demux: dash: add fixed rate adaptation policy

modules/stream_filter/dash/adaptationlogic/AdaptationLogicFactory.cpp

@@ -39,9 +39,10 @@ IAdaptationLogic* AdaptationLogicFactory::create ( IAdaptationLogic::LogicType l
     switch(logic)
     {
         case IAdaptationLogic::AlwaysBest:      return new AlwaysBestAdaptationLogic    (mpd);
-        case IAdaptationLogic::RateBased:       return new RateBasedAdaptationLogic     (mpd);
         case IAdaptationLogic::AlwaysLowest:    return new AlwaysLowestAdaptationLogic  (mpd);
+        case IAdaptationLogic::FixedRate:       return new FixedRateAdaptationLogic     (mpd);
         case IAdaptationLogic::Default:
+        case IAdaptationLogic::RateBased:       return new RateBasedAdaptationLogic     (mpd);
         default:
             return NULL;
     }

modules/stream_filter/dash/adaptationlogic/IAdaptationLogic.h

@@ -44,7 +44,8 @@ namespace dash
                     Default,
                     AlwaysBest,
                     AlwaysLowest,
-                    RateBased
+                    RateBased,
+                    FixedRate
                 };
 
                 virtual dash::http::Chunk*                  getNextChunk            (Streams::Type) = 0;

modules/stream_filter/dash/adaptationlogic/RateBasedAdaptationLogic.cpp

@@ -76,3 +76,25 @@ void RateBasedAdaptationLogic::updateDownloadRate(size_t size, mtime_t time)
     if(bpsSamplecount % 5 == 0)
         currentBps = bpsAvg;
 }
+
+FixedRateAdaptationLogic::FixedRateAdaptationLogic(mpd::MPD *mpd) :
+    AbstractAdaptationLogic(mpd)
+{
+    currentBps = var_InheritInteger( mpd->getVLCObject(), "dash-prefbw" ) * 8192;
+}
+
+Representation *FixedRateAdaptationLogic::getCurrentRepresentation(Streams::Type type) const
+{
+    if(currentPeriod == NULL)
+        return NULL;
+
+    RepresentationSelector selector;
+    Representation *rep = selector.select(currentPeriod, type, currentBps);
+    if ( rep == NULL )
+    {
+        rep = selector.select(currentPeriod, type);
+        if ( rep == NULL )
+            return NULL;
+    }
+    return rep;
+}

modules/stream_filter/dash/adaptationlogic/RateBasedAdaptationLogic.h

@@ -48,6 +48,17 @@ namespace dash
                 size_t                  bpsSamplecount;
                 size_t                  currentBps;
         };
+
+        class FixedRateAdaptationLogic : public AbstractAdaptationLogic
+        {
+            public:
+                FixedRateAdaptationLogic(mpd::MPD *mpd);
+
+                dash::mpd::Representation *getCurrentRepresentation(Streams::Type) const;
+
+            private:
+                size_t                  currentBps;
+        };
     }
 }
 

modules/stream_filter/dash/dash.cpp

@@ -55,6 +55,9 @@ static void Close   (vlc_object_t *);
 #define DASH_HEIGHT_TEXT N_("Preferred Height")
 #define DASH_HEIGHT_LONGTEXT N_("Preferred Height")
 
+#define DASH_BW_TEXT N_("Fixed Bandwidth in KiB/s")
+#define DASH_BW_LONGTEXT N_("Preferred bandwidth for non adaptative streams")
+
 vlc_module_begin ()
         set_shortname( N_("DASH"))
         set_description( N_("Dynamic Adaptive Streaming over HTTP") )
@@ -63,6 +66,7 @@ vlc_module_begin ()
         set_subcategory( SUBCAT_INPUT_DEMUX )
         add_integer( "dash-prefwidth",  480, DASH_WIDTH_TEXT,  DASH_WIDTH_LONGTEXT,  true )
         add_integer( "dash-prefheight", 360, DASH_HEIGHT_TEXT, DASH_HEIGHT_LONGTEXT, true )
+        add_integer( "dash-prefbw",     250, DASH_BW_TEXT,     DASH_BW_LONGTEXT,     false )
         set_callbacks( Open, Close )
 vlc_module_end ()
 
@@ -105,7 +109,7 @@ static int Open(vlc_object_t *p_obj)
 
     p_sys->p_mpd = mpd;
     dash::DASHManager*p_dashManager = new dash::DASHManager(p_sys->p_mpd,
-                                          dash::logic::IAdaptationLogic::AlwaysLowest,
+                                          dash::logic::IAdaptationLogic::Default,
                                           p_demux->s);
 
     dash::mpd::Period *period = mpd->getFirstPeriod();