transcode: fully drain the video filters as normal outputs on EOS/flush

modules/stream_out/transcode/video.c

@@ -433,6 +433,40 @@ static void tag_last_block_with_flag( block_t **out, int i_flag )
     }
 }
 
+static void DrainFilters( sout_stream_id_sys_t *id, block_t **out )
+{
+    filter_chain_t * chains[] = { id->p_f_chain,
+                                  id->p_uf_chain,
+                                  id->p_final_conv_static };
+    picture_t * p_in = NULL;
+    do
+    {
+        for( size_t i=0; i<ARRAY_SIZE(chains); i++ )
+        {
+            if( !chains[i] )
+                continue;
+            if ( p_in )
+                p_in = filter_chain_VideoFilter( chains[i], p_in );
+            else
+                p_in = filter_chain_VideoDrain( chains[i], true );
+        }
+
+        if( !p_in )
+            break;
+
+        /* Blend subpictures */
+        p_in = RenderSubpictures( id, p_in );
+
+        if( p_in )
+        {
+            block_t *p_encoded = transcode_encoder_encode( id->encoder, p_in );
+            if( p_encoded )
+                block_ChainAppend( out, p_encoded );
+            picture_Release( p_in );
+        }
+    } while (p_in != NULL);
+}
+
 int transcode_video_process( sout_stream_t *p_stream, sout_stream_id_sys_t *id,
                                     block_t *in, block_t **out )
 {
@@ -476,6 +510,7 @@ int transcode_video_process( sout_stream_t *p_stream, sout_stream_id_sys_t *id,
                             id->decoder_out.video.i_sar_num, p_pic->format.i_sar_num,
                             id->decoder_out.video.i_sar_den, p_pic->format.i_sar_den
                         );
+                DrainFilters( id, out );
                 /* Close filters, encoder format input can't change */
                 transcode_remove_filters( &id->p_f_chain );
                 transcode_remove_filters( &id->p_uf_chain );
@@ -606,6 +641,7 @@ int transcode_video_process( sout_stream_t *p_stream, sout_stream_id_sys_t *id,
         if( b_eos )
         {
             msg_Info( p_stream, "Drain/restart on EOS" );
+            DrainFilters( id, out );
             if( transcode_encoder_drain( id->encoder, out ) != VLC_SUCCESS )
                 goto error;
             transcode_encoder_close( id->encoder );
@@ -634,6 +670,7 @@ error:
     if( unlikely( !id->b_error && in == NULL ) && transcode_encoder_opened( id->encoder ) )
     {
         msg_Dbg( p_stream, "Flushing thread and waiting that");
+        DrainFilters( id, out );
         if( transcode_encoder_drain( id->encoder, out ) == VLC_SUCCESS )
             msg_Dbg( p_stream, "Flushing done");
         else