1 /* GStreamer interactive textoverlay test

     2  * Copyright (C) 2007 Tim-Philipp Müller <tim centricular net>

     3  *

     4  * This library is free software; you can redistribute it and/or

     5  * modify it under the terms of the GNU Library General Public

     6  * License as published by the Free Software Foundation; either

     7  * version 2 of the License, or (at your option) any later version.

     8  *

     9  * This library is distributed in the hope that it will be useful,

    10  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

    12  * Library General Public License for more details.

    13  *

    14  * You should have received a copy of the GNU Library General Public

    15  * License along with this library; if not, write to the

    16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,

    17  * Boston, MA 02111-1307, USA.

    18  */

    19 

    20 #ifdef HAVE_CONFIG_H

    21 #include "config.h"

    22 #endif

    23 

    24 #include <gst/gst.h>

    25 

    26 static void

    27 set_enum_property_by_name (gpointer object, const gchar * prop,

    28     const gchar * value)

    29 {

    30   GParamSpec *pspec;

    31   GValue val = { 0, };

    32   GEnumClass *eclass;

    33   GEnumValue *eval;

    34 

    35   pspec = g_object_class_find_property (G_OBJECT_GET_CLASS (object), prop);

    36   g_return_if_fail (pspec != NULL);

    37 

    38   g_value_init (&val, pspec->value_type);

    39   g_object_get_property (G_OBJECT (object), prop, &val);

    40   eclass = G_ENUM_CLASS (g_type_class_peek (G_VALUE_TYPE (&val)));

    41   g_return_if_fail (eclass != NULL);

    42   eval = g_enum_get_value_by_name (eclass, value);

    43   if (eval == NULL)

    44     eval = g_enum_get_value_by_nick (eclass, value);

    45   g_return_if_fail (eval != NULL);

    46   g_value_set_enum (&val, eval->value);

    47   g_object_set_property (G_OBJECT (object), prop, &val);

    48   g_value_unset (&val);

    49 }

    50 

    51 static void

    52 show_text (GstElement * textoverlay, const gchar * txt, const gchar * valign,

    53     const gchar * halign, const gchar * line_align)

    54 {

    55   GstElement *pipe;

    56 

    57   g_object_set (textoverlay, "text", txt, NULL);

    58 

    59   set_enum_property_by_name (textoverlay, "valignment", valign);

    60   set_enum_property_by_name (textoverlay, "halignment", halign);

    61   set_enum_property_by_name (textoverlay, "line-alignment", line_align);

    62 

    63   pipe = textoverlay;

    64   while (GST_ELEMENT_PARENT (pipe))

    65     pipe = GST_ELEMENT_PARENT (pipe);

    66 

    67   gst_element_set_state (pipe, GST_STATE_PLAYING);

    68   gst_bus_poll (GST_ELEMENT_BUS (pipe), GST_MESSAGE_ERROR, 2 * GST_SECOND);

    69   gst_element_set_state (pipe, GST_STATE_NULL);

    70 }

    71 

    72 int

    73 main (int argc, char **argv)

    74 {

    75   GstElement *pipe, *toverlay;

    76   const gchar *valigns[] = { /* "baseline", */ "bottom", "top" };

    77   const gchar *haligns[] = { "left", "center", "right" };

    78   const gchar *linealigns[] = { "left", "center", "right" };

    79   gint a, b, c;

    80 

    81   gst_init (&argc, &argv);

    82 

    83   pipe = gst_parse_launch ("videotestsrc pattern=black ! textoverlay name=t ! "

    84       " ffmpegcolorspace ! videoscale ! autovideosink", NULL);

    85   g_assert (pipe);

    86 

    87   toverlay = gst_bin_get_by_name (GST_BIN (pipe), "t");

    88   g_assert (toverlay);

    89 

    90   g_object_set (toverlay, "xpad", 3, "ypad", 3, NULL);

    91 

    92   for (a = 0; a < G_N_ELEMENTS (valigns); ++a) {

    93     for (b = 0; b < G_N_ELEMENTS (haligns); ++b) {

    94       for (c = 0; c < G_N_ELEMENTS (linealigns); ++c) {

    95         gchar *s;

    96 

    97         s = g_strdup_printf ("line-alignment = %s\n"

    98             "<----- halignment = %s ----->\nvalignment = %s",

    99             linealigns[c], haligns[b], valigns[a]);

   100         show_text (toverlay, s, valigns[a], haligns[b], linealigns[c]);

   101         g_free (s);

   102       }

   103     }

   104   }

   105 

   106   return 0;

   107 }