Subsync: added an easier way to sync subtitles

Added the following shortcuts (and made them configurable):
 - Shift-H: sets a timestamp bookmark on the audio
 - Shift-J: sets a timestamp bookmark on the subtitle
 - Shift-K: corrects the delay between both bookmarks
 - Command-Shift-K: resets the delay

See http://forum.videolan.org/viewtopic.php?f=7&t=109641 for an
illustration of a possible use
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

include/vlc_keys.h

@@ -162,6 +162,10 @@ typedef enum vlc_action {
     ACTIONID_PLAY_CLEAR,
     ACTIONID_SUBDELAY_UP,
     ACTIONID_SUBDELAY_DOWN,
+    ACTIONID_SUBSYNC_MARKAUDIO,
+    ACTIONID_SUBSYNC_MARKSUB,
+    ACTIONID_SUBSYNC_APPLY,
+    ACTIONID_SUBSYNC_RESET,
     ACTIONID_SUBPOS_UP,
     ACTIONID_SUBPOS_DOWN,
     ACTIONID_AUDIO_TRACK,

modules/control/hotkeys.c

@@ -48,6 +48,13 @@ struct intf_sys_t
 {
     vout_thread_t      *p_last_vout;
     int slider_chan;
+
+    /*subtitle_delaybookmarks: placeholder for storing subtitle sync timestamps*/
+    struct
+    {
+        int64_t i_time_subtitle;
+        int64_t i_time_audio;
+    } subtitle_delaybookmarks;
 };
 
 /*****************************************************************************
@@ -101,6 +108,8 @@ static int Open( vlc_object_t *p_this )
     p_intf->p_sys = p_sys;
 
     p_sys->p_last_vout = NULL;
+    p_sys->subtitle_delaybookmarks.i_time_audio = 0;
+    p_sys->subtitle_delaybookmarks.i_time_subtitle = 0;
 
     var_AddCallback( p_intf->p_libvlc, "key-action", ActionEvent, p_intf );
     return VLC_SUCCESS;
@@ -373,6 +382,62 @@ static int PutAction( intf_thread_t *p_intf, int i_action )
             }
             break;
 
+        case ACTIONID_SUBSYNC_MARKAUDIO:
+        {
+            p_sys->subtitle_delaybookmarks.i_time_audio = mdate();
+            DisplayMessage( p_vout, _("Sub sync: bookmarked audio timestamp"));
+            break;
+        }
+        case ACTIONID_SUBSYNC_MARKSUB:
+        {
+            p_sys->subtitle_delaybookmarks.i_time_subtitle = mdate();
+            DisplayMessage( p_vout, _("Sub sync: bookmarked subtitle timestamp"));
+            break;
+        }
+        case ACTIONID_SUBSYNC_APPLY:
+        {
+            /* Warning! Can yield a pause in the playback.
+             * For example, the following succession of actions will yield a 5 second delay :
+             * - Pressing Shift-H (ACTIONID_SUBSYNC_MARKAUDIO)
+             * - wait 5 second
+             * - Press Shift-J (ACTIONID_SUBSYNC_MARKSUB)
+             * - Press Shift-K (ACTIONID_SUBSYNC_APPLY)
+             * --> 5 seconds pause
+             * This is due to var_SetTime() (and ultimately UpdatePtsDelay())
+             * which causes the video to pause for an equivalent duration
+             * (This problem is also present in the "Track synchronization" window) */
+            if ( p_input )
+            {
+                if ( (p_sys->subtitle_delaybookmarks.i_time_audio == 0) || (p_sys->subtitle_delaybookmarks.i_time_subtitle == 0) )
+                {
+                    DisplayMessage( p_vout, _( "Sub sync: set bookmarks first!" ) );
+                }
+                else
+                {
+                    int64_t i_current_subdelay = var_GetTime( p_input, "spu-delay" );
+                    int64_t i_additional_subdelay = p_sys->subtitle_delaybookmarks.i_time_audio - p_sys->subtitle_delaybookmarks.i_time_subtitle;
+                    int64_t i_total_subdelay = i_current_subdelay + i_additional_subdelay;
+                    var_SetTime( p_input, "spu-delay", i_total_subdelay);
+                    ClearChannels( p_intf, p_vout );
+                    DisplayMessage( p_vout, _( "Sub sync: corrected %i ms (total delay = %i ms)" ),
+                                            (int)(i_additional_subdelay / 1000),
+                                            (int)(i_total_subdelay / 1000) );
+                    p_sys->subtitle_delaybookmarks.i_time_audio = 0;
+                    p_sys->subtitle_delaybookmarks.i_time_subtitle = 0;
+                }
+            }
+            break;
+        }
+        case ACTIONID_SUBSYNC_RESET:
+        {
+            var_SetTime( p_input, "spu-delay", 0);
+            ClearChannels( p_intf, p_vout );
+            DisplayMessage( p_vout, _( "Sub sync: delay reset" ) );
+            p_sys->subtitle_delaybookmarks.i_time_audio = 0;
+            p_sys->subtitle_delaybookmarks.i_time_subtitle = 0;
+            break;
+        }
+
         case ACTIONID_SUBDELAY_DOWN:
         case ACTIONID_SUBDELAY_UP:
         {

src/config/keys.c

@@ -347,6 +347,10 @@ static const struct action actions[] =
     { "subdelay-up", ACTIONID_SUBDELAY_UP, },
     { "subpos-down", ACTIONID_SUBPOS_DOWN, },
     { "subpos-up", ACTIONID_SUBPOS_UP, },
+    { "subsync-apply", ACTIONID_SUBSYNC_APPLY, },
+    { "subsync-markaudio", ACTIONID_SUBSYNC_MARKAUDIO, },
+    { "subsync-marksub", ACTIONID_SUBSYNC_MARKSUB, },
+    { "subsync-reset", ACTIONID_SUBSYNC_RESET, },
     { "subtitle-track", ACTIONID_SUBTITLE_TRACK, },
     { "title-next", ACTIONID_TITLE_NEXT, },
     { "title-prev", ACTIONID_TITLE_PREV, },

src/libvlc-module.c

@@ -1310,6 +1310,14 @@ static const char *const mouse_wheel_texts[] =
 #define SUBDELAY_UP_KEY_LONGTEXT N_("Select the key to increase the subtitle delay.")
 #define SUBDELAY_DOWN_KEY_TEXT N_("Subtitle delay down")
 #define SUBDELAY_DOWN_KEY_LONGTEXT N_("Select the key to decrease the subtitle delay.")
+#define SUBSYNC_MARKAUDIO_KEY_TEXT N_("Subtitle sync / bookmark audio timestamp")
+#define SUBSYNC_MARKAUDIO_KEY_LONGTEXT N_("Select the key to bookmark audio timestamp when syncing subtitles.")
+#define SUBSYNC_MARKSUB_KEY_TEXT N_("Subtitle sync / bookmark subtitle timestamp")
+#define SUBSYNC_MARKSUB_KEY_LONGTEXT N_("Select the key to bookmark subtitle timestamp when syncing subtitles.")
+#define SUBSYNC_APPLY_KEY_TEXT N_("Subtitle sync / synchronize audio & subtitle timestamps")
+#define SUBSYNC_APPLY_KEY_LONGTEXT N_("Select the key to synchronize bookmarked audio & subtitle timestamps.")
+#define SUBSYNC_RESET_KEY_TEXT N_("Subtitle sync / reset audio & subtitle synchronization")
+#define SUBSYNC_RESET_KEY_LONGTEXT N_("Select the key to reset synchronization of audio & subtitle timestamps.")
 #define SUBPOS_UP_KEY_TEXT N_("Subtitle position up")
 #define SUBPOS_UP_KEY_LONGTEXT N_("Select the key to move subtitles higher.")
 #define SUBPOS_DOWN_KEY_TEXT N_("Subtitle position down")
@@ -2182,6 +2190,10 @@ vlc_module_begin ()
 #   define KEY_SUBDELAY_DOWN      "h"
 #   define KEY_SUBPOS_DOWN        NULL
 #   define KEY_SUBPOS_UP          NULL
+#   define KEY_SUBSYNC_MARKAUDIO  "Shift+h"
+#   define KEY_SUBSYNC_MARKSUB    "Shift+j"
+#   define KEY_SUBSYNC_APPLY      "Shift+k"
+#   define KEY_SUBSYNC_RESET      "Command+Shift+k"
 #   define KEY_AUDIODELAY_UP      "g"
 #   define KEY_AUDIODELAY_DOWN    "f"
 #   define KEY_AUDIO_TRACK        "l"
@@ -2293,6 +2305,10 @@ vlc_module_begin ()
 #   define KEY_SUBDELAY_DOWN      "g"
 #   define KEY_SUBPOS_DOWN        NULL
 #   define KEY_SUBPOS_UP          NULL
+#   define KEY_SUBSYNC_MARKAUDIO  "Shift+h"
+#   define KEY_SUBSYNC_MARKSUB    "Shift+j"
+#   define KEY_SUBSYNC_APPLY      "Shift+k"
+#   define KEY_SUBSYNC_RESET      "Ctrl+Shift+k"
 #   define KEY_AUDIODELAY_UP      "k"
 #   define KEY_AUDIODELAY_DOWN    "j"
 #   define KEY_RANDOM             "r"
@@ -2448,6 +2464,14 @@ vlc_module_begin ()
              SUBDELAY_UP_KEY_TEXT, SUBDELAY_UP_KEY_LONGTEXT, true )
     add_key( "key-subdelay-down", KEY_SUBDELAY_DOWN,
              SUBDELAY_DOWN_KEY_TEXT, SUBDELAY_DOWN_KEY_LONGTEXT, true )
+    add_key( "key-subsync-markaudio", KEY_SUBSYNC_MARKAUDIO,
+             SUBSYNC_MARKAUDIO_KEY_TEXT, SUBSYNC_MARKAUDIO_KEY_LONGTEXT, true )
+    add_key( "key-subsync-marksub", KEY_SUBSYNC_MARKSUB,
+             SUBSYNC_MARKSUB_KEY_TEXT, SUBSYNC_MARKSUB_KEY_LONGTEXT, true )
+    add_key( "key-subsync-apply", KEY_SUBSYNC_APPLY,
+             SUBSYNC_APPLY_KEY_TEXT, SUBSYNC_APPLY_KEY_LONGTEXT, true )
+     add_key( "key-subsync-reset", KEY_SUBSYNC_RESET,
+              SUBSYNC_RESET_KEY_TEXT, SUBSYNC_RESET_KEY_LONGTEXT, true )
     add_key( "key-subpos-up", KEY_SUBPOS_UP,
              SUBPOS_UP_KEY_TEXT, SUBPOS_UP_KEY_LONGTEXT, true )
     add_key( "key-subpos-down", KEY_SUBPOS_DOWN,