* modules/audio_output/directx.c: fixed the way we get the current latency in...

* modules/audio_output/directx.c: fixed the way we get the current latency in the driver. fixes the continuous resampling issues with s16l and might also fix the fl32 problems. This needs some heavy testing.

modules/audio_output/directx.c

@@ -38,8 +38,8 @@
 #include <mmsystem.h>
 #include <dsound.h>
 
-#define FRAME_SIZE 2048              /* The size is in samples, not in bytes */
-#define FRAMES_NUM 8
+#define FRAME_SIZE ((int)p_aout->output.output.i_rate/20) /* Size in samples */
+#define FRAMES_NUM 8                                      /* Needs to be > 3 */
 
 /* frame buffer status */
 #define FRAME_QUEUED 0
@@ -1038,7 +1038,7 @@ static void DirectSoundThread( notification_thread_t *p_notif )
     HANDLE  notification_events[FRAMES_NUM];
     HRESULT dsresult;
     aout_instance_t *p_aout = p_notif->p_aout;
-    int i, i_which_frame, i_last_frame, i_next_frame;
+    int i, i_which_frame, i_last_frame;
     mtime_t mtime;
     vlc_bool_t b_sleek;
 
@@ -1083,7 +1083,7 @@ static void DirectSoundThread( notification_thread_t *p_notif )
     while( !p_notif->b_die )
     {
         aout_buffer_t *p_buffer;
-        long l_latency;
+        long l_position, l_latency = 0;
 
         /* wait for the position notification */
         i_which_frame = WaitForMultipleObjects( FRAMES_NUM,
@@ -1098,52 +1098,43 @@ static void DirectSoundThread( notification_thread_t *p_notif )
         /* We take into account the current latency */
         if SUCCEEDED( IDirectSoundBuffer_GetCurrentPosition(
                         p_aout->output.p_sys->p_dsbuffer,
-                        &l_latency, NULL ) )
+                        &l_position, NULL ) )
         {
-            if( l_latency > (i_which_frame * FRAME_SIZE)
-                  && l_latency < ((i_which_frame+1) * FRAME_SIZE) )
-            {
-                l_latency = - ( l_latency /
-                                p_aout->output.output.i_bytes_per_frame %
-                                FRAME_SIZE );
-            }
-            else
-            {
-                l_latency = FRAME_SIZE - ( l_latency /
-                                      p_aout->output.output.i_bytes_per_frame %
-                                      FRAME_SIZE );
-            }
-        }
-        else
-        {
-            l_latency = 0;
+            /* Latency is in samples */
+            l_position /= p_aout->output.output.i_bytes_per_frame;
+            l_latency = l_position - i_which_frame * FRAME_SIZE;
+
+            /* That sucks but latency can apparently be negative up to -FRAME_SIZE
+             * ie. the notification is done in advance. */
+            if( l_latency > FRAME_SIZE * (FRAMES_NUM-1) )
+                l_latency -= (FRAME_SIZE * FRAMES_NUM);
+            else if( l_latency < -FRAME_SIZE )
+                l_latency += (FRAME_SIZE * FRAMES_NUM);
         }
 
         /* Mark last frame as empty */
         i_last_frame = (i_which_frame + FRAMES_NUM -1) % FRAMES_NUM;
-        i_next_frame = (i_which_frame + 1) % FRAMES_NUM;
         p_notif->i_frame_status[i_last_frame] = FRAME_EMPTY;
 
         /* Try to fill in as many frame buffers as possible */
-        for( i = i_next_frame; (i % FRAMES_NUM) != i_which_frame; i++ )
+        for( i = i_which_frame + 1; i < i_which_frame + FRAMES_NUM; i++ )
         {
-
             /* Check if frame buf is already filled */
             if( p_notif->i_frame_status[i % FRAMES_NUM] == FRAME_QUEUED )
                 continue;
 
+            if( ((i - i_which_frame) * FRAME_SIZE - l_latency) < 0 )
+            {
+                msg_Warn( p_aout, "dectected underrun!");
+            }
+
             p_buffer = aout_OutputNextBuffer( p_aout,
-                mtime + 1000000 / p_aout->output.output.i_rate *
-                ((i - i_next_frame + 1) * FRAME_SIZE + l_latency), b_sleek );
+                mtime + I64C(1000000) * ((i - i_which_frame) * FRAME_SIZE -
+                l_latency) / p_aout->output.output.i_rate, b_sleek );
 
             /* If there is no audio data available and we have some buffered
              * already, then just wait for the next time */
-            if( !p_buffer && (i != i_next_frame) )
-            {
-                //msg_Err( p_aout, "only %i frame buffers filled!",
-                //         i - i_next_frame );
-                break;
-            }
+            if( !p_buffer && (i != i_which_frame + 1) ) break;
 
             if( FillBuffer( p_aout, (i%FRAMES_NUM), p_buffer )
                 != VLC_SUCCESS )