Ticket #2808: time_based_seeking.4.diff

libs/libmythtv/DVDRingBuffer.cpp

@@ -45 +45 @@
       seekpos(0), seekwhence(0), 
       dvdname(NULL), serialnumber(NULL),
       seeking(false), seekTime(0),
+      currentTime(0),
       parent(0)
 {
     memset(&dvdMenuButton, 0, sizeof(AVSubtitle));
@@ -81 +82 @@
 long long DVDRingBufferPriv::Seek(long long time)
 {
     seekTime = (uint64_t)time;
-    uint offset_divider = 1;
+    uint searchToCellStart = 1;
     int ffrewSkip = 1;
     if (parent)
         ffrewSkip = parent->GetFFRewSkip();
-    dvdnav_status_t dvdRet = dvdnav_time_search(this->dvdnav, seekTime, offset_divider);
+    if (ffrewSkip != 1)
+        searchToCellStart = 0;
+    dvdnav_status_t dvdRet = 
+        dvdnav_time_search(this->dvdnav, seekTime, searchToCellStart);
     if (dvdRet == DVDNAV_STATUS_ERR)
     {
         VERBOSE(VB_PLAYBACK, LOC_ERR + 
@@ -95 +99 @@
     {
         gotStop = false;
         // TODO: precise seeking too inefficient
-        //if (time > 0 && ffrewSkip == 1)
-        //    seeking = true;
+        if (time > 0 && ffrewSkip == 1)
+            seeking = true;
     }
     
     return currentpos;
@@ -212 +216 @@
         return -1;
     }
 
+    QMutexLocker lock(&seekLock);
     while (needed)
     {
         blockBuf = dvdBlockWriteBuf;
@@ -391 +396 @@
                     }
                 }
 
+                dvd_time_t timeFromCellStart = dsi->dsi_gi.c_eltm;
+                currentTime = cellStart +
+                    (uint)(dvdnav_convert_time(&timeFromCellStart));
                 currentpos = GetReadPosition();
                 
                 if (seeking)
                 {
-                    dvd_time_t timeFromCellStart = dsi->dsi_gi.c_eltm;
-                    uint64_t currentpts = cellStart + 
-                        (uint)dvdnav_convert_time(&timeFromCellStart); 
-                    if (currentpts >= seekTime)
+                    uint relativeTime = (uint)((seekTime - currentTime)/ 90000);
+                    if (relativeTime == 0)
                     {
                         seeking = false;
                         seekTime = 0;
                     }
+                    else
+                        dvdnav_time_search_within_cell(dvdnav, relativeTime);
                 }
                 
                 if (blockBuf != dvdBlockWriteBuf)
@@ -990 +998 @@
 uint DVDRingBufferPriv::GetCurrentTime(void)
 {
     QMutexLocker lock(&seekLock);
-    dsi_t *dvdnavDsi = dvdnav_get_current_nav_dsi(dvdnav);
-    dvd_time_t timeFromCellStart = dvdnavDsi->dsi_gi.c_eltm;
-    uint currentTime = GetCellStart() +
-        (uint)(dvdnav_convert_time(&timeFromCellStart) / 90000);
-    return currentTime;
+    return (currentTime / 90000);
 }
 
 uint DVDRingBufferPriv::GetAudioLanguage(int id)

libs/libmythtv/DVDRingBuffer.h

@@ -160 +160 @@
     QString        serialnumber;
     bool           seeking;
     uint64_t       seekTime;
+    uint           currentTime;
 
     NuppelVideoPlayer *parent;
 

libs/libmythdvdnav/searching.c

@@ -63 +63 @@
   }
   if(admap) {
     uint32_t address = 0;
-    uint32_t vobu_start, next_vobu;
+    uint32_t vobu_start, next_vobu, first_address, last_address;
     int32_t found = 0;
 
     /* Search through ADMAP for best sector */
     vobu_start = SRI_END_OF_CELL;
-    /* FIXME: Implement a faster search algorithm */
-    while((!found) && ((address<<2) < admap->last_byte)) {
-      next_vobu = admap->vobu_start_sectors[address];
+    /* use binary search algorithm to improve efficiency */
+    if (admap->last_byte > 20 && 
+        admap->vobu_start_sectors[20] >= seekto_block)
+    {
+      while((!found) && ((address<<2) < admap->last_byte)) {
+        next_vobu = admap->vobu_start_sectors[address];
 
-      /* fprintf(MSG_OUT, "libdvdnav: Found block %u\n", next_vobu); */
-
-      if (next_vobu == seekto_block) {
-                vobu_start = next_vobu;
-        found = 1;
-      } else if (vobu_start < seekto_block && next_vobu > seekto_block) {
-        found = 1;
-      } else {
-        vobu_start = next_vobu;
+        if (next_vobu == seekto_block) {
+                  vobu_start = next_vobu;
+          found = 1;
+        } else if (vobu_start < seekto_block && next_vobu > seekto_block) {
+          found = 1;
+        } else {
+          vobu_start = next_vobu;
+        }
+        address ++;
       }
-      address ++;
     }
+    else {
+      found = 0;
+      first_address = 0;
+      last_address  = admap->last_byte >> 2;
+      while ((!found) && first_address <= last_address)
+      {
+        address = (first_address + last_address) / 2;
+        next_vobu = admap->vobu_start_sectors[address];
+        if (seekto_block > next_vobu)
+          first_address = address + 1;
+        else if (seekto_block < next_vobu)
+          last_address = address - 1;
+        else {
+          vobu_start = next_vobu;
+          found = 1;
+          break;
+        }
+      }
+    }
     if(found) {
       *vobu = vobu_start;
       return DVDNAV_STATUS_OK;
@@ -97 +118 @@
 }
 
 dvdnav_status_t dvdnav_time_search(dvdnav_t *this,
-                                   uint64_t time, uint offset_divider) {
+                                   uint64_t time, uint search_to_nearest_cell) {
   
   uint64_t target = time;
   uint64_t length = 0;
@@ -110 +131 @@
   
   cell_playback_t *cell;
   dvd_state_t *state;
-  dsi_t *dsi;
   dvdnav_status_t result;
 
   if(this->position_current.still != 0) {
@@ -146 +166 @@
     cell_length = dvdnav_convert_time(&cell->playback_time);
     length += cell_length;
     if (target <= length) {
-      offset = (cell->last_sector - cell->first_sector) / offset_divider;
+      offset = (cell->last_sector - cell->first_sector);
       diff2  = ((double)target - (double)prev_length) / (double)cell_length;
       offset = (diff2 * offset);
       target = cell->first_sector;
-      target += offset;
-      
+      if (!search_to_nearest_cell)
+        target += offset;
       found = 1;
       break;
     }
@@ -619 +639 @@
   
   return DVDNAV_STATUS_OK;
 }
+
+dvdnav_status_t dvdnav_time_search_within_cell(dvdnav_t *this,
+                    uint relative_time)
+{
+  if(!this) {
+    printerr("Passed a NULL pointer.");
+    return DVDNAV_STATUS_ERR;
+  }
+
+  uint32_t cur_vobu, new_vobu, start;
+  int current_cell, i;
+  
+  dsi_t * dsi;
+  dvd_state_t *state;
+  int stime[19] = { 240, 120, 60, 20, 15, 14, 13, 12, 11,
+                    10, 9, 8, 7, 6, 5, 4, 3, 2, 1};
+  pthread_mutex_lock(&this->vm_lock);
+  cur_vobu = this->vobu.vobu_start;
+  for (i = 0; i <= 19; i++) {
+    if (stime[i]/2.0 <= relative_time) {
+      dsi = dvdnav_get_current_nav_dsi(this);
+      new_vobu = cur_vobu + (dsi->vobu_sri.fwda[i] & 0xfffff);
+      break;
+    }
+  }
+  
+  state = &(this->vm->state);
+  current_cell = state->cellN;
+  start =  state->pgc->cell_playback[current_cell-1].first_sector;
+  if (vm_jump_cell_block(this->vm, state->cellN, new_vobu - start)) {
+    this->vm->hop_channel += HOP_SEEK;
+  }
+  pthread_mutex_unlock(&this->vm_lock);
+  return DVDNAV_STATUS_OK;
+}

libs/libmythdvdnav/dvdnav.h

@@ -362 +362 @@
  * Stop playing the current position and start playback of the title
  * from the specified timecode.
  *
- * Currently unimplemented!
+ * if search_to_nearest_cell is set then search to the nearest Cell.
+ * and then use dvdnav_time_search_within_cell for further seeking
+ * Otherwise tries to guess the nearest VOBU by calculating an offset.
  */
 dvdnav_status_t dvdnav_time_search(dvdnav_t *self, 
-                                   uint64_t time, uint offset_divider);
+                                   uint64_t time, uint search_to_nearest_cell);
 
+/* Seeks the nearest VOBU to the relative_time within the cell
+ * relative_time is in seconds
+ */
+dvdnav_status_t dvdnav_time_search_within_cell(dvdnav_t *self,
+                   uint relative_time);
 /*
  * Stop playing current position and play the "GoUp"-program chain.
  * (which generally leads to the title menu or a higer-level menu).