modules/access/timecode.c

   1 /**
   2  * @file timecode.c
   3  * @brief Time code sub-picture generator for VLC media player
   4  */
   5 /*****************************************************************************
   6  * Copyright © 2013 Rémi Denis-Courmont
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU Lesser General Public License as published by
  10  * the Free Software Foundation; either version 2.1 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program; if not, write to the Free Software Foundation,
  20  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  21  *****************************************************************************/
  22
  23 #ifdef HAVE_CONFIG_H
  24 # include <config.h>
  25 #endif
  26
  27 #include <stdlib.h>
  28 #include <assert.h>
  29
  30 #include <vlc_common.h>
  31 #include <vlc_demux.h>
  32 #include <vlc_plugin.h>
  33
  34 #define FPS_TEXT N_("Frame rate")
  35
  36 static int  Open (vlc_object_t *);
  37
  38 static const char *const fps_values[] = { "24/1", "25/1", "30000/1001", "30/1" };
  39 static const char *const fps_texts[] = { "24", "25", "29.97", "30" };
  40
  41 vlc_module_begin ()
  42     set_shortname (N_("Time code"))
  43     set_description (N_("Time code subpicture elementary stream generator"))
  44     set_category (CAT_INPUT)
  45     set_subcategory (SUBCAT_INPUT_ACCESS)
  46     set_capability ("access", 0)
  47     set_callbacks (Open, NULL)
  48
  49     add_string ("timecode-fps", "25/1", FPS_TEXT, FPS_TEXT, false)
  50         change_string_list (fps_values, fps_texts)
  51         change_safe ()
  52 vlc_module_end ()
  53
  54 typedef struct
  55 {
  56     es_out_id_t *es;
  57     date_t date;
  58     mtime_t next_time;
  59 } demux_sys_t;
  60
  61 static int DemuxOnce (demux_t *demux, bool master)
  62 {
  63     demux_sys_t *sys = demux->p_sys;
  64     mtime_t pts = date_Get (&sys->date);
  65     lldiv_t d;
  66     unsigned h, m, s, f;
  67
  68     d = lldiv (pts, CLOCK_FREQ);
  69     f = d.rem * sys->date.i_divider_num / sys->date.i_divider_den / CLOCK_FREQ;
  70     d = lldiv (d.quot, 60);
  71     s = d.rem;
  72     d = lldiv (d.quot, 60);
  73     m = d.rem;
  74     h = d.quot;
  75
  76     char *str;
  77     int len = asprintf (&str, "%02u:%02u:%02u:%02u", h, m, s, f);
  78     if (len == -1)
  79         return -1;
  80
  81     block_t *block = block_heap_Alloc (str, len + 1);
  82     if (unlikely(block == NULL))
  83         return -1;
  84
  85     block->i_buffer = len;
  86     assert(str[len] == '\0');
  87
  88     block->i_pts = block->i_dts = pts;
  89     block->i_length = date_Increment (&sys->date, 1) - pts;
  90     es_out_Send (demux->out, sys->es, block);
  91     if (master)
  92         es_out_SetPCR(demux->out, pts);
  93     return 1;
  94 }
  95
  96 static int Demux (demux_t *demux)
  97 {
  98     demux_sys_t *sys = demux->p_sys;
  99
 100     if (sys->next_time == VLC_TS_INVALID) /* Master mode */
 101         return DemuxOnce (demux, true);
 102
 103     /* Slave mode */
 104     while (sys->next_time > date_Get (&sys->date))
 105     {
 106         int val = DemuxOnce (demux, false);
 107         if (val <= 0)
 108             return val;
 109     }
 110     return 1;
 111 }
 112
 113 static int Control (demux_t *demux, int query, va_list args)
 114 {
 115     demux_sys_t *sys = demux->p_sys;
 116
 117     switch (query)
 118     {
 119         case DEMUX_GET_POSITION:
 120             *va_arg (args, float *) = 0.f;
 121             break;
 122
 123         case DEMUX_GET_LENGTH:
 124             *va_arg (args, int64_t *) = INT64_C(0);
 125             break;
 126
 127         case DEMUX_GET_TIME:
 128             *va_arg (args, int64_t *) = date_Get (&sys->date);
 129             break;
 130
 131         case DEMUX_SET_TIME:
 132             date_Set (&sys->date, va_arg (args, int64_t));
 133             break;
 134
 135         case DEMUX_SET_NEXT_DEMUX_TIME:
 136         {
 137             const mtime_t pts = va_arg (args, int64_t );
 138
 139             if (sys->next_time == VLC_TS_INVALID) /* first invocation? */
 140             {
 141                 date_Set (&sys->date, pts);
 142                 date_Decrement (&sys->date, 1);
 143             }
 144             sys->next_time = pts;
 145             break;
 146         }
 147
 148         case DEMUX_GET_PTS_DELAY:
 149         {
 150             int64_t *v = va_arg (args, int64_t *);
 151             *v = INT64_C(1000) * var_InheritInteger (demux, "live-caching");
 152             break;
 153         }
 154
 155         case DEMUX_CAN_PAUSE:
 156         case DEMUX_CAN_CONTROL_PACE:
 157         case DEMUX_CAN_SEEK:
 158             *va_arg (args, bool *) = true;
 159             break;
 160
 161         default:
 162             return VLC_EGENERIC;
 163     }
 164     return VLC_SUCCESS;
 165 }
 166
 167 static int Open (vlc_object_t *obj)
 168 {
 169     demux_t *demux = (demux_t *)obj;
 170     if (demux->out == NULL)
 171         return VLC_EGENERIC;
 172
 173     demux_sys_t *sys = vlc_obj_malloc(obj, sizeof (*sys));
 174     if (unlikely(sys == NULL))
 175         return VLC_ENOMEM;
 176
 177     es_format_t fmt;
 178     es_format_Init (&fmt, SPU_ES, VLC_CODEC_ITU_T140);
 179     sys->es = es_out_Add (demux->out, &fmt);
 180
 181     unsigned num, den;
 182     if (var_InheritURational (demux, &num, &den, "timecode-fps")
 183      || !num || !den)
 184     {
 185         msg_Err (demux, "invalid frame rate");
 186         return VLC_EGENERIC;
 187     }
 188
 189     date_Init (&sys->date, num, den);
 190     date_Set (&sys->date, VLC_TS_0);
 191     sys->next_time = VLC_TS_INVALID;
 192
 193     demux->p_sys = sys;
 194     demux->pf_demux   = Demux;
 195     demux->pf_control = Control;
 196     return VLC_SUCCESS;
 197 }