producer_avformat.c: improve frame accuracy

git-svn-id: https://mlt.svn.sourceforge.net/svnroot/mlt/trunk/mlt@1001 d19143bc-622f-0410-bfdd-b5b2a6649095

diff --git a/src/modules/avformat/producer_avformat.c b/src/modules/avformat/producer_avformat.c
index bc7971243fb7e041062502a86327e54f9b463ac4..69d1d3e32b01d3809d9f07f81ac11e8e8b555211 100644 (file)
--- a/src/modules/avformat/producer_avformat.c
+++ b/src/modules/avformat/producer_avformat.c
@@ -272,9 +272,9 @@ static int producer_open( mlt_producer this, char *file )
                        if ( context->duration != AV_NOPTS_VALUE ) 
                        {
                                // This isn't going to be accurate for all formats
-                               mlt_position frames = ( mlt_position )( ( ( double )context->duration / ( double )AV_TIME_BASE ) * fps );
-                               mlt_properties_set_position( properties, "out", frames - 2 );
-                               mlt_properties_set_position( properties, "length", frames - 1 );
+                               mlt_position frames = ( mlt_position )( ( ( double )context->duration / ( double )AV_TIME_BASE ) * fps + 0.5 );
+                               mlt_properties_set_position( properties, "out", frames - 1 );
+                               mlt_properties_set_position( properties, "length", frames - 0 );
                        }
 
                        // Find default audio and video streams
@@ -492,7 +492,7 @@ static int producer_get_image( mlt_frame frame, uint8_t **buffer, mlt_image_form
        double fps = mlt_properties_get_double( properties, "fps" );
 
        // This is the physical frame position in the source
-       int req_position = ( int )( position / fps * source_fps );
+       int req_position = ( int )( position / fps * source_fps + 0.5 );
 
        // Get the seekable status
        int seekable = mlt_properties_get_int( properties, "seekable" );
@@ -552,7 +552,7 @@ static int producer_get_image( mlt_frame frame, uint8_t **buffer, mlt_image_form
                else if ( seekable && ( position < expected || position - expected >= 12 ) )
                {
                        // Calculate the timestamp for the requested frame
-                       int64_t timestamp = ( int64_t )( ( double )req_position / source_fps * AV_TIME_BASE );
+                       int64_t timestamp = ( int64_t )( ( double )req_position / source_fps * AV_TIME_BASE + 0.5 );
                        if ( ( uint64_t )context->start_time != AV_NOPTS_VALUE )
                                timestamp += context->start_time;
                        if ( must_decode )
@@ -606,10 +606,9 @@ static int producer_get_image( mlt_frame frame, uint8_t **buffer, mlt_image_form
                        if ( ret >= 0 && pkt.stream_index == index && pkt.size > 0 )
                        {
                                // Determine time code of the packet
-                               int_position = ( int )( av_q2d( stream->time_base ) * pkt.dts * source_fps );
+                               int_position = ( int )( av_q2d( stream->time_base ) * pkt.dts * source_fps + 0.5 );
                                if ( context->start_time != AV_NOPTS_VALUE )
-                                       int_position -= ( int )( context->start_time * source_fps / AV_TIME_BASE );
-
+                                       int_position -= ( int )( context->start_time * source_fps / AV_TIME_BASE + 0.5 );
                                int last_position = mlt_properties_get_int( properties, "_last_position" );
                                if ( int_position == last_position )
                                        int_position = last_position + 1;