src/video_output/video_text.c

   1 /*****************************************************************************
   2  * video_text.c : OSD text manipulation functions
   3  *****************************************************************************
   4  * Copyright (C) 1999-2010 VLC authors and VideoLAN
   5  *
   6  * Author: Sigmund Augdal Helberg <dnumgis@videolan.org>
   7  *         Laurent Aimar <fenrir _AT_ videolan _DOT_ org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 #ifdef HAVE_CONFIG_H
  25 # include "config.h"
  26 #endif
  27 #include <assert.h>
  28
  29 #include <vlc_common.h>
  30 #include <vlc_vout.h>
  31 #include <vlc_vout_osd.h>
  32
  33 typedef struct {
  34     int  position;
  35     char *text;
  36 } osd_spu_updater_sys_t;
  37
  38 static int OSDTextValidate(subpicture_t *subpic,
  39                            bool has_src_changed, const video_format_t *fmt_src,
  40                            bool has_dst_changed, const video_format_t *fmt_dst,
  41                            vlc_tick_t ts)
  42 {
  43     VLC_UNUSED(subpic); VLC_UNUSED(ts);
  44     VLC_UNUSED(fmt_src); VLC_UNUSED(has_src_changed);
  45     VLC_UNUSED(fmt_dst);
  46
  47     if( !has_dst_changed )
  48         return VLC_SUCCESS;
  49     return VLC_EGENERIC;
  50 }
  51
  52 static void OSDTextUpdate(subpicture_t *subpic,
  53                           const video_format_t *fmt_src,
  54                           const video_format_t *fmt_dst,
  55                           vlc_tick_t ts)
  56 {
  57     osd_spu_updater_sys_t *sys = subpic->updater.p_sys;
  58     VLC_UNUSED(fmt_src); VLC_UNUSED(ts);
  59
  60     if( fmt_dst->i_sar_num <= 0 || fmt_dst->i_sar_den <= 0 )
  61         return;
  62
  63     subpic->b_absolute = false;
  64     subpic->i_original_picture_width  = fmt_dst->i_visible_width * fmt_dst->i_sar_num / fmt_dst->i_sar_den;
  65     subpic->i_original_picture_height = fmt_dst->i_visible_height;
  66
  67     video_format_t fmt;
  68     video_format_Init( &fmt, VLC_CODEC_TEXT);
  69     fmt.i_sar_num = 1;
  70     fmt.i_sar_den = 1;
  71
  72     subpicture_region_t *r = subpic->p_region = subpicture_region_New(&fmt);
  73     if (!r)
  74         return;
  75
  76     r->p_text = text_segment_New( sys->text );
  77
  78     const float margin_ratio = 0.04;
  79     const int   margin_h     = margin_ratio * fmt_dst->i_visible_width;
  80     const int   margin_v     = margin_ratio * fmt_dst->i_visible_height;
  81
  82     r->i_text_align = sys->position;
  83     r->i_align = sys->position;
  84     r->i_x = 0;
  85     if (r->i_align & SUBPICTURE_ALIGN_LEFT)
  86         r->i_x += margin_h + fmt_dst->i_x_offset;
  87     else if (r->i_align & SUBPICTURE_ALIGN_RIGHT)
  88         r->i_x += margin_h - fmt_dst->i_x_offset;
  89
  90     r->i_y = 0;
  91     if (r->i_align & SUBPICTURE_ALIGN_TOP )
  92         r->i_y += margin_v + fmt_dst->i_y_offset;
  93     else if (r->i_align & SUBPICTURE_ALIGN_BOTTOM )
  94         r->i_y += margin_v - fmt_dst->i_y_offset;
  95 }
  96
  97 static void OSDTextDestroy(subpicture_t *subpic)
  98 {
  99     osd_spu_updater_sys_t *sys = subpic->updater.p_sys;
 100
 101     free(sys->text);
 102     free(sys);
 103 }
 104
 105 void vout_OSDText(vout_thread_t *vout, int channel,
 106                    int position, vlc_tick_t duration, const char *text)
 107 {
 108     assert( (position & ~SUBPICTURE_ALIGN_MASK) == 0);
 109     if (!var_InheritBool(vout, "osd") || duration <= 0)
 110         return;
 111
 112     osd_spu_updater_sys_t *sys = malloc(sizeof(*sys));
 113     if (!sys)
 114         return;
 115     sys->position = position;
 116     sys->text     = strdup(text);
 117
 118     subpicture_updater_t updater = {
 119         .pf_validate = OSDTextValidate,
 120         .pf_update   = OSDTextUpdate,
 121         .pf_destroy  = OSDTextDestroy,
 122         .p_sys       = sys,
 123     };
 124     subpicture_t *subpic = subpicture_New(&updater);
 125     if (!subpic) {
 126         free(sys->text);
 127         free(sys);
 128         return;
 129     }
 130
 131     subpic->i_channel  = channel;
 132     subpic->i_start    = vlc_tick_now();
 133     subpic->i_stop     = subpic->i_start + duration;
 134     subpic->b_ephemer  = true;
 135     subpic->b_absolute = false;
 136     subpic->b_fade     = true;
 137
 138     vout_PutSubpicture(vout, subpic);
 139 }
 140
 141 void vout_OSDMessageVa(vout_thread_t *vout, int channel,
 142                        const char *format, va_list args)
 143 {
 144     char *string;
 145     if (vasprintf(&string, format, args) != -1) {
 146         vout_OSDText(vout, channel,
 147                      SUBPICTURE_ALIGN_TOP|SUBPICTURE_ALIGN_RIGHT, VLC_TICK_FROM_SEC(1),
 148                      string);
 149         free(string);
 150     }
 151 }