Here is another pipeline that displays subtitles from an .srt subtitle
* file, centered at the bottom of the picture and with a rectangular shading
* around the text in the background:
* <para>
* If you do not have such a subtitle file, create one looking like this
* in a text editor:
* |[
* 1
* 00:00:03,000 --> 00:00:05,000
* Hello? (3-5s)
*
* 2
* 00:00:08,000 --> 00:00:13,000
* Yes, this is a subtitle. Don't
* you like it? (8-13s)
*
* 3
* 00:00:18,826 --> 00:01:02,886
* Uh? What are you talking about?
* I don't understand (18-62s)
* ]|
* One can also feed arbitrary live text into the element:
* |[
* gst-launch fdsrc fd=0 ! text/x-raw,format=utf8 ! txt. videotestsrc ! \
* textoverlay name=txt shaded-background=yes font-desc="Serif 40" wait-text=false ! \
* xvimagesink
* ]| This shows new text as entered on the terminal (stdin). This is not suited
* for subtitles as the test overlay is not timed. Subtitles should use
* timestamped formats. For the above use case one can also read the text from
* the application as set the #GstTextOverlay:text property.
* </para>
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gsttextoverlay.h>
static GstStaticPadTemplate text_sink_template_factory =
GST_STATIC_PAD_TEMPLATE ("text_sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("text/x-raw, format = { pango-markup, utf8 }")
);
G_DEFINE_TYPE (GstTextOverlay, gst_text_overlay, GST_TYPE_BASE_TEXT_OVERLAY);
static void
gst_text_overlay_class_init (GstTextOverlayClass * klass)
{
GstElementClass *element_class = (GstElementClass *) klass;
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&text_sink_template_factory));
gst_element_class_set_static_metadata (element_class, "Text overlay",
"Filter/Editor/Video",
"Adds text strings on top of a video buffer",
"David Schleef <ds@schleef.org>, " "Zeeshan Ali <zeeshan.ali@nokia.com>");
}
static void
gst_text_overlay_init (GstTextOverlay * overlay)
{
}
|
