Improve frame-dropping in decklink.

diff --git a/src/modules/decklink/consumer_decklink.cpp b/src/modules/decklink/consumer_decklink.cpp
index ea5d368a32b7b4cf06b0734c05aade924aedd483..b2c4c2c513c9e2285120344cb007c62a6323cb64 100644 (file)
--- a/src/modules/decklink/consumer_decklink.cpp
+++ b/src/modules/decklink/consumer_decklink.cpp
@@ -98,6 +98,8 @@ private:
        int                         m_channels;
        uint32_t                    m_maxAudioBuffer;
        mlt_deque                   m_videoFrameQ;
+       mlt_frame                   m_frame;
+       unsigned                    m_dropped;
                
        IDeckLinkDisplayMode* getDisplayMode()
        {
@@ -218,6 +220,8 @@ public:
                m_preroll = preroll < PREROLL_MINIMUM ? PREROLL_MINIMUM : preroll;
                m_count = 0;
                m_deckLinkOutput->BeginAudioPreroll();
+               m_frame = 0;
+               m_dropped = 0;
                
                return true;
        }
@@ -258,6 +262,7 @@ public:
                }
                m_videoFrame = 0;
                if ( m_fifo ) sample_fifo_close( m_fifo );
+               mlt_frame_close( m_frame );
        }
        
        void createFrame()
@@ -345,29 +350,33 @@ public:
                        }
                }
                
-               // Get the video
                if ( mlt_properties_get_int( MLT_FRAME_PROPERTIES( frame ), "rendered") )
                {
-                       mlt_image_format format = mlt_image_yuv422;
-                       uint8_t* image = 0;
-                       uint8_t* buffer = 0;
-
-                       if ( !mlt_frame_get_image( frame, &image, &format, &m_width, &m_height, 0 ) )
-                       {
-                               m_videoFrame = (IDeckLinkMutableVideoFrame*) mlt_deque_pop_back( m_videoFrameQ );
-                               m_videoFrame->GetBytes( (void**) &buffer );
-                               if ( m_displayMode->GetFieldDominance() == bmdUpperFieldFirst )
-                                       // convert lower field first to top field first
-                                       swab( image, buffer + m_width * 2, m_width * ( m_height - 1 ) * 2 );
-                               else
-                                       swab( image, buffer, m_width * m_height * 2 );
-                               m_deckLinkOutput->ScheduleVideoFrame( m_videoFrame, m_count * m_duration, m_duration, m_timescale );
-                               mlt_deque_push_front( m_videoFrameQ, m_videoFrame );
-                       }
+                       // Close the previous frame and use the new one
+                       mlt_frame_close( m_frame );
+                       m_frame = frame;
                }
                else
                {
-                       mlt_log_verbose( &m_consumer, "dropped video frame\n" );
+                       // Reuse the last frame
+                       mlt_log_verbose( &m_consumer, "dropped video frame %u\n", ++m_dropped );
+               }
+
+               // Get the video
+               mlt_image_format format = mlt_image_yuv422;
+               uint8_t* image = 0;
+               uint8_t* buffer = 0;
+               if ( !mlt_frame_get_image( m_frame, &image, &format, &m_width, &m_height, 0 ) )
+               {
+                       m_videoFrame = (IDeckLinkMutableVideoFrame*) mlt_deque_pop_back( m_videoFrameQ );
+                       m_videoFrame->GetBytes( (void**) &buffer );
+                       if ( m_displayMode->GetFieldDominance() == bmdUpperFieldFirst )
+                               // convert lower field first to top field first
+                               swab( image, buffer + m_width * 2, m_width * ( m_height - 1 ) * 2 );
+                       else
+                               swab( image, buffer, m_width * m_height * 2 );
+                       m_deckLinkOutput->ScheduleVideoFrame( m_videoFrame, m_count * m_duration, m_duration, m_timescale );
+                       mlt_deque_push_front( m_videoFrameQ, m_videoFrame );
                }
                ++m_count;
 
@@ -472,7 +481,6 @@ static void *run( void *arg )
                        
                        // Close the frame
                        mlt_events_fire( properties, "consumer-frame-show", frame, NULL );
-                       mlt_frame_close( frame );
                }
        }