input: es_out: early return

The if else block is followed by a single return, but the else block is
much more complex than the if block. To simplify, we can add the early
return to the first branch as an early success, ie. there is no other
handling necessary for PCR if buffering is still enabled.

src/input/es_out.c

@@ -3399,68 +3399,75 @@ static int EsOutVaControlLocked( es_out_t *out, input_source_t *source,
         {
             /* Check buffering state on master clock update */
             EsOutDecodersStopBuffering( out, false );
+            return VLC_SUCCESS;
         }
-        else if( p_pgrm == p_sys->p_pgrm )
-        {
-            if( p_sys->p_next_frame_es != NULL )
-                return VLC_SUCCESS;
 
-            /* Last pcr/clock update was late. We need to compensate by offsetting
-               from the clock the rendering dates */
-            if( i_late > 0 && ( !priv->p_sout ||
-                            !priv->b_out_pace_control ) )
-            {
-                /* input_clock_GetJitter returns compound delay:
-                 * - initial pts delay (buffering/caching)
-                 * - jitter compensation
-                 * - track offset pts delay
-                 * updated on input_clock_Update
-                 * Late/jitter amount is updated from median of late values */
-                vlc_tick_t i_clock_total_delay = input_clock_GetJitter( p_pgrm->p_input_clock );
-
-                /* Current jitter */
-                vlc_tick_t i_new_jitter = i_clock_total_delay
-                                        - p_sys->i_tracks_pts_delay
-                                        - p_sys->i_pts_delay;
-
-                /* If the clock update is late, we have 2 possibilities:
-                 *  - offset rendering a bit more by increasing the total pts-delay
-                 *  - ignore, set clock to a new reference ahead of previous one
-                 *    and flush buffers (because all previous pts will now be late) */
-
-                /* Avoid dangerously high value */
-                /* If the jitter increase is over our max or the total hits the maximum */
-                if( i_new_jitter > priv->i_jitter_max ||
-                    i_clock_total_delay > INPUT_PTS_DELAY_MAX ||
-                    /* jitter is always 0 due to median calculation first output
-                       and low delay can't allow non reversible jitter increase
-                       in branch below */
-                    (b_low_delay && i_late > priv->i_jitter_max) )
-                {
-                    msg_Err( p_sys->p_input,
-                             "ES_OUT_SET_(GROUP_)PCR  is called %d ms late (jitter of %d ms ignored)",
-                             (int)MS_FROM_VLC_TICK(i_late),
-                             (int)MS_FROM_VLC_TICK(i_new_jitter) );
+        if (p_pgrm != p_sys->p_pgrm || p_sys->p_next_frame_es != NULL)
+            return VLC_SUCCESS;
 
-                    /* don't change the current jitter */
-                    i_new_jitter = p_sys->i_pts_jitter;
-                }
-                else
-                {
-                    msg_Err( p_sys->p_input,
-                             "ES_OUT_SET_(GROUP_)PCR  is called %d ms late (pts_delay increased to %d ms)",
-                             (int)MS_FROM_VLC_TICK(i_late),
-                             (int)MS_FROM_VLC_TICK(i_clock_total_delay) );
-                }
+        /* The PCR is not considered late, there is no compensation needed. */
+        if (i_late <= 0)
+            return VLC_SUCCESS;
 
-                /* Force a rebufferization when we are too late */
-                EsOutControlLocked( out, source, ES_OUT_RESET_PCR );
+        /* The output is paced by another client, there is no clock
+         * compensation possible. */
+        if (priv->p_sout != NULL && priv->b_out_pace_control)
+            return VLC_SUCCESS;
 
-                EsOutPrivControlLocked( out, source, ES_OUT_PRIV_SET_JITTER,
-                                        p_sys->i_pts_delay, i_new_jitter,
-                                        p_sys->i_cr_average );
-            }
+        /* Last pcr/clock update was late. We need to compensate by offsetting
+         * from the clock the rendering dates. */
+
+        /* input_clock_GetJitter returns compound delay:
+         * - initial pts delay (buffering/caching)
+         * - jitter compensation
+         * - track offset pts delay
+         * updated on input_clock_Update
+         * Late/jitter amount is updated from median of late values */
+        vlc_tick_t i_clock_total_delay = input_clock_GetJitter(p_pgrm->p_input_clock);
+
+        /* Current jitter */
+        vlc_tick_t i_new_jitter = i_clock_total_delay
+                                - p_sys->i_tracks_pts_delay
+                                - p_sys->i_pts_delay;
+
+        /* If the clock update is late, we have 2 possibilities:
+         *  - offset rendering a bit more by increasing the total pts-delay
+         *  - ignore, set clock to a new reference ahead of previous one
+         *    and flush buffers (because all previous pts will now be late) */
+
+        /* Avoid dangerously high value */
+        /* If the jitter increase is over our max or the total hits the maximum */
+        if (i_new_jitter > priv->i_jitter_max ||
+            i_clock_total_delay > INPUT_PTS_DELAY_MAX ||
+            /* jitter is always 0 due to median calculation first output
+               and low delay can't allow non reversible jitter increase
+               in branch below */
+            (b_low_delay && i_late > priv->i_jitter_max))
+        {
+
+            msg_Err(p_sys->p_input,
+                    "ES_OUT_SET_(GROUP_)PCR  is called %d ms late (jitter of %d ms ignored)",
+                    (int)MS_FROM_VLC_TICK(i_late),
+                    (int)MS_FROM_VLC_TICK(i_new_jitter));
+
+            /* don't change the current jitter */
+            i_new_jitter = p_sys->i_pts_jitter;
         }
+        else
+        {
+            msg_Err(p_sys->p_input,
+                    "ES_OUT_SET_(GROUP_)PCR  is called %d ms late (pts_delay increased to %d ms)",
+                    (int)MS_FROM_VLC_TICK(i_late),
+                    (int)MS_FROM_VLC_TICK(i_clock_total_delay));
+        }
+
+        /* Force a rebufferization when we are too late */
+        EsOutControlLocked(out, source, ES_OUT_RESET_PCR);
+
+        EsOutPrivControlLocked(out, source, ES_OUT_PRIV_SET_JITTER,
+                               p_sys->i_pts_delay, i_new_jitter,
+                               p_sys->i_cr_average);
+
         return VLC_SUCCESS;
     }